Science.gov

Sample records for gvt monosodium luminol

  1. Neuroprotective effects of the drug GVT (monosodium luminol) are mediated by the stabilization of Nrf2 in astrocytes.

    PubMed

    Reddy, Pichili Vijaya Bhaskar; Lungu, Gina; Kuang, Xianghong; Stoica, George; Wong, Paul K Y

    2010-01-01

    Oxidative stress is implicated in various kinds of neurological disorders, including human immunodeficiency virus (HIV) associated dementia (HAD). Our laboratory has been studying the murine retrovirus ts1, a pathogenic mutant of the Moloney murine leukemia virus (MoMuLV), as a model for HAD. Like HIV in humans, ts1 induces oxidative stress and progressive neurodegeneration in mice. We have shown previously that an antioxidant and anti-inflammatory drug GVT or MSL (monosodium luminol) suppresses ts1-induced oxidative stress, attenuates the development of spongiform encephalopathy, and delays hind limb paralysis in infected mice. It is known that upregulation of the nuclear transcription factor NF-E2-related factor 2 (Nrf2) is involved in upregulating cellular antioxidant defenses. Since Nrf2 is associated with elevation of antioxidant defenses in general, and since GVT suppresses ts1-induced neurodegeneration, our aim in this study was to determine whether GVT neuroprotection is linked to Nrf2 upregulation in the brain. We report here that GVT upregulates the levels of Nrf2, both in primary astrocyte cultures and in brainstem of ts1-infected mice. Significant upregulation of Nrf2 expression by GVT occurs in both the cytosolic and nuclear fractions of cultured astrocytes and brainstem cells. Notably, although GVT treatment increases Nrf2 protein levels in cultured astrocytes and brainstem tissues, Nrf2 mRNA levels are not altered. This suggests that the neuroprotective effects of GVT may be mediated by the stabilization of the Nrf2 protein, allowing continuous upregulation of Nrf2 levels in the astrocytes. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Neuroprotective effects of the drug GVT (monosodium luminol) is mediated by the stabilization of Nrf2 in astrocytes

    PubMed Central

    Reddy, Pichili Vijaya Bhaskar; Lungu, Gina; Kuang, Xianghong; Stoica, George; Wong, Paul KY

    2014-01-01

    Oxidative stress is implicated in various kinds of neurological disorders, including human immunodeficiency virus (HIV) associated dementia (HAD). Our laboratory has been studying the murine retrovirus ts1, a pathogenic mutant of the Moloney murine leukemia virus (MoMuLV), as a model for HAD. Like HIV in humans, ts1 induces oxidative stress and progressive neurodegeneration in mice. We have shown previously that an antioxidant and anti-inflammatory drug GVT or MSL (monosodium luminol) suppresses ts1-induced oxidative stress, attenuates the development of spoorm encephalopathy, and delays hind limb paralysis in infected mice. It is known that upregulation of the nuclear transcription factor NF-E2-related factor 2 (Nrf2) is involved in upregulating cellular antioxidant defenses. Since Nrf2 is associated with elevation of antioxidant defenses in general, and since GVT suppresses ts1-induced neurodegeneration, our aim in this study was to determine whether GVT neuroprotection is linked to Nrf2 upregulation in the brain. We report here that GVT upregulates the levels of Nrf2, both in primary astrocyte cultures and in brainstem of ts1-infected mice. Significant upregulation of Nrf2 expression by GVT occurs in both the cytosolic and nuclear fractions of cultured astrocytes and brainstem cells. Notably, although GVT treatment increases Nrf2 protein levels in cultured astrocytes and brainstem tissues, Nrf2 mRNA levels are not altered. This suggests that the neuroprotective effects of GVT may be mediated by the stabilization of the Nrf2 protein, allowing continuous upregulation of Nrf2 levels in the astrocytes. PMID:20211212

  3. The drug monosodium luminol (GVT) preserves crypt-villus epithelial organization and allows survival of intestinal T cells in mice infected with the ts1 retrovirus.

    PubMed

    Scofield, Virginia L; Yan, Mingshan; Kuang, Xianghong; Kim, Soo-Jin; Wong, Paul K Y

    2009-02-21

    Of the cytopathic retroviruses that affect mammals, including HIV-1, many selectively infect CD4+ T cells and cause immunosuppressive syndromes. These diseases destroy both the thymus and the small and large intestines, after infecting and killing T-lineage cells in both tissues. A mutant of the murine leukemia retrovirus MoMuLV-TB, called ts1, causes this syndrome in susceptible strains of mice. In FVB/N strain mice that are infected at birth, thymic atrophy, CD4+ T cell loss, intestinal collapse, body wasting, and death occur by approximately 30-40 days postinfection (dpi). Apoptosis of ts1-infected T-lineage cells, in the thymus, peripheral lymphoid system and intestines is caused by accumulation of the ts1 mutant viral envelope preprotein gPr80(env), which is inefficiently cleaved into the mature viral proteins gp70 and PrP15E. We show here that ts1 infection in the small intestine is followed by loss of intestinal epithelial cell (IEC) thyroid-stimulating hormone (TSH) and cell cycling gradients (along the crypt-villus axes), accumulation of gPr80(env) in intestinal cells, apoptosis of developing T cells in the lamina propria (LP), and intestinal collapse by approximately 30 dpi. In infected mice treated with the antioxidant drug monosodium luminol (GVT), however, normal intestinal epithelial cell gradients are still in place at 30 dpi, and IECs covering both the crypts and villi contain large amounts of the antioxidant transcription factor Nrf2. In addition, no apoptotic cells are present, and accumulated gpr80(env) is absent from the tissue at this time. We conclude that GVT treatment can make ts1 a noncytopathic virus for intestinal lymphoid cells, as it does for thymocytes [25]. As in the thymus, GVT may protect the intestine by reducing oxidant stress in infected intestinal T cells, perhaps by prevention of gPr80(env) accumulation via Nrf2 upregulation in the IECs. These results identify GVT as a potential therapy for intestinal diseases or inflammatory

  4. Monosodium luminol upregulates the expression of Bcl-2 and VEGF in retrovirus-infected mice through downregulation of corresponding miRNAs.

    PubMed

    Lungu, G; Kuang, X; Stoica, G; Wong, P K Y

    2010-01-01

    The retrovirus ts1 is a mutant of Moloney murine leukemia virus (MoMuLV) that causes neurodegeneration (ND) in susceptible mice. Our previous studies showed that the antioxidant drug monosodium luminol (GVT) prevented the development of ND in ts1-infected mice. In this study, we analyzed effect of GVT on the expression of B-cell lymphoma-2 protein (Bcl-2) and vascular endothelial growth factor (VEGF) in central nervous system (CNS) tissues of these animals. Our data showed that GVT treatment of ts1-infected mice significantly increased their expression of Bcl-2 and VEGF in brainstem compared with ts1-infected untreated mice. We also studied the expression of specific microRNAs (miRNAs) such as miRNA-15 and -16 (targeting Bcl-2), and miRNA-20 (targeting VEGF). We found that the expression of miRNAs inversely correlated with the upregulation of their target proteins in ts1-infected untreated as well as in GVT-treated-ts1-infected mice. The data showed that GVT treatment prevented ts1-induced ND at least in part by upregulating Bcl-2 and VEGF expression, what likely occurred as a consequence of downregulation of their corresponding miRNAs.

  5. Retrovirus-induced oxidative stress with neuroimmunodegeneration is suppressed by antioxidant treatment with a refined monosodium alpha-luminol (Galavit).

    PubMed

    Jiang, Yuhong; Scofield, Virginia L; Yan, Mingshan; Qiang, Wenan; Liu, Na; Reid, Amy J; Lynn, William S; Wong, Paul K Y

    2006-05-01

    Oxidative stress is involved in many human neuroimmunodegenerative diseases, including human immunodeficiency virus disease/AIDS. The retrovirus ts1, a mutant of Moloney murine leukemia virus, causes oxidative stress and progressive neuro- and immunopathology in mice infected soon after birth. These pathological changes include spongiform neurodegeneration, astrogliosis, thymic atrophy, and T-cell depletion. Astrocytes and thymocytes are directly infected and killed by ts1. Neurons are not infected, but they also die, most likely as an indirect result of local glial infection. Cytopathic effects of ts1 infection in cultured astrocytes are associated with accumulation of the viral envelope precursor protein gPr80env in the endoplasmic reticulum (ER), which triggers ER stress and oxidative stress. We have reported (i) that activation of the Nrf2 transcription factor and upregulation of antioxidative defenses occurs in astrocytes infected with ts1 in vitro and (ii) that some ts1-infected astrocytes survive infection by mobilization of these pathways. Here, we show that treatment with a refined monosodium alpha-luminol (Galavit; GVT) suppresses oxidative stress and Nrf2 activation in cultured ts1-infected astrocytes. GVT treatment also inhibits the development of spongiform encephalopathy and gliosis in the central nervous system (CNS) in ts1-infected mice, preserves normal cytoarchitecture in the thymus, and delays paralysis, thymic atrophy, wasting, and death. GVT treatment of infected mice reduces ts1-induced oxidative stress, cell death, and pathogenesis in both the CNS and thymus of treated animals. These studies suggest that oxidative stress mediates ts1-induced neurodegeneration and T-cell loss.

  6. Retrovirus-Induced Oxidative Stress with Neuroimmunodegeneration Is Suppressed by Antioxidant Treatment with a Refined Monosodium α-Luminol (Galavit)

    PubMed Central

    Jiang, Yuhong; Scofield, Virginia L.; Yan, Mingshan; Qiang, Wenan; Liu, Na; Reid, Amy J.; Lynn, William S.; Wong, Paul K. Y.

    2006-01-01

    Oxidative stress is involved in many human neuroimmunodegenerative diseases, including human immunodeficiency virus disease/AIDS. The retrovirus ts1, a mutant of Moloney murine leukemia virus, causes oxidative stress and progressive neuro- and immunopathology in mice infected soon after birth. These pathological changes include spongiform neurodegeneration, astrogliosis, thymic atrophy, and T-cell depletion. Astrocytes and thymocytes are directly infected and killed by ts1. Neurons are not infected, but they also die, most likely as an indirect result of local glial infection. Cytopathic effects of ts1 infection in cultured astrocytes are associated with accumulation of the viral envelope precursor protein gPr80env in the endoplasmic reticulum (ER), which triggers ER stress and oxidative stress. We have reported (i) that activation of the Nrf2 transcription factor and upregulation of antioxidative defenses occurs in astrocytes infected with ts1 in vitro and (ii) that some ts1-infected astrocytes survive infection by mobilization of these pathways. Here, we show that treatment with a refined monosodium α-luminol (Galavit; GVT) suppresses oxidative stress and Nrf2 activation in cultured ts1-infected astrocytes. GVT treatment also inhibits the development of spongiform encephalopathy and gliosis in the central nervous system (CNS) in ts1-infected mice, preserves normal cytoarchitecture in the thymus, and delays paralysis, thymic atrophy, wasting, and death. GVT treatment of infected mice reduces ts1-induced oxidative stress, cell death, and pathogenesis in both the CNS and thymus of treated animals. These studies suggest that oxidative stress mediates ts1-induced neurodegeneration and T-cell loss. PMID:16611916

  7. alpha-Luminol prevents decreases in glutamate, glutathione, and glutamine synthetase in the retinas of glaucomatous DBA/2J mice.

    PubMed

    Gionfriddo, Juliet R; Freeman, Kate S; Groth, Allyson; Scofield, Virginia L; Alyahya, Khaleel; Madl, James E

    2009-01-01

    To test the hypothesis that in DBA/2J mice, oxidative stress decreases glutamine synthetase (GS) levels resulting in a loss of neuronal glutamate and that the antioxidant alpha-luminol (GVT) decreases this stress and glutamate loss in some types of glaucoma. DBA/2J mice were separated into two groups, of which one was not treated, and the other treated with GVT in the drinking water. At 7 months of age, retinas were examined from five untreated DBA/2J mice, seven GVT-treated mice, and five C57BL/6 mice (negative controls). Serial 0.5 microm plastic sections were immunogold stained for glutamate, GS, and total glutathione, followed by image analysis for staining patterns and density. Focal decreases in glutamate immunostaining were common in the inner nuclear layer (INL) of DBA/2J retinas, but not in C57BL/6 or GVT-treated DBA/2J retinas. Decreases in glutathione and GS immunostaining were found in DBA/2J retinal regions where neuronal glutamate immunostaining was reduced. Retinas from GVT-treated DBA/2J had no significant decreases in INL levels of glutamate, glutathione, or GS. Retinas of dogs with primary glaucoma are reported to have focal depletion of neuronal glutamate. In DBA/2J mice, similar changes occur prior to the development of clinical disease. In these focal glutamate-depleted regions, levels of glutathione and GS are also reduced, consistent with the hypothesis that oxidative stress contributes to retinal changes in glaucoma. The ability of GVT, an antioxidant, to inhibit retinal abnormalities in DBA/2J mice provides further support for this hypothesis.

  8. Monosodium Luminol for Improving Brain Function in Gulf War Illness

    DTIC Science & Technology

    2015-10-01

    chronic multi-symptom health problem, which afflicts nearly 30% of veterans who served in the Persian Gulf War-1 (PGW-1). Brain dysfunction, typified...by memory dysfunction, depression and anxiety, is one of the major health issues in GWI. While the precise etiology of GWI is unknown, several...the use of pesticides for the area protection and insect repellants on the skin and uniforms. The pesticides included the insecticide permethrin

  9. Peroxynitrite-induced luminol chemiluminescence.

    PubMed Central

    Radi, R; Cosgrove, T P; Beckman, J S; Freeman, B A

    1993-01-01

    Vascular endothelial cells, smooth muscle cells, macrophages, neutrophils, Kupffer cells and other diverse cell types generate superoxide (O2.-) and nitric oxide (.NO), which can react to form the potent oxidant peroxynitrite anion (ONOO-). Peroxynitrite reacted with luminol to yield chemiluminescence which was greatly enhanced by bicarbonate. The quantum chemiluminescence yield of the ONOO- reaction with luminol in bicarbonate was approx. 10(-3). Chemiluminescence was superoxide dismutase-inhibitable, indicating that O2.- was a key intermediate for chemiexcitation. O2.- appears to be formed secondarily to the reaction of a bicarbonate-peroxynitrite complex with luminol, yielding luminol radical and O2.-. Luminol radical reacts with O2.- to form the unstable luminol endoperoxide, which follows the light-emitting pathway. Neither .NO nor O2.- alone were capable of directly inducing significant luminol chemiluminescence in our assay systems. These results suggest that ONOO- can be a critical unrecognized mediator of cell-derived luminol chemiluminescence reported in previous studies. In addition, it is shown that bicarbonate can participate in secondary oxidation reactions after reacting with ONOO-. PMID:8382481

  10. Shared biology of GVHD and GVT effects: potential methods of separation.

    PubMed

    Fowler, Daniel H

    2006-03-01

    The difficult separation of clinical graft-versus-tumor (GVT) effects from graft-versus-host disease (GVHD) reflects their shared biology. Experimental approaches to mediate GVT effects while limiting GVHD include: (1) allograft T cell depletion followed by immune enhancement; (2) modulation of T cell dose or T cell subset composition; (3) donor lymphocyte infusion; (4) reduced-intensity host preparation; (5) modulation of Th1/Th2 and Tc1/Tc2 cell balance; (6) cytokine therapy or neutralization; (7) T regulatory cell therapy; (8) co-stimulatory pathway modulation; (9) chemokine pathway modulation; (10) induction of antigen-specific T cells; (11) alloreactive NK cell therapy; and (12) targeted pharmaceutical inhibition of proteosome, mammalian target of rapamycin, and histone deacetylase pathways. Clearly, a multitude of approaches exist that hold promise for separating GVT effects from GVHD. Future success in this endeavor will require a strong commitment towards translational research and continued advances in cell, vaccine, cytokine, monoclonal antibody, and targeted molecular therapy.

  11. Discrete Event Execution with One-Sided and Two-Sided GVT Algorithms on 216,000 Processor Cores

    SciTech Connect

    Perumalla, Kalyan S; Park, Alfred J; Tipparaju, Vinod

    2014-01-01

    Global virtual time (GVT) computation is a key determinant of the efficiency and runtime dynamics of parallel discrete event simulations (PDES), especially on large-scale parallel platforms. Here, three execution modes of a generalized GVT computation algorithm are studied on high-performance parallel computing systems: (1) a synchronous GVT algorithm that affords ease of implementation, (2) an asynchronous GVT algorithm that is more complex to implement but can relieve blocking latencies, and (3) a variant of the asynchronous GVT algorithm to exploit one-sided communication in extant supercomputing platforms. Performance results are presented of implementations of these algorithms on up to 216,000 cores of a Cray XT5 system, exercised on a range of parameters: optimistic and conservative synchronization, fine- to medium-grained event computation, synthetic and non-synthetic applications, and different lookahead values. Performance of up to 54 billion events executed per second is registered. Detailed PDES-specific runtime metrics are presented to further the understanding of tightly-coupled discrete event dynamics on massively parallel platforms.

  12. Genotoxicity of monosodium glutamate.

    PubMed

    Ataseven, Nazmiye; Yüzbaşıoğlu, Deniz; Keskin, Ayten Çelebi; Ünal, Fatma

    2016-05-01

    Monosodium glutamate (MSG) is one of the most widely used flavor enhancers throughout the world. The aim of this study is to investigate the genotoxic potential of MSG by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), cytokinesis-blocked micronucleus (CBMN), and random amplified polymorphic DNA-polimerase chain reaction (RAPD-PCR) in cultured human lymphocytes and alkaline comet assays in isolated human lymphocytes, which were incubated with six concentrations (250, 500, 1000, 2000, 4000 and 8000 μg/mL) of MSG. The result of this study indicated that MSG significantly and dose dependently increased the frequencies of CAs, SCE and MN in all treatments and times, compared with control. However, the replication (RI) and nuclear division indices (NDI) were not affected. In this paper, in vitro genotoxic effects of the MSG was also investigated on human peripheral lymphocytes by analysing the RAPD-PCR with arbitrary 10-mer primers. The changes occurring in RAPD profiles after MSG treatment include increase or decrease in band intensity and gain or loss of bands. In the comet assay, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1-h in vitro exposure. Our results demonstrate that MSG is genotoxic to the human peripheral blood lymphocytes in vitro.

  13. Kinetics of luminol sonochemiluminescence quenched by purines.

    PubMed

    Wang, Jian; Lai, Yongquan; Chen, Meili; Jiang, Zhou; Chen, Guonan

    2013-01-01

    A homogeneous chemiluminescence (CL) reaction was initiated by ultrasound irradiation. Luminol sonochemiluminescence (SCL) reaction kinetics were determined under pseudo-first-order conditions, and the reaction followed the model for simple rise-fall kinetics. In addition, SCL quenching reactions induced by purines were also investigated in which the interactions between luminol and purines were analysed using the Stern-Volmer (S-V) mechanism. The results implied that the high rate constant of luminol CL quenched by purines may be attributed to ground state interactions originating from hydrogen bonding. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Illuminating the health and safety of luminol.

    PubMed

    Larkin, Tony; Gannicliffe, Chris

    2008-06-01

    Luminol is a reagent that is used to enhance areas of non-visible bloodstaining and it is one of the most sensitive of such reagents available to the forensic scientist. However, its use, particularly within the UK and some other European countries, has been limited, predominantly due to concerns about the health and safety of the reagent. This paper reviews the literature currently available regarding the health and safety of luminol, and in the authors' view demonstrates that there are no significant health and safety concerns with the preparation of luminol solution and its application at the crime scene or in the laboratory, providing suitable precautions are taken.

  15. Luminol chemiluminescence under interaction with heteropoly acids.

    PubMed

    Zui, Oleg; Takahashi, Hiroki; Hori, Toshitaka; Hinoue, Teruo

    2009-05-15

    Interaction of luminol with phosphomolybdic, phosphovanadomolybdic and silicomolybdic acids was studied by examination of chemiluminescence spectra, measurement of ESR spectra, investigation of reaction order, and elucidation of inhibition effects. A scheme of the reaction mechanism is proposed.

  16. The Crystallization of Monosodium Urate

    PubMed Central

    Martillo, Miguel A.; Nazzal, Lama; Crittenden, Daria B.

    2014-01-01

    Gout is a common crystal-induced arthritis, in which monosodium urate (MSU) crystals precipitate within joints and soft tissues and elicit an inflammatory response. The causes of elevated serum urate and the inflammatory pathways activated by MSU crystals have been well studied, but less is known about the processes leading to crystal formation and growth. Uric acid, the final product of purine metabolism, is a weak acid that circulates as the deprotonated urate anion under physiologic conditions, and combines with sodium ions to form MSU. MSU crystals are known to have a triclinic structure, in which stacked sheets of purine rings form the needle-shaped crystals that are observed microscopically. Exposed, charged crystal surfaces are thought to allow for interaction with phospholipid membranes and serum factors, playing a role in the crystal-mediated inflammatory response. While hyperuricemia is a clear risk factor for gout, local factors have been hypothesized to play a role in crystal formation, such as temperature, pH, mechanical stress, cartilage components, and other synovial and serum factors. Interestingly, several studies suggest that MSU crystals may drive the generation of crystal-specific antibodies that facilitate future MSU crystallization. Here, we review MSU crystal biology, including a discussion of crystal structure, effector function, and factors thought to play a role in crystal formation. We also briefly compare MSU biology to that of uric acid stones causing nephrolithasis, and consider the potential treatment implications of MSU crystal biology. PMID:24357445

  17. On the fluorescence of luminol in a silver nanoparticles complex.

    PubMed

    Voicescu, Mariana; Ionescu, Sorana

    2013-05-01

    The photophysical properties of luminol in a silver nanoparticles complex have been studied by steady-state and time resolved fluorescence spectroscopy. The effect of the serum albumin on the luminol fluorescence in the silver nanoparticles has been also investigated. It was found that the fluorescence quantum yield value of luminol in a silver nanoparticles complex is φ = 0.00407. The decrease of the average fluorescence lifetime value of the luminol in the silver nanoparticles complex was found to be low, <τ> = 1.712 ns. The luminol does not bind to the serum albumins in the presence of silver nanoparticles. The formation of a new species of luminol on silver nanoparticles is discussed. The results have influence regarding the use of luminol as an assay for bio-analytical applications.

  18. The influence of dioxygen on luminol chemiluminescence.

    PubMed

    Baj, Stefan; Krawczyk, Tomasz; Staszewska, Karina

    2009-01-01

    Assays of peroxy compounds are commonly performed after chromatographic separation of analysed mixtures. In high-performance liquid chromatography (HPLC), solvent reservoirs are sparged by helium or inline vacuum-degassed in order to control the compressibility of the solvents for efficient pumping. In this study, we investigated the influence of degassing the reaction solution on the light output of the hemin-catalyzed luminol oxidation by various oxidants. We found that, when t-butyl hydroperoxide, hydrogen peroxide, n-butyl hydroperoxide, iodosobenzene and iodobenzene diacetate were used as oxidants, the luminol chemiluminescence was lowered by 50-70% compared with an equilibrated and degassed solution. The opposite effect was observed when dibenzoyl peroxide and 3-chloroperoxybenzoic acid were used as oxidants, as the chemiluminescence increased by approximately 20-30%. The reduced chemiluminescence was explained based on the known role of dioxygen in luminol chemiluminescence. The enhancement of chemiluminescence was rationalized by suggesting an alternative mechanism of luminol oxidation valid for peroxyacids and diacyl peroxides in which the reaction of a peroxyacid anion with the diazaquinone led to light emission with a higher quantum yield than the usual path, which is suppressed by the removal of dioxygen from the reaction solution.

  19. Luminol chemiluminescence catalysed by colloidal platinum nanoparticles.

    PubMed

    Xu, Sheng-Liang; Cui, Hua

    2007-01-01

    Platinum colloids prepared by the reduction of hexachloroplatinic acid with citrate in the presence of different stabilizers were found to enhance the chemiluminescence (CL) of the luminol-H(2)O(2) system, and the most intensive CL signals were obtained with citrate-protected Pt colloids synthesized with citrate as both a reductant and a stabilizer. Light emission was intense and reproducible. Transmission electron microscopy and X-ray photoelectron spectroscopy studies were conducted before and after the CL reaction to investigate the possible CL enhancement mechanism. It is suggested that this CL enhancement is attributed to the catalysis of platinum nanoparticles, which could accelerate the electron-transfer process and facilitate the CL radical generation in aqueous solution. The effects of Pt colloids prepared by the hydroborate reduction were also investigated. The application of the luminol-H(2)O(2)-Pt colloids system was exploited for the determination of compounds such as uric acid, ascorbic acid, phenols and amino acids.

  20. Luminol-based nitrogen dioxide detector

    SciTech Connect

    Wendel, G.J.; Stedman, D.H.; Cantrell, C.A.; Damrauer, L.

    1983-05-01

    An instrument for the continuous detection of NO/sub 2/ in the sub-part-per-billion range is described. The instrument is based upon the chemiluminescent reaction between NO/sub 2/ in air and luminol (5-amino-2,3-dihydro-1,4-phthalazinedione) in alkaline solution. The present detector exhibits a 2-Hz response speed to changes of +/-20 ppB and a field detection limit of 30 parts per trillion. The instrumental technique has been expanded to measure NO by the catalytic oxidation of NO to NO/sub 2/ using CrO/sub 3/ on silica gel as the oxidizing agent; however, at low ambient NO concentrations some drift in the NO zero is observed. Interference from ambient O/sub 3/ is elimated by modification of the inlet system and luminol solution.

  1. Inhibition of bleach-induced luminol chemiluminescence.

    PubMed

    Kent, Erina J M; Elliot, Douglas A; Miskelly, Gordon M

    2003-01-01

    The luminol chemiluminescence presumptive test for blood is based on the mild peroxidase activity of hemoglobin in basic peroxide solution. However, this test is subject to interference by strong oxidants, certain transition metal ions, and true peroxidases. This paper reports methods for reducing the interference caused by hypochlorite-containing bleaches. Amines such as 1,2-diaminoethane react rapidly with hypochlorite without interfering significantly with the hemoglobin-catalyzed oxidation. Thus, addition of 0.1 mol/L 1,2-diaminoethane to a standard luminol-peroxide spray lead to almost complete inhibition of hypochlorite-induced chemiluminescence while satisfactory chemiluminescence was still observed from bloodstains. If time allows, an alternative method for reducing interference from hypochlorite bleach is to wait several days until the bloodstains have dried thoroughly, by which time the hypochlorite will have decomposed.

  2. Improving Luminol Blood Detection in Forensics.

    PubMed

    Stoica, Bogdan A; Bunescu, Sabina; Neamtu, Andrei; Bulgaru-Iliescu, Diana; Foia, Liliana; Botnariu, Eosefina Gina

    2016-09-01

    The aim of this study was to develop chemical improvements to the original Weber protocol, in order to increase the intensity and time length of light emission and to eliminate false-positive reactions. The intensity and duration of light were measured on serial blood dilutions using a plate reader chemiluminometer. Blood stains of various concentrations were impregnated in pure cellulose, dried, and luminol solution was added with/without the potential enhancers. An in silico study was also conducted, aiming to demonstrate the enhancing mechanism of hemoglobin denaturation using 8 M urea. The luminol blood detection test revealed important improvements after urea pretreatment or in the presence of monochloro-triazinyl-β-cyclodextrin. This approach also eliminated the false-positive reaction from sodium hypochlorite. These improvements could provide a higher sensitivity under particular circumstances such as old or washed blood stains, leading to a better localization for further DNA typing and higher quality photographic analysis.

  3. Does luminol chemiluminescence detect free radical scavengers?

    PubMed Central

    Clapperton, M; McMurray, J; Fisher, A C; Dargie, H J

    1995-01-01

    Thiol compounds have been reported to abolish hypoxanthine/xanthine oxidase induced luminol chemiluminescence and this effect has been attributed to scavenging of superoxide (O2-)/(H2O2) produced from hypoxanthine/xanthine oxidase. Yet other workers have reported that thiol compounds have shown little, if any, reactivity towards O2-/H2O2. The aim of this study was to examine the discrepancy between these two sets of findings further. Captopril (a thiol angiotensin-converting enzyme (ACE) inhibitor) and MPG (a simple thiol) were observed to abolish hypoxanthine/xanthine oxidase induced chemiluminescence. The reactivity of captopril and MPG towards O2-/H2O2 was then determined by measurement of thiol oxidation in captopril and MPG after their incubation with hypoxanthine/xanthine oxidase. Incubation (at 10 min, 37 degrees C) with 4 mM hypoxanthine/0.03 u ml-1 xanthine oxidase resulted in 7% and 20% thiol oxidation in captopril and MPG (at 1 mM) respectively. Captopril and MPG, therefore, appeared to be ineffective scavengers of oxidants produced by hypoxanthine/xanthine oxidase. Captopril and MPG also did not affect urate production or oxygen consumption by xanthine oxidase which indicated that captopril and MPG quench luminol chemiluminescence by a mechanism that excludes the inhibition of xanthine oxidase. Hypoxanthine/xanthine oxidase induced luminol chemiluminescence may, therefore, be an unsuitable method for measuring free radical scavenging activity by drugs. PMID:7654490

  4. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000524120

    SciTech Connect

    Taylor-Pashow, K.

    2012-08-29

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot No.46000524120 qualification and the 14 verification samples met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.

  5. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000619120

    SciTech Connect

    Taylor-Pashow, K.

    2012-09-06

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot #46000619120 qualification and the 13 verification samples met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.

  6. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #071311

    SciTech Connect

    Taylor-Pashow, K.

    2011-10-04

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot No.071311 qualification and 12 verification samples met all the requirements in the specification indicating the material is acceptable for use in the process.

  7. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #052511

    SciTech Connect

    Taylor-Pashow, K.

    2011-08-22

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot No.052511 qualification and 14 verification samples met all the requirements in the specification indicating the material is acceptable for use in the process.

  8. Analysis of Harrell Monosodium Titanate Lot #46000824120

    SciTech Connect

    Taylor-Pashow, K. M.L.

    2013-01-23

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot #46000824120 qualification and the 16 verification samples failed to meet the specification for weight percent solids. All of the pails sampled and tested contained less than 15 wt % MST solids.

  9. Analysis of Harrell Monosodium Titanate Lot #46000908120

    SciTech Connect

    Taylor-Pashow, K. M.L.

    2013-01-23

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot #46000908120 qualification and the 16 verification samples failed to meet the specification for weight percent solids. All of the pails sampled and tested contained less than 15 wt % MST solids.

  10. Luminol activity of horseradish peroxidase mutants mimicking a proposed binding site for luminol in Arthromyces ramosus peroxidase.

    PubMed

    Tanaka, M; Ishimori, K; Morishima, I

    1999-08-10

    To enhance the oxidation activity for luminol in horseradish peroxidase (HRP), we have prepared three HRP mutants by mimicking a possible binding site for luminol in Arthromyces ramosus peroxidase (ARP) which shows 500-fold higher oxidation activity for luminol than native HRP. Spectroscopic studies by (1)H NMR revealed that the chemical shifts of 7-propionate and 8-methyl protons of the heme in cyanide-ligated ARP were deviated upon addition of luminol (4 mM), suggesting that the charged residues, Lys49 and Glu190, which are located near the 7-propionate and 8-methyl groups of the heme, are involved in the specific binding to luminol. The positively charged Lys and negatively charged Glu were introduced into the corresponding positions of Ser35 (S35K) and Gln176 (Q176E) in HRP, respectively, to build the putative binding site for luminol. A double mutant, S35K/Q176E, in which both Ser35 and Gln176 were replaced, was also prepared. Addition of luminol to the HRP mutants induced more pronounced effects on the resonances from the heme substituents and heme environmental residues in the (1)H NMR spectra than that to the wild-type enzyme, indicating that the mutations in this study induced interactions with luminol in the vicinity of the heme. The catalytic efficiencies (V(max)/K(m)) for luminol oxidation of the S35K and S35K/Q176E mutants were 1.5- and 2-fold improved, whereas that of the Q176E mutant was slightly depressed. The increase in luminol activity of the S35K and S35K/Q176E mutants was rather small but significant, suggesting that the electrostatic interactions between the positive charge of Lys35 and the negative charge of luminol can contribute to the effective binding for the luminol oxidation. On the other hand, the negatively charged residue would not be so crucial for the luminol oxidation. The absence of drastic improvement in the luminol activity suggests that introduction of the charged residues into the heme vicinity is not enough to enhance the

  11. Luminol as a fluorescent acid-base indicator.

    PubMed

    Erdey, L; Buzás, I; Vigh, K

    1966-03-01

    The acid and base dissociation constants of luminol are determined at various ionic strengths. The transition interval occurs at pH 7.7-9.0, therefore luminol is a fluorescent indicator for the titration of strong and weak acids and strong bases. Its value as an indicator is established by titrating milk, red wine and cherry juice.

  12. Effects of luminol on the subsequent analysis of bloodstains.

    PubMed

    Laux, D L

    1991-09-01

    The effects of luminol upon additional presumptive chemical tests, subsequent confirmatory blood tests, species determination by immunoelectrophoresis, ABO typing by absorption elution, and genetic marker analysis by multienzyme system electrophoresis were examined. Results indicate that luminol does not affect additional presumptive chemical tests, confirmatory tests, species determination, or ABO typing, but does affect certain genetic marker systems.

  13. Study on the proteins-luminol binding by use of luminol as a fluorescence probe

    NASA Astrophysics Data System (ADS)

    He, Xili; Song, Zhenghua

    2013-10-01

    In this paper, a new mathematical equation of lg(F0 - F)/F = 1/nlg[P] + 1/nlgKa, which was used to obtain interaction parameters (the binding constant Ka and the number of binding sites n) between the protein and the small molecule ligand by using the ligand as a fluorescence (FL) probe, was constructed for the first time. The interaction parameters between myoglobin, catalase, lysozyme, bovine serum albumin (BSA) and luminol were obtained by this equation with luminol used as a FL probe, showing that the binding constants Ka were 8.78 × 105, 4.47 × 105, 4.21 × 104 and 3.95 × 104 respectively, and the number of binding sites n approximately equaled to 1.0 for myoglobin, catalase, and 2.0 for lysozyme, BSA. The interactions of ferritin, ovalbumin, aldolase, chymotrypsinogen and ribonuclease with luminol were also studied by this method. The binding constants Ka were at 104-105 level, and the number of binding sites n mostly approximately equaled to 2.0. The binding ability of luminol to the studied proteins followed the pattern: myoglobin > aldolase > ferritin > ovalbumin > catalase > ribonuclease > lysozyme > BSA > chymotrypsinoge.

  14. Study on the proteins-luminol binding by use of luminol as a fluorescence probe.

    PubMed

    He, Xili; Song, Zhenghua

    2013-10-01

    In this paper, a new mathematical equation of lg(F0-F)/F=1/nlg[P]+1/nlgKa, which was used to obtain interaction parameters (the binding constant Ka and the number of binding sites n) between the protein and the small molecule ligand by using the ligand as a fluorescence (FL) probe, was constructed for the first time. The interaction parameters between myoglobin, catalase, lysozyme, bovine serum albumin (BSA) and luminol were obtained by this equation with luminol used as a FL probe, showing that the binding constants Ka were 8.78×10(5), 4.47×10(5), 4.21×10(4) and 3.95×10(4) respectively, and the number of binding sites n approximately equaled to 1.0 for myoglobin, catalase, and 2.0 for lysozyme, BSA. The interactions of ferritin, ovalbumin, aldolase, chymotrypsinogen and ribonuclease with luminol were also studied by this method. The binding constants Ka were at 10(4)-10(5) level, and the number of binding sites n mostly approximately equaled to 2.0. The binding ability of luminol to the studied proteins followed the pattern: myoglobin>aldolase>ferritin>ovalbumin>catalase>ribonuclease>lysozyme>BSA>chymotrypsinoge. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Two techniques for eliminating luminol interference material and flow system configurations for luminol and firefly luciferase systems

    NASA Technical Reports Server (NTRS)

    Thomas, R. R.

    1976-01-01

    Two methods for eliminating luminol interference materials are described. One method eliminates interference from organic material by pre-reacting a sample with dilute hydrogen peroxide. The reaction rate resolution method for eliminating inorganic forms of interference is also described. The combination of the two methods makes the luminol system more specific for bacteria. Flow system designs for both the firefly luciferase and luminol bacteria detection systems are described. The firefly luciferase flow system incorporating nitric acid extraction and optimal dilutions has a functional sensitivity of 3 x 100,000 E. coli/ml. The luminol flow system incorporates the hydrogen peroxide pretreatment and the reaction rate resolution techniques for eliminating interference. The functional sensitivity of the luminol flow system is 1 x 10,000 E. coli/ml.

  16. 78 FR 76321 - Monosodium Glutamate From China and Indonesia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... COMMISSION Monosodium Glutamate From China and Indonesia Determinations On the basis of the record \\1... injured by reason of imports from China and Indonesia of monosodium glutamate, provided for in subheading... United States at less than fair value (LTFV) and subsidized by the Governments of China and Indonesia....

  17. Synthesis and Characterization of Luminol Persulphate Chemiluminescence in Aqueous Amines

    NASA Astrophysics Data System (ADS)

    Raut, V. M.; More, P. S.; Khollam, Y. B.; Sonone, R. S.; Kondawar, S. B.; Koinkar, Pankaj

    The chemiluminescence (CL) emission spectra of luminol were recorded using Fuss spectrograph in different aqueous aliphatic amines using sodium persulphate alone and mixture with hydrogen peroxide as an oxidant. The CL emission spectra after resolution showed two emission bands at 425 and 455 nm. The CL mechanism was explained on the basis of two exited state species formed during oxidation of luminol. The CL of luminol is found to be very weak as persulphate slowly produced oxygen. The glow become intense with time as more and more oxygen is made available for oxidation of luminol. The mixture of hydrogen peroxide and sodium persulphate is found to be more effective in producing intense and long lived CL glow for luminol. The CL emission band of luminol by using sodium persulphate and mixture with hydrogen peroxide is explained on the basis of formation of exited singlet and triplet state of 3-aminophthalate ion (3-APA). The shorter wavelength emission band of 425 nm is found to be very weak in intensity as compared to longer wavelength emission band of 455 nm. Thus phosphoresce is favored in case of persulphate CL of luminol.

  18. Method and apparatus for eliminating luminol interference material

    NASA Technical Reports Server (NTRS)

    Jeffers, E. L.; Thomas, R. R. (Inventor)

    1979-01-01

    A method and apparatus for removing porphyrins from a fluid sample which are unrelated to the number of bacteria present in the sample and prior to combining the sample with luminol reagent to produce a light reaction is disclosed. The method involves a pre-incubation of the sample with a dilute concentration of hydrogen peroxide which inactivates the interfering soluble porphyrins. Further, by delaying taking a light measurement for a predetermined time period after combining the hydrogen peroxide-treated water sample with a luminol reagent, the luminescence produced by the reaction of the luminol reagent with ions present in the solution, being short lived, will have died out so that only porphyrins within the bacteria which have been released by rupturing the cells with the sodium hydroxide in the luminol reagent, will be measured. The measurement thus obtained can then be related to the concentration of live and dead bacteria in the fluid sample.

  19. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT 46000908120

    SciTech Connect

    Taylor-Pashow, K.

    2014-04-09

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The original Harrell Industries Lot #46000908120 qualification and 16 verification samples received in October 2012 failed to meet the specification for weight percent solids. All of the pails sampled and tested contained less than 15 wt % MST solids. The lot was returned to the vendor, and in February 2014 a new qualification sample and set of 16 verification samples were received from this lot. The new lot met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.

  20. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT 46000824120

    SciTech Connect

    Taylor-Pashow, K.

    2014-04-09

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The original Harrell Industries Lot #46000824120 qualification and 16 verification samples received in September 2012 failed to meet the specification for weight percent solids. All of the pails sampled and tested contained less than 15 wt % MST solids. The lot was returned to the vendor, and in February 2014 a new qualification sample and set of 14 verification samples were received from this lot. The new lot met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.

  1. Aspirin can stimulate luminol-enhanced chemiluminescence of activated platelets.

    PubMed

    Gabbasov, Zufar; Ivanova, Oksana; Kogan-Yasny, Victor; Vasilieva, Elena

    2010-01-01

    A preliminary investigation was conducted into the influence of aspirin on the luminol-enhanced chemiluminescence of platelets stimulated with platelet-activating factor (PAF). Ten coronary artery disease patients and six volunteers without coronary artery disease were included in the study. All the patients received aspirin (daily dose, 100 mg) for at least 10 days before in vitro experiments. Luminol-enhanced luminescence of platelet-rich plasma samples mixed with a PAF solution was measured. After stimulation of platelets with PAF, we did not find a luminol-enhanced chemiluminescent response either in the non-coronary artery disease volunteers or in eight out of the 10 coronary artery disease patients examined. However, in samples from two patients where platelets were stimulated with PAF reactive oxygen species were formed. This ability was expressed as an intensive luminol-enhanced luminescence of activated platelets. Such a reaction was observed against the background of the administration of aspirin. The addition of aspirin to a test tube considerably enhanced the intensity of chemiluminescence. In one case, the cancellation of aspirin was accompanied by diminution of the intensity of luminol-enhanced chemiluminescence of platelets. The clinical significance of this phenomenon is unknown.

  2. Luminol-hydrogen peroxide chemiluminescence produced by sweet potato peroxidase.

    PubMed

    Alpeeva, Inna S; Yu Sakharov, Ivan

    2007-01-01

    Anionic sweet potato peroxidase (SPP; Ipomoea batatas) was shown to efficiently catalyse luminol oxidation by hydrogen peroxide, forming a long-term chemiluminescence (CL) signal. Like other anionic plant peroxidases, SPP is able to catalyse this enzymatic reaction efficiently in the absence of any enhancer. Maximum intensity produced in SPP-catalysed oxidation of luminol was detected at pH 7.8-7.9 to be lower than that characteristic of other peroxidases (8.4-8.6). Varying the concentrations of luminol, hydrogen peroxide and Tris buffer in the reaction medium, we determined favourable conditions for SPP catalysis (100 mmol/L Tris-HCl buffer, pH 7.8, containing 5 mmol/L hydrogen peroxide and 8 mmol/L luminol). The SPP detection limit in luminol oxidation was 1.0 x 10(-14) mol/L. High sensitivity in combination with the long-term CL signal and high stability is indicative of good promise for the application of SPP in CL enzyme immunoassay.

  3. On the structure of luminol sodium salts

    NASA Astrophysics Data System (ADS)

    Rybakov, V. B.; Chernyshev, V. V.; Paseshnichenko, K. A.; Sheludyakov, V. D.; Belyakov, N. G.; Boziev, R. S.; Mochalov, V. N.; Storozhenko, P. A.

    2014-05-01

    The structures of Tamerit® ( A) and Galavit® ( B) pharmaceutical preparations have been solved by X-Ray single crystal and powder diffraction. These are luminol sodium salts possessing immunomodulatory and anti-inflammatory properties. It is shown that Tamerit® ( A) is a hydrated salt, while Galavit® ( B) is a mixture of two polymorphic modifications ( B1 and B2) of anhydrous salt. Compound A is crystallized in a monoclinic system: a = 8.3429(4) Å, b = 22.0562(11) Å, c = 5.2825(2) Å, β = 99.893(3)°, V = 957.59(8) Å3, and Z = 4; sp. gr. P21/ c. Compound B1 is crystallized in a monoclinic system: a = 14.7157(18), b = 3.7029(19), c = 16.0233(15) Å, β = 116.682(13)°, V = 780.1(4) Å3, and Z = 4; sp. gr. P21/ c. Compound B2 is crystallized in an orthorhombic system: a = 27.7765(15) Å, b = 3.3980(19) Å, c = 8.1692(19) Å, V = 771.0(5) Å3, and Z = 4; sp. gr. Pna21. The absence of phase transitions between the B1 and B2 polymorphs has been established by differential scanning calorimetry.

  4. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #081811

    SciTech Connect

    Taylor-Pashow, K.; Fink, S.

    2011-10-28

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot No.081811 qualification and 12 verification samples met all the requirements in the specification, with the possible exception of the geometric standard deviation for particle size. Two subsamples from the qualification sample were analyzed, giving results of 3.82 and 3.28, respectively, for the geometric standard deviation. The specification is {le}3.5. The results for both samples met the remaining particle size specifications, i.e. <10 vol% below 0.8 {mu}m and <1 vol% above 37 {mu}m. Filtration behavior of the current batch is expected to be near that of recent batches. SRNL recommends acceptance of this material. SRNL also recommends performing a statistical review of particle size data for the MST lots from this vendor to assess whether an improved material specification is appropriate.

  5. Fissile solubility and monosodium titanate loading tests

    SciTech Connect

    Hobbs, D.T.; Fleischman, S.D.

    1993-02-12

    The solubilities of plutonium and uranium have been determined for alkaline salt solutions having compositions which bound those which will be processed in the In-Tank Precipitation (ITP) process. Loadings of plutonium and uranium onto monosodium titanate (MST) have been determined at temperatures bounding those expected to occur during ITP and using a salt solution which was determined to have the maximum solubility for uranium and plutonium. Fissile loadings increase with decreasing amounts of MST in contact with the salt solutions saturated in plutonium and uranium. At MST concentrations bounding those which are planned for the ITP process, expressions for the maximum loadings (wt %) are determined to be 0.29 - 0.20x[MST] for plutonium and 1.8 - 0.29x[MST] for uranium, where [MST] is the concentration of MST in grams/liter. These expressions are valid over the range of MST concentrations from 0.05 to 0.51 g/L and temperatures of 17{degrees}--74{degrees}C. These loadings are below the individual infinitely safe limits for plutonium and uranium. Additional confirmatory experiments are planned to verify the effects of temperature and multiple contacts of the MST with fresh salt solution on the fissile loadings.

  6. Fissile solubility and monosodium titanate loading tests

    SciTech Connect

    Hobbs, D.T.; Fleischman, S.D.

    1993-02-12

    The solubilities of plutonium and uranium have been determined for alkaline salt solutions having compositions which bound those which will be processed in the In-Tank Precipitation (ITP) process. Loadings of plutonium and uranium onto monosodium titanate (MST) have been determined at temperatures bounding those expected to occur during ITP and using a salt solution which was determined to have the maximum solubility for uranium and plutonium. Fissile loadings increase with decreasing amounts of MST in contact with the salt solutions saturated in plutonium and uranium. At MST concentrations bounding those which are planned for the ITP process, expressions for the maximum loadings (wt %) are determined to be 0.29 - 0.20x[MST] for plutonium and 1.8 - 0.29x[MST] for uranium, where [MST] is the concentration of MST in grams/liter. These expressions are valid over the range of MST concentrations from 0.05 to 0.51 g/L and temperatures of 17[degrees]--74[degrees]C. These loadings are below the individual infinitely safe limits for plutonium and uranium. Additional confirmatory experiments are planned to verify the effects of temperature and multiple contacts of the MST with fresh salt solution on the fissile loadings.

  7. [Luminol-enhanced chemiluminescence of rabbit polymorphonuclear leukocytes: the nature of oxidants that directly induce luminol oxidation].

    PubMed

    Roshchupkin, D I; Belakina, N S; Murina, M A

    2006-01-01

    The present work deals with the reaction pathways, including the formation of hydroxyl radicals and chloroamines, which lead to luminol chemiluminescence caused by hypochlorite generation in a suspension of stimulated rabbit polymorphnonuclear leukocyte. Luminol-enhanced (0.02 mM) chemiluminescence of leukocytes stimulated by phorbol 12-myristate 13-acetate does not change in the presence of dimethyl sulfoxide at moderate concentrations (0.02-2.6 mM) at which it must show the specific ability to scavenge hydroxyl radicals. It suggests that no generation of hydroxyl radical with the participation of hypochlorite and superoxide anion takes place after the stimulation of polymorphnonuclear leukocytes. A high dimethyl sulfoxide concentrations (260 mM) a significant fall in chemiluminescence intensity, due to direct interaction of the scavenger with hypochlorite, is observed. Chemiluminescence intensity rose if luminol was added to a leukocyte suspension preliminary stimulated for 10 min. The effect results from the accumulation of hydrogen peroxide but not chloroamines. Exogenic amino acids and taurin at high concentrations (3-15 mM) weaken the chemiluminescence. The data obtained suggest that chemiluminescence in the system studied results predominantly from the direct initial reaction of hypochlorite with luminol. The chemiluminescence intensity is enhanced by hydrogen peroxide via the oxidation of luminol oxidation products.

  8. Increasing the specificity of the forensic luminol test for blood.

    PubMed

    Quickenden, T I; Cooper, P D

    2001-01-01

    It is shown that the presumptive luminol chemiluminescence test for the presence of traces of blood can be made more determinative by measuring the peak emission wavelength of the luminol chemiluminescence. When sprayed onto a surface containing traces of human haemoglobin, a 1 g/L solution of aqueous luminol containing 7 g/L sodium perborate gives an emission peak at 455 +/- 2 nm, whereas the same mixture gives an emission peak at 430 +/- 3 nm when sprayed onto a surface containing traces of sodium hypochlorite (household bleach). This spectral difference can readily be determined using spectroscopic equipment that either scans the spectrum before significant luminescence decay occurs or corrects the spectrum for the effects of any decay. It was found that bovine haemoglobin and human haemoglobin showed no significant spectral differences. Copyright 2001 John Wiley & Sons, Ltd.

  9. Luminol-based bioluminescence imaging of mouse mammary tumors.

    PubMed

    Alshetaiwi, Hamad S; Balivada, Sivasai; Shrestha, Tej B; Pyle, Marla; Basel, Matthew T; Bossmann, Stefan H; Troyer, Deryl L

    2013-10-05

    Polymorphonuclear neutrophils (PMNs) are the most abundant circulating blood leukocytes. They are part of the innate immune system and provide a first line of defense by migrating toward areas of inflammation in response to chemical signals released from the site. Some solid tumors, such as breast cancer, also cause recruitment and activation of PMNs and release of myeloperoxidase. In this study, we demonstrate that administration of luminol to mice that have been transplanted with 4T1 mammary tumor cells permits the detection of myeloperoxidase activity, and consequently, the location of the tumor. Luminol allowed detection of activated PMNs only two days after cancer cell transplantation, even though tumors were not yet palpable. In conclusion, luminol-bioluminescence imaging (BLI) can provide a pathway towards detection of solid tumors at an early stage in preclinical tumor models. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Black and green tea - luminol false-negative bloodstains detection.

    PubMed

    Bancirova, Martina

    2012-06-01

    The antioxidant properties of black and green teas are well known. It is also possible to determine their antioxidant capacity by using a chemiluminscent method. This method is based on the measurement of the delay in the emission of light from the luminol reaction in the presence of the antioxidant. Bloodstains which are invisible to the naked eye can also be detected by luminol. Three common methods (detection using the Grodsky or Weber formulations and by Bluestar® Forensic latent bloodstain reagent) are based on the luminol chemiluminescence reaction. The bloodstains can be masked by drinks and/or foods containing antioxidants. The aim of this work was to compare the ability of black and green teas containing antioxidants to cause false negative results during chemiluminescent bloodstain detection.

  11. Sensitivity of the luminol test with blue denim.

    PubMed

    Middlestead, Caitlyn; Thornton, John

    2010-09-01

    An article appearing in this journal in 2000 suggested that the sensitivity of the luminol test performed on denim fabric is usually no greater than at a 1:100 dilution of blood. This study shows that the luminol test may be unambiguously interpreted at substantially greater dilutions of blood. In this study, four different types of denim were tested by spraying a swatch of fabric with a typical formulation of the luminol reagent. Testing was conducted of dilutions of blood up to 1:1000, all of which showed distinct chemiluminescence. Diluted blood was applied to denim material in the form of a random number. A successful test was obtained only when a "blind" observer, i.e., an observer who was uninformed of the number, correctly reported the number.

  12. Human bronchoalveolar lavage cells and luminol-dependent chemiluminescence.

    PubMed Central

    Williams, A J; Cole, P J

    1981-01-01

    Human bronchoalveolar lavage cells from several different disease states were examined by the technique of zymosan-stimulated, luminol-dependent chemiluminescence. Light production correlated well with polymorphonuclear leucocyte contamination of the alveolar macrophage suspension but not with lymphocyte contamination. Regression analysis indicated that human alveolar macrophages produce little if any luminol-dependent chemiluminescence. Further investigation of metabolic activity, using measurements of superoxide release, oxygen consumption, and lucigenin-dependent chemiluminescence, showed that "respiratory burst" activity in alveolar macrophages was stimulated by opsonised zymosan. PMID:6262385

  13. 40 CFR 721.3848 - Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, monosodium salt. 721.3848 Section 721.3848 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3848 Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt. (a... glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt (PMN P-00-469; CAS No. 141321-68-8) is subject...

  14. 40 CFR 721.3848 - Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, monosodium salt. 721.3848 Section 721.3848 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3848 Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt. (a... glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt (PMN P-00-469; CAS No. 141321-68-8) is subject...

  15. 40 CFR 721.3848 - Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, monosodium salt. 721.3848 Section 721.3848 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3848 Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt. (a... glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt (PMN P-00-469; CAS No. 141321-68-8) is subject...

  16. 40 CFR 721.3848 - Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, monosodium salt. 721.3848 Section 721.3848 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3848 Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt. (a... glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt (PMN P-00-469; CAS No. 141321-68-8) is subject...

  17. [Chemiluminescence of the polymorphonuclear leukocytes-luminol system in the presence of biogenic chloramines].

    PubMed

    Murina, M A; Belakina, N S; Roshchupkin, D I

    2004-01-01

    It was demonstrated that N-chlorphenylalanine and other chloramines strengthen sharply chemiluminescence in the polymorphonuclear leukocytes (PML)-luminol system without special activation of cells. The intensity of chemiluminescence is higher than the intensity of luminol solution emission induced by N-chlorphenylalanine. But it was nearly equal to chemiluminescence intensity of a mixture of luminol, N-chlorphenylalanine and 20-30 nM H2O2. The increase in chemiluminescence in the PML-luminol system in the presence of N-chlorphenylalanine is not related to PML activation but is the result of direct oxidation of luminol by N-chlorphenylalanine. Chloramine derivatives of amino acids and taurine at final concentrations of 0.01-0.1 mM do not suppress luminol chemiluminescence in suspension of PML stimulated by phorbol-12-myristate-13-acetate. At the same time, hypochlorite inhibits sharply luminol emission induced by stimulated cells.

  18. Enhancement of the luminol test by means of light amplification.

    PubMed

    Thornton, J I; Guarino, K; Rios, F G; Cashman, P J

    1986-01-01

    The type of device commonly referred to as a "starlight scope" will amplify available light by a factor of approximately 17 000. The use of this device will permit an image to be formed by exceedingly small amounts of blood when reacted with luminol reagent. Modification of the apparatus is necessary to permit focusing at short distances.

  19. A BODIPY-luminol chemiluminescent resonance energy-transfer (CRET) cassette for imaging of cellular superoxide.

    PubMed

    Bag, S; Tseng, J-C; Rochford, J

    2015-02-14

    Spectroscopic and in cellulo studies are here reported on the very first BODIPY-luminol chemiluminescent resonance energy-transfer (CRET) cassette where the luminol CL agent is covalently linked to the BODIPY energy-transfer acceptor in a molecular dyad. The efficiency of intramolecular CRET investigated for the BODIPY-luminol dyad was found to be 64% resulting in a dual emissive response. Successful in cellulo biochemiluminescence via CRET was achieved in PMA activated splenocytes.

  20. The phagocyte chemiluminescence paradox: luminol can act as an inhibitor of neutrophil NADPH-oxidase activity.

    PubMed

    Fäldt, J; Ridell, M; Karlsson, A; Dahlgren, C

    1999-01-01

    The chemiluminescence system amplified by luminol or isoluminol is a sensitive and widely used method for determination of respiratory burst products generated by the NADPH-oxidase in phagocytes. The present study shows that luminol, but not isoluminol, can inhibit the release of oxygen metabolites generated by human neutrophil NADPH-oxidase. The difference in structure between luminol and isoluminol (rendering luminol more lipophilic than isoluminol, and thereby membrane-permeable), is suggested to determine indirectly whether or not the molecule is inhibitory. Luminol was shown to have an increased inhibitory effect after preincubation of neutrophils on a surface of aggregated IgG, suggesting that the cells can be transferred from a 'luminol-insensitive' to a 'luminol-sensitive' state. Since luminol had no inhibitory effect in a cell-free NADPH-oxidase system, it is likely that it interferes with the signal transduction pathway, leading to assembly and/or activation of the oxidase. As a consequence of the present results, showing that luminol but not isoluminol can inhibit NADPH-oxidase activity, we suggest that isoluminol is used in future studies of superoxide anion release from phagocytes. Copyright 1999 John Wiley & Sons, Ltd.

  1. Detection of singlet oxygen yield from new photosensitizers using luminol

    NASA Astrophysics Data System (ADS)

    Sakai, Harumasa; Oppelaar, Hugo; Baas, Paul; Van Zandwijk, Nico; Stewart, Fiona A.

    1995-03-01

    For the application of photodynamic therapy and diagnosis many different photosensitizers have been developed. It is important to compare these photosensitizers for their activity. It is generally accepted that the most important mechanism of cell killing is via the production of singlet oxygen. We therefore performed basic studies to detect singlet oxygen using a luminol reaction. The relative singlet oxygen yields from 4 photosensitizers (Photofrin, ATX-S10, mTHPC and NPe6) were measured by the detection of luminol chemiluminescence at 445 nm wavelength in Menzel's buffer solution at pH 10.5. NPe6, ATX-S10 and mTHPC all showed singlet oxygen productive abilities. These photosensitizers are new promising photosensitizers. These results show a possibility of comparison of each photosensitizer.

  2. [Oxidation of luminol with peroxidase from royal palm leaves].

    PubMed

    Alpeeva, I S; Sakharov, I Iu

    2007-01-01

    We optimized the conditions for luminol oxidation by hydrogen peroxide in the presence of peroxidase (EC 1.11.1.7) from royal palm leaves (Roystonea regia). The pH range (8.3-8.6) corresponding to maximum chemiluminescence was similar for palm tree peroxidase and horseradish peroxidase. Variations in the concentration of the Tris buffer were accompanied by changes in chemiluminescence. Note that maximum chemiluminescence was observed in the 30 mM solution. The detection limit of the enzyme assay during luminol oxidation by hydrogen peroxide was 1 pM. The specific feature of palm tree peroxidase was the generation of a long-term chemiluminescent signal. In combination with the data on the high stability of palm tree peroxidase, our results indicate that this enzyme is promising for its use in analytical studies.

  3. Photodynamic action of some sensitizers by photooxidation of luminol

    NASA Astrophysics Data System (ADS)

    Wierrani, Franz; Kubin, Andreas; Loew, Hans Günter; Henry, Michael; Spängler, Babette; Bodner, Klaus; Grünberger, Werner; Ebermann, Robert; Alth, Gerhart

    2002-09-01

    We report the development of a novel simple experimental method which allows the comparison of new photosensitizers based on their production of reactive oxygen species. A high-performance liquid chromatography (HPLC) assay permits the monitoring of several substances (sensitizer, reactant and oxidized end product) simultaneously on a single chromatogram. Photoreactions were monitored throughout their course by the HPLC assay surveying the sensitizers' efficiency of singlet oxygen production by the oxidative decomposition of luminol. Several photosensitizers were tested: Rose Bengal, Methylene Blue, Protoporphyrin IX, Photosan III, Photofrin, Hypericin and Pseudohypericin. Additionally, photoreactions were monitored by a standard pO2 detection system. The measurements of the two detection methods were strongly correlated. Rose Bengal proved to be the most efficient photosensitizer, clearly decreasing the luminol concentration and causing a corresponding increase in aminophthalic acid. Our experiments show that when factors necessary for photochemical reactions are absent or are blocked (antioxidants), no reaction can be detected.

  4. Ultrasensitive electrochemiluminescence immunosensor based on luminol functionalized gold nanoparticle labeling.

    PubMed

    Tian, Dayong; Duan, Chunfeng; Wang, Wei; Cui, Hua

    2010-06-15

    An ultrasensitive electrochemiluminescence (ECL) immunosensor based on luminol functionalized gold nanoparticle (AuNP) labeling was developed using human immunoglobulin G (hIgG) as a model analyte. The primary antibody biotin-conjugated goat-anti-human IgG was first immobilized on a streptavidin coated AuNP modified electrode, then the antigen (human IgG) and the luminol functionalized AuNP-labeled second antibody were conjugated successively to form a sandwich-type immunocomplex, i.e. immunosensor. ECL was carried out with a double-step potential in carbonate buffer solution containing 1.0 mmol/L H(2)O(2). Since thousand of luminol molecules were coated on the surface of AuNPs to realize labeling of multiple molecules with CL activity at a single antibody and the amplification of AuNPs and biotin-streptavidin system was utilized, luminol ECL signal could be enhanced greatly, finally resulting in extremely high sensitivity. The ECL method shows a detection limit of 1.0 pg/mL (S/N=3) for hIgG, which is superior to all previously reported methods for the determination of hIgG. Moreover, the proposed method is also simple, stable, specific, and time-saving, avoiding the complicated stripping procedure during CL detection and the uncontrollable synthesis of irregular nanoparticles compared with other chemiluminescence immunoassay based on AuNP labeling. Additionally, the labeling procedure is also superior to that of other reported multilabeling strategies, such as Ru complex-encapsulated polymer microspheres, and most of Ru complex-encapsulated liposomes in simplicity, stability, labeling property and practical applicability. Finally, the proposed method has been successfully applied to the detection of hIgG in human serums.

  5. Comparison of chemiluminescence from luminol solution and luminol-TiO₂ suspension after illumination of a 355 nm pulse laser.

    PubMed

    Min, Lingyue; Chen, Xueming; Wu, Xing-Zheng

    2010-01-01

    Chemiluminescence (CL) from luminol solution and luminol-TiO₂ suspension after illumination of a 355 nm pulse laser is compared. Both the CL systems showed the CL spectra with maximum wavelength of 430 nm, suggesting that the emission was from the excite state of 3-aminophthalate ion. The TiO₂ photocatalytically induced luminol CL could be separately detected either when the pulse laser power was smaller than 0.15 mJ/pulse or a slit was placed beyond -2-2 mm in the vertical direction of the laser beam. The TiO₂ photocatalytically induced luminol CL intensity was linear to the laser power, while that of the 355 nm pulse laser-induced was nonlinear. A log-log plot between the 355 nm pulse laser-induced luminol CL intensity and laser power showed a near-linear regression fit with a slope of 2.11, suggesting that a two-photon absorption process of luminol was present in the 355 nm pulse laser-induced luminol CL. Adsorbed oxygen on the surface of TiO₂ seemed to greatly contribute to the photocatalytically induced CL. Copyright © 2010 John Wiley & Sons, Ltd.

  6. Pattern of formylmethionyl-leucyl-phenylalanine-induced luminol- and lucigenin-dependent chemiluminescence in human neutrophils.

    PubMed Central

    Dahlgren, C; Aniansson, H; Magnusson, K E

    1985-01-01

    The stimulation of neutrophils by formylmethionyl-leucyl-phenylalanine results in a bimodal luminol-dependent chemiluminescence pattern. We observed, however, only a single peak chemiluminescence pattern in the response to the peptide when we used lucigenin as an amplifying substance. We suggest that lucigenin, the larger molecule, (510 daltons; luminol is 177 daltons) only exerts an extracellular effect. PMID:3965405

  7. [The possibility for determining haptoglobin phenotypes in blood stains after treatment with a luminol solution].

    PubMed

    Alesho, N A; Guzheedov, V N; Dvorkin, A I

    1989-01-01

    The paper gives the results of tests for influence of luminol solution of different composition on detectability of haptoglobin fractions in the bloodstains of different ages. It was stated that alkaline luminol solutions reduce intensity of fractions and may hamper Hp phenotype determination especially in old stains.

  8. Electrochemiluminescence of luminol at the titanate nanotubes modified glassy carbon electrode.

    PubMed

    Xu, Guifang; Zeng, Xiaoxue; Lu, Shuangyan; Dai, Hong; Gong, Lingshan; Lin, Yanyu; Wang, Qingping; Tong, Yuejin; Chen, Guonan

    2013-01-01

    A new strategy for the construction of a sensitive and stable electrochemiluminescent platform based on titanate nanotubes (TNTs) and Nafion composite modified electrode for luminol is described, TNTs contained composite modified electrodes that showed some photocatalytic activity toward luminol electrochemiluminescence emission, and thus could dramatically enhance luminol light emission. This extremely sensitive and stable platform allowed a decrease of the experiment electrochemiluminescence luminol reagent. In addition, in luminol solution at low concentrations, we compared the capabilities of a bare glassy carbon electrode with the TNT composite modified electrode for hydrogen peroxide detection. The results indicated that compared with glassy carbon electrode this platform was extraordinarily sensitive to hydrogen peroxide. Therefore, by combining with an appropriate enzymatic reaction, this platform would be a sensitive matrix for many biomolecules.

  9. Luminol-amplified chemiluminescence detects mainly superoxide anion produced by human neutrophils

    PubMed Central

    Bedouhène, Samia; Moulti-Mati, Farida; Hurtado-Nedelec, Margarita; Dang, Pham My-Chan; El-Benna, Jamel

    2017-01-01

    Reactive oxygen species (ROS) are produced by numerous biological systems and by several phagocytes such as neutrophils and macrophages. ROS include mostly superoxide anion, hydrogen peroxide, singlet oxygen and hydroxyl radical, which are involved in a variety of biological processes such as immunity, inflammation, apoptosis and cell signaling. Thus, there is a need for a sensitive and reliable method to measure ROS. The luminol-amplified chemiluminescence technique is widely used to measure ROS production by neutrophils; however, it is unclear which ROS species are detected by this technique. In this study, we show that Xanthine/Xanthine oxidase (XXO), a known superoxide-producing system, stimulated a luminol-amplified chemiluminescence in the absence of horseradish peroxidase (HRPO), while the presence of HRPO enhanced the response. Both reactions were inhibited by superoxide dismutase (SOD), but not by catalase, confirming that superoxide anion, and not hydrogen peroxide, is the species oxidizing luminol to produce chemiluminescence. Glucose/Glucose oxidase (GGO), a known hydrogen peroxide-producing system, did not induce luminol-amplified chemiluminescence in the absence of HRPO; however, addition of HRPO resulted in a chemiluminescence response, which was inhibited by catalase, but not by SOD. Myeloperoxidase (MPO), isolated from human neutrophils, was also able to enhance the superoxide- and hydrogen peroxide-dependent luminol-amplified chemiluminescence. The production of ROS by stimulated human neutrophils was detected by luminol-amplified chemiluminescence, which was only partially inhibited by SOD and catalase. Interestingly, adding HRPO to stimulated neutrophils increased the luminol-amplified chemiluminescence, which was strongly inhibited by SOD, but not by catalase. These results show that (a) luminol-amplified chemiluminescence is able to detect superoxide anion in the absence of peroxidases, but not hydrogen peroxide; (b) in the presence of

  10. 21 CFR 184.1521 - Monosodium phosphate derivatives of mono- and diglycerides.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Monosodium phosphate derivatives of mono- and diglycerides. 184.1521 Section 184.1521 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Specific Substances Affirmed as GRAS § 184.1521 Monosodium phosphate derivatives of mono- and diglycerides...

  11. 21 CFR 184.1521 - Monosodium phosphate derivatives of mono- and diglycerides.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Monosodium phosphate derivatives of mono- and diglycerides. 184.1521 Section 184.1521 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1521 Monosodium phosphate...

  12. 21 CFR 184.1521 - Monosodium phosphate derivatives of mono- and diglycerides.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Monosodium phosphate derivatives of mono- and diglycerides. 184.1521 Section 184.1521 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1521 Monosodium phosphate...

  13. 21 CFR 184.1521 - Monosodium phosphate derivatives of mono- and diglycerides.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Monosodium phosphate derivatives of mono- and diglycerides. 184.1521 Section 184.1521 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1521 Monosodium phosphate...

  14. 21 CFR 184.1521 - Monosodium phosphate derivatives of mono- and diglycerides.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Monosodium phosphate derivatives of mono- and diglycerides. 184.1521 Section 184.1521 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1521 Monosodium phosphate...

  15. 40 CFR 721.3848 - Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Glycine, N-(carboxymethyl)-N-dodecyl... Specific Chemical Substances § 721.3848 Glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt. (a... glycine, N-(carboxymethyl)-N-dodecyl-, monosodium salt (PMN P-00-469; CAS No. 141321-68-8) is subject to...

  16. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Monosodium phosphate derivatives of mono- and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  17. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Monosodium phosphate derivatives of mono- and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  18. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Monosodium phosphate derivatives of mono- and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  19. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Monosodium phosphate derivatives of mono- and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  20. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Monosodium phosphate derivatives of mono- and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or...

  1. Monosodium glutamate and aspartame in perceived pain in fibromyalgia.

    PubMed

    Vellisca, María Y; Latorre, José I

    2014-07-01

    Our aim was to assess the effect of dietary elimination of monosodium glutamate (MSG) and aspartame on perceived pain in fibromyalgia. A total of 72 female patients with fibromyalgia were randomized to discontinuation of dietary MSG and aspartame (n = 36) or waiting list (n = 36). Patients were requested to rate their pain using a seven-point scale. Comparisons between both groups showed no significant differences on pain referred during the baseline or after the elimination of dietary MSG and aspartame. The discontinuation of dietary MSG and aspartame did not improve the symptoms of fibromyalgia.

  2. Effects of pH and Surfactant on the Ultrasound-Induced Chemiluminescence of Luminol

    NASA Astrophysics Data System (ADS)

    Miyoshi, Norio; Hatanaka, Shin-ichi; Yasui, Kyuichi; Mitome, Hideto; Fukuda, Masaru

    2001-06-01

    The pH dependence of the sonochemi-luminescence (SCL) of luminol at 141 kHz was investigated and compared to the effect of pH on its fluorescence emission intensity. From the fluorescence intensity, the pKa1* and the pKa2* values were determined to be 6.4 and 10.5 respectively, which was consistent with changes observed in the SCL intensity of luminol when the pH was varied. An inverse relationship was found to exist between the SCL and the fluorescence intensities against pH, i.e., the luminol SCL spectrum at pH=10.8 (mono-anionic form) had the same shape as the fluorescence emission spectra in acidic pH solutions, where luminol exists in either the mono-cationic or neutral form. The addition of an anionic surfactant, sodium dodecyl sulfate (SDS), significantly decreased the luminol SCL intensity at high pH@. It is proposed that the generation of a negative electric potential at the surface of cavitation bubbles effectively prevented the negatively charged form of luminol from approaching the bubbles, thereby inhibiting the reaction of luminol with OH radicals.

  3. Flow injection chemiluminescence analysis of phenolic compounds using the NCS-luminol system.

    PubMed

    Haghighi, Behzad; Dadashvand, Reza

    2006-03-01

    A flow injection system coupled with two simple and sensitive chemiluminescence (CL) methods is described for the determination of some phenolic compounds. The methods are based on the inhibition effects of the investigated phenols on the CL signal intensities of N-chlorosuccinimide-KI-luminol (NCS-KI-luminol) and NCS-luminol systems. The influences of the chemical and hydrodynamic parameters on the decrease in CL signal intensities of NCS-KI-luminol and NCS-luminol systems for hydroquinone, catechol, and resorcinol, serving as the model compounds of analyte, were studied in the flow injection mode of analysis. Under the selected conditions, the proposed CL systems were used for the determination of some phenolic compound and analytical characteristics of the systems including calibration equation, correlation coefficient, linear dynamic range, limit of detection, and sample throughput. The limits of detection for hydroquinone, catechol, and resorcinol were 0.002, 0.01, and 0.3 microM using the NCS-KI-luminol system; for the NCS-luminol system these were 0.01, 0.17, and 1.6 microM, respectively. The relative standard deviation for 10 repeated measurements of 0.04, 0.06, and 1 microM of hydroquinone, catechol, and resorcinol were 1.9, 1.4, and 2.0%, respectively, with the NCS-KI-luminol system; for 0.2, 0.5, and 4 microM of hydroquinone, catechol, and resorcinol these were 2.6, 2.2, and 3.7%, respectively, using the NCS-luminol system. The method was applied to the determination of catechol in known environmental water samples with a relative error of less than 6%. A possible reaction mechanism of the proposed CL system is discussed briefly.

  4. Research and development of a luminol-carbon monoxide flow system

    NASA Technical Reports Server (NTRS)

    Thomas, R. R.

    1977-01-01

    Adaption of the luminol-carbon monoxide injection system to a flowing type system is reported. Analysis of actual wastewater samples was carried out and revealed that bacteria can be associated with particles greater than 10 microns in size in samples such as mixed liquor. Research into the luminol reactive oxidation state indicates that oxidized iron porphyrins, cytochrome-c in particular, produce more luminol chemiluminescence than the reduced form. Correlation exists between the extent of porphyrin oxidation and relative chemiluminescence. In addition, the porphyrin nucleus is apparently destroyed under the current chemiluminescent reaction conditions.

  5. [Determination of I- by the ECL of luminol in neutral medium].

    PubMed

    Chu, Hai-Hong; Qi, Ying-Ying; Xu, Yang; Huang, Bing-Qiang; Tu, Yi-Feng

    2005-05-01

    Based on the studies of electrochemiluminescence(ECL) of luminol in neutral medium, the iodide would greatly sensitize the ECL of luminol. The ECL luminous intensity responded linearly to the concentration of iodide within the range of 3.8 x 10(-7) mol x L(-1) to 2.2 x 10(-6) mol x L(-1), and the detection limit is 4.0 x 10(-8) mol x L(-1). The mechanism of enhancement effect of iodide on luminol's ECL is also discussed. The experimental results showed that it was a free radical procedure.

  6. Assessment of monosodium glutamate (MSG) intake in a rural Thai community: questioning the methodological approach

    PubMed Central

    2013-01-01

    We examined the methodological approach to the assessment of monosodium glutamate intake. The high carbohydrate and low fat consumption characteristic of this study population would be conducive to the development of metabolic syndrome. However, anomalies in the assessment of dietary information limits conclusion to a causal link of monosodium glutamate to metabolic syndrome and overweight because the study lacks data on the main dietary patterns of consumption. Given the current paucity of data from human studies on monosodium glutamate intake and risk, more studies with robust methodology are required to assess causal links to disease. PMID:23890489

  7. Synthesis and fluorescence study of naphthalimide-coumarin, naphthalimide-luminol conjugates.

    PubMed

    Sheshashena Reddy, T; Ram Reddy, A

    2014-11-01

    Fluorescent naphthalimide-coumarin and naphthalimide-luminol conjugates were prepared by nucleophilic substitution reaction. The synthesized conjugates were characterized by (1)H-NMR, (13)C-NMR, mass and IR spectra. The absorption and fluorescence of these conjugates revealed that naphthalimide-luminol conjugates are more fluorescent than the naphthalimide-coumarin conjugates. In proton accepting DMSO solvent the fluorescence of the conjugates was quenched, while in proton donating ethanol solvent enhanced fluorescence was noticed. Based on the excitation maxima and fluorescence maxima it was found that in naphthalimide-coumarin conjugates coumarin acting as donor and naphthalimide acting as acceptor where as in naphthalimide-luminol conjugates naphthalimide acts as donor and luminol acts as acceptor.

  8. Silver nanoparticle-initiated chemiluminescence reaction of luminol-AgNO3 and its analytical application.

    PubMed

    Liu, Cui; Li, Baoxin

    2011-07-01

    Ag(+) has been regarded as an inert chemiluminescent oxidant. In this work, it was found that in the presence of silver nanoparticles (AgNPs), AgNO(3) could react with luminol to produce strong chemiluminescence (CL). The AgNPs with smaller size could initiate stronger CL emission. To investigate the CL mechanism of the AgNPs-luminol-AgNO(3) system, the UV-visible spectra and the CL spectrum of the CL system were obtained. The CL reaction mechanism involving catalysis was proposed. Compared with the reported nanoparticles-luminol-H(2)O(2) CL system, the AgNPs-luminol-AgNO(3) CL system has the advantages of low background and good stability. Moreover, the new CL system was used in immunoassay for IgG.

  9. Catalysis by manganese (III) 8-hydroxyquinolinates of the chemiluminescent reaction of luminol with hydrogen peroxide

    SciTech Connect

    Kalinichenko, I.E.; Matveeva, E.Y.; Pilipenko, A.T.

    1985-09-01

    This paper examines the kinetics of the reaction of luminol with H/sub 2/O/sub 2/ in the presence of Mn (III) 8-hydroxyquinolinate according to the data of measurements of the chemiluminescence intensity and the yield of light in this reaction. A reaction mechanism was proposed, providing for the oxidation of luminol by complexes of Mn (IV) that are formed in the decoposition of H/sub 2/O/sub 2/.

  10. Luminol-silver nitrate chemiluminescence enhancement induced by cobalt ferrite nanoparticles.

    PubMed

    Shi, Wenbing; Wang, Hui; Huang, Yuming

    2011-01-01

    CoFe(2)O(4) nanoparticles (NPs) could stimulate the weak chemiluminescence (CL) system of luminol and AgNO(3), resulting in a strong CL emission. The UV-visible spectra, X-ray photoelectron spectra and TEM images of the investigated system revealed that AgNO(3) was reduced by luminol to Ag in the presence of CoFe(2)O(4) NPs and the formed Ag covered the surface of CoFe(2)O(4) NPs, resulting in CoFe(2)O(4)-Ag core-shell nanoparticles. Investigation of the CL reaction kinetics demonstrated that the reaction among luminol, AgNO(3) and CoFe(2)O(4) NPs was fast at the beginning and slowed down later. The CL spectra of the luminol - AgNO(3) - CoFe(2)O(4) NPs system indicated that the luminophor was still an electronically excited 3-aminophthalate anion. A CL mechanism has been postulated. When the CoFe(2)O(4) NPs were injected into the mixture of luminol and AgNO(3), they catalyzed the reduction of AgNO(3) by luminol to produce luminol radicals and Ag, which immediately covered the CoFe(2)O(4) NPs to form CoFe(2)O(4)-Ag core-shell nanoparticles, and the luminol radicals reacted with the dissolved oxygen, leading to a strong CL emission. With the continuous deposition of Ag on the surface of CoFe(2)O(4) NPs, the catalytic activity of the core-shell nanoparticles was inhibited and a decrease in CL intensity was observed and also a slow growth of shell on the nanoparticles. Copyright © 2011 John Wiley & Sons, Ltd.

  11. Luminol-, isoluminol- and lucigenin-enhanced chemiluminescence of rat blood phagocytes stimulated with different activators.

    PubMed

    Pavelkova, Martina; Kubala, Lukas

    2004-01-01

    Luminol-, isoluminol- or lucigenin-enhanced chemiluminescence (CL) was used to measure the production of reactive oxygen species by rat blood leukocytes. Opsonized zymosan (OZ), phorbol-12-myristate-13-acetate (PMA), calcium ionophore A23187 (Ca-I) or N-formyl-Met-Leu-Phe (fMLP) were used as activators. The CL signal of isolated blood leukocytes decreased in rank order of luminol > isoluminol > lucigenin. The kinetic profiles of luminol- and isoluminol-enhanced CL were similar upon stimulation by each activator tested. The remarkably higher luminol and isoluminol CL responses were obtained after OZ stimulation when compared with other activators. However, when lucigenin was used, the PMA- and OZ-stimulated CL were comparable. The presence of plasma increased OZ-activated CL because of the enhanced phagocytosis of OZ. This was demonstrated by determining the phagocytosis of the fluorescent OZ using a flow cytometer. In contrast, the presence of plasma decreased PMA-activated CL, due to the antioxidant properties of plasma as determined by the CL method. As far as whole blood is concerned, only OZ activated luminol-enhanced CL was reliable. Blood volumes over 5 microL decreased CL activity due to the scavenging ability of erythrocytes. The results suggest that 0.5 microL whole blood is sufficient for routine luminol-enhanced CL analysis of whole blood oxidative burst in rats. Copyright 2004 John Wiley & Sons, Ltd.

  12. Enhanced chemiluminescence of the luminol-AgNO3 system by Ag nanoparticles.

    PubMed

    Li, Shifeng; Sun, Huimin; Wang, Dong; Hong, Jianguo; Tao, Shanjun; Yu, Haiyin; Wang, Xiuhua; Wei, Xianwen

    2012-01-01

    The oxidation reaction of luminol with AgNO(3) can produce chemiluminescence (CL) in the presence of silver nanoparticles (NPs) in alkaline solution. Based on the studies of UV-vis absorption spectra, photoluminescence (PL) spectra and CL spectra, a CL enhancement mechanism is proposed. The CL emission spectrum of the luminol-AgNO(3)-Ag NPs system indicated that the luminophore was still 3-aminophthalate. On injection of silver nanoparticles into the mixture of luminol and AgNO(3), they catalysed the reduction of AgNO(3) by luminol. The product luminol radicals reacted with the dissolved oxygen, to produce a strong CL emission. As a result, the CL intensity was substantially increased. Moreover, the influences of 18 amino acids, e.g. cystine, tyrosine and asparagine, and 25 organic compounds, including gallic acid, tannic acid and hydroquinone, on the luminol-AgNO(3)-Ag NPs CL system were studied by a flow-injection procedure, which led to an effective method for detecting these compounds. Copyright © 2011 John Wiley & Sons, Ltd.

  13. An evaluation of luminol formulations and their effect on DNA profiling.

    PubMed

    Patel, Gnyaneshwari; Hopwood, Andy

    2013-07-01

    Luminol is a presumptive test reagent used for the location of latent bloodstains. Various formulations are used by different forensic practitioners and commercial products are also widely available. There is little concurrence between authors with regards to the sensitivity limits of luminol which can vary significantly depending upon the substrate. We evaluated the sensitivity and stability of five different luminol formulations on a range of blood dilutions. All formulations showed an overall decrease in performance over 24 h though the effect was more gradual on a non-porous surface compared to porous. We found that BlueStar® Magnum showed the greatest sensitivity compared to other formulations and detected 50 μl of 1/100,000 blood dilutions on both porous and non-porous surfaces. Two formulations of luminol were selected based on the result of the sensitivity and stability study and were assessed for their impact on the DNA profiling process. There was a statistically significant improvement in DNA profile peak area from luminol-treated samples when compared to control samples of neat blood stains. However, at the weaker blood dilution of 1/1,000, the difference between control and luminol-treated samples was dependent on the substrate type with porous (fabric) samples showing a significant difference and non-porous (tile) swabbed samples requiring further work to conclusively ascertain the effect.

  14. The effect of luminol on presumptive tests and DNA analysis using the polymerase chain reaction.

    PubMed

    Gross, A M; Harris, K A; Kaldun, G L

    1999-07-01

    This study was designed to test the following factors involved with processing luminol treated bloodstained evidence: 1) The reactivity of other presumptive chemical color tests, phenolphthalin (PT) and tetramethylbenzidine (TMB), following the application of the light emitting luminol presumptive test. 2) The effect of different cleanings of various bloody substrates on the luminol test. 3) The effect of different cleanings of various bloody substrates on the ability to obtain DNA suitable for PCR testing. 4) The ability to extract DNA from luminol treated bloodstained substrates using three extraction techniques. 5) The effect of spraying washed and unwashed bloodstains on various substrates with luminol on the ability to correctly type the DNA using PCR. Our findings indicated that luminol did not adversely effect the PCR testing and did not interfere with the PT and TMB presumptive tests for blood. It was determined that the substrate and the method of cleaning were the major factors affecting DNA yield and the ability to type the bloodstains using PCR based technologies.

  15. What do we measure with luminol-, lucigenin- and penicillin-amplified chemiluminescence? 1. Investigations with hydrogen peroxide and sodium hypochlorite.

    PubMed

    Rost, M; Karge, E; Klinger, W

    1998-01-01

    Evidence is provided that the amplifiers luminol and lucigenin react with different reactive oxygen species (ROS), depending on the ROS-generating system used. H2O2 is used to produce calibration curves for luminol- and lucigenin-amplified chemiluminescence. With this chemiluminescence generator we characterized the specificity and sensitivity of luminol- and lucigenin-amplified chemiluminescence and also studied penicillin G, a known enhancer of luminol-amplified chemiluminescence. The combination of luminol and lucigenin in reciprocally changing concentrations is effective in an additive manner, but the weak amplifier penicillin increases luminol-amplified chemiluminescence distinctly more than in an additive manner in different combinations. Lucigenin-amplified chemiluminescence is increased by penicillin at about 1% of the optimum concentration of penicillin; increasing concentrations of penicillin are less and less effective. On the other hand, low lucigenin concentrations enhance penicillin-amplified chemiluminescence at optimum penicillin concentrations more than in an additive manner. Fe2+ does not alter luminol-, lucigenin- or penicillin-amplified chemiluminescence. Co2+ increases luminol-amplified chemiluminescence by a factor of 100. Lucigenin- and penicillin-amplified chemiluminescence are minimally enhanced by Co2+. Cu2+ enhances luminol-amplified chemiluminescence with increasing concentrations by a factor of 1000. Lucigenin-amplified chemiluminescence increases also by the factor of 1000, but the concentration-reaction curve is not as steep. NaOCl enhances H2O2/Fe(2+)-driven luminol-amplified chemiluminescence in a concentration-dependent manner by a factor of 10(4) (in the highest concentration of 10 mmol/L) and lucigenin amplified chemiluminescence only by a factor of about 25. Catalase (CAT) abolishes luminol-, lucigenin- and penicillin-amplified chemiluminescence completely, whereas superoxide dismutase (SOD) has no effect on luminol- or

  16. Ultrasensitive immunoassay based on a pseudobienzyme amplifying system of choline oxidase and luminol-reduced Pt@Au hybrid nanoflowers.

    PubMed

    Zhou, Ying; Zhuo, Ying; Liao, Ni; Chai, Yaqin; Yuan, Ruo

    2014-12-04

    A multi-functional luminol-reduced Pt@Au hybrid flower-like nanocomposite (luminol-Pt@AuNF) which not only acts as an efficient signal probe but also constitutes a pseudobienzyme amplifying system with choline oxidase (ChOx) was firstly synthesized and applied to the construction of a solid-state luminol electrochemiluminescence (ECL) immunosensor for cardiac troponin I (cTnI) detection.

  17. LEACHING OF TITANIUM FROM MONOSODIUM TITANATE AND MODIFIED MST

    SciTech Connect

    Taylor-Pashow, K.; Fondeur, F.; Fink, S.

    2012-08-01

    Analysis of a fouled coalescer and pre-filters from Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit (ARP/MCU) operations showed evidence of Ti containing solids. Based on these results a series of tests were planned to examine the extent of Ti leaching from monosodium titanate (MST) and modified monosodium titanate (mMST) in various solutions. The solutions tested included a series of salt solutions with varying free hydroxide concentrations, two sodium hydroxide concentrations, 9 wt % and 15 wt %, nitric and oxalic acid solutions. Overall, the amount of Ti leached from the MST and mMST was much greater in the acid solutions compared to the sodium hydroxide or salt solutions, which is consistent with the expected trend. The leaching data also showed that increasing hydroxide concentration, whether pure NaOH solution used for filter cleaning in ARP or the waste salt solution, increased the amount of Ti leached from both the MST and mMST. For the respective nominal contact times with the MST solids - for filter cleaning or the normal filter operation, the dissolved Ti concentrations are comparable suggesting either cause may contribute to the increased Ti fouling on the MCU coalescers. Tests showed that Ti containing solids could be precipitated from solution after the addition of scrub acid and a decrease in temperature similar to expected in MCU operations. FTIR analysis of these solids showed some similarity to the solids observed on the fouled coalescer and pre-filters. Although only a cursory study, this information suggests that the practice of increasing free hydroxide in feed solutions to MCU as a mitigation to aluminosilicate formation may be offset by the impact of formation of Ti solids in the overall process. Additional consideration of this finding from MCU and SWPF operation is warranted.

  18. 78 FR 74115 - Monosodium Glutamate From the People's Republic of China and the Republic of Indonesia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-10

    ... Indonesia: Postponement of Preliminary Determination in the Countervailing Duty Investigations AGENCY... (PRC)); Nicholas Czajkowski at (202) 482- 1395 (the Republic of Indonesia (Indonesia)), AD/CVD... investigations of monosodium glutamate from Indonesia and the PRC.\\1\\ Currently, the preliminary determinations...

  19. Morphological characteristics of monosodium urate: a transmission electron microscopic study of intact natural and synthetic crystals.

    PubMed Central

    Paul, H; Reginato, A J; Schumacher, H R

    1983-01-01

    Transmission electron microscopic studies of synthetic and natural monosodium urate crystals dried on formvar coated grids showed identical internal structures in all crystals. At higher magnification the crystals' surface showed angular or wavy irregularities, and more rarely some crystals appeared to have other tiny crystals on the surface. Protein-like surface coating was not observed except in crystals from one asymptomatic patient in whom synovial fluid was loaded with monosodium urate crystals, but no inflammatory cells were present. Heated synthetic monosodium urate crystals retained the ultrastructural characteristics in their interior but they lost their needle or rod-like shape. Transmission electron microscopic study of monosodium urate crystals dried on formvar coated grids provides a quick method of investigating crystal ultrastructure. Images PMID:6830327

  20. Morphological characteristics of monosodium urate: a transmission electron microscopic study of intact natural and synthetic crystals.

    PubMed

    Paul, H; Reginato, A J; Schumacher, H R

    1983-02-01

    Transmission electron microscopic studies of synthetic and natural monosodium urate crystals dried on formvar coated grids showed identical internal structures in all crystals. At higher magnification the crystals' surface showed angular or wavy irregularities, and more rarely some crystals appeared to have other tiny crystals on the surface. Protein-like surface coating was not observed except in crystals from one asymptomatic patient in whom synovial fluid was loaded with monosodium urate crystals, but no inflammatory cells were present. Heated synthetic monosodium urate crystals retained the ultrastructural characteristics in their interior but they lost their needle or rod-like shape. Transmission electron microscopic study of monosodium urate crystals dried on formvar coated grids provides a quick method of investigating crystal ultrastructure.

  1. Luminol-labeled gold nanoparticles for ultrasensitive chemiluminescence-based chemical analyses.

    PubMed

    Syed, Lateef U; Swisher, Luxi Zhang; Huff, Hannah; Rochford, Caitlin; Wang, Fengli; Liu, Jianwei; Wu, Judy; Richter, Mark; Balivada, Sivasai; Troyer, Deryl; Li, Jun

    2013-10-07

    We report a study on chemiluminescence-based chemical analyses using luminol molecules covalently attached to 10 nm diameter gold nanoparticles (GNPs). Chemiluminescence (CL) has been systematically studied under two schemes by varying the concentrations of luminol-labeled GNPs and [Fe(CN)6](3-) catalyst, respectively. The CL signal of luminol-labeled GNPs is enhanced by 5 to 10 times compared to the bulk luminol solutions of the same concentration. The log-log plot of the CL signal versus the number of luminol-labeled GNPs suspended in a standard 96-well plate shows two characteristic linear curves with distinct slopes across eight orders of magnitude variation in the GNP quantity (from 1.82 × 10(2) to 1.82 × 10(10) GNPs per well). The detection limit represented by the cross-point of these two curves can reach down to ~6.1 × 10(5) GNPs per well (corresponding to 1.0 × 10(-14) M GNP and 2.4 × 10(-11) M equivalent luminol concentration). The attachment of luminol molecules to GNP nano-carriers allows a large amount of luminol to be placed in a greatly reduced volume (or area) toward developing miniaturized CL sensors. We have demonstrated this by preloading dried luminol-labeled GNPs in homemade microwell arrays (with a volume of ~12 μL per well). A linear log-log curve can be obtained across the full range from 1 × 10(3) to 1 × 10(10) GNPs per microwell. The CL signal was detectable with as few as ~1000 GNPs. We have further applied this microwell method to the detection of highly diluted blood samples, in both intact and lysed forms, which releases Fe(3+)-containing hemoglobin to catalyze luminol CL. The lysed blood sample can be detected even after a 10(8) fold dilution (corresponding to ~0.18 cells per well). This ultrasensitive CL detection method may be readily adapted for developing various miniaturized multiplex biosensors for rapid chemical/biochemical analyses.

  2. Carbon dioxide effects on luminol and 1,10-phenanthroline chemiluminescence.

    PubMed

    Xiao, Caibin; Palmer, Donald A; Wesolowski, David J; Lovitz, Sara B; King, D Whitney

    2002-05-01

    Luminol and 1,10-phenanthroline are widely used chemiluminescent (CL) reagents for the analysis of a wide range of metals and inorganic and organic complexes. While the fundamental mechanism for luminol and 1,10-phenantholine chemiluminescence is understood, the analytical application of these reagents is largely empirical and often poorly described mechanistically. For example, CL signals observed from metal-luminol systems are strongly dependent on the pH of the sample, even though the final pH of the reaction mixture is controlled to a narrow range by a buffer. Other investigators report significant changes in CL signal due to freshness and the acidity of reagents. Our work shows that many of these effects are due to dissolved CO2 present or formed in the analytical system. The hypothesis that carbon dioxide plays a pivotal role in enhancing luminol CL is supported by direct manipulation of CO2(aq) concentrations by the addition of CO2(g) or carbonic anhydrase. In contrast, Cu(II) analysis using the CL reagent 1,10-phenanthroline is completely quenched in the presence of CO2(aq). A plausible mechanism for these observations involves the reaction between superoxide, produced in these analytical systems, and CO2(aq) to form the peroxycarbonate radical, *C04-. The formation of *CO4- has very important analytical implications since this species appears to enhance or quench the CL signal from luminol and 1,10-phenanthroline, respectively.

  3. Study on the chemiluminescence behavior of bovine serum albumin with luminol and its analytical application

    NASA Astrophysics Data System (ADS)

    Tan, Xijuan; Song, Zhenghua; Chen, Donghua; Wang, Zhuming

    2011-06-01

    In this paper, the luminescence behavior of bovine serum albumin (BSA) and luminol was first studied by flow injection chemiluminescence (CL). It was found that the hyperchromic effect of luminol in the presence of BSA led to the acceleration of the electrons transferring rate of excited 3-aminophthalate, which greatly enhanced the CL intensity of luminol/dissolved oxygen reaction. The increments of CL intensity were proportional to the concentrations of BSA with a linear range from 0.01 to 7 nmol L -1. It was also found that azithromycin could inhibit the CL intensity of luminol/BSA reaction. The decrements of CL intensity were logarithm over the concentrations of azithromycin ranging from 0.1 to 700 ng mL -1. At a flow rate of 2.0 mL min -1, a complete analytical process, which included sampling and washing, could be performed within 30 s with relative standard deviations of less than 3.1%. This proposed method was successfully applied in assaying azithromycin in pharmaceutical and human serum samples with recoveries from 91.0 to 104.3%. The possible luminescence mechanism of luminol/BSA/azithromycin reaction was discussed in detail by CL, UV and fluorescence methods.

  4. The effect of electrode material on the electrogenerated chemiluminescence of luminol

    SciTech Connect

    Vitt, J.E.; Johnson, D.C. ); Engstrom, R.C. )

    1991-06-01

    This paper reports on the oxidation of luminol and its concomitant electrogenerated chemiluminescence (ECL) which were studied at several electrode materials by voltammetry and chronoamperometry. The ECL intensity (I{sub ECL}) was inversely related to the activity of the electrodes. The lowest I{sub ECL}) was measured when luminol was oxidized to 3-aminophthalate (n {approx equal}4 eq mol{sup {minus}1}) at a nearly mass-transport limited rate at glassy carbon. The ECL kinetics were studied and the order of the reaction with respect to luminol was 3/2 at concentrations to ca. 1 mM when O{sub 2} was the coreactant. In the presence of H{sub 2}O{sub 2}, the ECL reaction was first order with respect to luminol. A reaction mechanism is proposed that is consistent with the inetic data and the inverse relationship between electrode activity and I{sub ECL}. The implications of these results are discussed with respect to imaging the spatial distribution of current density at electrode surfaces, including that of PbO{sub 2} films activated by adsorbed Bi(V). A value of 6.6 {times} 10{sup {minus}6} cm{sup 2} s{sup {minus}1} was determined for the diffusion coefficient of luminol in 0.1M NaOH.

  5. Study on the chemiluminescence behavior of bovine serum albumin with luminol and its analytical application.

    PubMed

    Tan, Xijuan; Song, Zhenghua; Chen, Donghua; Wang, Zhuming

    2011-06-01

    In this paper, the luminescence behavior of bovine serum albumin (BSA) and luminol was first studied by flow injection chemiluminescence (CL). It was found that the hyperchromic effect of luminol in the presence of BSA led to the acceleration of the electrons transferring rate of excited 3-aminophthalate, which greatly enhanced the CL intensity of luminol/dissolved oxygen reaction. The increments of CL intensity were proportional to the concentrations of BSA with a linear range from 0.01 to 7 nmol L(-1). It was also found that azithromycin could inhibit the CL intensity of luminol/BSA reaction. The decrements of CL intensity were logarithm over the concentrations of azithromycin ranging from 0.1 to 700 ng mL(-1). At a flow rate of 2.0 mL min(-1), a complete analytical process, which included sampling and washing, could be performed within 30s with relative standard deviations of less than 3.1%. This proposed method was successfully applied in assaying azithromycin in pharmaceutical and human serum samples with recoveries from 91.0 to 104.3%. The possible luminescence mechanism of luminol/BSA/azithromycin reaction was discussed in detail by CL, UV and fluorescence methods. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Gold Triangular Nanoprisms and Nanodecahedra: Synthesis and Interaction Studies with Luminol toward Biosensor Applications.

    PubMed

    Naveenraj, Selvaraj; Mangalaraja, Ramalinga Viswanathan; Wu, Jerry J; Asiri, Abdullah M; Anandan, Sambandam

    2016-11-15

    Gold triangular nanoprisms and nanodecahedra (pentagonal bipyramids) were synthesized in the absence and presence of nanoseeds by a simple solvothermal synthesis through the reduction of Auric Chloride (HAuCl4) with poly(vinylpyrrolidone) (PVP) in N,N-dimethylformamide (DMF), respectively. These gold nanoparticles exhibit two plasmon resonance bands. The interaction of these gold nanoparticles with luminol was investigated using UV-vis and fluorescence spectroscopy since hefty number of environmental and biological sensors are based on the combination of luminol and gold nanoparticles. The gold nanoparticles quenches the fluorescence of luminol through a static quenching mechanism, i.e., ground state complex formation, which was confirmed by both absorption spectroscopy as well as time-resolved fluorescence spectroscopy. The Stern-Volmer quenching constant and the effective quenching constant determine that gold nanodecahedra has more interaction with luminol than that of triangular gold nanoprisms. The distance between the gold nanoparticles and luminol, calculated using FRET theory, is less than 8 nm, which indicates efficient energy transfer during interaction. These results are expected to be useful for the development of novel sensors.

  7. Effect of oxygen abstraction on the peroxidase-luminol-perborate system: relevance to the HRP enhanced chemiluminescence mechanism.

    PubMed

    Cercek, B; Cercek, B; Roby, K; Cercek, L

    1994-01-01

    Abstraction of oxygen from the HRP enhanced chemiluminescence system has no significant effect on the chemiluminescence generated. It is, therefore, proposed that in the peroxidase-luminol-perborate system at pH 7.3, chemiluminescence is generated by a direct reaction of diazaquinones with hydrogen peroxide and not, as generally assumed, from the reaction of luminol radicals with the molecular oxygen.

  8. Luminol chemiluminescence and active oxygen generation by activated neutrophils.

    PubMed

    Takahashi, R; Edashige, K; Sato, E F; Inoue, M; Matsuno, T; Utsumi, K

    1991-03-01

    Upon stimulation by various ligands and membrane perturbers, neutrophils produce various active oxygen species. Since luminol chemiluminescence (LCL) in neutrophils can be blocked by azide, an inhibitor of myeloperoxidase, LCL has been believed to reflect mainly the myeloperoxidase-catalyzed reaction. When cells were stimulated by formyl-methionyl-leucyl-phenylalanine, LCL was strongly inhibited by superoxide dismutase (SOD) and uric acid, a scavenger for hydroxy radical (.OH) and singlet oxygen, whereas it was stimulated by azide. LCL was also inhibited by .OH scavengers, such as mannitol, ethanol, and dimethylsulfoxide. However, when stimulated by phorbol myristate acetate or opsonized zymosan, LCL was strongly inhibited by azide but not by uric acid, and the inhibitory action of SOD was low. Thus, the qualitative and quantitative aspects of reactive oxygen generation by activated neutrophils differ significantly from one ligand to another. These results suggest that the metabolic fate of active oxygens in neutrophils and, hence, their effect on microorganisms and the surrounding tissues might differ depending on the stimulus.

  9. Metabolism and disposition of luminol in the rat.

    PubMed

    Sanders, J M; Chen, L J; Burka, L T; Matthews, H B

    2000-03-01

    1. The metabolism and disposition of Luminol (LMN, 3-aminophthalhydrazide), a widely used forensic and laboratory reagent that chemiluminesses upon oxidation, was determined as part of its overall toxicological characterization. 2. Radiolabelled LMN was well absorbed, metabolized and excreted following p.o. administration of a range of doses. About 90% of the total dose was recovered within 24 h of administration in urine in the form of two metabolites identified as LMN N8-glucuronide and LMN N8-sulphamic acid. 3-Aminophthalic acid, the oxidative product of LMN in the light-emitting reaction, was apparently not formed in vivo. 3. Metabolism and disposition of an i.v. administered dose was similar to that following gavage. Little or no LMN-derived radioactivity was present in tissue within 12 h post-dosing. Excretion of radioactivity in bile following i.v. injection was minimal (approximately 8% of the total dose in 6 h) and consisted of the same urinary-excreted glucuronide and sulphate conjugates. 4. LMN was not absorbed dermally in rat, potentially a major route of exposure to human. If the fate of LMN is similar between species, this compound should have little potential for either dermal absorption, bioaccumulation in tissues following other routes of exposure or chronic toxicity in humans.

  10. Capillary gas chromatographic analysis of pans with luminol chemilumnescent detection

    SciTech Connect

    Gaffney, J.; Bornick, R.; Chen, Yu-Harn; Marley, N.

    1996-12-31

    Peroxyacyl nitrates (PANs) are important air pollutants in tropospheric chemistry. PANs are known to be potent phytotoxins at low ppb concentrations and are lachrymators. They can also transport the more reactive nitrogen dioxide long distances, because they are in equilibrium with that NO{sub x} species. Since PANs are trapped peroxyradicals, they are a direct measure of the peroxyradical levels and the of {open_quotes}photochemical age{close_quotes} of an air parcel. The PANs are typically measured in the atmosphere by using electron capture detection methods. These methods suffer from large background signals and detector responses to oxygen and water vapor. This paper describes the combination of a capillary gas chromatographic column with a modified luminol chemiluminescent nitrogen dioxide detector (Scintrex, Luminox) for rapid and sensitive detection of nitrogen dioxide, peroxyacetyl nitrate, peroxypropionyl nitrate, and peroxybutyryl nitrate. Detection limits for this approach in the low tens of parts per trillion have been observed with total analysis times of less than three minutes. We will discuss the potential application of this method to other compounds, particularly, organonitrates, in a pyrolysis system and/or with ozone addition to the sampling streams.

  11. Adsorption of biometals to monosodium titanate in biological environments

    SciTech Connect

    HOBBS, D.T.; MESSER, R. L. W.; LEWIS, J. B.; CLICK, D. R. LOCKWOOD, P. E.; WATAHA, J. C.

    2005-06-06

    Monosodium titanate (MST) is an inorganic sorbent/ion exchanger developed for the removal of radionuclides from nuclear wastes. We investigated the ability of MST to bind Cd(II), Hg(II), or Au(III) to establish the utility of MST for applications in environmental decontamination or medical therapy (drug delivery). Adsorption isotherms for MST were determined at pH 7-7.5 in water or phosphate-buffered saline. The extent of metal binding was determined spectroscopically by measuring the concentrations of the metals in solution before and after contact with the MST. Cytotoxic responses to MST were assessed using THP1 monocytes and succinate dehydrogenase activity. Monocytic activation by MST was assessed by TNF{alpha} secretion (ELISA) with or without lipopolysaccharide (LPS) activation. MST sorbed Cd(II), Hg(II), and Au(III) under conditions similar to that in physiological systems. MST exhibited the highest affinity for Cd(II) followed by Hg(II) and Au (III). MST (up to 100 mg/L) exhibited only minor (< 25% suppression of succinate dehydrogenase) cytotoxicity and did not trigger TNF{alpha} secretion nor modulate LPS-induced TNF{alpha} secretion from monocytes. MST exhibits high affinity for biometals with no significant biological liabilities in these introductory studies. MST deserves further scrutiny as a substance with the capacity to decontaminate biological environments or deliver metals in a controlled fashion.

  12. Reduction of sodium content in spicy soups using monosodium glutamate

    PubMed Central

    Jinap, Selamat; Hajeb, Parvaneh; Karim, Roslina; Norliana, Sarian; Yibadatihan, Simayi; Abdul-Kadir, Razak

    2016-01-01

    Background Excessive dietary sodium intake causes several diseases, such as hypertension, cardiovascular and renal disease, etc. Hence, reducing sodium intake has been highly recommended. In this study the effect of monosodium glutamate (MSG), as an umami substance, on saltiness and sodium reduction was investigated. Methods and Results The trained panellists were presented with basic spicy soups (curry chicken and chili chicken) containing different amounts of sodium chloride (NaCl) (0–1.2%) and MSG (0–1.2%). They tasted the optimum concentrations of NaCl and MSG for the two spicy soups and the overall acceptability were 0.8% and 0.7%, respectively. There was no significant effect of spiciness level on the saltiness and umami taste of both soups. The optimum levels of combined NaCl and MSG for overall acceptance in the chili and curry soups were 0.3% and 0.7%, respectively. The results showed that with the addition of MSG, it is possible to reduce sodium intake without changing the overall acceptability of the spicy soup. A 32.5% reduction in sodium level is made feasible by adding 0.7% MSG to the spicy soups. Conclusions This study suggests that low-sodium soups can be developed by the addition of appropriate amounts of MSG, while maintaining the acceptability of the spicy soups. It was also proven that it is feasible to reduce sodium intake by replacing NaCl with MSG. PMID:27356909

  13. Flavor preferences conditioned by intragastric monosodium glutamate in mice.

    PubMed

    Ackroff, Karen; Sclafani, Anthony

    2013-11-01

    The consumption of monosodium glutamate (MSG) solutions has been shown to reinforce preferences for MSG and for MSG-paired flavors in mice. These effects appear to have a strong postoral component, such that MSG detected in the gut is associated with concurrently consumed flavors. Two experiments investigated postoral MSG reward by infusing 400mM MSG intragastrically (IG) to C57BL/6 mice as they consumed a conditioned stimulus (CS+) flavor. An alternate CS- flavor was paired with IG water. In Experiment 1, the grape and cherry CS flavors were unsweetened, and intakes and preferences for the CS+ flavor were modest. Experiment 2 attempted to generate stronger preferences by adding 0.05% saccharin to the CS flavors. Sweet taste did enhance intakes during training and testing but did not significantly increase percent CS+ intake or persistence of the preference. However, only conditioning with the sweet CS+ resulted in the mice expressing a preference for oral MSG in an initial choice test with water. These findings extend recent studies demonstrating postoral MSG conditioning in rats.

  14. A method for counting monosodium urate crystals in synovial fluid.

    PubMed

    Montagna, P; Brizzolara, R; Ferrone, C; Cutolo, M; Paolino, S; Cimmino, M A

    2015-06-30

    This study was aimed to standardize the technique for counting monosodium urate (MSU) crystals in the synovial fluid (SF) of patients with gout. A total of 52 SF specimens were examined under a polarized light microscope. The amount of SF ranged between 0.1 and 45 mL (median 3 mL). MSU crystals were counted in four areas with the same size at 400x magnification. Cytological examination of the same specimens was also performed. Median leukocyte count was 400 cells/mm3 (range 50-14,000 cells/mm3), with a median percentage of polymorphonuclear leukocytes of 9% (range 0%-98%). Median crystal count was 179.5 (range 3-1600). Inter- reader and intra-reader agreement in crystal counting were good with a weighed k of 0.89 [95% confidence interval (CI) 0.85-0.94] and 0.89 (95% CI 0.84-0.93), respectively. Our data indicate that the SF MSU crystal count is a feasible and highly reliable technique.

  15. Reconsidering the effects of monosodium glutamate: a literature review.

    PubMed

    Freeman, Matthew

    2006-10-01

    This article reviews the literature from the past 40 years of research related to monosodium glutamate (MSG) and its ability to trigger a migraine headache, induce an asthma exacerbation, or evoke a constellation of symptoms described as the "Chinese restaurant syndrome." Literature retrieved by a search using PubMed, Medline, Lexis-Nexus, and Infotrac to review articles from the past 40 years. MSG has a widespread reputation for eliciting a variety of symptoms, ranging from headache to dry mouth to flushing. Since the first report of the so-called Chinese restaurant syndrome 40 years ago, clinical trials have failed to identify a consistent relationship between the consumption of MSG and the constellation of symptoms that comprise the syndrome. Furthermore, MSG has been described as a trigger for asthma and migraine headache exacerbations, but there are no consistent data to support this relationship. Although there have been reports of an MSG-sensitive subset of the population, this has not been demonstrated in placebo-controlled trials. Despite a widespread belief that MSG can elicit a headache, among other symptoms, there are no consistent clinical data to support this claim. Findings from the literature indicate that there is no consistent evidence to suggest that individuals may be uniquely sensitive to MSG. Nurse practitioners should therefore concentrate their efforts on advising patients of the nutritional pitfalls of some Chinese restaurant meals and to seek more consistently documented etiologies for symptoms such as headache, xerostomia, or flushing.

  16. Synthesis and characterization of monosodium urate (MSU) nano particles

    NASA Astrophysics Data System (ADS)

    Tank, Nirali S.; Rathod, K. R.; Parekh, B. B.; Parikh, K. D.; Joshi, M. J.

    2016-05-01

    In Gout the deposition of crystals of Monosodium Urate (MSU) in various connective tissues and joints occurs, which is very painful with immflamation. The deposition likely to begin with nano particles form and expected to grow in to micro-paricles and hence it is important to synthesize and characrterize MSU nano-particles. The MSU nano particles were synthesized by wet chemical method using NaOH and uric acid (C5H4N4O3) and then characterized by powder XRD, TEM, FT-IR and thermal analysis. From the powder XRD the triclinic structure was found and 40 nm average particle size was estimated by using Scherrer's formula. From TEM the particle size was found to be in the range of 20 to 60 nm. The FT-IR spectrum for the MSU nano particles confirmed the presence of O-H stretching, N-H stretching, N-H rocking, C = O, C = C Enol or Keto and C = N vibrations. The thermal analysis was carried out from room temperature to 900°C. With comparison to the bulk MSU the thermal stability of MSU nano particles was slightly higher and 1.5 water molecules were found to be associated with MSU nano particles. Present results are compared with the bulk MSU.

  17. Modulatory effects of non-steroidal anti-inflammatory drugs on the luminol and lucigenin amplified chemiluminescence of equine neutrophils.

    PubMed

    Benbarek, H; Ayad, A; Deby-Dupont, G; Boukraa, L; Serteyn, D

    2012-03-01

    The purpose of this study was to explore the potential modulation of equine neutrophil oxidative burst by a series of classical NSAIDs which was subsequently monitored by the luminol or lucigenin-enhanced chemiluminescence (CL) technique. A significant dose-dependent inhibition of the luminol CL was observed with the majority of investigated drugs. This inhibition was very significant for phenylbutazone and Indomethacin; while for aspirin, a higher concentration is required. The action of Ketoprofen was significant during the first 5 min and only when the concentration was above 1 mM. Indomethacin and acetylsalicylic acid result in an inhibition dose-dependent of luminol CL. On the other hand, the phenylbutazone showed an inhibiting effect when used either luminol or lucigenin though luminol is slightly better. When the ketoprofen is considered, an inhibiting effect of luminal CL was observed but less significant than the other NSAIDs investigated. The flunixin meglumine enhances strongly the CL.

  18. The assaying of haemoglobin using luminol chemiluminescence and its application to the dating of human skeletal remains.

    PubMed

    Creamer, J I; Buck, A M

    2009-01-01

    The luminol chemiluminescence reaction has, for some time, been used as a tool for the detection of haemoglobin at crime scenes. More recently, the luminol test has been suggested as a possible tool for estimating the post-mortem interval (PMI) of skeletal remains. The preliminary results from the following study indicate that the chemiluminescent luminol test is a relatively easy and economical method for distinguishing between remains of medico-legal (< or =100 years) and historical (>100 years) interest. The femur was the preferred bone for PMI measurements using the luminol test, due to its robustness and relative resistance to diagenesis. Initial results suggest that bone that was historical in nature, produced a demonstrably weaker reaction than that of medico-legal interest. These results suggest that the luminol test is a promising technique, albeit with some limitations, for the assessment of skeletal material that may be potentially of medico-legal interest.

  19. Kinetics simulation of luminol chemiluminescence based on quantitative analysis of photons generated in electrochemical oxidation.

    PubMed

    Koizumi, Yozo; Nosaka, Yoshio

    2013-08-22

    The kinetics of electrogenerated chemiluminescence (ECL) of luminol at a gold electrode in alkaline solution was investigated by measuring the absolute number of photons emitted in an integrating sphere. The ECL efficiency as the ratio of photon to electric charge was 0.0004 in cyclic voltammography and 0.0005 in chronoamperometry. By numerically solving the rate equations based on a diffusion layer model, the observed time profile of the luminescence intensity could be successfully simulated from the oxidation current of luminol in the chronoamperometry. In the simulation, the rate constant for the oxidation of luminol by superoxide radicals in alkaline solution was determined to be 6 × 10(5) M(-1) s(-1). The present methodology and the achievement could be widely applicable to various analytical techniques using chemiluminescence.

  20. Effect of the isocoumarin paepalantine on the luminol and lucigenin amplified chemiluminescence of rat neutrophils.

    PubMed

    Kitagawa, Rodrigo Rezende; Raddi, Maria Stella Gonçalves; Khalil, Najeh Maissar; Vilegas, Wagner; da Fonseca, Luiz Marcos

    2003-06-01

    Paepalantine (9,10-dihydroxy-5,7-dimethoxy-1H-naphto(2,3c)pyran-1-one), a natural isocoumarin isolated from the capitula of Paepalanthus bromelioides (Eriocaulaceae), was assessed for its effect on the respiratory burst (zymosan-stimulated luminol-enhanced chemiluminescence and PMA-stimulated lucigenin-enhanced chemiluminescence) of polymorphonuclear neutrophils in vitro. Special attention was devoted to establishing the IC(50) for neutrophils. Paepalantine was able to decrease luminol and lucigenin chemiluminescence, reflecting an inhibitory effect on the respiratory burst, with an ED(50) of 0.44+/-0.05 and 0.84+/-0.15 microg/ml, respectively. A cell-free system was performed with paepalantine on myeloperoxidase/H(2)O(2) and myeloperoxidase/H(2)O(2)/Cl(-) systems. Paepalantine inhibited luminol oxidation in both systems. This inhibition was related to the interaction of paepalantine-myeloperoxidase and its scavenger effect on HOCl.

  1. Menadione-catalyzed luminol chemiluminescent assay for viability of Mycobacterium bovis.

    PubMed

    Yamashoji, Shiro

    2002-01-01

    Stable luminol chemiluminescence was observed 10 min after the addition of menadione to a suspension of Mycobacterium bovis homogenized in Middlebrook 7H9 broth base including OADC enrichment. The chemiluminescence intensity was proportional to the absorbance of the bacterial suspension at 600 nm in a range of 0.005 to 0.15. Luminol chemiluminescence disappeared after 10 min incubation of M. bovis at over 60% of ethanol or 4 days of cultivation of M. bovis in the presence of 40 microg/ml of streptomycin. The bacterium showing the disappearance of chemiluminescence could not grow after being washed, suggesting that the inhibition concentration of the antimicrobials can be estimated on the basis of the disappearance of chemiluminescence. Menadione-catalyzed luminol chemiluminescent assay was rapid and sensitive in comparison to turbidimetry, tetrazolium (WST-8) reduction assay, and the assay using the Mycobacteria growth indicator tube (MGIT).

  2. Study on the electrochemiluminescent behavior of menadione sodium bisulfite in presence of luminol.

    PubMed

    Lin, Zhenyu; Chen, Jinhua; Chen, Guonan

    2007-07-31

    Menadione sodium bisulfite (MSB) is a stable water-soluble derivative of Vitamin K(3), which is found to be able to enhance the ECL of luminol at potential of 0.88 V in phosphate buffer solution. The conditions for the enhanced ECL, such as the selection of the type of buffer solution, applied potential mode, scanning rate, the effect of pH and concentration of luminol have been investigated in detail in this paper. Under the optimum conditions, the enhanced ECL intensity is linear with the concentration of MSB over a wide range, the detection limit for MSB is 3.0x10(-7)mol/L. The proposed method has been applied to determine the MSB in the commercial injection samples. A possible mechanism for the enhanced ECL of luminol by MSB has also been proposed.

  3. Correlation between hemin content and the chemiluminescent luminol reaction with bacteria.

    PubMed Central

    Ewetz, L; Thore, A

    1978-01-01

    Protohemin and covalently bound hemin were determined in eight aerobic bacterial strains. A good correlation between protohemin content and luminol reactivity was found. The ratio of luminol reaction to protohemin for the eight investigated strains was essentially identical to that of pure protohemin, 0.7 X 10(16) mV/mol. Covalently bound hemin contributed to the chemiluminescence to a minor extent only (0.7 X 10(14) mV/mol, in accordance with earlier observations of the lower reactivity of cytochrome c and related compounds. A difference in reaction kinetics of the luminol reaction with covalently bound hemin (slower reaction than protohemin) and protohemin was observed in vivo as well as in vitro. The phenomenon could be used to differentiate between strains with different hemin composition. PMID:216305

  4. Three dimethoxy-substituted luminol derivatives: A comparative study using theoretical method

    NASA Astrophysics Data System (ADS)

    Xue, Bingchun; Liu, Cuilan; Liu, Yanhong; Liu, Erbao

    2015-02-01

    In this research, geometrical optimisation, Mulliken charge, molecular electrostatic potential, and the frontier molecular orbitals of three dimethoxy-substituted luminol derivatives were investigated by ab initio, density functional, and Møller-Plesset perturbation theory with a 6-311G (d, p) basis set in gas phase, water, and dimethylsulphoxide solution. The UV-vis spectra were calculated by time dependent density functional theory method. The properties of derivatives were compared with luminol at a molecular level to investigate the change induced by the methoxy group. The three derivatives were also compared with the aim of predicting the order of chemiluminescent efficiency. The results showed that methoxy substitution significantly changed the electronic and spectral properties of luminol. Among three derivatives, structure 2 was suggested to have the highest chemiluminescent efficiency. The results may shed some light on the design and selection of chemiluminescent reagents.

  5. Luminol as in situ light source in meso-tetraphenylporphyrin-mediated photodynamic therapy.

    PubMed

    Huang, L; Chen, Ti-Chen; Lin, Feng-Huei

    2013-01-01

    The light sources used in current photodynamic therapy are mainly lasers or light emitting diodes, which are not suitable to treat large-volume tumors and those located in the inner body. To overcome the limitation, we propose an in situ light source to activate the photosensitizer and kill the cancer cells directly. In the present work, we use luminol as light source and meso-tetraphenylporphyrin as the photosensitizer. According to the results, cells incubated with meso-tetraphenylporphyrin, subsequently triggered by luminol, decreased significantly in assays including cell viability and cytotoxicity, while the other groups showed only minor differences. The flow cytometric and fluorescent microscopy analysis showed similar results as well. In the analysis of cell death pathway, cell shrinkage was noticed after photodynamic therapy treatment, which might refer to apoptosis. Briefly, we suggest that luminol is a promising light source in meso-tetraphenylporphyrin-mediated photodynamic therapy for its greater penetration depth and well matched emission wavelength.

  6. Stimulation of alveolar macrophages by mineral dusts in vitro: luminol-dependent chemiluminescence study

    SciTech Connect

    Vilim, V.; Wilhelm, J.; Brzak, P.; Hurych, J.

    1987-02-01

    Luminol-dependent chemiluminescence (CL) of normal (nonactivated) rabbit alveolar macrophages (AMs) was measured in suspension upon stimulation by various size fractions of one quartz dust sample or by various mineral dusts (quartz, corundum, anatas, and chrysotile asbestos as an example of fibrous dust). The CL-triggering capacity of the tested dusts was inhibited by their preincubation with autologous serum. The intensity of luminol-dependent CL induced by particulate dusts upon their action on AMs depended on the kind of dust, on the dust particle sizes, and on the ratio of the number of particles to the number of cells in a given suspension. The cytotoxicity and/or fibrogenicity of the dust and its capacity to trigger the luminol-dependent CL of nonadherent AMs were not directly correlated.

  7. Attempted cleaning of bloodstains and its effect on the forensic luminol test.

    PubMed

    Creamer, Jonathan I; Quickenden, Terence I; Crichton, Leah B; Robertson, Patrick; Ruhayel, Rasha A

    2005-01-01

    The forensic luminol test has long been valued for its ability to detect trace amounts of blood that are invisible to the naked eye. This is the first quantitative study to determine the effect on the luminol test when an attempt is made to clean bloodstained tiles with a known interfering catalyst (bleach). Tiles covered with either wet or dry blood were tested, and either water or sodium hypochlorite solution (bleach) was used to clean the tiles. As expected, the chemiluminescence intensity produced when luminol was applied generally decreased with the number of times that a tile was cleaned with water, until the chemiluminescence was neither visible nor detectable. However, when the tiles were cleaned with bleach there was an initial drop in chemiluminescence intensity, followed by a rise to a consistently high value, visibly indistinguishable from that of blood. Examination of bleach drying time suggested that any interfering effect becomes negligible after 8 h.

  8. A comparison of the presumptive luminol test for blood with four non-chemiluminescent forensic techniques.

    PubMed

    Webb, Joanne L; Creamer, Jonathan I; Quickenden, Terence I

    2006-01-01

    Presumptive blood detection tests are used by forensic investigators to detect trace amounts of blood or to investigate suspicious stains. Through the years, a number of articles have been published on the popular techniques of the day. However, there is no single paper that critiques and compares the five most common presumptive blood detection tests currently in use: luminol, phenolphthalein (Kastle-Meyer), leucomalachite green, Hemastix and the forensic light source. The present authors aimed to compare the above techniques with regard to their sensitivity, ease of use and safety. The luminol test was determined to be the most sensitive of the techniques, while Hemastix is a suitable alternative when the luminol test is not appropriate. Copyright 2006 John Wiley & Sons, Ltd.

  9. A method to determine quercetin by enhanced luminol electrogenerated chemiluminescence (ECL) and quercetin autoxidation.

    PubMed

    Lei, Rong; Xu, Xiao; Yu, Fei; Li, Na; Liu, Hu-Wei; Li, Kèan

    2008-05-30

    Quercetin greatly enhanced luminol electrochemiluminescence of quercetin in alkaline solution. When the concentration of luminol was 0.1 mol L(-1), the detection limit for quercetin was 2.0x10(-8) mol L(-1) with a linear range from 1.0x10(-7) to 2x10(-5) mol L(-1). The pH and buffer substantially affected ECL intensity. Quercetin was autoxidized in alkaline aqueous solution. The rate of autoxidation of quercetin in various pH buffers and borate concentrations were measured. Borate was found to inhibit quercetin autoxidation and compromise quercetin enhancement effect on luminol ECL to some extent. Two final autoxidation products were identified with LC-MS methods. Autoxidation process was associated with enhancement of ECL intensity. The ROS generated during quercetin autoxidation enhanced the ECL intensity.

  10. A label-free electrochemiluminescence aptasensor for thrombin based on novel assembly strategy of oligonucleotide and luminol functionalized gold nanoparticles.

    PubMed

    Li, Fang; Cui, Hua

    2013-01-15

    In the work, a label-free electrochemiluminescence (ECL) aptasensor for the sensitive and selective detection of thrombin was constructed based on target-induced direct ECL signal change by virtue of a novel assembly strategy of oligonucleotide and luminol functionalized gold nanoparticles (luminol-AuNPs). It is the first label-free ECL biosensor based on luminol and its analogs functionalized AuNPs. Streptavidin AuNPs coated with biotinylated DNA capture probe 1 (AuNPs-probe 1) were firstly assembled onto an gold electrode through 1,3-propanedithiol. Then luminol-AuNPs co-loaded with thiolated DNA capture probe 2 and thiolated thrombin binding aptamer (TBA) (luminol-AuNPs-probe 2/TBA) were assembled onto AuNPs-probe 1 modified electrode through the hybridization between capture probes 1 and 2. The luminol-AuNPs-probe 2/TBA acted as both molecule recognition probe and sensing interface. An Au/AuNPs/ds-DNA/luminol-AuNPs/TBA multilayer architecture was obtained. In the presence of target thrombin, TBA on the luminol-AuNPs could capture the thrombin onto the electrode surface, which produced a barrier for electro-transfer and influenced the electro-oxidation reaction of luminol, leading to a decrease in ECL intensity. The change of ECL intensity indirectly reflected the concentration of thrombin. Thus, the approach showed a high sensitivity and a wider linearity for the detection of thrombin in the range of 0.005-50nM with a detection limit of 1.7pM. This work reveals that luminol-AuNPs are ideal platform for label-free ECL bioassays. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Evaluation of the ocular penetration of topical alpha-luminol (Galavit®/GVT®).

    PubMed

    da Silva, Enry G; Gionfriddo, Juliet R; Hudachek, Susan F; Gustafson, Daniel L; Olea-Popelka, Francisco J; Scofield, Virgina L; Powell, Cynthia C; Hill, Ashley E

    2011-05-01

    Oxidative stress plays a major role in the pathogenesis of many neurodegenerative diseases. It has also been implicated as part of the pathogenic mechanisms in the development of glaucoma. Alpha-luminol has shown profound anti-inflammatory and antioxidant effects in both experimental animal and human clinical studies. The purpose of this pilot study was to investigate for the first time the ocular penetration of topical alpha-luminol. Nine animals were divided into three treated groups (three animals each; one drop OU/n = 18), each group receiving a different concentration of the eyedrop (0.5%, 1.5%, 2.5%). Aqueous humor and peripheral blood samples were obtained from each rabbit at three different timepoints (20 min, 4 h and 12 h). Samples were analyzed by means of high performance liquid chromatography and mass spectrometry; median values were compared. Alpha-luminol was found in the aqueous humor in all treated groups at all timepoints. At the 2nd and 3rd timepoints (4 h and 12 h), aqueous humor levels decreased significantly (P < 0.05) for two of the three dosages tested and it was not detectable in some eyes. The highest aqueous humor concentration of the drug was 272 ng/mL after 20 min (0.0217% of one drop, 2.5% group). Alpha-luminol was found in the vitreous in two animals, one in the 1.5% and another in the 2.5% group (16.4 and 21.5 ng/mL, respectively), at 12 h. Topically administered alpha-luminol readily penetrates into the anterior chamber and can penetrate into the vitreous chamber. Further investigation is warranted to better understand the intraocular pharmacokinetics of alpha-luminol. © 2011 American College of Veterinary Ophthalmologists.

  12. Detection of mitochondria-derived reactive oxygen species production by the chemilumigenic probes lucigenin and luminol.

    PubMed

    Li, Y; Zhu, H; Trush, M A

    1999-06-28

    Both lucigenin and luminol have widely been used as chemilumigenic probes for detecting reactive oxygen species (ROS) production by various cellular systems. Our laboratory has previously demonstrated that lucigenin localizes to the mitochondria of rat alveolar macrophages and that lucigenin-derived chemiluminescence (CL) appears to reflects superoxide O2(-.) production by mitochondria in the unstimulated macrophages. In this study, we further examined the ability of lucigenin- and luminol-derived CL to assess O2(-.) and H2O2 formation, respectively, by isolated intact mitochondria. Mitochondria were isolated from monocytes/macrophages differentiated from monoblastic ML-1 cells. Incubation of the substrate-supported mitochondria with lucigenin at non-redox cycling concentration produced lucigenin-derived CL. Luminol-derived CL was also elicited with substrate-supplemented mitochondria in the presence of horseradish peroxidase (HRP). The lucigenin-derived CL was diminished extensively by the membrane permeable superoxide dismutase (SOD) mimetics, 2,2,6, 6-tetramethylpiperidine-N-oxyl and Mn(III) tetrakis(1-methyl-4-pyridyl)porphyrin, but not by Cu,Zn-SOD. On the other hand, luminol-derived CL was not observed in the absence of HRP and was significantly inhibited by catalase. A spectrum of agents known to specifically affect mitochondrial respiration exhibited corresponding effects on both lucigenin- and luminol-derived CL. Taken together, our results demonstrate that with isolated mitochondria lucigenin-derived CL monitors intramitochondrial O2(-.) production by the mitochondrial electron transport chain, whereas the luminol-derived CL detects H2O2 released from the mitochondria. As such, use of both probes provides a comprehensive and clear assessment of ROS production by mitochondria.

  13. Enhanced effect of aggregated gold nanoparticles on luminol chemiluminescence system and its analytical application

    NASA Astrophysics Data System (ADS)

    Qi, Yingying; Li, Baoxin

    2013-07-01

    Some organic compounds containing groups of OH, NH2, or SH, which could induce the aggregation of gold nanoparticles (AuNPs), were observed to enhance effectively the luminol-H2O2-2.6 nm AuNPs CL system. It was found that the aggregation of AuNPs was an important effect factor for the catalytic activity of AuNPs on luminol CL system. The aggregated AuNPs could effectively enhance luminol CL signal compared with the dispersed one. The enhanced effect was closely related to the sizes of AuNPs. Among the studied AuNPs with seven sizes, 2.6 nm AuNPs had the greatest enhancement effect on luminol CL system after its aggregation. The CL enhancement mechanism was investigated, and the marked enhancement of aggregated 2.6 nm AuNPs for luminol CL system was supposed to originate from the decrease of AuNPs' surface negative charge density compared to its dispersed state. For the luminol-H2O2-2.6 nm AuNPs CL system in the presence of organic compounds containing groups of OH, NH2, or SH, more than one factor played the role in influencing the CL intensity. It was found that the enhanced effect of aggregated 2.6 nm AuNPs induced by such organic compounds was much more significant than the inhibition effect of reducing groups of OH, NH2, or SH, which made it applicable for the determination of this kind of compounds.

  14. Determination of ferric iron chelators by high-performance liquid chromatography using luminol chemiluminescence detection.

    PubMed

    Ariga, Tomoko; Imura, Yuki; Suzuki, Michio; Yoshimura, Etsuro

    2016-03-01

    Iron is an essential element for higher plants, and its acquisition and transportation is one of the greatest limiting factors for plant growth because of its low solubility in normal soil pHs. Higher plants biosynthesize ferric iron [Fe(III)] chelator (FIC), which solubilizes the iron and transports it to the rhizosphere. A high-performance liquid chromatography (HPLC) post-column method has been developed for the analysis of FICs using the luminol/H2O2 system for chemiluminescence (CL) detection. A size-exclusion column was the most suited in terms of column efficiency and CL detection efficiency. Mixing of the luminol with H2O2 in a post-column reaction was feasible, and a two-pump system was used to separately deliver the luminol and H2O2 solutions. The luminol and H2O2 concentrations were optimized using Fe(III)-EDTA and Fe(III)-citrate (Cit) solutions as analytes. A strong CL intensity was obtained for Fe(III)-Cit when EDTA was added to the luminol solution, probably because of an exchange of Cit with EDTA after separation on the HPLC column; CL efficiency was much higher for Fe(III)-EDTA than for Fe(III)-Cit with the luminol/H2O2 system. The present method can detect minute levels of Fe(III)-FICs; the detection limits of Fe(III)-EDTA, Fe(III)-Cit and Fe(III)-nicotianamine were 0.77, 2.3 and 1.1pmol, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Enhanced effect of aggregated gold nanoparticles on luminol chemiluminescence system and its analytical application.

    PubMed

    Qi, Yingying; Li, Baoxin

    2013-07-01

    Some organic compounds containing groups of OH, NH2, or SH, which could induce the aggregation of gold nanoparticles (AuNPs), were observed to enhance effectively the luminol-H2O2-2.6 nm AuNPs CL system. It was found that the aggregation of AuNPs was an important effect factor for the catalytic activity of AuNPs on luminol CL system. The aggregated AuNPs could effectively enhance luminol CL signal compared with the dispersed one. The enhanced effect was closely related to the sizes of AuNPs. Among the studied AuNPs with seven sizes, 2.6 nm AuNPs had the greatest enhancement effect on luminol CL system after its aggregation. The CL enhancement mechanism was investigated, and the marked enhancement of aggregated 2.6 nm AuNPs for luminol CL system was supposed to originate from the decrease of AuNPs' surface negative charge density compared to its dispersed state. For the luminol-H2O2-2.6 nm AuNPs CL system in the presence of organic compounds containing groups of OH, NH2, or SH, more than one factor played the role in influencing the CL intensity. It was found that the enhanced effect of aggregated 2.6 nm AuNPs induced by such organic compounds was much more significant than the inhibition effect of reducing groups of OH, NH2, or SH, which made it applicable for the determination of this kind of compounds. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Delayed luminescence of luminol initiated by a membrane-bound peroxidase.

    PubMed

    Ikariyama, Y; Suzuki, S; Aizawa, M

    1981-09-01

    The luminescense of the luminol-H2O2 system was initiated by either free or membrane-bound horseradish peroxideae (HRP). The instantaneous luminescene decayed rapidly and was followed by the delayed luminescence in the presence of excess luminol. The delayed luminescence was characterized by a chain reaction, in which luminescence intensity increased exponentially. Membrane-bound HRP demonstrated that the delayed luminescence took place even in the absence of HRP if the instantaneous luminescence was initiated by HRP. A mechanism for the nonenzymatic luminescence is proposed and discussed.

  17. The effect of culture media on the production and measurement of luminol-dependent chemiluminescence.

    PubMed Central

    Hastings, M. J.; Petricevic, I.; Williams, A. J.; Cole, P. J.; Easmon, C. S.

    1982-01-01

    The effect of various media constituents on the production and measurement of luminol-dependent chemiluminescence by neutrophils stimulated by opsonized zymosan was studied. Glucose, calcium ions and magnesium ions were found to be necessary for optimal chemiluminescence although high concentrations of glucose had a detrimental effect. For our luminol-dependent system, a pH of 8.5 give maximal readings. The use of simple balanced salt solutions gave higher chemiluminescence responses than did more complex media with added protein, amino acids, and vitamins. However, the latter were important in the maintenance of optimal cell function. PMID:7073957

  18. Electrochemiluminescence of luminol in alkaline solution at a paraffin-impregnated graphite electrode.

    PubMed

    Cui, Hua; Zou, Gui Zheng; Lin, Xiang-Qin

    2003-01-15

    The behavior of luminol electrochemiluminescence (ECL) at a paraffin-impregnated graphite electrode (PIGE) at different applied potentials was studied. Five ECL peaks were observed at 0.31, 0.59, 1.09, 1.54, and -0.58 V versus SCE, respectively, being related to potential scan direction and ranges, N2, O2, pH of the solution, and KCl concentration. The emission spectra of various ECL peaks at different potentials showed that all ECL peaks were initiated by luminol reactions. X-ray diffraction demonstrated that a simple mixture was formed between graphite and paraffin. The fluorescence spectra on the surface of the PIGE suggested that certain groups on the graphite were oxidized when the positive potential was applied to the electrode. In the presence of O2, three main ECL peaks were obtained in 0.1 mol/L KCl at pH 12.2. The ECL peak at 0.59 V with a shoulder is likely due to the reaction of luminol radicals with O2 and further electrooxidation of luminol radicals. The ECL peak at 1.54 V was suggested to be due to the electrooxidation of OH- to HO2- at higher potential and then to O2-, which reacted with luminol to produce light emission. Moreover, the oxygen-containing functional groups formed by the oxidation of the surface of the graphite electrode might enhance the ECL. At -0.58 V, the dissolved oxygen in solution was reduced to HO2-, resulting in light emission. At a potential higher than 1.64 V, ClO- was formed, leading to a broad emission wave and enhancement of the ECL peak at -0.58 V upon the reversal scan. Under nitrogen atmosphere, an ECL peak appeared at 1.09 V. At this potential, OH- was oxidized to O2, followed by the reaction with luminol to generate light emission. At pH 13.2 or 0.5 mol/L KCl, the shoulder of the ECL peak at 0.59 V became an ECL peak at 0.31 V. The conversion of luminol radicals into excited 3-aminophthalate may undergo two routes. Under these conditions, two routes might proceed at a different rate to form another ECL peak. It is

  19. Attenuation of gouty arthritis by emodinol in monosodium urate crystal-treated mice.

    PubMed

    Chen, Lvyi; Lan, Zhou; Ma, Shuwei; Zhao, Ling; Yang, Xinzhou

    2013-05-01

    A series of studies have recently demonstrated that the release of interleukin 1β induced by monosodium urate crystals is central to the experimental gouty arthritis. Elaeagnus pungens has been traditionally used for the treatment of gouty arthritis in China for more than thousands years. However, there is still little known about the active ingredients and mechanisms of E. pungens against gouty arthritis. Emodinol, as a major triterpene compound in E. pungens, has been seldom reported to have an effect on gouty arthritis. Therefore, the potential beneficial effects and mechanisms of emodinol on gouty arthritis were investigated in this study. Results showed that it significantly ameliorated the hyperalgesia, inflammation, and levels of multiple proinflammatory cytokines in monosodium urate crystals-treated mice. These findings elucidate that emodinol exhibits a prominent effect on improving symptoms of acute gouty arthritis induced by monosodium urate crystals through inhibiting the generation of proinflammatory cytokines.

  20. Flavor preferences conditioned by oral monosodium glutamate in mice.

    PubMed

    Ackroff, Karen; Sclafani, Anthony

    2013-11-01

    The prototypic umami substance monosodium glutamate (MSG) reinforces preferences for its own flavor, as well as preferences for flavors associated with it, by conditioning processes. Mice of 3 inbred strains (C57BL/6J (B6), 129P3/J, and FVB/NJ) and 2 taste-knockout (KO) groups derived from the B6 lineage were initially indifferent to 200mM MSG, but this evaluation was altered by forced exposure to MSG. B6 and KO mice acquired an MSG preference, 129 mice remained indifferent, and FVB mice avoided MSG. The shifts in preference imply a postoral basis for MSG effects, suggesting that it could produce preferences for associated flavors. New mice were trained with a conditioned stimulus (CS+) flavor mixed in 200mM MSG and a CS- flavor in water. Similar to the parent B6 strain, mice missing the T1r3 element of an umami receptor or the downstream signaling component Trpm5 learned to prefer the CS+ flavor and subsequently showed similar preferences for MSG in an ascending concentration series. Consistent with their responses to forced exposure, the 129 strain did not acquire a significant CS+ preference, and the FVB strain avoided the CS+ flavor. The 129 and FVB strains showed little attraction in the ascending MSG concentration series. Together, these data indicate that the postoral effects of MSG can modulate responses to its own and MSG-paired flavors. The basis for strain differences in the responses to MSG is not certain, but the taste-signaling elements T1r3 and Trpm5, which are also present in the gut, are not required for mediation of this flavor learning.

  1. Monosodium urate crystals induce oxidative stress in human synoviocytes.

    PubMed

    Zamudio-Cuevas, Yessica; Martínez-Flores, Karina; Fernández-Torres, Javier; Loissell-Baltazar, Yahir A; Medina-Luna, Daniel; López-Macay, Ambar; Camacho-Galindo, Javier; Hernández-Díaz, Cristina; Santamaría-Olmedo, Mónica G; López-Villegas, Edgar Oliver; Oliviero, Francesca; Scanu, Anna; Cerna-Cortés, Jorge Francisco; Gutierrez, Marwin; Pineda, Carlos; López-Reyes, Alberto

    2016-05-21

    Gout is the most common inflammatory arthropathy of metabolic origin and it is characterized by intense inflammation, the underlying mechanisms of which are unknown. The aim of this study was to evaluate the oxidative stress in human fibroblast-like synoviocytes (FLS) exposed to monosodium urate (MSU) crystals, which trigger an inflammatory process. Human FLS isolated from synovial tissue explants were stimulated with MSU crystals (75 μg/mL) for 24 h. Cellular viability was evaluated by crystal violet staining, apoptosis was assessed using Annexin V, and the cellular content of reactive oxygen species (ROS) and nitrogen species (RNS) (O2 (-), H2O2, NO) was assessed with image-based cytometry and fluorometric methods. In order to determine protein oxidation levels, protein carbonyls were detected through oxyblot analysis, and cell ultrastructural changes were assessed by transmission electron microscopy. The viability of FLS exposed to MSU crystals decreased by 30 % (P < 0.05), while apoptosis increased by 42 % (P = 0.01). FLS stimulated with MSU crystals exhibited a 2.1-fold increase in H2O2 content and a 1.5-fold increase in O2 (-) and NO levels. Oxyblots revealed that the spots obtained from FLS protein lysates exposed to MSU crystals exhibited protein carbonyl immunoreactivity, which reflects the presence of oxidatively modified proteins. Concomitantly, MSU crystals triggered the induction of changes in the morphostructure of FLS, such as the thickening and discontinuity of the endoplasmic reticulum, and the formation of vacuoles and misfolded glycoproteins. Our results prove that MSU crystals induce the release of ROS and RNS in FLS, subsequently oxidizing proteins and altering the cellular oxidative state of the endoplasmic reticulum, which results in FLS apoptosis.

  2. Update on food safety of monosodium l-glutamate (MSG).

    PubMed

    Henry-Unaeze, Helen Nonye

    2017-09-18

    This evidence-based safety review of the flavor enhancer monosodium l-glutamate (MSG) was triggered by its global use and recent studies expressing some safety concerns. This article obtained information through search of evidence-based scientific databases, especially the US National Library of Medicine NIH. (A) MSG is a water-soluble salt of glutamate, a non-essential amino acid, normally synthesized in the body and prevalent in protein foods. (B) MSG is utilized world-wide for its "umami" taste and flavor enhancement qualities, (C) the human body does not discriminate between glutamate present in food and that added as seasoning, (D) glutamate metabolism is compartmentalized in the human body without reported ethnic differences, (E) glutamate does not passively cross biological membranes, (F) food glutamate is completely metabolized by gut cells as energy source and serves as key substrate for other important metabolites in the liver, (G) normal food use of MSG is dose-dependent and self-limiting without elevation in plasma glutamate, (H) the recent EFSA acceptable daily intake (30mg/kg body weight/day) is not attainable when MSG is consumed at normal dietary level, (I) scientists have not been able to consistently elicit reactions in double-blind studies with 'sensitive' individuals using MSG or placebo in food. Based on the above observations (A-I), high quality MSG is safe for all life-cycle stages without respect to ethnic origin or culinary background. MSG researchers are advised to employ appropriate scientific methodologies, consider glutamate metabolism and its normal food use before extrapolating pharmacological rodent studies to humans. Copyright © 2017. Published by Elsevier B.V.

  3. Novel Iron(III)-Based Metal-Organic Gels with Superior Catalytic Performance toward Luminol Chemiluminescence.

    PubMed

    He, Li; Peng, Zhe Wei; Jiang, Zhong Wei; Tang, Xue Qian; Huang, Cheng Zhi; Li, Yuan Fang

    2017-09-20

    Novel metal-organic gels (MOGs) consisting of iron (Fe(3+)) as the central ion and 1,10-phenanthroline-2,9-dicarboxylic acid (PDA) as the ligand were synthesized by a mild facile strategy. The Fe(III)-containing metal-organic xerogels (Fe-MOXs), obtained after removing the solvents in MOGs, were found to exhibit outstanding performance in the catalysis of luminol chemiluminescence (CL) for the first time even in the absence of extra oxidants such as hydrogen peroxide. The possible CL mechanism was discussed according to the electro/optical measurements, including electron paramagnetic resonance (EPR), UV-vis absorption, and CL spectra, as well as the effects of radical scavengers on Fe-MOXs-catalyzed luminol CL system, suggesting that the CL emission of luminol might originate from the intrinsic oxidase-like catalytic activity of Fe-MOXs on the decomposition of dissolved oxygen. Additionally, the potential practical application of the resulting luminol-Fe-MOXs system was evaluated by the quantitative analysis of dopamine. Good linearity over the range from 0.05 to 0.6 μM was obtained with the limit of detection (LOD, 3σ) of 20.4 nM and acceptable recoveries ranging from 98.6 to 105.4% in human urine. These results may open up the promising application of novel metal-organic gels as highly effective catalysts in the field of chemiluminescence.

  4. Effect of some psychotropic drugs on the activated macrophage-induced luminol-dependent chemiluminescence.

    PubMed

    Hadjimitova, V; Traykov, T; Goliysky, P; Ribarov, S

    1999-04-01

    The effect of some psychotropic drugs on the activity of macrophages to produce superoxide radicals during phagocytosis was tested. Three-cyclic antidepressants, imipramine and amitriptyline, and the thioxanthene neuroleptic, chlorprothixene, were studied. The superoxide production was measured by luminol-dependent chemiluminescence. The drugs were investigated in the concentration range of 10(-7)-10(-4) mol/l. It was seen that all tested drugs caused a concentration-dependent decrease of the luminol-dependent chemiluminescence. The inhibitory effect of imipramine and amitriptyline on the macrophage superoxide production was moderate, while the effect of chlorprothixene was significantly stronger (a decrease more than 100 times that of macrophage chemiluminescence). Essentially, the luminol-dependent chemiluminescence reflects the level of superoxide radicals in the system. Therefore, the effect of drugs may be due to the possible activity for scavenging superoxide. In additional experiments with different systems of generations of O2- and different methods of registration, this possibility was discarded. Therefore, the effect of the drugs on the luminol-dependent chemiluminescence seems to be due to drug-induced decrease of the ability of activated macrophages to produce superoxide radicals.

  5. Dynamically tunable chemiluminescence of luminol-functionalized silver nanoparticles and its application to protein sensing arrays.

    PubMed

    He, Yi; He, Xiao; Liu, Xiaoying; Gao, Lingfeng; Cui, Hua

    2014-12-16

    It is still a great challenge to develop an array-based sensing system that can obtain only multiparameters, according to a single experiment and device. The role of conventional chemiluminescence (CL) in biosensing has been limited to a signal transducer in which a single signal (CL intensity) can be obtained for quantifying the concentrations of analytes. In this work, we have developed an dynamically tunable CL system, based on the reaction of luminol-functionalized silver nanoparticles (luminol-AgNPs) with H2O2, which could be tunable via adjusting various conditions such as the concentration of H2O2, pH value, and addition of protein. A single experiment operation could obtain multiparameters including CL intensity, the time to appear CL emission and the time to reach CL peak value. The tunable, low-background, and highly reproducible CL system based on luminol-AgNPs is applied, for the first time, as a sensing platform with trichannel properties for protein sensing arrays by principal component analysis. Identification of 35 unknowns demonstrated a success rate of >96%. The developed sensing arrays based on the luminol-AgNPs provide a new way to use nanoparticles-based CL for the fabrication of sensing arrays and hold great promise for biomedical application in the future.

  6. Luminol-based chemiluminescent signals: clinical and non-clinical application and future uses.

    PubMed

    Khan, Parvez; Idrees, Danish; Moxley, Michael A; Corbett, John A; Ahmad, Faizan; von Figura, Guido; Sly, William S; Waheed, Abdul; Hassan, Md Imtaiyaz

    2014-05-01

    Chemiluminescence (CL) is an important method for quantification and analysis of various macromolecules. A wide range of CL agents such as luminol, hydrogen peroxide, fluorescein, dioxetanes and derivatives of oxalate, and acridinium dyes are used according to their biological specificity and utility. This review describes the application of luminol chemiluminescence (LCL) in forensic, biomedical, and clinical sciences. LCL is a very useful detection method due to its selectivity, simplicity, low cost, and high sensitivity. LCL has a dynamic range of applications, including quantification and detection of macro and micromolecules such as proteins, carbohydrates, DNA, and RNA. Luminol-based methods are used in environmental monitoring as biosensors, in the pharmaceutical industry for cellular localization and as biological tracers, and in reporter gene-based assays and several other immunoassays. Here, we also provide information about different compounds that may enhance or inhibit the LCL along with the effect of pH and concentration on LCL. This review covers most of the significant information related to the applications of luminol in different fields.

  7. Synthesis and characterizations of iso-luminol-functionalized, tadpole-shaped, gold nanomaterials.

    PubMed

    Li, Fang; Tian, Dayong; Cui, Hua

    2013-01-01

    Iso-luminol functionalized gold nanomaterials were synthesized in high yield by a simple seeding approach, using the chemiluminescent reagent iso-luminol as reductant in the presence of HAuCl(4), AgNO(3) and cetyltrimethylammonium bromide (CTAB). The morphology of as-prepared gold nanoparticles was characterized by transmission electron microscopy and UV-vis spectroscopy, showing that gold nanotadpoles (AuNTps) were obtained. Subsequent experiments revealed that the amounts of seed colloids and AgNO(3) and the concentrations of iso-luminol and CTAB in the growth solution play critical roles in the formation of well-shaped AuNTps. The surface state of AuNTps was characterized by UV-vis spectroscopy and fluorescence spectroscopy, indicating that iso-luminol and its oxidation product, 4-aminophthalate, coexisted on the surface of AuNTps. The CL behaviour was studied by static injection CL experiments, demonstrating that AuNTps were of CL activity. Finally, the growth mechanism of AuNTps was also discussed. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Amino acids as novel nucleophiles for silver nanoparticle-luminol chemiluminescence.

    PubMed

    Li, Na; Ni, Shubiao

    2014-12-01

    The use of noble metal nanoparticles (NPs) as reductants in chemiluminescence (CL) has been reported only rarely owing to their high oxidation potentials. Interestingly, nucleophiles could dramatically lower the oxidation potential of Ag NPs, such that in the presence of nucleophiles Ag NPS could be used as reductants to induce the CL emission of luminol, an important CL reagent widely used in forensic analysis for the detection of trace amounts of blood. Although nucleophiles are indispensible in Ag NP-luminol CL, only inorganic nucleophiles such as Cl(-), Br(-), I(-) and S2O3 (2-) have been shown to be efficient. The effects of organic nucleophiles on CL remain unexplored. In this study, 20 standard amino acids were evaluated as novel organic nucleophiles in Ag NP-luminol CL. Histidine, lysine and arginine could initiate CL emission; the others could not. It is proposed that the different behaviors of 20 standard amino acids in the CL reactions derive from the interface chemistry between Ag NPs and these amino acids. UV/vis absorption spectra were studied to validate the interface chemistry. In addition, imidazole and histidine were chosen as a model pair to compare the behavior of the monodentate nucleophile with that of the corresponding multidentate nucleophile in Ag NP-luminol CL. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Albumin inhibits human polymorphonuclear leucocyte luminol-dependent chemiluminescence: evidence for oxygen radical scavenging.

    PubMed Central

    Holt, M. E.; Ryall, M. E.; Campbell, A. K.

    1984-01-01

    Luminol-dependent chemiluminescence of normal human polymorphonuclear leucocytes (PMN) which were resting, or stimulated by unopsonized latex beads, opsonized zymosan or the chemotactic peptide N-formyl-met-leu-phe was decreased more than 80% in the presence of physiological concentrations of albumin (4%, w/v). This inhibition did not result from impairment of light transmission, cellular toxicity, luminol excited-state quenching or a dialysable contaminant in the albumin preparation, but was reduced by 30% when the fall induced by albumin in extracellular free Ca2+ concentration was corrected. The inhibition was most apparent in the larger second phase of the PMN chemiluminescent response to chemotactic peptide or opsonized zymosan stimulation. The smaller first phase of these responses was in fact enhanced by low concentrations of albumin (0.05-0.5%, w/v) and only inhibited up to 50% by 4% (w/v) albumin. Albumin in the range 0.1-4% (w/v) exerted a similar effect on chemiluminescence resulting from superoxide anion (O-2) and hydrogen peroxide (H2O2) production by xanthine oxidase catalysed oxidation of xanthine in the presence of luminol. We suggest that the effect of albumin on PMN luminol-dependent chemiluminescence is mediated by modification of the oxygen radical generating pathway, or oxygen radical scavenging. This previously undocumented property of the major extracellular protein requires further examination if oxygen radicals are to be established as important mediators of inflammation. PMID:6712882

  10. [Effect of "Fit" dishwashing detergent from former Eastern Germany (GDR) on luminol luminescence].

    PubMed

    Heuser, Katrin; Oehmen, Martin; Nadine, Kühner; Benecke, Mark

    2006-01-01

    The forensic luminol test is used to screen large areas for the presence of blood. The heme-induced reduction of hydrogen peroxide is coupled to the oxidation of luminol resulting in luminescence. However, photographic documentation of the relatively weak and short-lived luminescence is difficult and luminol is now often replaced by other chemicals. In this study, we investigated reports from the Rostock police department that the addition of "Fit", a dishwashing detergent from former Eastern Germany, could both intensify and prolong the luminescence of luminol on blood stains. Even though this effect was reported only for the original composition of Fit but not the currently sold version, we found that both the old and the new version of Fit increase the brightness of the luminescence while decreasing its duration. This may be due to detergents in the dishwashing liquid, which permeabilize the plasma membrane of the erythrocytes, exposing the Fe3+ inside the cell and speeding up the entire reaction. We did not find any evidence of special ingredients in the old version of Fit that would cause both the increased brightness and prolonged duration of luminescence as reported by the Rostock PD.

  11. Luminol-Based Chemiluminescent Signals: Clinical and Non-clinical Application and Future Uses

    PubMed Central

    Khan, Parvez; Idrees, Danish; Moxley, Michael A.; Corbett, John A.; Ahmad, Faizan; von Figura, Guido; Sly, William S.; Waheed, Abdul

    2015-01-01

    Chemiluminescence (CL) is an important method for quantification and analysis of various macromolecules. A wide range of CL agents such as luminol, hydrogen peroxide, fluorescein, dioxetanes and derivatives of oxalate, and acridinium dyes are used according to their biological specificity and utility. This review describes the application of luminol chemiluminescence (LCL) in forensic, biomedical, and clinical sciences. LCL is a very useful detection method due to its selectivity, simplicity, low cost, and high sensitivity. LCL has a dynamic range of applications, including quantification and detection of macro and micromolecules such as proteins, carbohydrates, DNA, and RNA. Luminol-based methods are used in environmental monitoring as biosensors, in the pharmaceutical industry for cellular localization and as biological tracers, and in reporter gene-based assays and several other immunoassays. Here, we also provide information about different compounds that may enhance or inhibit the LCL along with the effect of pH and concentration on LCL. This review covers most of the significant information related to the applications of luminol in different fields. PMID:24752935

  12. Bleach interference in forensic luminol tests on porous surfaces: more about the drying time effect.

    PubMed

    Castelló, Ana; Francés, Francesc; Verdú, Fernando

    2009-02-15

    As criminals try to avoid leaving clues at the scene of a crime, bloodstains are often washed away, but fortunately for investigators, they are difficult to eliminate completely. Porous surfaces easily retain blood traces, which are sometimes invisible to the naked eye. The reagent of choice for detecting latent blood traces on all types of surfaces is luminol, but its main disadvantage is a high degree of sensitivity to oxidising contaminants in the blood sample. If household bleach is used to clean bloodstains, presumptive tests are invalidated. Hypochlorites, however, are known to be unstable and deteriorate over time, and this feature could be of help in preventing household bleach-induced interference. Previous studies have evaluated the effect of the drying time on nonporous surfaces, but nothing has as yet been published about this effect on porous surfaces. Consequently, this paper reports on hypochlorite interference with luminol reagents used on this type of surface, evaluating the effects of drying time on the household bleach-luminol reaction, and ascertaining whether the drying procedure could be applied to prevent household bleach interference on bloodstained porous surfaces. The results indicate that the drying method may very well overcome household bleach interference in luminol reaction tests, if the investigation allows for an appropriate waiting time.

  13. Effect of amino compounds on luminol-H2O2-gold nanoparticle chemiluminescence system.

    PubMed

    Liu, Wei; Luo, Jing; Zhao, Mei; Li, Huifang; Li, Baoxin

    2016-12-01

    In this work, the effect of amino compounds on the catalytic property of gold nanoparticles (AuNPs) in the luminol-H2O2 chemiluminescence (CL) system was systematically investigated. The experimental results showed that the catalytic ability of AuNPs on luminol-H2O2 system can be changed after AuNPs interacted with the amino compounds. It was found that two main aspects influence the catalytic property of AuNPs: (1) the electron density in conduction bands of AuNPs and (2) the surface negative charge density of AuNPs. Some amino compounds can decrease the electron density in the conduction bands of AuNPs after they reacted with AuNPs, resulting in a decrease of the catalytic property of AuNPs on luminol-H2O2 system. However, some amino compounds can cause AuNPs to aggregate after they reacted with AuNPs. The surface negative charge density of AuNPs would decrease, and zeta potentials were tested to verify the change of the surface negative charge density of AuNPs. As a result, the catalytic property of AuNPs on luminol-H2O2 system increased, and an enhanced CL signal can be obtained after the amino compounds reacted with AuNPs. This work will help people understand the catalytic mechanism of AuNPs and establish the CL method for the determination of amino compounds. Graphical Abstract Effects of amino compound on luminol-H2O2-AuNPs CL system.

  14. Blood transfusions impair anastomotic wound healing, reduce luminol-dependent chemiluminescence, and increase interleukin-8.

    PubMed

    Okano, T; Ohwada, S; Sato, Y; Sato, N; Toyama, Y; Nakasone, Y; Ogawa, T; Morishita, Y

    2001-01-01

    Several studies have shown that perioperative blood transfusion increases the risk of infectious complications after surgery or trauma, however, the mechanisms behind the susceptibility to infection and impaired wound healing are not clear. This study was designed to investigate the effects of blood transfusion on anastomotic wound healing, luminol-dependent chemiluminescence, and interleukin-8. Male Wistar rats were divided into seven groups: groups C and Tx underwent laparotomy and the other groups underwent gastrectomy and gastroduodenostomy. Groups C and G received saline; groups Tx and GT received whole blood; and groups GPT, GAT, and GRT received plasma, autologous blood, and irradiated, leukocyte-depleted whole blood, respectively. The breaking strength of the anastomosis, and plasma factor XIII, interleukin-8, and luminol-dependent chemiluminescence levels were measured. The plasma XIII level in group GT was significantly (P < 0.05) lower that in groups G, GPT, GAT, and GRT. The maximum breaking strength was significantly reduced in groups GT, GRT, GPT, and GAT compared to the other groups, and there was no significance between different types of transfusion. Luminol-dependent chemiluminescence levels in groups GT were severely reduced, while the and luminol-dependent chemiluminescence levels in groups GRT, GPT, and GAT were almost the same as the levels in group G. The plasma interleukin-8 levels were higher in the transfused groups, and lower in groups GRT, GPT, and GAT. Blood transfusions increased the incidence of anastomotic abscess and impaired anastomotic wound healing. These might be related to the reduced luminol-dependent chemiluminescence and increased interleukin-8. Autologous blood, plasma, and irradiated, leukocyte-depleted packed cells can abrogate these effects.

  15. Growth and adhesion properties of monosodium urate monohydrate (MSU) crystals

    NASA Astrophysics Data System (ADS)

    Perrin, Clare M.

    The presence of monosodium urate monohydrate (MSU) crystals in the synovial fluid has long been associated with the joint disease gout. To elucidate the molecular level growth mechanism and adhesive properties of MSU crystals, atomic force microscopy (AFM), scanning electron microscopy, and dynamic light scattering (DLS) techniques were employed in the characterization of the (010) and (1-10) faces of MSU, as well as physiologically relevant solutions supersaturated with urate. Topographical AFM imaging of both MSU (010) and (1-10) revealed the presence of crystalline layers of urate arranged into v-shaped features of varying height. Growth rates were measured for both monolayers (elementary steps) and multiple layers (macrosteps) on both crystal faces under a wide range of urate supersaturation in physiologically relevant solutions. Step velocities for monolayers and multiple layers displayed a second order polynomial dependence on urate supersaturation on MSU (010) and (1-10), with step velocities on (1-10) generally half of those measured on MSU (010) in corresponding growth conditions. Perpendicular step velocities on MSU (010) were obtained and also showed a second order polynomial dependence of step velocity with respect to urate supersaturation, which implies a 2D-island nucleation growth mechanism for MSU (010). Extensive topographical imaging of MSU (010) showed island adsorption from urate growth solutions under all urate solution concentrations investigated, lending further support for the determined growth mechanism. Island sizes derived from DLS experiments on growth solutions were in agreement with those measured on MSU (010) topographical images. Chemical force microscopy (CFM) was utilized to characterize the adhesive properties of MSU (010) and (1-10). AFM probes functionalized with amino acid derivatives and bio-macromolecules found in the synovial fluid were brought into contact with both crystal faces and adhesion forces were tabulated into

  16. The Monosodium Glutamate Story: The Commercial Production of MSG and Other Amino Acids

    ERIC Educational Resources Information Center

    Ault, Addison

    2004-01-01

    Monosodium glutamate (MSG) is both the basis of a trillion dollar worldwide industry and a presence in the diet of a majority of the inhabitants of the world. Some parts of the "story" of MSG that might be of most interest to chemists, chemistry teachers and their students are presented.

  17. The Monosodium Glutamate Story: The Commercial Production of MSG and Other Amino Acids

    ERIC Educational Resources Information Center

    Ault, Addison

    2004-01-01

    Monosodium glutamate (MSG) is both the basis of a trillion dollar worldwide industry and a presence in the diet of a majority of the inhabitants of the world. Some parts of the "story" of MSG that might be of most interest to chemists, chemistry teachers and their students are presented.

  18. Final Report on Phase III Testing of Monosodium Titanate Adsorption Kinetics

    SciTech Connect

    Hobbs, D.T.

    1999-09-29

    This study consisted of a statistically designed set of tests to determine the extent and rate of adsorption of strontium, plutonium, uranium, and neptunium as a function of temperature, monosodium titanate (MST) concentration, and concentrations of sodium, strontium, plutonium, uranium, and neptunium.

  19. Monosodium glutamate-induced damage in liver and kidney: a morphological and biochemical approach.

    PubMed

    Ortiz, G G; Bitzer-Quintero, O K; Zárate, C Beas; Rodríguez-Reynoso, S; Larios-Arceo, F; Velázquez-Brizuela, I E; Pacheco-Moisés, F; Rosales-Corral, S A

    2006-02-01

    It has been demonstrated that high concentrations of monosodium glutamate in the central nervous system induce neuronal necrosis and damage in retina and circumventricular organs. In this model, the monosodium glutamate is used to induce an epileptic state; one that requires highly concentrated doses. The purpose of this study was to evaluate the toxic effects of the monosodium glutamate in liver and kidney after an intra-peritoneal injection. For the experiment, we used 192 Wistar rats to carry out the following assessments: a) the quantification of the enzymes alanine aminotransferase and aspartate aminotransferase, b) the quantification of the lipid peroxidation products and c) the morphological evaluation of the liver and kidney. During the experiment, all of these assessments were carried out at 0, 15, 30 and 45 min after the intra-peritoneal injection. In the rats that received monosodium glutamate, we observed increments in the concentration of alanine aminotransferase and aspartate aminotransferase at 30 and 45 min. Also, an increment of the lipid peroxidation products, in kidney, was exhibited at 15, 30 and 45 min while in liver it was observed at 30 and 45 min. Degenerative changes were observed (edema-degeneration-necrosis) at 15, 30 and 45 min.

  20. Effect of L (+) ascorbic acid and monosodium glutamate concentration on the morphology of calcium carbonate

    NASA Astrophysics Data System (ADS)

    Saraya, Mohamed El-shahte Ismaiel

    2015-11-01

    In this study, monosodium glutamate and ascorbic acid were used as crystal and growth modifiers to control the crystallization of CaCO3. Calcium carbonate prepared by reacting a mixed solution of Na2CO3 with CaCl2 at ambient temperature, (25 °C), constant Ca++/ CO3- - molar ratio and pH with stirring. The polymorph and morphology of the crystals were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results indicate that rhombohedral calcite was only formed in water without organic additives, and both calcite and spherical vaterite with various morphologies were produced in the presence of monosodium glutamate. The content of vaterite increased as the monosodium glutamate increased. In addition, spherical vaterite was obtained in the presence of different concentrations of ascorbic acid. The spherical vaterite posses an aggregate shape composed of nano-particles, ranging from 30 to 50 nm as demonstrated by the SEM and TEM analyses. Therefore, the ascorbic stabilizes vaterite and result in nano-particles compared to monosodium glutamate.

  1. Supplementing monosodium glutamate to partial enteral nutrition slows gastric emptying in preterm pigs

    USDA-ARS?s Scientific Manuscript database

    Emerging evidence suggests that free glutamate may play a functional role in modulating gastroduodenal motor function. We hypothesized that supplementing monosodium glutamate (MSG) to partial enteral nutrition stimulates gastric emptying in preterm pigs. Ten-day-old preterm, parenterally fed pigs re...

  2. Inhibition of superoxide dismutase, Vitamin C and glutathione on chemiluminescence produced by luminol and the mixture of sulfite and bisulfite

    NASA Astrophysics Data System (ADS)

    Geng, Hong; Meng, Ziqiang

    2006-05-01

    In a system which consisted of luminol (3-aminophthalhydrazide), cobalt sulfate (CoSO 4), alkaline buffer and the mixture of NaSO 3 and sodium bisulfite (NaHSO 3) (sulfite and bisulfite = 3:1, m/m), a strong chemiluminescence (CL) was observed using a BPCL ultra-weak luminometer. The CL signals resulted from 3-aminophthalate (the product of oxidized luminol), and were affected by the buffer pH, buffer medium and the concentrations of luminol, CoSO 4 and the NaSO 3-NaHSO 3 mixture. The observation that the CL intensities were inhibited by superoxide dismutase (SOD), Vitamin C (Vc) and glutathione (GSH) in a dose-dependent manner suggested that superoxide radical (O 2rad -) was involved in the CL reaction and responsible for oxidation of luminol.

  3. Dual-channel cathodic electrochemiluminescence of luminol induced by injection of hot electrons on a niobate semiconductor modified electrode.

    PubMed

    Xu, Huifeng; Ye, Hongzhi; Zhu, Xi; Liang, Shijing; Guo, Longhua; Lin, Zhenyu; Liu, Xianxiang; Chen, Guonan

    2013-01-07

    In this paper, a new niobate semiconductor photocatalyst Sr(0.4)H(1.2)Nb(2)O(6)·H(2)O (HSN) nanoparticle was applied to investigate the cathodic electrochemiluminescent (ECL) behavior of luminol for the first time. The results presented here demonstrated that there were two ECL peaks of luminol at the cathodic potential attributed to immobilization of HSN on the electrode surface. It is implied that HSN can be electrically excited and injected electrons into aqueous electrolytes from this electrode under a quite low potential that only excites luminol. A mechanism for this luminol-ECL system on HSN/GCE has been proposed. Additionally, this HSN/GCE has lots of advantages, such as high stability, good anti-interference ability, simple instrumentation, rapid procedure and ultrasensitive ECL response. It is envisioned that this HSN/GCE has further applications in biosensors.

  4. Direct electrochemiluminescence of gold nanoparticles bifunctionalized by luminol analogue-metal complexes in neutral and alkaline media.

    PubMed

    Shu, Jiangnan; Wang, Wei; Cui, Hua

    2015-07-21

    Electrochemiluminescence of gold nanoparticles bifunctionalized by luminol analogue-metal complexes was studied for the first time. Strong direct electrochemiluminescence was observed in neutral and alkaline media without an additional coreactant.

  5. Visual electrochemiluminescence detection of telomerase activity based on multifunctional Au nanoparticles modified with G-quadruplex deoxyribozyme and luminol.

    PubMed

    Zhang, Huai-Rong; Wang, Yin-Zhu; Wu, Mei-Sheng; Feng, Qiu-Mei; Shi, Hai-Wei; Chen, Hong-Yuan; Xu, Jing-Juan

    2014-10-25

    A novel visual electrochemiluminescence (ECL) analysis strategy for detection of telomerase activity is reported on a microarray chip, with G-quadruplex deoxyribozyme (DNAzyme) and luminol modified Au nanoparticles (NPs) as double-catalytic amplification labels.

  6. Application of 4-iodophenol-enhanced luminol chemiluminescence to direct detection of horseradish peroxidase encapsulated in liposomes.

    PubMed

    Kamidate, Tamio; Maruya, Masumi; Tani, Hirofumi; Ishida, Akihiko

    2009-09-01

    4-Iodophenol was applied to an enhancer in the direct detection of horseradish peroxidase (HRP) encapsulated in liposomes by using luminol chemiluminescence (CL). Luminol, 4-iodophenol and hydrogen peroxide permeate into the inner phase of liposomes containing HRP, resulting in the progress of 4-iodophenol-enhanced luminol CL catalyzed by HRP in liposomes. The CL intensity observed in liposomes was a factor of 150 greater than that observed in a lipid-free bulk solution. The detection limit in the direct detection of HRP encapsulated in liposomes was sensitive by a factor of 30 compared with that in a lipid-free bulk solution. 4-Iodophenol effectively functioned as an enhancer in HRP-catalyzed luminol CL in liposomes.

  7. A quantitative method for determining a representative detection limit of the forensic luminol test for latent bloodstains.

    PubMed

    Cassidy, Brianna M; Lu, Zhenyu; Martin, Jennifer P; Tazik, Shawna K; Kellogg, Katie W; DeJong, Stephanie A; Belliveau, Elle O; Kilgore, Katherine E; Ervin, Samantha M; Meece-Rayle, Mackenzie; Abraham, Alyssa M; Myrick, Michael L; Morgan, Stephen L

    2017-09-01

    The luminol test has been used for over 60 years by forensic investigators for presumptive identification of blood and visualization of blood splatter patterns. Multiple studies have estimated the limit of detection (LD) for bloodstains when luminol is employed, with results ranging from 100× to 5,000,000× dilute. However, these studies typically have not identified and controlled important experimental variables which may affect the luminol LD for bloodstains. Without control of experimental parameters in the laboratory, variables which affect the potential of presumptive bloodstain test methods remain largely unknown, and comparisons required to establish new, more powerful detection methods are simply impossible. We have developed a quantitative method to determine the relationship between the amount of blood present and its reaction with luminol by measuring, under controlled conditions, the resulting chemiluminescent intensity with a video camera, combined with processing of the digital intensity data. The method resulted in an estimated LD for bloodstains on cotton fabric at ∼200,000× diluted blood with a specific luminol formulation. Although luminol is the focus of this study, the experimental protocol used could be modified to study effects of variables using other blood detection reagents. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Coenzyme Q1-catalyzed luminol chemiluminescent assay for rapid antimicrobial susceptibility testing of Mycobacterium bovis.

    PubMed

    Yamashoji, Shiro

    2003-01-01

    Coenzyme Q1 is herein proposed as the best catalyst among coenzymes Q and vitamins K for quinone-catalyzed luminol chemiluminescent assays applied to rapid determination of viability or rapid antimicrobial susceptibility tests of Mycobacterium bovis. Luminol chemiluminescence intensity (LCI) was determined 10 min after the incubation of M. bovis with coenzyme Q1, and was proportional to CFU (colony-forming unit)/ml in the range of 9,000 to 2,250,000. LCI depended on the the production of the superoxide anion (O2-) rather than H2O2 during a 10-min incubation of M. bovis with coenzyme Q1, as superoxide dismutase reduced LCI more effectively than catalase. The minimal inhibitory concentrations (MICs) of 10 kinds of antituberculous agents estimated on the basis of decrease in LCI after one or two days' cultivation were in good agreement with MICs determined by turbidity analysis, which requires upwards of 1 week to complete.

  9. [Chemiluminescence in a stimulated polymorphonuclear leukocytes--luminol system: suppression by thiols].

    PubMed

    Murina, M A; Roshchupkin, D I; Belakina, N S; Filippov, S V

    2005-01-01

    The effect of some scavengers of thiol nature, which eliminate all reactive oxygen species and oxidants with reactive chlorine, on the luminol-enhanced chemiluminescence of polymorphonuclear leukocytes was studied. The use of two scavengers of this type (penetrating and not penetrating into the cell) made it possible to separate the luminescence of cell structures from the luminescence generated by oxidants in the surrounding medium. It was found that about a half of luminol luminescence is due to its oxidation in the medium surrounding the cell, and it is completely inhibited by the nonpenetrating reduced glutathione. The cell itself is a source of a considerable portion of luminescence, and this luminescence is quenched by penetrating sulfhydryl compounds such as dithiothreitol and N-acethyl cysteine. Reduced glutathione, which penetrates into cells and whose action is due only to the sulfhydryl group, is recommended as a candidate for the selective neutralization of extracellular oxidants.

  10. Effect of aggregated silver nanoparticles on luminol chemiluminescence system and its analytical application

    NASA Astrophysics Data System (ADS)

    Qi, Yingying; Li, Baoxin; Xiu, Furong

    2014-07-01

    We found that after silver nanoparticles (AgNPs) aggregated, its catalytic activity on luminol CL reaction obviously changed, and the change characteristic was closely related to the sizes of AgNPs. UV-visible spectra, X-ray photoelectron spectra, zeta potential and transmission electron microscopy studies were carried out to investigate the CL effect mechanism. The different CL responses of aggregated AgNPs with different size were suggested to be due to the two effects of quantum size and electron density in nanoparticle's conduction bands, and which one played a major role. The poisonous organic contaminants such as anilines, could induce the aggregation of AgNPs, were observed to affect effectively the luminol-H2O2-7 nm and 15 nm AgNPs CL systems and were detectable by use of a flow injection method with the enhanced or inhibited CL detection.

  11. The measurement of opsonic and phagocytic function by Luminol-dependent chemiluminescence.

    PubMed Central

    Easmon, C S; Cole, P J; Williams, A J; Hastings, M

    1980-01-01

    Luminol-dependent chemiluminescence produced by peripheral blood phagocytic cells was measured using a light detecting instrument, the Luminometer 1250 (LKB Wallac). Although less sensitive than liquid scintillation counters, the Luminometer can measure chemiluminescence effectively and detect experimentally induced and clinical variations using small numbers of cells. It is small, inexpensive, simple to use and allows temperature within the reaction vial to be controlled accurately. Light emission can be recorded either graphically or by an intergrated digital printout. Luminol-dependent chemiluminescence is influenced by the presence of contaminating red blood cells and by composition of the medium, particularly presence of phenol red. HEPES buffer and foetal calf serum. Whereas clinical comparisons of opsonic activity are easily performed, comparisons of cellular activity require a high and uniform standard of cell preparation, characterization and maintenance. PMID:7429554

  12. Effect of aggregated silver nanoparticles on luminol chemiluminescence system and its analytical application.

    PubMed

    Qi, Yingying; Li, Baoxin; Xiu, Furong

    2014-07-15

    We found that after silver nanoparticles (AgNPs) aggregated, its catalytic activity on luminol CL reaction obviously changed, and the change characteristic was closely related to the sizes of AgNPs. UV-visible spectra, X-ray photoelectron spectra, zeta potential and transmission electron microscopy studies were carried out to investigate the CL effect mechanism. The different CL responses of aggregated AgNPs with different size were suggested to be due to the two effects of quantum size and electron density in nanoparticle's conduction bands, and which one played a major role. The poisonous organic contaminants such as anilines, could induce the aggregation of AgNPs, were observed to affect effectively the luminol-H2O2-7 nm and 15 nm AgNPs CL systems and were detectable by use of a flow injection method with the enhanced or inhibited CL detection. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Enhanced electrochemiluminescence from luminol at carboxyl graphene for detection of α-fetoprotein.

    PubMed

    Li, Xiaojian; Guo, Qingfang; Cao, Wei; Li, Yueyun; Du, Bin; Wei, Qin

    2014-07-15

    In this study, a novel sensitive electrochemiluminescence (ECL) immunosensor was constructed by carboxyl graphene (GR) for enhancing luminol-O2 system emission. Here, carboxyl GR was used to enhance the ECL intensity of luminol that had excellent electron transfer ability and good solubility. The sensing platform was constructed by depositing carboxyl GR on electrodes and immobilizing antibodies on the surface of carboxyl GR through amidation. The specific immunoreaction between α-fetoprotein (AFP) and antibodies resulted in a decrease of ECL intensity, and the intensity decreased linearly with AFP concentrations in the range of 5 pg ml(-1) to 14 ng ml(-1) with a detection limit of 2.0 pg ml(-1). The proposed immunosensor exhibits high specificity, good reproducibility, and longtime stability. It may become a promising technique for protein detection. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Post-chemiluminescence determination of chloramphenicol based on luminol-potassium periodate system.

    PubMed

    Yang, Xiao Feng; Li, Nian Bing; Luo, Hong Qun

    2012-01-01

    A post-chemiluminescence (PCL) phenomenon was observed when chloramphenicol was injected into a mixture of luminol and potassium periodate after the chemiluminescence (CL) reaction of luminol-potassium periodate had finished. The possible reaction mechanism was proposed based on studies of the CL kinetic characteristics, the CL spectra, the fluorescence spectra and the UV-vis absorption spectra of the related substances. Based on the PCL reaction, a rapid and sensitive method for the determination of chloramphenicol was established. The linear response range was 6.0 × 10(-7) -1.0 × 10(-5) mol/L, with a correlation coefficient of 0.9986. The relative standard deviation (RSD) for 5.0 × 10(-6) mol/L chloramphenicol was 2.3% (n = 11). The detection limit was 1.6 × 10(-7) mol/L. The method has been applied to the determination of chloramphenicol in pharmaceutical samples with satisfactory results.

  15. [Carbamide peroxide as source of hydrogen peroxide for the luminol application at crime scenes].

    PubMed

    Schwarz, Lothar; Hermanowski, Mona-Lena

    2009-01-01

    The solution of hydrogen peroxide is a critical ingredient of the Weber luminol application for blood detection at the crime scene. An ideal alternative to the unstable hydrogen peroxide is a solid compound which is easy to transport, stable and quick to solve in water at the crime scene. Carbamide peroxide (urea peroxide) is one of these solid hydrogen peroxide carriers which is easy to obtain as one gram tablets. At dry conditions it is stable over a long period at room temperature and even for a short time at higher temperatures. But at 70 degrees C (180 degrees F) the tablets go out of shape and cake after one hour. In the application of luminol there are no differences between the use of hydrogen peroxide and carbamide peroxide.

  16. Decrease of luminol chemiluminescence upon exposure of human blood serum to 50 Hz electric fields.

    PubMed

    Calota, Violeta; Dragoiu, Simona; Meghea, Aurelia; Giurginca, Maria

    2006-09-01

    The chemiluminescence of luminol, after 1 and 2h in vitro exposure of human serum to 50 Hz electric fields of different intensities, decreases as compared to the controls. This indicates a field-induced decrease in the concentration of the free radicals. The report is limited to the key kinetic and field data, inviting independent kinetic analysis of the data in terms of reaction moments or reaction susceptibilities for the various normal modes indicated by the data.

  17. Actinometric measurement of j(O3-O(1D)) using a luminol detector

    NASA Astrophysics Data System (ADS)

    Bairai, Solomon T.; Stedman, Donald H.

    1992-10-01

    The photolysis frequency of ozone to singlet D oxygen atoms has been measured by means of a chemical actinometer using a luminol based detector. The instrument measures j(O3-O(1D)) with a precision of 10 percent. The data collected in winter and spring of 1991 is in agreement with model predictions and previously measured values. Data from a global solar radiometer can be used to estimate the effects of local cloudiness on j(O3-O(1D)).

  18. Clofibrate and dalargin increase luminol-dependent chemiluminescence of mouse blood.

    PubMed

    Mushtakova, V M; Rogovin, V V

    2007-09-01

    The effects of hypolipidemic drug clofibrate and polypeptide dalargin on activity of the neutrophil peroxidase system in mice were studied using the method of luminol-enhanced chemiluminescence. Clofibrate and dalargin increased the chemiluminescence of mouse whole blood. Their combined use several-fold potentiated this effect. It is expected that combined use of hypolipidemics and polypeptides will open a new trend in the search for stimulators of oxygen-dependent nonspecific immunity.

  19. A novel approach to obtaining reliable PCR results from luminol treated bloodstains.

    PubMed

    Della Manna, A; Montpetit, S

    2000-07-01

    In recent years the forensic scientist has been afforded great advances in technology both in the detection of latent bloodstains and in acquiring reliable DNA typing results from very small pieces of physical evidence. Scientists are now able to detect minute quantities of latent bloodstains by utilizing the luminol reagent, oftentimes indicating that an attempt has been made to conceal any evidence of bloodshed. With the introduction of PCR based technology to the forensic arena, scientists are now routinely able to obtain DNA typing results from previously insufficient amounts of biological material, items as small as a single hair, saliva on a cigarette butt, or a bloodstain the size of a pin head. We present here a merging of these two advances coupled with a new collection medium for post luminol treated latent bloodstains. The forensic scientist is now able to routinely isolate and recover an adequate amount of DNA suitable for PCR typing at all of the Promega GenePrint PowerPlex 1.1 loci. In this study, several dilutions of latent bloodstains were prepared in an effort to simulate transferred bloodstains that are routinely encountered in a crime scene setting. The latent bloodstains were treated with luminol and subsequently collected using conventional cotton tipped swabs as well as a Puritan sponge tipped swab. PCR typing at the Promega GenePrint PowerPlex 1.1 loci was then attempted upon all dilutions of the latent bloodstains for both collection mediums. The results clearly indicate that it is now routinely possible to recover adequate amounts of DNA suitable for PCR typing upon post luminol treated bloodstains.

  20. Actinometric measurement of j(O3-O(1D)) using a luminol detector

    NASA Technical Reports Server (NTRS)

    Bairai, Solomon T.; Stedman, Donald H.

    1992-01-01

    The photolysis frequency of ozone to singlet D oxygen atoms has been measured by means of a chemical actinometer using a luminol based detector. The instrument measures j(O3-O(1D)) with a precision of 10 percent. The data collected in winter and spring of 1991 is in agreement with model predictions and previously measured values. Data from a global solar radiometer can be used to estimate the effects of local cloudiness on j(O3-O(1D)).

  1. Pharmacokinetic of pseudoephedrine in rat serum with luminol-pepsin chemiluminescence system by flow injection analysis.

    PubMed

    Luo, Kai; Li, Yajuan; Zheng, Xiaohui; Song, Zhenghua

    2015-02-01

    Pepsin (Pep) accelerated the electron transferring rate of excited 3-aminophathlate and enhanced luminol-dissolved oxygen chemiluminescence (CL) intensity, and the flow injection (FI) luminol-Pep CL system was first developed. It was found that the CL intensity of luminol-Pep reaction could be remarkably inhibited by pseudoephedrine (PE); the decrement of CL intensity was linear to the logarithm of PE concentration in the range of 0.1∼100.0 nmol L(-1) with a detection limit of 0.03 nmol mL(-1) (3σ). At a flow rate of 2.0 mL min(-1), the complete process including washing and sampling was performed within 40 s, offering a sample throughput of 90 h(-1). This proposed method was successfully applied to determining PE in rat serum for 18 h after intragastric administration with the elimination ratio of 42.34 % and recoveries from 90.3 to 110.6 %. The pharmacokinetic results showed that PE could be rapidly absorbed into serum with peak concentration (C max) of 1.45 ± 0.18 g L(-1) at the time (T max) of 1.49 ± 0.02 h; the absorption half-life (0.35 ± 0.04 h), elimination half-life (1.86 ± 0.24 h), the area under curve (109.81 ± 6.03 mg L(-1) h(-1)), mean residence time (3.82 ± 0.27 h), and elimination rate constant (2.26 ± 0.23 L g(-1) h(-1)) in rats vivo were derived, respectively. The possible CL mechanism of luminol-Pep-PE reaction was discussed by FI-CL, fluorescence, and molecular docking (MD) methods.

  2. Effect of amino acids on luminol-dependent chemiluminescence generated by peripheral blood polymorphonuclear leukocytes.

    PubMed Central

    Minuk, G Y; Rascanin, N; Woods, D E

    1986-01-01

    Individual amino acids and amino acid mixtures caused a dose-dependent increase in chemiluminescence generated by peripheral blood polymorphonuclear leukocytes. A visual assay for opsonophagocytosis, however, failed to identify any quantitative differences between leukocytes incubated with amino acids and those incubated in amino-acid-free solutions. The results of this study suggest that the presence of amino acids may interfere with the proper interpretation of luminol-dependent chemiluminescence curves. PMID:3745427

  3. Enhancing effect of hydrazine on chemiluminescence of luminol-H2O2 system

    NASA Astrophysics Data System (ADS)

    Shukla, M.; Tiwari, A.; Brahme, N.; Kher, R. S.; Dhoble, S. J.

    2013-05-01

    Enhancement in chemiluminescence (CL) signals was obtained when an aqueous alkaline solution of hydrazine was mixed with a luminol-hydrogen peroxide system. The CL intensity is a linear function of hydrazine concentration over a range of 1-10 μg/ml. Several variables on the CL response were examined for the determination of optimum conditions for the system. A possible mechanism of the CL reaction is also discussed.

  4. Ceria Doped Zinc Oxide Nanoflowers Enhanced Luminol-Based Electrochemiluminescence Immunosensor for Amyloid-β Detection.

    PubMed

    Wang, Jing-Xi; Zhuo, Ying; Zhou, Ying; Wang, Hai-Jun; Yuan, Ruo; Chai, Ya-Qin

    2016-05-25

    In this work, ceria doped ZnO nanomaterials with flower-structure (Ce:ZONFs) were prepared to construct a luminol-based electrochemiluminescence (ECL) immunosensor for amyloid-β protein (Aβ) detection. Herein, carboxyl groups (-COOH) covered Ce:ZONFs were synthesized by a green method with lysine as reductant. After that, Ce:ZONFs-based ECL nanocomposite was prepared by combining the luminophore of luminol and Ce:ZONFs via amidation and physical absorption. Luminol modified on Ce:ZONFs surface could generate a strong ECL signal under the assistance of reactive oxygen species (ROSs) (such as OH(•) and O2(•-)), which were produced by a catalytic reaction between Ce:ZONFs and H2O2. It was worth noticing that a quick Ce(4+) ↔ Ce(3+) reaction in this doped material could increase the rate of electron transfer to realize the signal amplification. Subsequently, the luminol functionalized Ce:ZONFs (Ce:ZONFs-Lum) were covered by secondary antibody (Ab2) and glucose oxidase (GOD), respectively, to construct a novel Ab2 bioconjugate (Ab2-GOD@Ce:ZONFs-Lum). The wire-structured silver-cysteine complex (AgCys NWs) with a large number of -COOH, which was synthesized by AgNO3 and l-cysteine, was used as substrate of the immunosensor to capture the primary antibody (Ab1). Under the optimal conditions, this proposed ECL immunosensor had exhibited high sensitivity for Aβ detection with a wide linear range from 80 fg/mL to 100 ng/mL and an ultralow detection limit of 52 fg/mL. Meanwhile, this biosensor had good specificity for Aβ, indicating that the provided strategy had a promising potential in the detection of Aβ.

  5. Determination of postmortem interval from old skeletal remains by image analysis of luminol test results.

    PubMed

    Introna, F; Di Vella, G; Campobasso, C P

    1999-05-01

    The luminol test is routinely used in forensic serology to locate blood traces and identify blood stains not visible to the naked eye; its sensitivity is reported as ranging from 1:100,000 to 1:5,000,000. To evaluate the possibility of correlating the postmortem interval with blood remnants in bone tissue, the luminol test was performed on 80 femurs with a known time of death, grouped in five classes. Powdered bone (30 mg) was recovered from compact tissue of the mid-shaft of each femur and was treated with 0.1 mL of Luminol solution (Sirchie Finger Print Laboratories, Inc.). The reactions were observed in a dark room and filmed by a TV camera equipped with a recording tape. An intense chemiluminescence was observed after a few seconds in all 20 femurs with a PMI ranging from 1 month to 3 years. On the 20 femurs with a PMI ranging from 10-15 years, a clear chemiluminescence was visible with the naked eye in 80% of the sample. Among the 20 femurs with a PMI ranging from 25 to 35 years, a weaker chemiluminescence appeared in 7 femurs (33% of the sample). In the 10 femurs with a PMI ranging from 50 to 60 years, a faint reaction was observed only in a single femur. In none of the ten femurs with a PMI over 80 years was chemiluminescence observed. The image of each reaction was computerized and analyzed for gray scale. The results of image analysis show a possible quantitative relationship between the PMI and luminol chemiluminescence in powdered bone.

  6. Determination of Nitrite and Nitrate in Freshwaters using Flow Injection Luminol Chemiluminescence Detection.

    PubMed

    Rehman, Attiq-Ur; Yaqoob, Mohammad; Waseem, Amir; Nabi, Abdul

    2011-09-01

    A flow injection method for determination of nitrite and nitrate in freshwaters is described based on luminol-hypochlorite chemiluminescence (CL) system. Nitrate is reduced on-line with a cadmium reduction column to nitrite and its inhibition effect on luminol CL emission was measured. The effects of chemical and physical parameters such as buffer pH and concentration, luminol, sodium hypochlorite and sulfuric acid concentrations, flow rate, and sample volume were investigated. The calibration graphs were linear over the range 0.1-50 µM (R2 = 0.9989 and 0.9984) for nitrite and nitrate respectively with a limit of detection (S/N = 3) of 4.0 × 10-8 M and a sample throughput of 120 samples per hour. The effect of foreign ions was studied and the method was successfully applied to the determination of nitrite and nitrate in water samples. The results obtained were in good agreement with those achieved by a spectrophotometric reference method at the 95% confidence level. Standard addition method was also applied to the freshwater samples and the recovery values were found in the range of 92-109% and 94-105% for nitrite and nitrate respectively.

  7. Luminol electrochemiluminescence for the analysis of active cholesterol at the plasma membrane in single mammalian cells.

    PubMed

    Ma, Guangzhong; Zhou, Junyu; Tian, Chunxiu; Jiang, Dechen; Fang, Danjun; Chen, Hongyuan

    2013-04-16

    A luminol electrochemiluminescence assay was reported to analyze active cholesterol at the plasma membrane in single mammalian cells. The cellular membrane cholesterol was activated by the exposure of the cells to low ionic strength buffer or the inhibition of intracellular acyl-coA/cholesterol acyltransferase (ACAT). The active membrane cholesterol was reacted with cholesterol oxidase in the solution to generate a peak concentration of hydrogen peroxide on the electrode surface, which induced a measurable luminol electrochemiluminescence. Further treatment of the active cells with mevastatin decreased the active membrane cholesterol resulting in a drop in luminance. No change in the intracellular calcium was observed in the presence of luminol and voltage, which indicated that our analysis process might not interrupt the intracellular cholesterol trafficking. Single cell analysis was performed by placing a pinhole below the electrode so that only one cell was exposed to the photomultiplier tube (PMT). Twelve single cells were analyzed individually, and a large deviation on luminance ratio observed exhibited the cell heterogeneity on the active membrane cholesterol. The smaller deviation on ACAT/HMGCoA inhibited cells than ACAT inhibited cells suggested different inhibition efficiency for sandoz 58035 and mevastatin. The new information obtained from single cell analysis might provide a new insight on the study of intracellular cholesterol trafficking.

  8. Menadione-catalyzed luminol chemiluminescent assay for the viability of Escherichia coli ATCC 25922.

    PubMed

    Yamashoji, S; Takeda, M

    2001-01-01

    Escherichia coli ATCC 25922 produced O2- in the presence of menadione, and O2- -dependent luminol chemiluminescence intensity was proportional to colony-forming unit (CFU) in the exponential phase. CFU was determined by using a 96-well plate at a range of 3 X 10(3) to 8 x 10(7) CFU /well (0.1 ml) after a 10-min incubation with menadione, followed by chemiluminescent assay for 5 s. After a 4-hr incubation of E. coli (10(5) CFU/0.1 ml) with menadione and an antimicrobial agent inhibiting the synthesis of peptidoglycan, protein, and DNA, the inhibitory concentration (IC) of the antimicrobial agent determined by menadione-catalyzed luminol chemiluminescent assay was in good agreement with minimal inhibitory concentration (MIC) of the NCCLS (National Committee for Clinical Laboratory Standard) method requiring 18 hr. Menadione-catalyzed luminol chemiluminescent assay is expected to be useful for the rapid determination of cell viability under the conditions of various cell growths and stresses.

  9. [A comparison of the Bluestar and luminol effectiveness in bloodstain detection].

    PubMed

    łuczak, Sylwia; Woźniak, Marcin; Papuga, Marta; Stopińiska, Katarzyna; Sliwka, Karol

    2006-01-01

    The objective of the present study was to compare the effectiveness of two chemical agents--Bluestar and luminol--in detection of bloodstains. The experiments were performed to test for bloodstain detection sensitivity, chemical stability and to investigate the effect of both reagents on DNA typing. During this study, the authors prepared serial dilutions (1:2 to 1:10 000 000) of fresh blood, as well as dilutions of 25-year old blood on Whatman 3MM blotting paper. Additional dilutions of fresh blood were spotted on a glass surface. The experiments showed very similar results for both investigated reagents, although the Bluestar solution proved to be more stable (at least 7 days after the preparation) as compared to luminol (stable for not more than 24 hours). Both reagents showed a higher sensitivity for diluted bloodstains on a glass surface than for similar stains on filter paper. The investigators also demonstrated that multiplex amplification of DNA was feasible after Bluestar or luminol treatment, although the detected bloodstains might be too diluted to allow for effective DNA extraction and amplification.

  10. [Peripheral blood cells luminol-dependent chemiluminescence at the different stages of atopic dermatitis].

    PubMed

    Elistratova, I V; Morozov, S G; Zakharova, I A; Tarasova, M V

    2015-01-01

    Aim of this work was to record the luminol-dependent spontaneous and induced chemiluminescence at the different stages of atopic dermatitis. Peripheral blood cells were obtained from adult patient with atopic dermatitis followed by the registration of luminol-dependent chemiluminescence on luminograph. Opsonized zymosan as well as yeasts Candida tropicalis have been used to induce the chemiluminescence. Spontaneous and induced chemiluminescence were slightly elevated at the mild atopic dermatitis but were decreased at the severe stage of disease. Statistically significant difference has been found between group with mild and severe atopic dermatitis, Skin contamination by yeasts Candida tropicalis causes the increased level of blood cells chemiluminescence at the first week of atopic relapse when the disease was mild. Severe stage of atopic dermatitis was coupled with statistically significant inhibition of both, spontaneous and induced chemiluminescence. Luminol-dependent chemiluminescence of peripheral blood cells from adult atopic dermatitis patients may be stimulated at the mild stage and suppressed at severe stage of atopic dermatitis.

  11. Determination of picogram quantities of chlortoluron in soil samples by luminol-chitosan chemiluminescence system.

    PubMed

    Li, Yajuan; Zhang, Jingjing; Xiong, Xunyu; Luo, Kai; Guo, Jie; Shen, Minxia; Wang, Jiajia; Song, Zhenghua

    2014-01-01

    Based on the enhancing effect of chitosan (CS) on luminol-dissolved oxygen chemiluminescence (CL) reaction, a flow injection (FI) luminol-CS CL system was established. It was found that the increase of CL intensity was proportional to the concentrations of CS ranging from 0.7 to 10.0 μmol l(-1). In the presence of chlortoluron (CTU), the CL intensity of luminol-CS system could be obviously inhibited and the decrements of CL intensity were linearly proportional to the logarithm of CTU concentrations ranging from 0.01 to 70.0 ng ml(-1), giving the limit of detection 3.0 pg ml(-1) (3σ). At a flow rate of 2.0 ml min(-1), the whole process including sampling and washing could be accomplished within 36 s, offering a sample throughput of 100 h(-1). The proposed FI-CL method was successfully applied to the determination of CTU in soil samples with recoveries ranging from 95.0 % to 105.3 % and the relative standard deviations (RSDs) of less than 4.0 %.

  12. Luminol-amplified chemiluminescence: a sensitive method for detecting the carrier state in chronic granulomatous disease.

    PubMed Central

    Mills, E L; Rholl, K S; Quie, P G

    1980-01-01

    Patients with chronic granulomatous disease have a marked defect in neutrophil oxidative metabolism and microbicidal activity. Asymptomatic mothers of males with the disease can usually be identified as heterozygous carriers by intermediate leukocyte function. Most mothers of females with the disease, however, have normal leukocyte function, and the pattern of genetic transmission in these families has been difficult to establish. Of 14 mothers of males and females with chronic granulomatous disease, 10 had been found previously to have intermediate values for neutrophil bactericidal activity, oxygen consumption, hexose monophosphate shunt activity, and Nitro Blue Tetrazolium reduction, and 4 had normal in viro leukocyte function. In the present study, 4 of these 14 mothers had normal neutrophil bactericidal activity, 3 had normal zymosan-stimulated chemiluminescence, but none had normal luminol-amplified zymosan-stimulated chemiluminescence. The presence of luminol (5-amino-2,3-dehydro-1,4-phthalazinedione) in the phagocytic mixtures markedly increased the sensitivity of the assay, permitting detection of subtle defects in leukocyte oxidative metabolism in three previously unidentifiable carriers of the disease. Thus, luminol-amplified chemiluminescence appears to be one of the most sensitive methods available for detection of chronic granulomatous disease heterozygotes; the simplicity and reproducibility of the microtechnique permit evaluation of leukocyte function in infants and newborns. PMID:7419700

  13. Carbon nanofiber-based luminol-biotin probe for sensitive chemiluminescence detection of protein.

    PubMed

    Baj, Stefan; Krawczyk, Tomasz; Pradel, Natalia; Azam, Md Golam; Shibata, Takayuki; Dragusha, Shpend; Skutil, Krzysztof; Pawlyta, Miroslawa; Kai, Masaaki

    2014-01-01

    A carbon nanofiber-based luminol-biotin probe was synthesized for the sensitive chemiluminescence (CL) detection of a target protein by grafting luminol and biotin onto an oxidized carbon nanofiber. This carbon nanofiber was prepared by chemical vapor-deposition with methane in the presence of the Ni-Cu-MgO catalyst, which was followed by oxidization with HNO3-H2SO4 to produce a carboxyl group on the surface of the nanofiber. The material was grafted with luminol and biotin by means of a standard carbodiimide activation of COOH groups to produce corresponding amides. The substance was water-soluble and thus could be utilized as a sensitive CL probe for a protein assay. The probe showed highly specific affinity towards the biotin-labeled antibody via a streptavidin-biotin interaction. The detection limit for this model assay was approximately 0.2 pmol of the biotinized IgG spotted on a polyvinylidene fluoride (PVDF) membrane. Nonspecific binding to other proteins was not observed. Therefore, the synthesized carbon nanofiber-based CL probe may be useful for a sensitive and specific analysis of the target protein.

  14. Luminol chemiluminescence biosensor for glycated hemoglobin (HbA1c) in human blood samples.

    PubMed

    Ahn, Kwang-Soo; Lee, JungHoon; Park, Jong-Myeon; Choi, Han Nim; Lee, Won-Yong

    2016-01-15

    Luminol chemiluminescence (CL) biosensor based on boronic acid modified gold substrate has been developed for the determination of glycated hemoglobin (HbA1c) in human blood samples. In order to selectively capture HbA1c in sample, carboxy-EG6-undecanethiol was self-assembled on a gold thin-film substrate, followed by covalent coupling of 3-aminophenyl boronic acid (3-APBA). The captured HbA1c containing four iron heme groups plays as a catalyst for luminol CL reaction in the presence of hydrogen peroxide, and thus the luminol CL response is linearly proportional to the amount of HbA1c captured on the biosensor surface. The present biosensor showed linear dynamic range of HbA1c from 2.5% to 17.0%, which well covers the clinically important concentration range. In addition, the present biosensor exhibited negligible response to interfering species such as hemoglobin, fructose, and sorbitol. The present HbA1c biosensor was applied to the determination of HbA1c in human blood samples and the results were well agreed with that obtained with a conventional method.

  15. The electrochemiluminescence of luminol on titania nanotubes functionalised indium tin oxide glass for flow injection analysis.

    PubMed

    Zhao, Qun; Xiao, Changbin; Tu, Yifeng

    2015-10-01

    The titania nanotubes (TiNTs) had been immobilised onto the indium tin oxide (ITO) coated glass to intensify the electrochemiluminescence (ECL) of luminol. The morphology, structure and properties such as specific surface area and transmittance of synthesised TiNTs were characterised. The results indicated that the TiNTs was several hundred nanometres in length with the diameter of 20 nm. In flow injection analysis (FIA) mode, the TiNTs dramatically enhanced the ECL emission of luminol for about 25 multiple, meanwhile decreased the requirement of buffer pH and exciting potential. The ECL emission of luminol on functionalised ITO electrode has sensitive response toward hydrogen peroxide, and extraordinarily responsive toward the antioxidant. Under the optimal conditions, the ECL emission exhibited a linear response within the concentration range from 0.1 mg L(-1) to 30 mg L(-1) and an absolute detection limit of 1.65×10(-10) g of resveratrol. The gross antioxidant activity of blueberry and kiwi were determined with satisfactory recoveries. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Tyrosine-Specific Chemical Modification with in Situ Hemin-Activated Luminol Derivatives.

    PubMed

    Sato, Shinichi; Nakamura, Kosuke; Nakamura, Hiroyuki

    2015-11-20

    Tyrosine-specific chemical modification was achieved using in situ hemin-activated luminol derivatives. Tyrosine residues in peptide and protein were modified effectively with N-methylated luminol derivatives under oxidative conditions in the presence of hemin and H2O2. Both single and double modifications of the tyrosine residue occurred in the reaction of angiotensin II with N-methylated luminol derivative 9. Tyrosine-specific chemical modification of the model protein bovine serum albumin (BSA) revealed that the surface-exposed tyrosine residues were selectively modified with 9. We succeeded in the functionalization of several proteins using azide-conjugated compound 18 using alkyne-conjugated probes by copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) or dibenzocyclooctyne (DBCO)-mediated copper-free click chemistry. This tyrosine-specific modification was orthogonal to conventional lysine modification by N-hydroxysuccinimide (NHS) ester, and dual functionalization by fluorescence modification of tyrosine residues and PEG modification of lysine residues was achieved without affecting the modification efficiency.

  17. Microflow-injection chemiluminescence of luminol and hypochlorite enhanced by phloxine B.

    PubMed

    Song, Xiaoli; Shen, Hong; Yin, Xuefeng; Wang, Xiuzhong; Liu, Jinhua

    2013-01-01

    We report for the first time that the sensitivity of the luminol-hypochlorite chemiluminescence (CL) reaction was enhanced approximately 10 times by the addition of phloxine B. The maximum wavelength of CL emission shifted from 431 to 595 nm in the absence and presence, respectively, of phloxine B, suggesting that an efficient chemiluminescence resonance energy transfer occurred between a luminol donor and a phloxine B acceptor in the luminol-hypochlorite-phloxine B system. Based on this observation, a simple, rapid and sensitive microflow injection CL method, using a microchip with spiral channel configurations, was developed for the determination of hypochlorite. Under optimized conditions, a linear calibration curve (R(2) = 0.9944) over the range 0.1-10.0 µmol/L was obtained, with a detection limit of 0.025 µmol/L (S:N = 3). The relative standard deviation (RSD) was found to be 4.2% (n = 10) for 2.5 µmol/L hypochlorite. The sample consumption was only 2 μL, with a sample throughput of 90/h. The method has been used for determining trace amounts of hypochlorite in water samples with satisfactory results. Copyright © 2012 John Wiley & Sons, Ltd.

  18. A study of common interferences with the forensic luminol test for blood.

    PubMed

    Quickenden, T I; Creamer, J I

    2001-01-01

    A wide range of domestic and industrial substances that might be mistaken for haemoglobin in the forensic luminol test for blood were examined. The substances studied were in the categories of vegetable or fruit pulps and juices; domestic and commercial oils; cleaning agents; an insecticide; and various glues, paints and varnishes. A significant number of substances in each category gave luminescence intensities that were comparable with the intensities of undiluted haemoglobin, when sprayed with the standard forensic solution containing aqueous alkaline luminol and sodium perborate. In these cases the substance could be easily mistaken for blood when the luminol test is used, but in the remaining cases the luminescence intensity was so weak that it is unlikely that a false-positive test would be obtained. In a few cases the brightly emitting substance could be distinguished from blood by a small but detectable shift of the peak emission wavelength. The results indicated that particular care should be taken to avoid interferences when a crime scene is contaminated with parsnip, turnip or horseradish, and when surfaces coated with enamel paint are involved. To a lesser extent, some care should be taken when surfaces covered with terracotta or ceramic tiles, polyurethane varnishes or jute and sisal matting are involved.

  19. The forensic use of luminol chemiluminescence to detect traces of blood inside motor vehicles.

    PubMed

    Quickenden, T I; Ennis, C P; Creamer, J I

    2004-01-01

    The luminol test for blood was carried out on a set of interior fittings and surfaces inside three different makes of modern motor car. The surfaces and fittings provided little interference with the test for blood, although there was some detectable chemiluminescence when the test was applied to blood-free material from a seatbelt, a boot-lining and a gear-knob. The case with which haemoglobin samples could be washed off interior car surfaces was also examined for seat fabrics, carpets, roof-linings and various other plastic interior surfaces. A standard wash with water alone was not very effective and removed only ca. 50% of the haemoglobin. A standard wash with soapy water or with a proprietary multipurpose car cleaner removed ca. 90% of the haemoglobin from the tested surface. The effect of high car interior temperatures on haemoglobin samples that were subsequently used in the luminol test was also examined. It was shown that the sensitivity of the luminol test was not decreased but was increased by the prior heating of a haemoglobin sample. This effect was attributed to the thermal conversion of haemoglobin to the more brighter catalyst for chemiluminescence, methaemoglobin. The enthalpy of this conversion in the solid state was found to be 14.1 kJ/mol.

  20. [The effect of probiotic therapy on development of experimental obesity in rats caused by monosodium glutamate].

    PubMed

    Savcheniuk, O A; Virchenko, O V; Falalieieva, T M; Beregova, T V; Babenko, L P; Lazarenko, L M; Spivak, M Ia

    2014-01-01

    The effect of a mixture of probiotic strains (2:1:1 Lactobacillus casei IMVB-7280, Bifidobacterium animalis VKL, Bifidobacterium animalis VKB) on the development of experimental obesity in rats induced by neonatal administration of monosodium glutamate has been studied. It was shown that in rats of 4 months age, the injection of monosodium glutamate (4 mg/g) at 2, 4, 6, 8, 10 days after birth elicited abdominal obesity and metabolic syndrome. An intermittent administration of a probiotic mixture to rats treated with monosodium prevented the development of obesity. In the group of rats treated with probiotics, anthropometric parameters (weight and body length, Lee index, body mass index) did not differ from the level of intact rats. Visceral fat mass was decreased by probiotics by 38.5% (P < 0.05) compared to rats treated with water. Probiotics improved lipid metabolism: reduced the level of VLDL by 32.2% (P < 0,05), the level of LDL by 30.6% (P < 0.05), increased HDL by 25.7% (P <0,05) compared to obese control rats. Probiotic strains restored the secretion of adipocytes hormones (leptin and adiponectin) to the normal level of intact animals. The results show the effectiveness of probiotics for the prevention of obesity.

  1. Optimization of peroxynitrite-luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide.

    PubMed

    Chen, Shao L; Jian, Le; Lang, Hui Q

    2003-01-01

    We established a peroxynitrite-luminol chemiluminescence system for detecting peroxynitrite in cell culture solution exposed to carbon disulphide (CS(2)). Three factors, including exposure time to ozone (Factor A), volume of peroxynitrite (ONOO(-)) solution (Factor B) and luminol concentrations (Factor C) at three levels were selected and the combinations were in accordance with orthogonal design L(9) (3(4)). Peroxynitrite was generated from the reaction of ozone and 0.01 mol/L sodium azide (NaN(3)) dissolved in carbonic acid buffer solution (pH 11), and it was reacted with luminol to yield chemiluminescence. The peak value, peak time and kinetic curve of the light emission were observed. The selected combination conditions were 50 s ozone, 800 micro L peroxynitrite and 0.001 mol/L luminol solution. Cell culture solution with CS(2) enhanced the emission intensity of chemiluminescence (F = 8.38, p = 0.018) and shortened the peak time to chemiluminescence (F = 139.00, p = 0.0001). The data demonstrated that this luminol chemiluminescence system is suitable for detecting peroxynitrite in cell culture solutions for evaluating the effect of CS(2) on endothelial cells. Copyright 2003 John Wiley & Sons, Ltd.

  2. Sensitive electrochemiluminescence detection for CA15-3 based on immobilizing luminol on dendrimer functionalized ZnO nanorods.

    PubMed

    Jiang, Xinya; Wang, Haijun; Yuan, Ruo; Chai, Yaqin

    2015-01-15

    In this study, we constructed a novel electrochemiluminescence (ECL) immunosensor for sensitive and selective detection of carbohydrate antigen 15-3 (CA15-3) by using polyamidoamine (PAMAM)-functionalized ZnO nanorods (ZNs-PAMAM) as carriers. PAMAM dendrimers with hyper-branched and three-dimensional structure were used as linked reagents for co-immobilization of luminol and CA15-3 detection antibody on the ZNs to prepare the signal probe. In addition, ZNs could hasten the decomposition of H2O2 to generate various reactive oxygen species (ROSs) which accelerated the ECL reaction of luminol with amplified ECL intensity. Compared with luminol in the detection solution, the ECL efficiencies of luminol could be improved by immobilizing luminol on the electrode due to the smaller distance between luminescence reagent and the electrode surface. Moreover, the electrodepositing gold nanoparticles (AuNPs) on the bare glass carbon electrode (GCE) with enhanced surface area could capture a large amount of primary anti-CA15-3 to improve the sensitivity of the immunosensor. Under the optimized experimental conditions, a wide linear range of 0.1-120 U mL(-1) was acquired with a relatively low detection limit of 0.033 U mL(-1) (S/N=3) for CA15-3. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Microemulsion-enhanced electrochemiluminescence of luminol-H2O2 for sensitive flow injection analysis of antioxidant compounds.

    PubMed

    Xiuhua, Wei; Chao, Liu; Yifeng, Tu

    2012-05-30

    A microemulsion enhanced electrochemiluminescence (ECL) of luminol-H(2)O(2) was studied with the flow-injection (FI) technique. The results revealed that the microemulsion composed with cetyltrimethylammonium bromide (CTAB), n-butanol, n-heptane and water greatly enhanced the ECL especially in acidic medium. The ECL emission increased for 20 to 2 times in this microemulsion medium over the pH range of 5.0-8.0 compared to that in aqueous solution. The mechanism of enhancement of surfactant and microemulsion for luminol-H(2)O(2) ECL was discussed. It is mainly based on the electrostatic interaction between luminol anion and the head group of surfactant, which causes the adsorption and promotes the dissociation of luminol on the surfaces of the microemulsion droplets, favors the oxidation of luminol by the yielded reactive oxygen species (ROSs) during electrolysis. This research is very significant for ECL applications because of the extended practicable pH range which was suitable for environmental and biological systems. As an example, this FI-ECL technique can be applied for determination of oligo proanthocyanidin (OPC) because of its antioxidant property and to evaluate the total antioxidant activity of the grape skin using OPC as an index. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Label-free electrochemiluminescence immunosensor for cardiac troponin I using luminol functionalized gold nanoparticles as a sensing platform.

    PubMed

    Li, Fang; Yu, Yuqi; Cui, Hua; Yang, Di; Bian, Zhiping

    2013-03-21

    A simple and sensitive label-free electrochemiluminescence (ECL) immunosensor based on the use of luminol functionalized gold nanoparticles (luminol-AuNPs) as antibody carriers and sensing platform is described for detecting the acute myocardial infarction biomarker cTnI. The ECL immunosensor was fabricated by the assembly of luminol-AuNPs conjugated with biotinylated antibodies against cTnI (biotin-anti-cTnI-luminol-AuNPs) with the streptavidin coated AuNPs (SA-AuNPs) modified Au electrode directly by virtue of the biotin-SA system. The fabricated sensing platform exhibited stable and strong ECL intensity and could be used for the recognition of target antigen. In the presence of cTnI, a decrease in the ECL intensity was observed. Direct detection of the ECL signal changes during antigen-antibody immunoreactions can be used for the quantification of cTnI. The ECL response exhibited a quite wide dynamic range from 1000 ng mL(-1) down to 0.1 ng mL(-1). The proposed method has been successfully applied in the detection of cTnI in real plasma samples. This protocol is simple, fast, sensitive, specific, stable and reliable. This work reveals that the luminol-AuNPs are excellent sensing platforms for the fabrication of simple and sensitive immunosensors. Moreover, the proposed strategy may also be extended for the detection of other biomarkers, which is of great application potential in clinical and pharmaceutical analysis.

  5. Synthesis, characterization, and electrochemiluminescence of luminol-reduced gold nanoparticles and their application in a hydrogen peroxide sensor.

    PubMed

    Cui, Hua; Wang, Wei; Duan, Chun-Feng; Dong, Yong-Ping; Guo, Ji-Zhao

    2007-01-01

    It was found that chloroauric acid (HAuCl(4)) could be directly reduced by the luminescent reagent luminol in aqueous solution to form gold nanoparticles (AuNPs), the size of which depended on the amount of luminol. The morphology and surface state of as-prepared AuNPs were characterized by transmission electron microscopy, UV/visible spectroscopy, X-ray photoelectron spectroscopy, FTIR spectroscopy, and thermogravimetric analysis. All results indicated that residual luminol and its oxidation product 3-aminophthalate coexisted on the surface of AuNPs through the weak covalent interaction between gold and nitrogen atoms in their amino groups. Subsequently, a luminol-capped AuNP-modified electrode was fabricated by the immobilization of AuNPs on a gold electrode by virtue of cysteine molecules and then immersion in a luminol solution. The modified electrode was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy. The as-prepared modified electrode exhibited an electrochemiluminescence (ECL) response in alkaline aqueous solution under a double-step potential. H2O2 was found to enhance the ECL. On this basis, an ECL sensor for the detection of H2O2 was developed. The method is simple, fast, and reagent free. It is applicable to the determination of H2O2 in the range of 3x10(-7)-1x10(-3) mol L(-1) with a detection limit of 1x10(-7) mol L(-1) (S/N=3).

  6. The effect of lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response as assessed by luminol-amplified chemiluminescence in dairy cows

    USDA-ARS?s Scientific Manuscript database

    The differences between lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response using luminol-amplified chemiluminescence (CL) are currently unknown in cattle. Luminol-dependent CL measures the amount of reactive oxygen species released from leukocytes a...

  7. Menadione-catalyzed luminol luminescent assay as a novel evaluation method of ethanol tolerance in yeast cells.

    PubMed

    Yamashoji, Shiro

    2009-02-01

    In this study, ethanol inhibited the growth and glucose-induced proton release of yeast cells in a dose-dependent manner. On the other hand, ethanol tolerance of menadione-catalyzed luminol luminescence by yeast cells increased with increasing ethanol concentrations in the growth medium. The intracellular reduced-form nicotinamide adenine dinucleotide (NADH) concentration also increased with increasing ethanol concentrations in the medium and was enough to maintain constant menadione-catalyzed luminol luminescence. These facts suggest that the menadione-catalyzed luminol luminescent assay depending on a NADH:quinone reductase and NADH generation system is useful as a new evaluation assay for assessing the vitality of ethanol-stressed yeast cells, whereas the glucose-induced proton release assay is expected to be useful for the evaluation of cell growth under ethanol stress.

  8. Luminol-dependent photoemission from single neutrophil stimulated by phorbol ester and calcium ionophore--role of degranulation and myeloperoxidase

    SciTech Connect

    Suematsu, M.; Oshio, C.; Miura, S.; Suzuki, M.; Houzawa, S.; Tsuchiya, M.

    1988-08-30

    Luminol-dependent photonic burst from phorbol ester-treated single neutrophil was visually investigated by using an ultrasensitive photonic image intensifier microscope. Neutrophils stimulated by phorbol myristate acetate (0.1 microgram/ml) alone produced a negligible level of photonic activities in the presence of luminol (10 micrograms/ml). The additional application of 0.1 microM Ca2+ ionophore A23187 induced explosive changes of photonic burst corresponding to the distribution of neutrophils, and these photonic activities were gradually spread to extracellular space. Sodium azide, which prevents myeloperoxidase activity, inhibited Ca2+ ionophore-induced photonic burst from phorbol ester-treated neutrophil. These findings suggest a prerequisite role of degranulation and myeloperoxidase release in luminol-dependent photoemission from stimulated neutrophils.

  9. Enhanced electrochemiluminescence from luminol at multi-walled carbon nanotubes decorated with palladium nanoparticles: a novel route for the fabrication of an oxygen sensor and a glucose biosensor.

    PubMed

    Haghighi, Behzad; Bozorgzadeh, Somayyeh

    2011-07-04

    Incorporation of palladium nanoparticles on the surface of multi-walled carbon nanotubes and modification of glassy carbon electrode with the prepared nano-hybrid material led to the fabrication of a novel electrode. The modified electrode showed attractive electrocatalytic activity and sensitizing effect on luminol-O(2) and luminol-H(2)O(2) electrochemiluminescence (ECL) reactions at neutral media. The sensitized luminol-O(2) and luminol-H(2)O(2) reactions were successfully applied for the ECL determination of dissolved O(2) and glucose, respectively. Under the optimal conditions for luminol-O(2) system, the ECL signal intensity of luminol was linear with the concentration of dissolved oxygen in the range between 0.08 and 0.94 mM (r=0.9996) and for luminol-H(2)O(2) system, the ECL signal intensity of luminol was linear with the concentration of glucose in the range between 0.1 and 1000 μM (r=0.9998). The limits of detection (S/N=3) for dissolved oxygen and glucose were 0.02 mM and 54 nM, respectively. The relative standard deviations (RSD) for repetitive measurements of 0.50 mM oxygen (n=10) and 10 μM glucose (n=30) were 3.5% and 0.3%, respectively. Also, under the optimal conditions for luminol-H(2)O(2) system, the ECL signal intensity of luminol was linear with the concentration of H(2)O(2) in the range between 1 nM and 0.45 mM (r=0.9997). The limit of detection (S/N=3) for H(2)O(2) detection was 0.5 nM and the relative standard deviation for repetitive measurements of 10 μM H(2)O(2) (n=10) was 0.8%. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. A novel on-line gold nanoparticle-catalyzed luminol chemiluminescence detector for high-performance liquid chromatography.

    PubMed

    Zhang, Qun Lin; Wu, Liang; Lv, Chen; Zhang, Xiao Yue

    2012-06-15

    A novel on-line gold nanoparticle-catalyzed luminol-H(2)O(2) chemiluminescence (CL) detector for high-performance liquid chromatography (HPLC) was established, in which gold nanoparticles were produced by the on-line reaction of H(2)O(2), NaHCO(3)-Na(2)CO(3) (buffer solution of luminol), and HAuCl(4). Eight phenolic compounds (gallic acid, protocatechuic acid, protocatechuic aldehyde, 2,5-dihydroxybenzoic acid, caffeic acid, 2,3-dihydroxybenzoic acid, (+)-catechin, and (-)-epicatechin) were chosen as the model compounds. Every separated phenolic compound in the column eluent strongly enhanced the CL signal of on-line gold nanoparticle-catalyzed luminol system. The CL and UV-visible absorption spectra and transmission electron microscopy studies were carried out, and the CL enhancement mechanism was ascribed to that the presence of phenolic compound promoted the on-line formation of 38-nm-diameter gold nanoparticles, which better catalyzed the luminol-H(2)O(2) CL reaction. The effects of methanol and phosphoric acid in the proposed HPLC configuration were performed by two gradient elution programs, and the baseline profile revealed that on-line gold nanoparticle-catalyzed luminol-H(2)O(2) CL detector had better compatibility than 38 nm gold colloids-luminol-H(2)O(2) CL detector. The proposed CL detector exhibits excellent analytical performance with the low detection limit (S/N=3) of 0.53-0.97 ng/mL (10.6-19.4 pg) phenolic compounds, and offers a new strategy for developing on-line nanoparticle-catalyzed CL detector for HPLC with sensitive analysis. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Determination of Co(II) in plant tissue by microwave digestion and ion chromatography coupled with luminol/perborate or luminol/percarbonate chemiluminescence detection.

    PubMed

    Murillo Pulgarín, José A; García Bermejo, Luisa F; Carrasquero Durán, Armando

    2011-01-01

    The cobalt is an essential element for leguminous plants but may be harmful for other species; for that reason determination of Co(II) is very important for the management of polluted areas and for discover plants with capacity for the hyperaccumulation of heavy metals, which has produced a growing necessity of fast, sensitive and selective analytical techniques. To develop an analytical procedure for the determination of cobalt in plant tissue by coupling the ionic chromatography to the luminol-based chemiluminescence detection. The sample was digested in a mixture of concentrated nitric acid and hydrogen peroxide, using an microwave oven to dissolve the Co(II). The solution containing Co(II) ions was injected to an ionic chromatograph using oxalic acid as the eluent. The detection was based on the catalytic effect of Co(II) on the luminol chemiluminescence using perborate or percarbonate as oxidants. Experimental variables, such as concentrations, pH, flow rates and acid digestion conditions were optimised. Well-resolved chromatographic peaks were obtained. The height and area showed linear dependences with the Co(II) concentration, which were used to quantify the heavy metal, with recoveries up to 95%. The microwave irradiation (60  s) was sufficient for the complete mineralisation of 200  mg of sample, employing 2  mL of the acid mixture. The method was free from the interferences, requiring less than 12 minutes to complete the analysis. The method was simple and rapid for the determination of cobalt in plant tissue with detection limits comparable to those obtained with more sophisticated and expensive analytical equipment. Copyright © 2010 John Wiley & Sons, Ltd.

  12. Iodophenol blue-enhanced luminol chemiluminescence and its application to hydrogen peroxide and glucose detection.

    PubMed

    Yu, Dalong; Wang, Ping; Zhao, Yanjun; Fan, Aiping

    2016-01-01

    In this study, we found that iodophenol blue can enhance the weak chemiluminescence (CL) of luminol-H2O2 system. With the aid of CL spectral, electron spin resonance (ESR) spectral measurements and studies on the effects of various free radical scavengers on the iodophenol blue-enhanced luminol-H2O2 system, we speculated that iodophenol blue may react with H2O2 and oxygen to produce oxidizing radical species such as OH(•) and O2(•-) resulting the formation of (1)O2. The generated (1)O2 may react with luminol anion generating an unstable endoperoxide and subsequent 3-aminophthalate* (3-APA*). When the excited-state 3-APA returned to the ground-state, an enhanced CL was observed. Based on the H2O2 concentration dependence of the catalytic activity of iodophenol blue, a cheap, simple, sensitive CL assay for the determination of H2O2 was established. Under the optimum experimental conditions, a linear relationship between the relative CL intensity and H2O2 concentration in the range of 0.025-10 μM was obtained. As low as 14 nM H2O2 can be sensitively detected by using the proposed method. The relative standard deviation for 5, 1 and 0.25 μM H2O2 was 2.58%, 5.16% and 4.66%, respectively. By combining the glucose oxidase (GOx)-catalyzed oxidation reaction, CL detection of glucose was realized. The linear range of glucose detection was 0.1-30 μM with a detection limit of 0.06 μM. The proposed method has been applied to the detection of glucose in diluted serum. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. A comparative study of bovine blood and milk neutrophil functions with luminol-dependent chemiluminescence.

    PubMed

    Mehrzad, J; Dosogne, H; Vangroenweghe, F; Burvenich, C

    2001-01-01

    In this study, a technique was developed for the chemiluminescence (CL) measurement of bovine milk polymorphonuclear leukocytes (PMN). In the first study, the effects of cell number and the concentration of phorbol-12-myristate-13-acetate (PMA), luminol, latex bead particles, dimethyl sulphoxide (DMSO) and gelatin on the luminol-dependent cellular CL (LDCL) response were assessed with healthy cows in different stages of lactation. In the second study, the LDCL and in vitro bactericidal activity of blood and milk PMN towards Staphylococcus aureus was investigated. In general, the CL activity of blood PMN was consistently higher than that of milk PMN. We found that (a) the optimal cell density in blood and milk cells for maximal LDCL response ranged from 1.5 x 10(6) to 5 x 10(6) cells/mL; (b) the optimal concentrations of PMA, latex beads and luminol for maximal LDCL response were 100-200 ng/ml, 500 particles/PMN and 0.1 mmol/L, respectively. Concentrations of DMSO of 0.5-1% (v/v) did not significantly affect the maximal CL response of PMN. Gelatin concentrations of 0.1 -0.5 mg/ml had no effect on the LDCL of PMN. In addition, the LDCL of PMN was significantly correlated with bactericidal activity towards S. aureus (r = 0.78, p < 0.001 for blood PMN and r = 0.66, p < 0.01 for milk PMN). Under the optimal experimental conditions for measurement of CL produced by bovine blood and milk PMN defined in this study, LDCL assay is an accurate and reproducible technique for the rapid quantification of PMN bactericidal activity in physiological and pathological conditions of high-yielding dairy cows. Copyright 2001 John Wiley & Sons, Ltd.

  14. Fast gas chromotography with luminol detection for measurement of nitrogen dioxide and PANs.

    SciTech Connect

    Gaffney, J. S.; Marley, N. A.; Drayton, P. J.

    1999-09-30

    Fast capillary gas chromatography has been coupled to a luminol-based chemiluminescence detection system for the rapid monitoring of nitrogen dioxide and peroxyacyl nitrates. A first-generation instrument was described recently (Gaffney et al., 1998). This system is capable of monitoring nitrogen dioxide and peroxyacyl nitrates (PANs; to and including the C4 species) with 1-min time resolution. This is an improvement by a factor of five over gas chromatography methods with electron capture detection. In addition, the luminol method is substantially less expensive than laser fluorescent detection or mass spectroscopic methods. Applications in aircraft-based research have been published electronically and will appear shortly in Environmental Science and Technology (Gaffney et al., 1999a). An improved version of the instrument that has been designed and built makes use of a Hammamatsu photon-counting system. Detection limits of this instrumentation are at the low tens of ppt. The range of the instrument can be adjusted by modifying sampling volumes and detection counting times. A review of past work and of recent application of the instrumentation to field measurements of nitrogen dioxide and PANs is presented. The data clearly indicate that the luminol approach can determine the target species with time resolution of less than 1 min. Examples of applications for estimation of peroxyacetyl radical concentrations and nitrate radical formation rates are also presented. This instrumentation can further be used for evaluation of surfaces for loss of nitrogen dioxide and PANs, phenomena of possible importance for sampling interfaces and chamber wall design. Our high-frequency field data clearly indicate that the ''real world'' is not well mixed and that turbulent mixing and plume-edge chemistries might play an important role in urban- and regional-scale interactions. Dynamic flow systems might be required to evaluate such effects in new-generation chamber studies.

  15. A competitive immunoassay for sensitive detection of small molecules chloramphenicol based on luminol functionalized silver nanoprobe.

    PubMed

    Yu, Xiuxia; He, Yi; Jiang, Jie; Cui, Hua

    2014-02-17

    Chloramphenicol (CHL) as a broad-spectrum antibiotic has a broad action spectrum against Gram-positive and Gram-negative bacteria, as well as anaerobes. The use of CHL is strictly restricted in poultry because of its toxic effect. However, CHL is still illegally used in animal farming because of its accessibility and low cost. Therefore, sensitive methods are highly desired for the determination of CHL in foodstuffs. The immunoassays based on labeling as an important tool have been reported for the detection of CHL residues in food-producing animals. However, most of the labeling procedures require multi-step reactions and purifications and thus they are complicated and time-consuming. Recently, in our previous work, luminol functionalized silver nanoparticles have been successfully synthesized, which exhibits higher CL efficiency than luminol functionalized gold nanoparticles. In this work, the new luminol functionalized silver nanoparticles have been used for the labeling of small molecules CHL for the first time and a competitive chemiluminescent immunoassay has been developed for the detection of CHL. Owing to the amplification of silver nanoparticles, high sensitivity for CHL could be achieved with a low detection limit of 7.6×10(-9) g mL(-1) and a wide linear dynamic range of 1.0×10(-8)-1.0×10(-6) g mL(-1). This method has also been successfully applied to determine CHL in milk and honey samples with a good recoveries (92% and 102%, 99% and 107% respectively), indicating that the method is feasible for the determination of CHL in real milk and honey samples. The labeling procedure is simple, convenient and fast, superior to previously reported labeling procedures. The immunoassay is also simple, fast, sensitive and selective. It is of application potential for the determination of CHL in foodstuffs. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Investigation on the chemiluminescence reaction of the phenylhydrazine-luminol-peroxide system.

    PubMed

    Chandel, A L S; Khan, S A; Kher, R S; Tiwari, Ashish

    2012-01-01

    We studied the chemiluminescence (CL) oxidation of phenyl hydrazine-luminol with various organic and inorganic peroxides. Maximum CL intensity for this system was obtained for t-butylhydroperoxide. The enhancement in CL depended strongly on pH and was greatest at pH 12.5. The solvent drastically enhanced the CL intensity. DMSO was found to increase the CL intensity many-fold as compared to acetonitrile and water. The effect of temperature on CL intensity has also been studied. The CL spectra revealed a broad peak at 425 nm, which suggests excited 3-aminophthalate ion as the luminophor. A mechanism to explain the reactions is suggested.

  17. Effect of viruses on luminol-dependent chemiluminescence of human neutrophils.

    PubMed Central

    Faden, H; Sutyla, P; Ogra, P L

    1979-01-01

    The effects of Newcastle disease, herpes simplex, vaccinia, encephalomyocarditis, vesicular stomatitis and reoviruses on in vitro function of neutrophils were studied in Ficoll-Hypaque-separated polymorphonuclear leukocytes (PMN) employing the technique of luminol-dependent chemiluminescence. Newcastle disease, herpes simplex vaccinia, and reoviruses depressed chemiluminescence by 98, 65, 46, and 29%, respectively, while encephalomyocarditis and vesicular stomatitis viruses had no inhibitory effect. None of the viruses affected phagocytosis or PMN viability. These observations suggest significant alteration of neutrophil function by interaction with several viruses in in vitro settings. It is suggested that similar changes in PMN function may occur during in vivo viral infection. PMID:223982

  18. A luminol chemiluminescence method for sensing histidine and lysine using enzyme reactions.

    PubMed

    Kugimiya, Akimitsu; Fukada, Rie; Funamoto, Daiki

    2013-12-01

    The analysis of free amino acids in urine and plasma is useful for estimating disease status in clinical diagnoses. Changes in the concentration of free amino acids in foods are also useful markers of freshness, nutrition, and taste. In this study, the specific interaction between aminoacyl-tRNA synthetase (aaRS) and its corresponding amino acid was used to measure amino acid concentrations. Pyrophosphate released by the amino acid-aaRS binding reaction was detected by luminol chemiluminescence; the method provided selective quantitation of 1.0-30 μM histidine and 1.0-60 μM lysine. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. On the interaction of luminol with human serum albumin: Nature and thermodynamics of ligand binding

    NASA Astrophysics Data System (ADS)

    Moyon, N. Shaemningwar; Mitra, Sivaprasad

    2010-09-01

    The mechanism and thermodynamic parameters for the binding of luminol (LH 2) with human serum albumin was explored by steady state and picosecond time-resolved fluorescence spectroscopy. It was shown that out of two possible LH 2 conformers present is solution, only one is accessible for binding with HSA. The thermodynamic parameters like enthalpy (Δ H) and entropy (Δ S) change corresponding to the ligand binding process were also estimated by performing the experiment at different temperatures. The ligand replacement experiment with bilirubin confirms that LH 2 binds into the sub-domain IIA of the protein.

  20. Cerium complexes of cyclodextrin dimers as efficient catalysts for luminol chemiluminescence reactions.

    PubMed

    Yuan, De-Qi; Lu, Jianzhong; Atsumi, Masato; Yan, Jia-Ming; Kai, Masaaki; Fujita, Kahee

    2007-09-21

    The chemiluminescence of a luminol-H(2)O(2) system is found to be remarkably enhanced by the Ce(IV) complexes of EDTA-bridged cyclodextrin dimers. The dimers were proved to work much more efficiently than the corresponding monomer. The cavity shape of cyclodextrin moieties and their cooperation displayed an important role in amplifying the chemiluminescence. Further modification of either the cyclodextrin rims or the EDTA linker altered significantly the catalytic abilities of the cyclodextrin dimers, and the examination of the effect of substituents on the chemiluminescence outputs suggested that the proximity between the cyclodextrin cavity and the metallic center might account for the amelioration of the chemiluminescence output.

  1. ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #s 46000606120, 46000722120, AND 46000808120

    SciTech Connect

    Taylor-Pashow, K.

    2012-10-08

    Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot #s 46000706120, 46000722120, and 460008081120 qualification and verification samples met each of the selected specification requirements that were tested with the exception of a few pails being marginally below the lower weight percent solids limit. These deviations from the specifications are viewed as negligible since the corresponding density of the slurries indicates no appreciable shortage of MST solids. Therefore, SRNL recommends acceptance and use of these pails.

  2. SORPTION BEHAVIOR OF MONOSODIUM TITANATE AND AMORPHOUS PEROXOTITANATE MATERIALS UNDER WEAKLY ACIDIC CONDITIONS

    SciTech Connect

    Hobbs, D.; Elvington, M.; Click, D.

    2009-11-11

    Inorganic, titanate-based sorbents are tested with respect to adsorption of a variety of sorbates under weakly acidic conditions (pH 3). Specifically, monosodium titanate (MST) and amorphous peroxotitanate (APT) sorption characteristics are initially probed through a screening process consisting of a pair of mixed metal solutions containing a total of 29 sorbates including alkali metals, alkaline earth metals, transition metals, metalloids and nonmetals. MST and APT sorption characteristics are further analyzed individually with chromium(III) and cadmium(II) using a batch method at ambient laboratory temperature, varying concentrations of the sorbents and sorbates and contact times. Maximum sorbate loadings are obtained from the respective adsorption isotherms.

  3. The neurotoxic effect of monosodium glutamate (MSG) on the retinal ganglion cells of the albino rat.

    PubMed

    van Rijn, C M; Marani, E; Rietveld, W J

    1986-07-01

    Monosodium glutamate (MSG) administered postnatally to the albino rat causes extensive destruction of the retina. This MSG effect does not result in complete blindness. Ganglion cells surviving the MSG treatment are healthy and functional. Using retrogradely transported HRP and Nissl staining in whole mounted retinas, it was found that the ganglion cells left after MSG treatment are not smaller than those in controls, that these cells do not belong to one cell size group, and that no cells size group is selectively missed. The results explain why photic entrainment of MSG treated animals is still possible.

  4. CdTe quantum dots@luminol as signal amplification system for chrysoidine with chemiluminescence-chitosan/graphene oxide-magnetite-molecularly imprinting sensor

    NASA Astrophysics Data System (ADS)

    Duan, Huimin; Li, Leilei; Wang, Xiaojiao; Wang, Yanhui; Li, Jianbo; Luo, Chuannan

    2016-01-01

    A sensitive chemiluminescence (CL) sensor based on chemiluminescence resonance energy transfer (CRET) in CdTe quantum dots@luminol (CdTe QDs@luminol) nanomaterials combined with chitosan/graphene oxide-magnetite-molecularly imprinted polymer (Cs/GM-MIP) for sensing chrysoidine was developed. CdTe QDs@luminol was designed to not only amplify the signal of CL but also reduce luminol consumption in the detection of chrysoidine. On the basis of the abundant hydroxy and amino, Cs and graphene oxide were introduced into the GM-MIP to improve the adsorption ability. The adsorption capacities of chrysoidine by both Cs/GM-MIP and non-imprinted polymer (Cs/GM-NIP) were investigated, and the CdTe QDs@luminol and Cs/GM-MIP were characterized by UV-vis, FTIR, SEM and TEM. The proposed sensor can detect chrysoidine within a linear range of 1.0 × 10- 7 - 1.0 × 10- 5 mol/L with a detection limit of 3.2 × 10- 8 mol/L (3δ) due to considerable chemiluminescence signal enhancement of the CdTe quantum dots@luminol detector and the high selectivity of the Cs/GM-MIP system. Under the optimal conditions of CL, the CdTe QDs@luminol-Cs/GM-MIP-CL sensor was used for chrysoidine determination in samples with satisfactory recoveries in the range of 90-107%.

  5. Determination of thyroxine in pharmaceuticals using flow injection with luminol chemiluminescence inhibition detection.

    PubMed

    Waseem, Amir; Yaqoob, Mohammad; Nabi, Abdul

    2006-01-01

    A simple flow injection method is reported for the determination of thyroxine, based on its inhibition effect on luminol-iron(II) chemiluminescence in alkaline medium in the presence of molecular oxygen. The detection limits (2s) for d- and l-thyroxine are 0.08 and 0.1 mg/L, respectively, with a sample throughput of 100/h. The calibration data for d- and l-thyroxine over the range 0.2-1.0 mg/L gives correlation coefficients (r(2)) of 0.9915 and 0.984 with relative standard deviations (RSD; n = 4) in the range 1.2-2.8%. The effects of some organic compounds was studied on luminol-iron(II) CL system for thyroxine determination. The method was applied to pharmaceutical thyroxine tablets and the results obtained (in the range 50.5 +/- 2.0-51.6 +/- 1.2 microg l-thyroxine/tablet) were in reasonable agreement with the value quoted. Copyright (c) 2006 John Wiley & Sons, Ltd.

  6. Chemiluminescence detection of permanganate index (CODMn) by a luminol-KMnO4 based reaction.

    PubMed

    Tian, Jinjun; Hu, Yonggang; Zhang, Jie

    2008-01-01

    A novel chemiluminescence (CL) system for determination of permanganate index (CODMn) combined with flow injection analysis has been proposed in this study. On the basis of the chemiluminescent reaction of luminol-KMnO4 system, light emission caused by luminol-KMnO4 system was detected by the photomultiplier tube, and its intensity caused by the appearance of KMnO4 after sample digestion was inversely proportional to CODMn. Effects for CODMn determining such as pH, concentrations and interference were investigated in detail. A detection limit of 0.3 mg/L CODMn with a linear range of 0.3--200 mg/L for its theoretical CODMn was obtained under the optimized experimental conditions. The relative standard deviation was 4.3% for 5.0 mg/L CODMn (n = 11). This CL flow system for determining CODMn was simple, rapid, and suitable for automatic analysis. The data obtained by the present method were fairly in good agreement with those obtained by the standard titrimetric method. It has been applied to determine real samples with satisfactory results.

  7. Measurement of NAD(P)H oxidase-derived superoxide with the luminol analogue L-012.

    PubMed

    Daiber, Andreas; August, Michael; Baldus, Stephan; Wendt, Maria; Oelze, Matthias; Sydow, Karsten; Kleschyov, Andrei L; Munzel, Thomas

    2004-01-01

    In the present study we sought to determine the ability of the chemiluminescence dye 8-amino-5-chloro-7-phenylpyridol[3,4-d]pyridazine-1,4-(2H,3H)dione sodium salt (L-012) to detect superoxide in different biological systems. In human whole blood or isolated leukocytes, the sensitivity of the luminol analogue L-012 to detect superoxide was higher as compared with luminol, lucigenin, coelenterazine, and the fluorescence dye dihydroethidine. In isolated leukocytes as well as aortic rings from control (New Zealand White) and hyperlipidemic (Watanabe heritable hyperlipidemic) rabbits, L-012-enhanced chemiluminescence was successful in detecting differences in superoxide formation under basal conditions and on stimulation with the direct activator of protein kinase C, phorbol 12,13-dibutyrate (PDBu). The effects of PDBu were abrogated by gliotoxin and inhibitors of protein kinase C such as chelerythrine, identifying NAD(P)H oxidase as the significant superoxide source. Experiments using electron paramagnetic resonance and the spin trap 5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide revealed that in contrast to lucigenin, L-012 is not subject to redox cycling. These findings indicate that L-012-enhanced chemiluminescence represents a sensitive and reliable probe to detect superoxide in whole blood, inflammatory cells, and vascular tissue.

  8. The photodynamic effect: the comparison of chemiexcitation by luminol and phthalhydrazide.

    PubMed

    Bancirova, Martina; Lasovský, Jan

    2011-01-01

    The presence of light, oxygen and photosensitizer (organic dye) is required for the photodynamic effect. Light and photosensitizer are harmless by themselves, but when combined with oxygen, reactive oxygen species (ROS) can be produced. This photodynamic effect is used in photodynamic therapy (PDT); the production of ROS as lethal cytotoxic agents can inactivate tumor cells. However, during PDT, there are many difficulties, so it is not possible to excite the photosensitizer using a laser, a source of light at the wavelengths specific to the photosensitizer (in visible region of the spectrum). Chemiluminescence is the light emission as a result of a chemical reaction. It is possible to use a chemiluminescent mixture to excite the photosensitizer even if the light emission does not conform to the absorption maximum of the photosensitizer. Luciferin and luminol have been used as chemiluminescent compounds (energizers) for the excitation of the photosensitizers. The aim of this work was to compare the chemiexcitation of some selected photosensitizers (e.g. fluorescein, eosin, methylene blue, hypericin and phthalocyanines) by chemiluminescent mixtures containing luminol (high chemiluminescent quantum yield) or phthalhydrazide (low chemiluminescent quantum yield) on some Gram-positive (Enterococcus faecalis, Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa, E. coli) bacteria and some cell lines (NIH3T3 and MCF7). The efficiency of the chemiexcitation was dependent on the kind of the photosensitizer and on the type of the bacterial strain or cell line and was independent of the energizers. Copyright © 2010 John Wiley & Sons, Ltd.

  9. Catalytic effect of ferricyanide between myoglobin and luminol and effect of temperature.

    PubMed

    Gao, Xin; Liu, Yanhong; Song, Zhenghua

    2007-01-01

    Specific catalytic oxidation of oxymyoglobin (MbO(2)) and luminol by ferricyanide was studied in a flow-injection system. MbO(2) in different redox states (ferric and ferrous) was oxidized to Mb(Fe(III)) by ferricyanide, and then specific binding of the ferrocyanide anion to Mb(Fe(III)) to the His 119 (GH1) region accelerated the electron transfer between Mb(Fe(III)) and luminol, which produced a chemiluminescence (CL) signal at 425 nm. The increased CL emission was correlated with the myoglobin concentration in the range 0.16-7.5 microg/mL. Thermogravimetry and differential scanning calorimetry were used to investigate the temperature effects on this reaction. The results showed that the CL intensity in the presence of myoglobin changed considerably with heating in the range 15-50 degrees C, and the maximal CL intensity was observed at 40 degrees C, corresponding to the glass transition temperature of myoglobin. The effect of different ligands and interferences were also studied.

  10. Alloxan-induced luminol luminescence as a tool for investigating mechanisms of radical-mediated diabetogenicity.

    PubMed Central

    Grankvist, K

    1981-01-01

    Chemiluminescence of luminol in a cell-free system was used to investigate the mechanism of alloxan-dependent free-radical generation. In the presence of alloxan and reduced glutathione (GSH), luminescence was greatly stimulated by FeSO4. Replacing GSH by oxidized glutathione or NAD(P)(H), or replacing FeSO4 by CuSO4, ZNSO4 or FeCl3, did not yield chemiluminescence. The chemiluminescence of a mixture of alloxan. GSH, FeSO4 and luminol was inhibited by catalase, superoxide dismutase, scavengers of hydroxyl radicals (sodium benzoate, n-butanol, D-mannitol, dimethyl sulphoxide) or metal-ion chelators (EDTA, diethylenetriaminepenta-acetic acid, diethyldithiocarbamate. desferroxamine), D-glucose, L-glucose, D-mannose, D-fructose, 3-O-methyl-D-glucose, NAD+, NADH, NADP+ or NADPH, but not by urea or enzymically inactive superoxide dismutase. The results support the hypothesis that the diabetogenic action of alloxan is mediated by hydroxyl radicals generated in an iron-catalysed reaction. Protection against alloxan in vivo depends both on the chemical reactivity of protector with radicals or radical-generating systems and on the stereospecific requirement of some strategic site in the B-cell. PMID:7342976

  11. Self-assembly of organogels via new luminol imide derivatives: diverse nanostructures and substituent chain effect

    NASA Astrophysics Data System (ADS)

    Jiao, Tifeng; Huang, Qinqin; Zhang, Qingrui; Xiao, Debao; Zhou, Jingxin; Gao, Faming

    2013-06-01

    Luminol is considered as an efficient sycpstem in electrochemiluminescence (ECL) measurements for the detection of hydrogen peroxide. In this paper, new luminol imide derivatives with different alkyl substituent chains were designed and synthesized. Their gelation behaviors in 26 solvents were tested as novel low molecular mass organic gelators. It was shown that the length and number of alkyl substituent chains linked to a benzene ring in gelators played a crucial role in the gelation behavior of all compounds in various organic solvents. Longer alkyl chains in molecular skeletons in present gelators are favorable for the gelation of organic solvents. Scanning electron microscope and atomic force microscope observations revealed that the gelator molecules self-assemble into different micro/nanoscale aggregates from a dot, flower, belt, rod, and lamella to wrinkle with change of solvents. Spectral studies indicated that there existed different H-bond formations and hydrophobic forces, depending on the alkyl substituent chains in molecular skeletons. The present work may give some insight to the design and characteristic of new versatile soft materials and potential ECL biosensors with special molecular structures.

  12. Study on a Luminol-based Electrochemiluminescent Sensor for Label-Free DNA Sensing

    PubMed Central

    Chu, Hai-Hong; Yan, Ji-Lin; Tu, Yi-Feng

    2010-01-01

    Automatic, inexpensive, simple and sensitive methods for DNA sensing and quantification are highly desirable for biomedical research. The rapid development of both the fundamentals and applications of electrochemiluminescence (ECL) over the past years has demonstrated its potential for analytical and bio-analytical chemistry. This paper reports the quenching effect of DNA on the ECL of luminol and the further development of a DNA sensing device. With the pre-functionalization by a composite of carbon nano-tubes (CNTs) and Au nanoparticles (AuNPs), the sensor provides a novel and valuable label-free approach for DNA sensing. Here the ECL intensity was remarkably decreased when more than 1.0 × 10−12 molar of DNA were adsorbed on the sensor. Linearity of the DNA amount with the reciprocal of ECL intensity was observed. A saturated sensor caused a 92.8% quenching effect. The research also proposes the mechanism for the quenching effect which could be attributed to the interaction between luminol and DNA and the elimination of reactive oxygen species (ROSs) by DNA. PMID:22163421

  13. Zymosan-induced luminol-dependent chemiluminescence response of circulating and extravasated leukocytes in experimental sepsis.

    PubMed Central

    Khan, Haseeb Ahmad

    2004-01-01

    This study examines a concurrent profiling of circulating and extravasated polymorphonuclear leukocytes (PMNs) in a rat model of experimental sepsis. Fecal peritonitis was induced in Wistar male rats by intraperitoneal instillation of a fecal suspension in saline (1:1 w/v). Blood and peritoneal fluid were collected 8 h following fecal inoculation for the evaluation of inflammatory response of PMNs using zymosan-induced luminol-dependent chemiluminescence. Fifty microliters of pre-diluted blood or peritoneal fluid samples were mixed with 150 microl of reaction mixture (4 x 10(-4) M luminol+50 microg opsonized zymosan+0.1% gelatin in Hank's balanced salt solution) and the chemiluminescence signal was measured in a luminometer at 37 degrees C. Fecal peritonitis caused a significant leukocytopenia (3540+/-297 mm(-3) versus control value of 7525+/-711 mm(-3), p < 0.001) accompanied by massive infiltration of PMNs in the peritoneal cavity (34700+/-4006 versus 7325+/-425 mm(-3), p < 0.001). The phagocytic activity of circulating blood PMNs was down-regulated whereas a significant up-regulation was observed in the activity of PMNs from peritoneal fluid. In conclusion, this study clearly demonstrates sepsis-induced alterations in both blood and peritoneal fluid PMNs and their quantitative assessment may be helpful in disease evaluation and designing effective therapies. PMID:15203554

  14. Role of myeloperoxidase in luminol-dependent chemiluminescence of polymorphonuclear leukocytes.

    PubMed Central

    Dahlgren, C; Stendahl, O

    1983-01-01

    When polymorphonuclear leukocytes (PMNL) and soluble or particulate matter interact, the cells produce chemiluminescence, linked to activation of the oxidative metabolism of the cells. PMNL isolated from a patient with a myeloperoxidase deficiency were found to produce almost no luminol-dependent chemiluminescence, despite a pronounced production of superoxide anions (O2-). The chemotactic peptide formylmethionyl-leucyl-phenylalanine induced a two-peak chemiluminescence response in control PMNL. The response was modified, both in magnitude and in time-course, when the cells were incubated at 22 degrees C for 120 min. Addition of purified myeloperoxidase to the PMNL lacking this enzyme, before stimulus addition, resulted in a chemiluminescence response. In the response to formylmethionyl-leucyl-phenylalanine, only one peak, corresponding to the initial peak of control PMNL, was found. This indicated that luminol-dependent chemiluminescence is dependent on and directly related to the presence of myeloperoxidase in PMNL and that both intra- and extracellularly located myeloperoxidase has to be taken into account when interpreting the cellular response assayed as chemiluminescence. PMID:6299947

  15. In vitro screening of Fe2+-chelating effect by a Fenton's reaction-luminol chemiluminescence system.

    PubMed

    Wada, Mitsuhiro; Komatsu, Hiroaki; Ikeda, Rie; Aburjai, Talal A; Alkhalil, Suleiman M; Kuroda, Naotaka; Nakashima, Kenichiro

    2014-11-01

    In vitro screening of a Fe(2+) -chelating effect using a Fenton's reaction-luminol chemiluminescence (CL) system is described. The luminescence between the reactive oxygen species generated by the Fenton's reaction and luminol was decreased on capturing Fe(2+) using a chelator. The proposed method can prevent the consumption of expensive seed compounds (drug discovery candidates) owing to the high sensitivity of CL detection. Therefore, the assay could be performed using small volumes of sample solution (150 μL) at micromolar concentrations. After optimization of the screening conditions, the efficacies of conventional chelators such as ethylenediaminetetraacetic acid (EDTA), diethylentriaminepentaacetic acid (DETAPAC), deferoxamine, deferiprone and 1,10-phenanthroline were examined. EC50 values for these compounds (except 1,10-phenanthroline) were in the range 3.20 ± 0.87 to 9.57 ± 0.64 μM (n = 3). Rapid measurement of the Fe(2+)-chelating effect with an assay run time of a few minutes could be achieved using the proposed method. In addition, the specificity of the method was discussed. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Capillary gas chromatographic analysis of nitrogen dioxide and pans with luminol chemiluminescent detection.

    SciTech Connect

    Gaffney, J. S.; Bornick, R. M.; Chen, Y.-H.; Marley, N. A.; Environmental Research

    1998-01-01

    Peroxyacyl nitrates (PANs) and nitrogen dioxide are important atmospheric air pollutants in the troposphere. These atmospheric nitrogen species are strongly coupled chemically by a clearly temperature-dependent equilibrium in the troposphere. A chemical method that can measure both nitrogen dioxide and PANs rapidly and with sub-part-per-billion detection is described that is based upon a modified luminol detection system coupled to a capillary gas chromatographic column by using helium as a carrier. The system can readily separate and detect nitrogen dioxide, peroxyacetyl nitrate, peroxyproprionyl nitrate, and peroxybutyrl nitrate with detection limits in the low tens of parts per trillion with total analysis time of less than 1 min. Calibration of PAN by thermal decomposition to nitrogen dioxide is demonstrated with PAN detection sensitivities approximately 75% of the sensitivities observed for NO2 luminol detection by using helium as a carrier gas. The advantages of this method for simultaneous measurement of nitrogen dioxide and PANs over ozone chemiluminescent detection and electron capture detection are discussed, as well as potential applications of this method for heterogeneous surface chemistry studies of PANs and nitrogen dioxide and for tropospheric measurements.

  17. Intra- and extracellular events in luminol-dependent chemiluminescence of polymorphonuclear leukocytes.

    PubMed Central

    Briheim, G; Stendahl, O; Dahlgren, C

    1984-01-01

    When polymorphonuclear leukocytes (PMNL) and soluble or particulate matter interact, the cells produce chemiluminescence. Luminol-dependent light emission from PMNL is linked to the myeloperoxidase (MPO)-H2O2 system. Light emission from a cell-free MPO-H2O2 system was found to be totally inhibited by human serum albumin (HSA), and since HSA is a large molecular protein that does not readily gain access to intracellular sites of PMNL, it could be used to determine the importance of extra- and intracellular events in PMNL chemiluminescence. In studies with cells from an MPO-deficient patient, we found that HSA inhibited more than 90% of extracellularly produced chemiluminescence. The chemotactic peptide formylmethionyl-leucyl-phenylalanine induced a two-peak chemiluminescence response in normal PMNL, and addition of HSA reduced the first peak, whereas the second peak was unaffected. This result indicated that the first peak was a result of extracellular reactions and the second peak was a result of intracellular reactions of the MPO-H2O2 system. Most of the phorbol myristate acetate-induced response in normal PMNL was due to intracellular events. Furthermore, chemiluminescence of intracellular origin seems to be limited not by generation of oxidative metabolites but by diffusion of luminol into the cells. PMID:6329953

  18. Magnetic modulation of the chemiluminescence intensity in the oxidation of luminol by potassium ferricyanide

    SciTech Connect

    Tribel', M.M.; Frankevich, E.L.; Leksin, A.N.; Morozov, A.K.

    1986-04-01

    This paper attempts the experimental detection and investigation of the magnetic field-dependent radical steps in the oxidation of luminol by potassium ferricyanide. It was found that it is in fact possible to affect the chemiluminescence yield by the use of a low intensity magnetic field (ca 100 Oe) and to relate the observed effect to a hyperfine interaction in the radical pairs formed during the reaction. Solutions of LH/sub 2/ and K/sub 3/Fe (CN)/sub 6/ in alkaline aqueous solution (0.1 M NaOH) were delivered continuously through a mixer into an optical cuvette. A block diagram of the equipment is shown. The chemiluminescent light was directed through a light guide to an FEU-79 photoamplifier, protected by a special shield from the action of scattered magnetic fields. The derivative of the magnetic effect was examined and it was established that there is no deviation from saturation of the magnetic effect up to 3.5 kOe. The results demonstrate that in the stages preceding the formation of light emitter an interaction occurs between two paramagnetic particles. It is also shown that it is in principle possible to record the ESR spectrum of these luminol radicals with respect to the chemiluminescence, using the reaction-yield-detected magnetic resonance method.

  19. A biosensor for cholesterol based on gold nanoparticles-catalyzed luminol electrogenerated chemiluminescence.

    PubMed

    Zhang, Meihe; Yuan, Ruo; Chai, Yaqin; Chen, Shihong; Zhong, Huaan; Wang, Cun; Cheng, Yinfeng

    2012-02-15

    A novel cholesterol biosensor was prepared based on gold nanoparticles-catalyzed luminol electrogenerated chemiluminescence (ECL). Firstly, l-cysteine-reduced graphene oxide composites were modified on the surface of a glassy carbon electrode. Then, gold nanoparticles (AuNPs) were self-assembled on it. Subsequently, cholesterol oxidase (ChOx) was adsorbed on the surface of AuNPs to construct a cholesterol biosensor. The stepwise fabrication processes were characterized with cyclic voltammetry and atomic force microscopy. The ECL behaviors of the biosensor were also investigated. It was found that AuNPs not only provided larger surface area for higher ChOx loading but also formed the nano-structured interface on the electrode surface to improve the analytical performance of the ECL biosensor for cholesterol. Besides, based on the efficient catalytic ability of AuNPs to luminol ECL, the response of the biosensor to cholesterol was linear range from 3.3 μM to 1.0 mM with a detection limit of 1.1 μM (S/N=3). In addition, the prepared ECL biosensor exhibited satisfying reproducibility, stability and selectivity. Taking into account the advantages of ECL, we confidently expect that ECL would have potential applications in biotechnology and clinical diagnosis.

  20. Determination of asulam by fast stopped-flow chemiluminescence inhibition of luminol/peroxidase.

    PubMed

    García Sánchez, F; Navas Díaz, A; Delgado Téllez, C; Algarra, M

    2008-10-19

    An efficient, sensitive and fast stopped-flow method has been developed to determine asulam in water, based on its inhibition effect on the horseradish peroxidase-luminol-hydrogen peroxide chemiluminescence reaction, (HRP-luminol-H(2)O(2)). Ultra fast data acquisition (0.20s) facilitates excellent selectivity because no interferences from concomitants in the matrix act in such short time scale. The precision as repeatability (expressed as relative standard deviation, n=10) was 0.4% at a 40 pM level. The detection limit was 1.5 pM (0.35 ng/L) and 7.15 pM in pure and raw water, respectively. The calibration data over the range 5-60 pM present a correlation coefficient of r=0.9993. The proposed method has been applied to determine asulam in water samples by using solid-phase extraction (SPE). Mean recovery value was 98.1+/-2% at 50 pM level.

  1. Disposable luminol copolymer-based biosensor for uric acid in urine.

    PubMed

    Ballesta-Claver, J; Díaz Ortega, I F; Valencia-Mirón, M C; Capitán-Vallvey, L F

    2011-09-30

    A new electrochemiluminescent (ECL) disposable biosensor for uric acid was manufactured by immobilization in a double-layer design of luminol as a copolymer with 3,3',5,5'-tetramethylbenzidine (TMB) and the enzyme uricase in chitosan on gold screen-printed cells. The good mechanical and improved electroluminescent characteristics of the new copolymer poly(luminol-TMB) make it possible to determine uric acid by measuring the growing ECL emission with the analyte concentration. The combination of enzymatic selectivity with ECL sensitivity results in a disposable analytical device with a linear range for uric acid from 1.5×10(-6) to 1.0×10(-4) M, a limit of detection of 4.4×10(-7) M and a precision of 13.1% (1.0×10(-5) M, n=10) as relative standard deviation. Satisfactory results were obtained for uric acid determination in 24h-urine samples compared to a reference procedure. This uric acid biosensor can be used as a low-cost alternative to conventional methods.

  2. A ratiometric electrochemiluminescence detection for cancer cells using g-C3N4 nanosheets and Ag-PAMAM-luminol nanocomposites.

    PubMed

    Wang, Yin-Zhu; Hao, Nan; Feng, Qiu-Mei; Shi, Hai-Wei; Xu, Jing-Juan; Chen, Hong-Yuan

    2016-03-15

    In this work, a dual-signaling electrochemiluminescence (ECL) ratiometric sensing approach for the detection of HL-60 cancer cells was reported for the first time. G-C3N4 nanosheets and Ag-PAMAM-luminol nanocomposits (Ag-PAMAM-luminol NCs) were prepared and served as reductive-oxidative and oxidative-reductive ECL emitters respectively. DNA probe functionalized Ag-PAMAM-luminol NCs would hybridize with aptamers modified onto magnetic beads. In the presence of HL-60 cells, the aptamer would conjugate with the target cell and release Ag-PAMAM-luminol NCs. After magnetic separation, released Ag-PAMAM-luminol NCs would hybridize with capture DNA on g-C3N4 nanosheets. ECL from g-C3N4 nanosheets coated on ITO electrode at -1.25 V (vs SCE) could be quenched by Ag-PAMAM-luminol NCs due to the resonance energy transfer (RET) from g-C3N4 nanosheets to Ag NPs. Meanwhile, Ag-PAMAM-luminol brought the ECL signal of luminol at +0.45 V (vs SCE). Thus, the concentration of HL-60 cancer cells could be quantified by both the quenching of ECL from g-C3N4 nanosheets and the enhancement of ECL from luminol. By measuring the ratio of ECL intensities at two excitation potentials, this approach could achieve sensitive and reliable detection for cancer cells in a wide range from 200 cells/mL to 9000 cells/mL with the detection limit of 150 cells (S/N=3). Copyright © 2015 Elsevier B.V. All rights reserved.

  3. The combined luminol/isoluminol chemiluminescence method for differentiating between extracellular and intracellular oxidant production by neutrophils.

    PubMed

    Jancinová, Viera; Drábiková, Katarína; Nosál, Radomír; Racková, Lucia; Májeková, Magdaléna; Holománová, Dagmar

    2006-01-01

    To address the question why isoluminol, but not luminol, failed to detect oxidants produced intracellularly, differences between these luminophores were investigated with respect to physicochemical parameters and the character of chemiluminescence signal. Our results showed the isoluminol molecule to be more polar, more hydrophilic and possessing lower ability to form intramolecular bonds than the luminol molecule. Therefore, isoluminol: (i) only slightly pervaded biological membranes; (ii) depended essentially on extracellular peroxidase; (iii) did not produce chemiluminescence in the presence of extracellular scavengers; and (iv) it could be considered a specific detector of extracellular radicals. On the other hand, the physicochemical parameters of luminol and partial resistance of its chemiluminescence to the effect of extracellular inhibitors proved the lipo/hydrophilic character of this luminophore and thus its ability to interact with radicals both outside and inside of cells. The luminol chemiluminescence measured in the presence of extracellular scavengers and the isoluminol chemiluminescence were used with the intention to differentiate the effects of two antihistamine drugs on intra- and extracellular radical formation. In activated human neutrophils, brompheniramine inhibited the extracellular and potentiated the intracellular part of chemiluminescence signal, whereas a reducing effect of loratadine was observed in both compartments.

  4. Studies on PVP hydrogel-supported luminol chemiluminescence: 1. Kinetic and mechanistic aspects using multivariate factorial analysis.

    PubMed

    Bastos, Erick Leite; Ciscato, Luiz Francisco Monteiro Leite; Bartoloni, Fernando Heering; Catalani, Luiz Henrique; Baader, Wilhelm Josef

    2007-01-01

    The chemiluminescent oxidation of luminol by hydrogen peroxide in the presence of hemin is revisited in an UV-C cross-linked PVP hydrogel. Chemiluminescence properties such as initial light intensity (I(0)), area of emission (S) and observed rate constants (k(obs)) are studied, varying the concentration of all reactants using a multivariate factorial approach.

  5. Contribution of nitric oxide synthase to luminol-dependent chemiluminescence generated by phorbol-ester-activated Kupffer cells.

    PubMed Central

    Wang, J F; Komarov, P; Sies, H; de Groot, H

    1991-01-01

    Phorbol 12-myristate 13-acetate-induced luminol chemiluminescence in rat Kupffer cells was doubled by the addition of L-arginine and significantly (up to 70%) inhibited by NG-nitro-L-arginine and NG-monomethyl-L-arginine, competitive inhibitors of L-arginine-dependent nitric oxide (NO) formation. The release of superoxide anion (O2-) by NADPH oxidase was neither affected by L-arginine nor by the inhibitors. Only very slight luminol chemiluminescence was detectable in lipopolysaccharide-pretreated Kupffer cells, a condition in which significant amounts of NO were formed but no O2-. In a cell-free system, significant luminol chemiluminescence only occurred when both authentic NO and the O2-/H2O2- generating system xanthine/xanthine oxidase were present. The results indicate that luminol chemiluminescence in phorbol-ester-activated Kupffer cells largely depends on L-arginine metabolism by NO synthase, requiring the concurrent formation of NO and O2-/H2O2. PMID:1718262

  6. A comparative study of peroxidases from horse radish and Arthromyces ramosus as labels in luminol-mediated chemiluminescent assays.

    PubMed

    Kim, B B; Pisarev, V V; Egorov, A M

    1991-11-15

    The properties of a peroxidase from Arthromyces ramosus (ARP) in the chemiluminescent reaction of luminol oxidation have been studied. These were compared with the properties of horse radish peroxidase (HRP) in the cooxidation of luminol and p-iodophenol, the enhanced chemiluminescence (ECL) reaction. By means of the stop-flow technique, ARP was shown to have an enzymatic activity toward luminol higher than that toward HRP. ARP can efficiently catalyze luminol oxidation in the absence of substrate enhancer. pH and substrate concentrations were optimized to determine ARP with the highest sensitivity. The detection limit of ARP was 5 x 10(-13) M, the same as that for HRP in the ECL reaction. The data on the use of ARP as a label in enzyme immunoassay of human IgG are presented. ARP was shown to have all the advantages of HRP as a label in chemiluminescent enzyme immunoassays: (i) high signal intensity, (ii) slow decay of luminescence, (iii) high signal/noise ratio, and (iv) as a consequence of (i)-(iii), high detection sensitivity. However, the low thermostability of ARP can limit the potential fields of its application.

  7. A novel aptasensor for lysozyme based on electrogenerated chemiluminescence resonance energy transfer between luminol and silicon quantum dots.

    PubMed

    Dong, Yong-Ping; Wang, Jiao; Peng, Ying; Zhu, Jun-Jie

    2017-03-22

    In the present work, electrogenerated chemiluminescence (ECL) of luminol was investigated in neutral condition at a gold electrode in the presence of silicon quantum dots (SiQDs). The results revealed that SiQDs can not only greatly enhance luminol ECL, but also act as energy acceptor to construct a novel ECL resonance energy transfer (ECL-RET) system with luminol. As a result, strong anodic ECL signal was obtained in neutral condition at the bare gold electrode, which is suitable for biosensing application. Lysozyme exhibited apparent inhibiting effect on the ECL-RET system, based on which an ECL aptasensor was fabricated for the sensitive detection of lysozyme. The proposed method showed high sensitivity, good selectivity, and wide linearity for the detection of lysozyme in the range of 5.0×10(-14)-5.0×10(-9)gmL(-1) with a detection limit of 5.8×10(-15)gmL(-1) (3σ). The results suggested that as-proposed luminol/SiQDs ECL biosensor will be promising in the detection enzyme.

  8. OPTIMIZED MONOSODIUM TITANATE PHASE II SUPPLEMENTAL TESTING REPORT URANIUM ADSORPTION AND SHELF-LIFE MEASUREMENTS

    SciTech Connect

    Hobbs, D

    2008-01-01

    The DOE Office of Waste Processing recently funded supplemental Phase II testing to further investigate the uranium affinity and shelf-life of modified monosodium titanate (mMST). Testing results confirmed earlier findings that the mMST exhibits much lower affinity for uranium than the baseline monosodium titanate (MST) material. The loading of uranium onto the mMST sample measured more than an order of magnitude lower than that of the MST. This finding indicates that the use of mMST provides a significant advantage over MST in that the mMST will not concentrate enriched uranium to the degree that MST does. The reduced affinity of mMST for uranium allows more operational flexibility in treating waste solutions from a nuclear criticality safety perspective. Testing results also indicate that the mMST exhibits good shelf-life with no measurable loss in plutonium and neptunium removal upon storage of samples at ambient laboratory temperatures for up to 30-months. Testing did exhibit a change in strontium removal performance for both the mMST and MST samples at the most recent testing event. However, the decrease in strontium removal performance proved lower for the mMST than the MST sample. Given these positive findings SRNL recommends continued development of mMST as a replacement for MST in pretreatment facilities at the Savannah River Site (SRS).

  9. Study on Enhancement Principle and Stabilization for the Luminol-H2O2-HRP Chemiluminescence System

    PubMed Central

    Yang, Lihua; Jin, Maojun; Du, Pengfei; Chen, Ge; Zhang, Chan; Wang, Jian; Jin, Fen; Shao, Hua; She, Yongxin; Wang, Shanshan; Zheng, Lufei; Wang, Jing

    2015-01-01

    A luminol-H2O2-HRP chemiluminescence system with high relative luminescent intensity (RLU) and long stabilization time was investigated. First, the comparative study on the enhancement effect of ten compounds as enhancers to the luminol-H2O2-HRP chemiluminescence system was carried out, and the results showed that 4-(imidazol-1-yl)phenol (4-IMP), 4-iodophenol (4-IOP), 4-bromophenol (4-BOP) and 4-hydroxy-4’-iodobiphenyl (HIOP) had the best performance. Based on the experiment, the four enhancers were dissolved in acetone, acetonitrile, methanol, and dimethylformamide (DMF) with various concentrations, the results indicated that 4-IMP, 4-IOP, 4-BOP and HIOP dissolved in DMF with the concentrations of 0.2%, 3.2%, 1.6% and 3.2% could get the highest RLU values. Subsequently, the influences of pH, ionic strength, HRP, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol on the stabilization of the luminol-H2O2-HRP chemiluminescence system were studied, and we found that pH value, ionic strength, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol have little influence on luminescent stabilization, while HRP has a great influence. In different ranges of HRP concentration, different enhancers should be selected. When the concentration is within the range of 0~6 ng/mL, 4-IMP should be selected. When the concentration of HRP ranges from 6 to 25ng/mL, 4-IOP was the best choice. And when the concentration is within the range of 25~80 ng/mL, HIOP should be selected as the enhancer. Finally, the three well-performing chemiluminescent enhanced solutions (CESs) have been further optimized according to the three enhancers (4-IMP, 4-IOP and HIOP) in their utilized HRP concentration ranges. PMID:26154162

  10. Differential effects of luminol, nickel, and arsenite on the rejoining of ultraviolet light and alkylation-induced DNA breaks

    SciTech Connect

    Lee-Chen, S.F.; Yu, C.T.; Wu, D.R.

    1994-12-31

    When Chinese hamster ovary cells were treated with ultraviolet (UV) light or methyl methane-sulfonate (MMS), a large number of DNA strand breaks could be detected by alkaline elution. These strand breaks gradually disappeared if the treated cells were allowed to recover in a drug-free medium. The presence of nickel or arsenite during the recovery incubation retarded the disappearance of UV-induced strand breaks, whereas the disappearance of MMS-induced strand breaks was retarded by the presence of arsenite or of luminol, a new inhibit for poly(ADP-ribose) synthetase. Luminol, however, had no apparent effect on the repair of UV-induced DNA strand breaks, and nickel had no effect on the repair of MMS-induced DNA strand breaks. When UV- or MMS-treated cells were incubated in cytosine arabinofuranoside (AraC) plus hydroxyurea (HU), a large amount of low molecular weight DNA was detected by alkaline sucrose sedimentation. The molecular weight of these DNAs increased if the cells were further incubated in a drug-free medium. This rejoining of breaks in cells pretreated with UV plus AraC and HU was inhibited by nickel and by arsenite, but not by luminol. The rejoining of breaks in cells pretreated with MMS plus AraC and HU was inhibited by luminol and by arsenite, but not by nickel. These results suggest that different enzymes may be used in DNA resynthesis and/or ligation during the repairing of UV- and MMS-induced DNA strand breaks, and that nickel, luminol, and arsenite may have differential inhibitory effects on these enzymes. 29 refs., 4 figs., 1 tab.

  11. Study on Enhancement Principle and Stabilization for the Luminol-H2O2-HRP Chemiluminescence System.

    PubMed

    Yang, Lihua; Jin, Maojun; Du, Pengfei; Chen, Ge; Zhang, Chan; Wang, Jian; Jin, Fen; Shao, Hua; She, Yongxin; Wang, Shanshan; Zheng, Lufei; Wang, Jing

    2015-01-01

    A luminol-H2O2-HRP chemiluminescence system with high relative luminescent intensity (RLU) and long stabilization time was investigated. First, the comparative study on the enhancement effect of ten compounds as enhancers to the luminol-H2O2-HRP chemiluminescence system was carried out, and the results showed that 4-(imidazol-1-yl)phenol (4-IMP), 4-iodophenol (4-IOP), 4-bromophenol (4-BOP) and 4-hydroxy-4'-iodobiphenyl (HIOP) had the best performance. Based on the experiment, the four enhancers were dissolved in acetone, acetonitrile, methanol, and dimethylformamide (DMF) with various concentrations, the results indicated that 4-IMP, 4-IOP, 4-BOP and HIOP dissolved in DMF with the concentrations of 0.2%, 3.2%, 1.6% and 3.2% could get the highest RLU values. Subsequently, the influences of pH, ionic strength, HRP, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol on the stabilization of the luminol-H2O2-HRP chemiluminescence system were studied, and we found that pH value, ionic strength, 4-IMP, 4-IOP, 4-BOP, HIOP, H2O2 and luminol have little influence on luminescent stabilization, while HRP has a great influence. In different ranges of HRP concentration, different enhancers should be selected. When the concentration is within the range of 0~6 ng/mL, 4-IMP should be selected. When the concentration of HRP ranges from 6 to 25 ng/mL, 4-IOP was the best choice. And when the concentration is within the range of 25~80 ng/mL, HIOP should be selected as the enhancer. Finally, the three well-performing chemiluminescent enhanced solutions (CESs) have been further optimized according to the three enhancers (4-IMP, 4-IOP and HIOP) in their utilized HRP concentration ranges.

  12. A time period study on the efficiency of luminol in the detection of bloodstains concealed by paint on different surfaces.

    PubMed

    Nagesh, Deepthi; Ghosh, Shayani

    2017-02-11

    Forensic Science is the application of science to the criminal and civil laws that are enforced by police agencies in a criminal justice system. It is a science which relies on physical evidence; one of the important physical evidences being blood. The purpose of this research was to determine the efficacy of luminol reagent in detecting bloodstains on different surfaces, concealed by multiple layers of paint, over a period of time and also to compare the intensities of chemiluminescence exhibited by them. In this study, dry wall, wooden planks and metal surfaces were identified as commonly encountered surfaces at crime scenes and hence 25 of each surface were simulated and blood was spattered, which were then concealed by progressive layers of paint specific to each surface. Thereafter, each surface was critically observed for the intensity of chemiluminescence, following the application of luminol and the results were documented as photographs. The research was conducted for duration of 50 days, in order to study the effect of ageing of concealment upon detection of bloodstains using luminol. Varying intensities of chemiluminescence were displayed by all the three simulated surfaces deposited with paint over bloodstains up to three layers of concealment, depending on the nature of the surface which were captured using photography. The highest intensity of chemiluminescence was shown by concealed bloodstains on dry wall and metal surfaces, despite the number of layers of concealment. However, an increase in the number of layers of concealment produced a significant decrease in the intensity of chemiluminescenece displayed by the bloodstains concealed by paint upon reacting with luminol on metal sheets, which was not found to be uniform and consistent on the other surfaces. These findings highlight the fact that bloodstains concealed by paint could be effectively detected by luminol reagent, despite the nature and ageing of concealment and thereby provide a lead to

  13. Quality control of reactive oxygen species measurement by luminol-dependent chemiluminescence assay.

    PubMed

    Kobayashi, H; Gil-Guzman, E; Mahran, A M; Rakesh; Nelson, D R; Thomas, A J; Agarwa, A

    2001-01-01

    A total of 28 donor semen samples were used to evaluate the characteristics of laboratory variability in measuring reactive oxygen species (ROS). The objectives of this study were to assess the interassay (same sample observed on different days by the same observers) variability; interdonor, intraobserver (replications of the same sample on the same day) variability; and interobserver (multiple observers on the same day with the same sample) variability of the luminol-dependent chemiluminescence assay and to establish an optimal semen age and sperm concentration. Semen samples were collected from 6 healthy donors for 108 measures of ROS. ROS levels were measured by the assay using luminol as the probe. An additional assessment measured the effect of time (age of the sample) on ROS production in 12 donor samples at 60, 120, 180, and 240 minutes after the specimen was produced. Last, to evaluate the effect of sperm concentration on ROS production, ROS levels were measured in 10 donor sample aliquots with sperm concentrations ranging from 1 to 120 x 10(6)/mL. In the controls, the mean ROS level was 0.218 x 10(6) counted photons per minute; the interassay variability standard deviation (SD) was 0.077. The interobserver SD was 0.002 for an interobserver reliability of 97.5% (coefficient of variation [CV] = 0.9%). The intraobserver (between replication) SD was 0.001 for an intraobserver reliability of 98.7% (CV = 0.5%). The interassay SD was 0.005 for an interassay reliability of 93.8% (CV = 2.0%). There was no statistically significant interobserver, intraobserver, or interassay variation (P > .80). ROS levels decreased significantly with time; a dramatic decline in ROS production was seen in the specimens that were more than 60 minutes old (P < .001). ROS values decreased by 31% at 120 minutes and 62% at 180 minutes compared with the 60-minute-old specimens. A linear relationship was seen between the ROS levels and sperm concentration in 8 of the 10 samples analyzed (R

  14. Influence of pH upon surface-enhanced enzyme-catalyzed luminol chemiluminescence at vicinity of nanoscale-corrugated gold and silver films.

    PubMed

    Ou, Meigui; Lu, Guowei; Shen, Hong; Descamps, Armel; Marquette, Christophe André; Blum, Loïc Jacques; Roux, Stéphane; Tillement, Olivier; Cheng, Bolin; Perriat, Pascal

    2008-01-01

    Au and Ag biochips were fabricated to investigate the influence of pH upon the chemiluminescence (CL) of luminol at vicinity of surface-adsorbed peroxidase. A nanoscaled-corrugation of the metal induces an enhancement of the luminol CL which is maximal in the pH range favoring peroxidase catalysis and greater for gold than for silver. This is the proof that, in the CL process, the reactions involving peroxidase are surface-enhanced near corrugated surfaces.

  15. Artemisinin-Luminol Chemiluminescence for Forensic Bloodstain Detection Using a Smart Phone as a Detector.

    PubMed

    Gao, Wenyue; Wang, Chao; Muzyka, Kateryna; Kitte, Shimeles Addisu; Li, Jianping; Zhang, Wei; Xu, Guobao

    2017-06-06

    Forensic luminol chemiluminescence test is one of the most sensitive and popular methods for the determination of latent bloodstains. It mainly uses hydrogen peroxide or sodium perborate as coreactants. The easy decomposition of hydrogen peroxide and sodium perborate in the presence of many ions significantly affects the selectivity. Artemisinin is a natural peroxide that is quite stable in the presence of common ions. In the present study, artemisinin has been exploited for the forensic bloodstain chemiluminescence detection for the first time. Using smart phone as cost-effective portable detector, the visual detection of bloodstains has been achieved with a dilution factor of blood up to 100 000. Moreover, this system shows excellent selectivity against many common species. It can well differentiate bloodstains from other stains, such as coffee, brown sugar, and black tea. Both favorable sensitivity and selectivity makes the present method promising in forensic detection.

  16. Interaction of metals with peroxidase--mediated luminol-enhanced, chemiluminescence (PLmCL).

    PubMed

    Coteur, G; Dubois, P

    2004-01-01

    The peroxidase-mediated luminol-enhanced chemiluminescence (PLmCL) method has been used to study the in vitro effect of contaminants such as heavy metals on the reactive oxygen species production by immunocytes. We were interested to know whether metals could directly affect peroxidase-mediated luminescence, taking horseradish peroxidase (HRP) as a model enzyme, since this could contribute to the inhibition of immunocyte LmCL. Copper inhibited PLmCL in a dose-dependent manner, while cadmium, iron, silver and lead only partly decreased the signal in the concentration range tested. In contrast, zinc enhanced the signal at high concentrations. Eventually, chromium, mercury and aluminium did not affect PLmCL. It is suggested that these effects reflect the ability of the metals to interact with the active site of the peroxidase. These results demonstrate that such interactions have to be considered when interpreting the effects of metals on immunocytes using the LmCL method.

  17. Inhibition and enhancement by organic compounds of luminol-KIO4-H2O2 chemiluminescence.

    PubMed

    Xu, Hong; Duan, Chun-Feng; Lai, Chun-Ze; Lian, Mei; Zhang, Zhi-Feng; Liu, Li-Juan; Cui, Hua

    2006-01-01

    The effects of 36 organic compounds on luminol-KIO(4)-H(2)O(2) chemiluminescence (CL) were studied. It was found that most of the tested compounds could inhibit or enhance the CL intensity. The activities of such inhibitors or enhancers were related to the pH of the CL system and the number and position of functional groups such as -OH and -NH(2) on aromatic rings. The mechanism of the CL inhibition and enhancement was considered. Based on the CL inhibition or enhancement, the possibility of analytical applications was explored. The results demonstrated that numerous compounds were detectable at the ng/mL level using the CL system. Copyright (c) 2006 John Wiley & Sons, Ltd.

  18. Photodegradation and flow-injection determination of simetryn herbicide by luminol chemiluminescence detection.

    PubMed

    Waseem, Amir; Yaqoob, Mohammad; Nabi, Abdul

    2008-08-01

    A novel and simple flow injection chemiluminescence method is reported for the determination of simetryn, a common herbicide. The method is based on the direct oxidation of luminol by the photoproducts of the simetryn in alkaline medium in the absence of catalyst/oxidant. The linear concentration range was 0.01 - 2 microg mL(-1) simetryn with a correlation coefficient (r(2)) of 0.9997 and relative standard deviations (RSD; n = 4) in the range of 0.9 - 2.3%. The limit of detection (S/N = 3) was 7.5 ng mL(-1) with a sample throughput of 100 h(-1). The proposed method has been applied to determine simetryn in natural waters using Sep-Pak C(18) cartridges for solid phase extraction (SPE) procedure. The recoveries were in the range of 97 +/- 1 to 104 +/- 2%. The mechanism of chemiluminescence reaction has also been discussed briefly.

  19. A competitive luminol chemiluminescence immunosensor based on a microfluidic chip for the determination of ractopamine.

    PubMed

    Wang, Sai; Chen, Qilong; Wei, Xiao; Wu, Jian; Wang, Chunyan; Liu, Jiahui; Zhang, Liya; Dong, Yiyang

    2017-01-01

    Herein, a competitive luminol chemiluminescence immunosensor based on a microfluidic chip was developed to detect ractopamine (RCT) both in phosphate buffer and swine urine samples. The immunosensor can provide a liner range of 0.5-40 ng/mL and a high sensitivity with a limit of detection of 0.97 ng/mL for RCT detection in swine urine. Good rates of recovery in negative swine urine samples were achieved over the RCT concentration ranging from 0.5 to 40 ng/mL. The proposed method offered a promising analytical scheme for the on-site determination of RCT. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Sensitive determination of carbidopa through the electrochemiluminescence of luminol at graphene-modified electrodes.

    PubMed

    Hosseini, Morteza; Mirzanasiri, Nooshin; Rezapour, Morteza; Sheikhha, Mohammad Hasan; Faridbod, Farnoush; Norouzi, Parviz; Ganjali, Mohammad Reza

    2015-06-01

    Using the concept of electrogenerated chemiluminescence (ECL), a sensitive analytical method for the determination of carbidopa is described. Electro-oxidation of carbidopa on the surface of a graphene oxide (GO)-modified gold electrode (GE) leads to enhancement of the weak emission of oxidized luminol. Under optimum experimental conditions, the ECL signal increases linearly with increasing carbidopa concentrations over a range of 1.0 × 10(-9) -1.7 × 10(-7)  M, with a detection limit of 7.4 × 10(-10)  M. The proposed ECL method was successfully used for the determination of carbidopa in urine samples. Copyright © 2014 John Wiley & Sons, Ltd.

  1. [The effect of norfloxacin on the luminol-dependent chemiluminescence and adhesion of leukocytes].

    PubMed

    Iordanova, A I; Smolkina, T V; Nikitin, A V

    1995-05-01

    The in vitro effect of norfloxacin on the luminol-dependent chemiluminescence and adherence of polymorphonuclear leukocytes of guinea pigs was studied with the use of a wide range of the drug concentrations from 0.1 to 100 micrograms/ml under two different conditions, i.e. during the cell incubation in the presence of norfloxacin various concentrations and after the cell washing to remove the drug. In a concentration of 1 microgram/ml norfloxacin stimulated the zymosan-induced chemiluminescence. When the drug was used in a concentration of 10 micrograms/ml, the stimulating effect was less pronounced. In a concentration of 100 mu/ml norfloxacin significantly inhibited the leukocyte chemiluminescence. In concentrations of 0.1 to 100 micrograms/ml norfloxacin had no effect on the leukocyte adherence to the plastic surface covered by albumin.

  2. Microwave Assisted Synthesis, Characterisation and Fluorescence Studies of some Transition Metal Complexes with a Luminol Derivative.

    PubMed

    Aswathy, R; Mohanan, K

    2017-03-07

    A novel heterocyclic luminol derivative was synthesized by coupling diazotized 5-aminophthalhydrazide with 2-naphthol. This compound viz., Phthalhydrazide-5-azo-2-naphthol is versatile in forming stable metal complexes with cobalt(II), nickel(II), copper(II) and zinc(II) ions under microwave assisted solvent free conditions. The ligand and the metal complexes were characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, UV-Visible, IR, (1)H NMR, and ESR spectral studies wherever possible and applicable. The fluorescence spectra of the ligand and its metal complexes were also recorded. The fluorescence life time measurements were conducted and it was observed that binding of the ligand to the metal ion decreases the average life time of the metal complexes.

  3. Determination of photoirradiated high polar benzoylureas in tomato by HPLC with luminol chemiluminescence detection.

    PubMed

    Galera, M Martínez; García, M D Gil; Valverde, R Santiago

    2008-08-15

    This study reports the first analytical application of luminol chemiluminescence reaction for the sensitive detection of two benzoylurea insecticides (diflubenzuron and triflumuron). Off-line experiments demonstrated that previously irradiated traces of these benzoylurea insecticides largely enhanced the chemiluminescence emission yielded from the oxidation of luminol in methanol:water mixtures, by potassium permanganate in alkaline medium, the enhancement being proportional to the concentration of both pesticides. The two benzoylureas were determined in tomato samples by coupling liquid chromatography with post-column photoderivatization and detection based on this chemiluminescence reaction. Tomato samples were extracted using the QuEChERS method based on extraction with acetonitrile and dispersive solid-phase clean-up using primary and secondary amine (PSA). Interferences due to matrix effect were overcome by using matrix-matched standards. The optimised method was validated with respect to linearity, limits of detection and quantification, precision and accuracy. Under the optimised conditions, calibrations graphs were linear between 0.05 and 0.50 microg mL(-1) for diflubenzuron and between 0.10 and 1.00 microg mL(-1) for triflumuron. Method detection limits were 0.0025 and 0.0131 microg mL(-1) (equivalent to 0.0005 and 0.0026 mg kg(-1)) and quantification limits were 0.05 and 0.10 microg mL(-1) (equivalent to 0.01 and 0.02 mg kg(-1)) for diflubenzuron and triflumuron, respectively. In both cases, quantification limits were lower than the maximum residue levels (MRLs) established by the European legislation. The relative standard deviation of intra-day precision was below 10% and recoveries were between 79.7% and 94.2% for both pesticides.

  4. Fluorescence and electrochemiluminescence of luminol-reduced gold nanoparticles: photostability and platform effect.

    PubMed

    Wang, Wei; Xiong, Tao; Cui, Hua

    2008-03-18

    Water-soluble gold nanoparticles (AuNPs) capped with both fluorescent (FL) 3-aminophthalate (APA) and electrochemiluminescent (ECL) luminol molecules were described in our previous work. The synthetic and characteristic efforts of these functionalized AuNPs (lumAuNPs) were subsequently followed by investigations of their FL and ECL properties, as reported in the present work. It was observed that the FL intensity of a single gold nanoparticle was 70 times brighter than that of one free APA molecule, even though 91% of the FL emission of APA molecules on the surfaces of AuNPs was inhibited by gold cores through both intra- and interparticle quenching effects. Moreover, the photobleaching of surface-bound APA molecules was found to be dramatically inhibited compared with that of free ones in carbonate buffer. The improvement of photostability was attributed to the reactive AuNPs which acted as radical scavengers to protect the surface-bound APA molecules from oxidation by carbonate radicals. Furthermore, as-prepared lumAuNPs could react with cysteine to produce strong electrochemiluminescence, which was enhanced by 20-fold compared with that in the absence of cysteine. The experimental results suggested that luminol and cysteine were coadsorbed on the gold nanoparticle platform via Au-N and Au-S interactions, respectively. The shorter distance between reactant molecules by overcoming the electrostatic repulsion, that is, platform effect, was proposed to be responsible for the ECL enhancement. Combined with the biocompatibility of gold cores, the brighter FL emission, enhanced photostability, and stronger ECL intensity may make as-prepared lumAuNPs promising FL and ECL biomarkers for their applications in biosensors and bioimaging.

  5. Electrogenerated chemiluminescence resonance energy transfer between luminol and CdSe@ZnS quantum dots and its sensing application in the determination of thrombin.

    PubMed

    Dong, Yong-Ping; Gao, Ting-Ting; Zhou, Ying; Zhu, Jun-Jie

    2014-11-18

    In this work, electrogenerated chemiluminescence resonance energy transfer (ECL-RET) between luminol as a donor and CdSe@ZnS quantum dots (QDs) as an acceptor was reported in neutral conditions. It was observed that a glassy carbon electrode modified with CdSe@ZnS quantum dots (CdSe@ZnS/GCE) can catalyze the luminol oxidation to promote the anodic luminol ECL without coreactants. The intensity of anodic luminol ECL (0.60 V) at the CdSe@ZnS/GCE was enhanced more than 1 order of magnitude compared with that at the bare GCE. Another stronger anodic ECL peak observed at more positive potential (1.10 V) could be assigned to the ECL-RET between the excited state of luminol and the QDs. A label-free ECL aptasensor for the detection of thrombin was fabricated based on the synergic effect of the electrocatalysis and the ECL-RET. The approach showed high sensitivity, good selectivity, and wide linearity for the detection of thrombin in the range of 10 fM-100 pM with a detection limit of 1.4 fM (S/N = 3). The results suggested that the as-proposed luminol-QDs ECL biosensor will be promising in the detection of protein.

  6. Analysis of Monosodium l-Glutamate in Food Products by High-Performance Thin Layer Chromatography.

    PubMed

    Krishna, Veni N; Karthika, D; Surya, Devi M; Rubini, Mf; Vishalini, M; Pradeepa, Yj

    2010-07-01

    A simple, fast, specific, and precise high-performance thin layer chromatography method has been developed for the estimation of monosodium l-glutamate (MSG) in food products. Aluminum plates precoated with silica gel 60 GF(254)were used as stationary phase and a mixture of methanol-chloroform-formic acid in the ratio 5:5:1 (v/v) as mobile phase. Quantification was carried out by postchromatographic derivatization using 1% ninhydrin solution, and the developed spots were scanned by using a densitometer in absorbance mode at 485 nM. The R(f)value of MSG was 0.64. The results of the analysis have been validated statistically and by the recovery studies. Linearity was observed in the concentration range of 400-1000 nG.

  7. Strontium and Actinide Separations from High Level Nuclear Waste Solutions using Monosodium Titanate - Actual Waste Testing

    SciTech Connect

    Peters, T.B.; Barnes, M.J.; Hobbs,D.T.; Walker, D.D.; Fondeur, F.F.; Norato, M.A.; Pulmano, R.L.; Fink, S.D.

    2005-11-01

    Pretreatment processes at the Savannah River Site will separate {sup 90}Sr, alpha-emitting and radionuclides (i.e., actinides) and {sup 137}Cs prior to disposal of the high-level nuclear waste. Separation of {sup 90}Sr and alpha-emitting radionuclides occurs by ion exchange/adsorption using an inorganic material, monosodium titanate (MST). Previously reported testing with simulants indicates that the MST exhibits high selectivity for strontium and actinides in high ionic strength and strongly alkaline salt solutions. This paper provides a summary of data acquired to measure the performance of MST to remove strontium and actinides from actual waste solutions. These tests evaluated the effects of ionic strength, mixing, elevated alpha activities, and multiple contacts of the waste with MST. Tests also provided confirmation that MST performs well at much larger laboratory scales (300-700 times larger) and exhibits little affinity for desorption of strontium and plutonium during washing.

  8. Effect of systemic monosodium glutamate (MSG) on headache and pericranial muscle sensitivity.

    PubMed

    Baad-Hansen, L; Cairns, Be; Ernberg, M; Svensson, P

    2010-01-01

    We conducted a double-blinded, placebo-controlled, crossover study to investigate the occurrence of adverse effects such as headache as well as pain and mechanical sensitivity in pericranial muscles after oral administration of monosodium glutamate (MSG). In three sessions, 14 healthy men drank sugar-free soda that contained either MSG (75 or 150 mg/kg) or NaCl (24 mg/kg, placebo). Plasma glutamate level, pain, pressure pain thresholds and tolerance levels, blood pressure (BP), heart rate and reported adverse effects were assessed for 2 h. No muscle pain or robust changes in mechanical sensitivity were detected, but there was a significant increase in reports of headache and subjectively reported pericranial muscle tenderness after MSG. Systolic BP was elevated in the high MSG session compared with low MSG and placebo. These findings add new information to the concept of MSG headache and craniofacial pain sensitivity.

  9. Mixotrophic growth and biochemical analysis of Chlorella vulgaris cultivated with diluted monosodium glutamate wastewater.

    PubMed

    Ji, Yan; Hu, Wenrong; Li, Xiuqing; Ma, Guixia; Song, Mingming; Pei, Haiyan

    2014-01-01

    Monosodium glutamate wastewater (MSGW) is a potential medium for microbial cultivation because of containing abundant organic nutrient. This paper seeks to evaluate the feasibility of growing Chlorella vulgaris with MSGW and assess the influence of MSGW concentration on the biomass productivity and biochemical compositions. The MSGW diluted in different concentrations was prepared for microalga cultivation. C. vulgaris growth was greatly promoted with MSGW compared with the inorganic BG11 medium. C. vulgaris obtained the maximum biomass concentration (1.02 g/L) and biomass productivity (61.47 mg/Ld) with 100-time diluted MSGW. The harvested biomass was rich in protein (36.01-50.64%) and low in lipid (13.47-25.4%) and carbohydrate (8.94-20.1%). The protein nutritional quality and unsaturated fatty acids content of algal increased significantly with diluted MSGW. These results indicated that the MSGW is a feasible alternative for mass cultivation of C. vulgaris.

  10. Lactobacillus brevis G101 inhibits the absorption of monosodium glutamate in mice.

    PubMed

    Jang, Se-Eun; Han, Myung Joo; Kim, Se-Young; Kim, Dong-Hyun

    2014-11-28

    To evaluate the effect of Lactobacillus brevis G-101 on absorption of monosodium glutamate (MSG), we orally administered MSG with or without G-101 in mice and measured the maximum concentration (Cmax) and blood concentration curve (AUC) of MSG and γ- aminobutyric acid (GABA). Oral administration of G-101 (1 × 10(9) CFU/mouse) potently inhibited Cmax and AUC of MSG by 97.8% and 94.3%, respectively (p < 0.05), but increased those of GABA by 32.1% and 67.7%, respectively (p < 0.05). G-101 inhibited the absorption of MSG. These results suggest that G-101 may reduce the side effect of MSG by inhibiting the absorption of MSG.

  11. CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS

    SciTech Connect

    Hobbs, D.; Taylor-Pashow, K.; Missimer, D.

    2010-12-21

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. An inorganic sorbent, monosodium titanate (MST), is currently used to remove {sup 90}Sr and alpha-emitting radionuclides, while a caustic-side solvent extraction process is used for removing {sup 134,137}Cs. A new peroxotitanate material, modified MST, or mMST, has recently been developed and has shown increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the current baseline material, MST. This paper describes recent results focused on further characterization of this material.

  12. Chronic effects of arsenic on American red crayfish, Procambarus clarkii, exposed to monosodium methanearsonate (MSMA) herbicide

    SciTech Connect

    Naqvi, S.M. ); Flagge, C.T. )

    1990-07-01

    Bioaccumulative and biomagnifying effects of arsenic on crayfish have been reported. However, no work has been done on the chronic effects of this heavy metal on crayfish populations. There is a great concern for MSMA (Monosodium Methanearsonate) herbicide in the vicinity of natural waters due to its high water solubility and bioaccumulative potential. American red crayfish (Procambarus clarkii) account for 98% of the annual crayfish harvest in North America. Those pesticides which have greater water solubility (i.e. MSMA) than other less soluble compounds may cause higher mortalities of aquatic organisms, or cause adverse chronic effects if the non-target animals are sublethally exposed. This work was conducted in the laboratory to assess the possible chronic effects of arsenic on crayfish.

  13. Inhibition of monosodium urate crystal-induced inflammation by scopoletin and underlying mechanisms.

    PubMed

    Yao, Xiujuan; Ding, Zuoqi; Xia, Yufeng; Wei, Zhifeng; Luo, Yubin; Feleder, Carlos; Dai, Yue

    2012-12-01

    The present study determined the anti-inflammatory activity of scopoletin in gout air pouch model and revealed the underlying mechanisms by in vitro assays. Monosodium urate (MSU) crystal-induced inflammation in mouse air pouch model, an experimental model for acute gout, was used to assess the efficacy of scopoletin. The neutrophil and mononuclear phagocyte numbers and MPO levels were increased significantly six hours after MSU crystal injection into the air pouch, whereas these changes were inhibited substantially upon scopoletin (100 and 200mg/kg, i.p.) treatment. To get insight into the underlying mechanisms, the in vitro studies were performed to investigate the effects of scopoletin on activation of macrophages and resultant production of inflammatory mediators. The secretions of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), prostaglandin E(2) (PGE(2)) and nitric oxide (NO) were elevated in MSU crystal-stimulated RAW 264.7 cells, and scopoletin (30-300 μM) suppressed the production of all mediators. Moreover, RT-PCR assay and western blot analysis indicated that scopoletin regulated the transcriptional level of these mediators via suppression of NF-κB activation and blockade of MAPK signal pathway. Thus, the results clearly indicated that scopoletin inhibited the monosodium urate crystal-induced inflammation both in vivo and in vitro. In combination with our previous findings that scopoletin shows hypouricemic, anti-angiogenesis and pro-apoptotic activities, this compound may be a potential agent for gout therapy and could serve as a structural base for developing new drugs. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Size-dependent active effect of cadmium telluride quantum dots on luminol-potassium periodate chemiluminescence system for levodopa detection.

    PubMed

    Wang, Jianbo; Cui, Lijuan; Han, Suqin; Hao, Fang

    2015-06-01

    It was found that cadmium telluride (CdTe) quantum dots (QDs) with different sizes can have a great sensitizing effect on chemiluminescence (CL) emission from luminol-potassium periodate (KIO4) system. Levodopa, a widely prescribed drug in the treatment of Parkinson's disease, could inhibit luminol-KIO4-CdTe QDs CL reaction in alkaline solution. The inhibited CL intensity was proportional to the concentration of levodopa in the range from 8.0 nM to 10.0 μM. The detection limit was 3.8 nM. This method has been successfully applied to determine levodopa in pharmaceutical preparation and human urine and plasma samples with recoveries of 94.1-105.4%. This was the first work for inhibition effect determination of levodopa using a QD-based CL method.

  15. A comprehensive experimental study of industrial, domestic and environmental interferences with the forensic luminol test for blood.

    PubMed

    Creamer, J I; Quickenden, T I; Apanah, M V; Kerr, K A; Robertson, P

    2003-01-01

    This paper presents the fi rst comprehensive and quantitative study of substances that interfere with the forensic luminol test for blood. Two hundred and fifty substances have been selected on the basis of modern lifestyles and of contiguity with crime scenes. The intensity of the chemiluminescence produced by each substance has been measured relative to that of haemoglobin and the peak wavelength shift has also been determined. The following is a short list of nine substances that produce chemiluminescence intensities comparable with that of haemoglobin: turnips, parsnips, horseradishes, commercial bleach (NaClO), copper metal, some furniture polishes, some enamel paints, and some interior fabrics in motor vehicles. Care needs to be taken when the luminol test for blood is used in the presence of these substances.

  16. [Determining the postmortem interval of bone samples: a comparison of luminol chemiluminescence, Hexagon OBTI test, and Combur test].

    PubMed

    Ebach, Sarah C; Ramsthaler, Frank; Birngruber, Christoph G; Verhoff, Marcel A

    2010-01-01

    In the experiment, 16 human bones with known postmortem interval (PMI) that had been buried in soil (0.2 to about 2000 years) were tested in a blind setup with two established methods for determining the PMI (UV fluorescence of the surface of a fresh cut and the luminol chemiluminescence) and with two methods applied for this purpose for the first time (Hexagon OBTI test and Combur test). The results underline the importance of the UV fluorescence and luminol tests in determining the PMI, especially with regard to the question whether the PMI is forensically relevant or not. The results for both new methods, the Combur test strips and the Hexagon OBTI test, which were originally developed for the detection of hemoglobin, were negative for all samples. It remains to be seen if the negative results for these two methods may be due to an inability of hemoglobin or its metabolites to dissolve in the Tris buffer solution used in the experiment.

  17. Forensic Luminol Blood Test for Preventing Cross-contamination in Dentistry: An Evaluation of a Dental School Clinic

    PubMed Central

    Bortoluzzi, Marcelo Carlos; Cadore, Peterson; Gallon, Andrea; Imanishi, Soraia Almeida Watanabe

    2014-01-01

    Background: More than 200 different diseases may be transmitted from exposure to blood in the dental setting. The aim of this study is to identify possible faults in the crosscontamination chain control in a dental school clinic searching for traces of blood in the clinical contact surfaces (CCS) through forensic luminol blood test. Methods: Traces of invisible blood where randomly searched in CCS of one dental school clinic. Results: Forty eight surfaces areas in the CCS were tested and the presence of invisible and remnant blood was identified in 28 (58.3%) items. Conclusions: We suggest that the luminol method is suitable for identifying contamination with invisible blood traces and this method may be a useful tool to prevent cross-contamination in the dental care setting. PMID:25400895

  18. [Luminol oxidation by hydrogen peroxide with chemiluminescent signal formation catalyzed by peroxygenase from the fungus Agrocybe aegerita V.Brig].

    PubMed

    Vdovenko, M M; Ulrich, R; Hofrichter, M; Sakharov, I Iu

    2010-01-01

    Conditions of luminol oxidation by hydrogen peroxide in the presence of peroxygenase from the mushroom Agrocybe aegerita V.Brig have been optimized. The pH value (8.8) at which fungal peroxygenase produces a maximum chemiluminescent signal has been shown to be similar to the pH optimum value of horseradish peroxidase. Luminescence intensity changed when the concentration of Tris buffer was varied; maximum intensity of chemiluminescence was observed in 40 mM solution. It has been shown that enhancer (p-iodophenol) addition to the substrate mixture containing A. aegerita peroxygenase exerted almost no influence on the intensity of the chemiluminescent signal, similarly to soybean, palm, and sweet potato peroxidases. Enzyme detection limit in the reaction of luminol oxidation by hydrogen peroxide was 0.8 pM. High stability combined with high sensitivity make this enzyme a promising analytical reagent.

  19. Luminol encapsulated liposome as a signal generator for the detection of specific antigen-antibody reactions and nucleotide hybridization.

    PubMed

    Rakthong, Pakavadee; Intaramat, Akarin; Ratanabanangkoon, Kavi

    2010-01-01

    Liposomes prepared with biotinylated phospholipids and luminol entrapped were shown to be of 187 nm in size, 59% of which were unilamellar and with 43% luminol trapping efficiency. Liposome prepared from biotinylated phospholipids with a longer hydrophilic PEG2000 spacer, but not with the shorter hydrophobic caproyl one, bound efficiently and specifically with immobilized streptavidin in a microplate assay. The interactions of dinitrophenol and tobramycin with their respective antibodies, and the hybridization of 20-mers oligonucleotides were studied using the liposome as a signal generator. These reactions were shown to be specific with limits of detection of 0.58 microM, 0.96 microM and 18 nM, respectively.

  20. Application of response surface methodology (RSM) to the optimization of a post-column luminol chemiluminescence analysis of silyl peroxides.

    PubMed

    Baj, Stefan; Słupska, Roksana; Krawczyk, Tomasz

    2013-01-15

    The possibility of the utilization of chemiluminescence post-column luminol oxidation (CL) in a HPLC system for silyl peroxides analysis has been investigated. The conditions of HPLC separation for 12 silyl peroxides, representing bissilyl and alkyl-silyl peroxides, as well as their potential impurities, were established. Optimal chemiluminescent post-column reaction conditions were found using central composite design (CCD) and response surface methodology (RSM). The interaction effects of four of the most important operating variables - the concentrations of luminol, hemin, sodium hydroxide and the post-column solution flow rate - on the light intensity were evaluated. The optimized conditions for analysis were the same for bissilyl and alkyl-silyl peroxides for the base concentration (0.03 M), the luminol concentration (0.4 g L(-1)) and the hemin concentration (0.3 g L(-1)). The only differences occurred in a reagent flow rate (for bissilyl peroxide -0.3 mL min(-1) and for alkyl-silyl peroxides -0.9 mL min(-1)). Under optimal conditions, the detection limits were in the 0.07-0.16 nM range for bissilyl, and 0.53-1.01 for alkyl-silyl peroxides. The calibration curves were linear in the 0.25-3 nM range for bissilyl and the 2.5-25 range for alkyl-silyl peroxides. Intra-day and inter-day precision was lower than 5.5% for each tested concentration level. A mechanism of luminol oxidation by silyl peroxides involving a hydrolysis step with the formation of hydrogen peroxide or hydroperoxide was proposed.

  1. Effects of non-steroidal anti-inflammatory drugs on the luminol and lucigenin amplified chemiluminescence of human neutrophils.

    PubMed

    Parij, N; Nagy, A M; Fondu, P; Nève, J

    1998-07-10

    A panel of non-steroidal anti-inflammatory drugs commonly used for therapeutic purposes was assessed for their effects on the respiratory burst of isolated human polymorphonuclear neutrophils. Cells were stimulated with opsonised yeast and the production of reactive oxygen species was measured by amplified chemiluminescence with luminol and lucigenin which are two luminogenic agents measuring different cellular events. A special attention was devoted to the establishment of dose-effect curves and calculation of ED50. Some of the drugs tested (acemetacine, diclofenac, flufenamic acid and niflumic acid) were able to decrease both luminol and lucigenin chemiluminescence in a dose-dependent manner reflecting an inhibitory effect on the respiratory burst. The most potent derivative was flufenamic acid (ED50 8 and 78 microM, respectively, with luminol and lucigenin), followed by diclofenac (21 and 98 microM), niflumic acid (97 and 227 microM) and acemetacine (585 and 427 microM). In contrast, several other drugs (flurbiprofen, ibuprofen, ketoprofen, piroxicam) stimulated both luminol and lucigenin chemiluminescence, suggesting a pro-oxidant activity. Acetylsalicylic acid (up to 1250 microM) was a modest inhibitor (maximum 25% inhibition) showing no dose-dependent effect and tolmetin (up to 125 microM) had no significant effect in both systems. The results were in agreement using both luminogenic agents, except for indomethacin, naproxen and tenoxicam which showed different kinds of effects. The unspecific and complex nature of the measurement systems used did not allow to give a complete mechanistic interpretation of the results, but the comparison with literature data gave some pertinent explanations for both anti- and pro-oxidant effects.

  2. Chemiluminescence microfluidic system of gold nanoparticles enhanced luminol-silver nitrate for the determination of vitamin B12.

    PubMed

    Kamruzzaman, Mohammad; Alam, Al-Mahmnur; Kim, Kyung Min; Lee, Sang Hak; Kim, Young Ho; Kabir, A N M Hamidul; Kim, Gyu-Man; Dang, Trung Dung

    2013-02-01

    A rapid and sensitive chemiluminescence (CL) system coupled with a microfluidic chip has been presented to determine vitamin B12 (VB12) based on the reaction of luminol and silver nitrate (AgNO(3)) in the presence of gold nanoparticles (AuNPs). A microfluidic chip was fabricated by a soft-lithographic procedure using polydimethyl siloxane (PDMS) having four inlets and one outlet with a 200 μm wide, 250 μm deep, and 100 mm long microchannel. Ag(+) was used as a chemiluminogenic oxidant in this CL reaction which oxidized luminol to produce strong CL signal in the presence of AuNPs. Luminol reacted with AgNO(3) under the catalysis of AuNPs to produce luminol radicals which reacted with dissolved oxygen and emitted CL light. The proposed CL system was applied to determine the amount of VB12 in VB12 tablets and multivitamin. Under the optimum conditions, the CL intensity of the system was increased with the concentration of VB12 in the range of 0.25-100 ng mL(-1) with the correlation coefficient of 0.9982. The limit of detection was found to be 0.04 ng mL(-1) with the relative standard deviation of 1.56 % for five replicate determinations of 25 ng mL(-1) of VB12. The CL reaction mechanism was demonstrated by UV-visible spectra and CL emission spectra.

  3. Combining complement fixation and luminol chemiluminescence for ultrasensitive detection of avian influenza A rH7N9.

    PubMed

    Li, Man; Shi, ZhuanZhuan; Li, ChangMing; Yu, Ling

    2016-03-21

    The complement fixation test (CFT) is a serological test that can be used to detect the presence of either a specific antibody or antigen to diagnose infections. In a conventional CFT, the assay result is determined by observing the clarity of the reaction solution or the sediment of red cells by the naked eye. Although the assay conditions are thereafter simplified, the sensitivity of the assay would be sacrificed due to the limitation of bulk observation. Inspired by the forensic scientists to examine blood at the scene of the crime, we rationally argued that the luminol chemiluminescence (CL) reaction could be applied in the CFT to sense physiological complement-mediated haemolytic phenomena for sensitive protein detection. The combination of the CFT and the luminol CL system was demonstrated in detection of rH7N9, a recombinant avian influenza virus protein. The testing can be accomplished within 2.5 h and the linear detection range covers 0.25 fg mL(-1) to 25 ng mL(-1). The feasibility of the CL based CFT in assaying a real biopsy was successfully demonstrated by specifically detecting rH7N9 and the carcinoembryonic antigen (CEA) in human serum. This new type of protein detection approach inherits the beauty of complement-mediated assay, such as being fast, and no protein immobilization, blocking and washing. In addition, the participation of luminol CL enables us to quantitatively analyse the intensity of a haemeolysis process, ameliorating the limitation of bulk observation in traditional CFT. It is anticipated that the luminol CL-CFT assay would be particularly suitable for investigation of small molecules, toxins, and short peptides.

  4. Technical note: The effects of Bluestar(®) and luminol when used in conjunction with tetramethylbenzidine or phenolphthalein.

    PubMed

    Luedeke, Makayla; Miller, Emily; Sprague, Jon E

    2016-05-01

    There are numerous presumptive tests available in the forensic science field to help identify the presence of blood. While many articles are available on the effects of Bluestar(®) and luminol and potential interactions with subsequent DNA identification, the research field falls short in identifying the effects these two presumptive tests may have on subsequent presumptive tests used to help identify blood. To rectify this ongoing issue in the forensic science field, the chemiluminescence methods of Bluestar(®) and luminol for the detection of blood at a crime scene were tested for their effects when used in conjunction with tetramethylbenzidine (TMB) or phenolphthalein (PT) at the forensic science laboratory. Six different substrates (untreated wood, pressure treated wood, ceramic tile, shag carpet, cement block, and cotton clothing) were stained with varying dilutions (range 1:1 to 1:100,000) of blood. Neither luminol nor Bluestar(®) affect the results of PT or TMB tests at blood dilutions equal to or less than 1:100. However, interactions did occur between agents and substrates with blood dilutions 1:1000 or greater. Bluestar(®) was the only presumptive test that can detect blood dilutions of 1:100,000 on some substrates and luminol was inclusive on pressure treated wood. These findings suggests that forensic science laboratory personal need to know and understand the details of how the blood was detected by the crime scene investigator and the substrate on which the blood was obtained from for their preparation of presumptive blood testing with PT or TMB. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. [Human serum albumin modified under oxidative/halogenative stress enhances luminol-dependent chemiluminescence of human neutrophils].

    PubMed

    Mikhal'chik, E V; Smolina, N V; Astamirova, T C; Gorudko, I V; Grigor'eva, D V; Ivanov, V A; Sokolov, A V; Kostevich, V A; Cherenkevich, S N; Panasenko, O M

    2013-01-01

    It is shown that human serum albumin, previously treated with HOCl (HSA-Cl), enhances luminol-dependent chemiluminescence of neutrophils activated by phorbol-12-myristate-13-acetate (PMA). The enzyme-linked immunosorbent assay revealed that addition of HSA-Cl to neutrophils promotes exocytosis of myeloperoxidase. Inhibitor of myeloperoxidase--4-aminobenzoic acid hydrazide, without any effect on lucigenin-dependent chemiluminescence of neutrophils stimulated with PMA, effectively suppressed luminol-dependent chemiluminescence (IC50 = 20 microM) under the same conditions. The transfer of the cells from medium with HSA-Cl and myeloperoxidase to fresh medium abolished an increase in PMA-induced luminol-dependent chemiluminescence, but not the ability of neutrophils to respond to re-addition of HSA-Cl. A direct and significant (r = 0.75, p) correlation was observed between the intensity of PMA stimulated neutrophil chemiluminescence response and myeloperoxidase activity in the cell-free media after chemiluminescence measurements. These results suggest the involvement of myeloperoxidase in the increase of neutrophil PMA-stimulated chemiluminescence response in the presence of HSA-Cl. A significant positive correlation was found between myeloperoxidase activity in blood plasma of children with severe burns and the enhancing effects of albumin fraction of the same plasma on luminol-dependent chemiluminescence of PMA-stimulated donor neutrophils. These results support a hypothesis that proteins modified in reactions involving myeloperoxidase under oxidative/halogenative stress, stimulate neutrophils, leading to exocytosis of myeloperoxidase, a key element of halogenative stress, and to closing a "vicious circle" of neutrophil activation at the inflammatory site.

  6. Positive potential operation of a cathodic electrogenerated chemiluminescence immunosensor based on luminol and graphene for cancer biomarker detection.

    PubMed

    Xu, Shoujiang; Liu, Yang; Wang, Taihong; Li, Jinghong

    2011-05-15

    In this work, we report a cathodic electrogenerated chemiluminescence (ECL) of luminol at a positive potential (ca. 0.05 V vs Ag/AgCl) with a strong light emission on the graphene-modified glass carbon electrode. The resulted graphene-modified electrode offers an excellent platform for high-performance biosensing applications. On the basis of the cathodic ECL signal of luminol on the graphene-modified electrode, an ECL sandwich immunosensor for sensitive detection of cancer biomarkers at low potential was developed with a multiple signal amplification strategy from functionalized graphene and gold nanorods multilabeled with glucose oxidase (GOx) and secondary antibody (Ab(2)). The functionalized graphene improved the electron transfer on the electrode interface and was employed to attach the primary antibody (Ab(1)) due to it large surface area. The gold nanorods were not only used as carriers of secondary antibody (Ab(2)) and GOx but also catalyzed the ECL reaction of luminol, which further amplified the ECL signal of luminol in the presence of glucose and oxygen. The as-proposed low-potential ECL immunosensor exhibited high sensitivity and specificity on the detection of prostate protein antigen (PSA), a biomarker of prostate cancer that was used as a model. A linear relationship between ECL signals and the concentrations of PSA was obtained in the range from 10 pg mL(-1) to 8 ng mL(-1). The detection limit of PSA was 8 pg mL(-1) (signal-to-noise ratio of 3). Moreover, the as-proposed low-potential ECL immunosensor exhibited excellent stability and reproducibility. The graphene-based ECL immunosensor accurately detected PSA concentration in 10 human serum samples from patients demonstrated by excellent correlations with standard chemiluminescence immunoassay. The results suggest that the as-proposed graphene ECL immunosensor will be promising in the point-of-care diagnostics application of clinical screening of cancer biomarkers.

  7. Investigation of Luminol and Collection Tape Components and the Effects of Airborne Interferents on the XM19 Detector

    DTIC Science & Technology

    1975-01-31

    ABSTRACT Additional studies on the stability of solid oxidants showed that sodium perborate monohydrate (NaBO3 -H2 0) can be satisfacto...if the packet is made of a water- impermeable material. Neither sodium perborate tetrahydrate (NaBO3.4H 20) nor sudium pyrophosphate peroxyhydrate...Sec’nd Quarterly 4.eport, studies were conducted concerning the storage of solid oxidants and the use of a luminol- perborate premix; also

  8. Luminol functionalized gold nanoparticles as colorimetric and chemiluminescent probes for visual, label free, highly sensitive and selective detection of minocycline

    NASA Astrophysics Data System (ADS)

    He, Yi; Peng, Rufang

    2014-11-01

    In this work, luminol functionalized gold nanoparticles (LuAuNPs) were used as colorimetric and chemiluminescent probes for visual, label free, sensitive and selective detection of minocycline (MC). The LuAuNPs were prepared by simple one-pot reduction of HAuCl4 with luminol, which exhibited a good chemiluminescence (CL) activity owing to the presence of luminol molecules on their surface and surface plasmon resonance absorption. In the absence of MC, the color of LuAuNPs was wine red and their size was relatively small (˜25 nm), which could react with silver nitrate, producing a strong CL emission. Upon the addition of MC at acidic buffer solutions, the electrostatic interaction between positively charged MC and negatively charged LuAuNPs caused the aggregation of LuAuNPs, generating a purple or blue color. Simultaneously, the aggregated LuAuNPs did not effectively react with silver nitrate, producing a weak CL emission. The signal change was linearly dependent on the logarithm of MC concentration in the range from 30 ng to 1.0 μg for colorimetric detection and from 10 ng to 1.0 μg for CL detection. With colorimetry, a detection limit of 22 ng was achieved, while the detection limit for CL detection modality was 9.7 ng.

  9. Intensification of the electrochemiluminescence of luminol on hollow TiO₂ nanoshell-modified indium tin oxide electrodes.

    PubMed

    Hong, Jia; Ming, Liang; Tu, Yifeng

    2014-10-01

    Hollow titania nanoshells (HTNSs), which were synthesized by a SiO2 sacrificial template method, were used to intensify the electrochemiluminescence (ECL) of luminol. The size, shell thickness and crystal phase, factors that are important in determining the efficiency, can be controlled by adjusting the template size, precursor concentration and calcination temperature, respectively. The structure of the HTNSs was characterized by transmission electron microscopy, scanning electron microscopy and X-ray diffraction spectroscopy. After structural optimization, the surface of indium tin oxide (ITO)-coated glass was modified with the HTNSs to act as a working electrode for a flow-injection analytical system. The heterostructure demonstrated an ECL emission intensity 150 times higher than that of the bare ITO. The research also revealed that the ECL of luminol on this modified electrode showed a very sensitive response to hydrogen peroxide with a detection limit of 4.6×10(-10)M. In addition to discussing the intensifying mechanism of luminol ECL by HTNSs, we demonstrate that can be successfully applied to evaluate the gross antioxidant activity of garlic. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Long-lasting chemiluminescence of luminol on electrochemically pre-oxidized platinum electrodes in NaOH solution.

    PubMed

    Lin, X Q; Sun, Y G; Cui, H

    2000-01-01

    A long-lasting bright chemiluminescence (CL) of luminol was generated at polycrystalline platinum electrodes with open circuit. The CL can last for several hours with the presence of O(2) in the solution when the electrode was preoxidized at potentials more positive than 1.10 V vs. SCE. The effects of the varieties of solution conditions and surface states of the electrode on the CL intensity and the interfacial potential of the electrode were investigated. It was proposed that PtO was generated at the pre-oxidized potentials and played a role of catalyst of luminol oxidation for generating the CL. The redox couple of PtO/Pt(active) at the electrode surface was maintained in the presence of O(2) and luminol, and generated the interfacial potential more positive than 140 mV. Mathematical treatment of the reaction mechanism was conducted, which led to an approximated expression of a steady CL intensity (I(CL)) as a function of the pre-polarization potential (E( h)) and time (tau( h)) of the electrode. An empirical equation, (I(CL))(4/3) = 3480(-1 + 0.82E( h) + 0.037 ln tau( h)), was estimated from the experimental data. Copyright 2000 John Wiley & Sons, Ltd.

  11. Sensitive assay of hexythiazox residue in citrus fruits using gold nanoparticles-catalysed luminol-H2O2 chemiluminescence.

    PubMed

    Khajvand, Tahereh; Chaichi, Mohammad Javad; Colagar, Abasalt Hosseinzadeh

    2015-04-15

    A new sensitive chemiluminescence (CL) procedure for the detection of hexythiazox (HXTZ) is presented, based on the quenching effect of the HXTZ in the luminol-H2O2 system using gold nanoparticles (GNPs) as a catalyst. The Box-Behnken design matrix and response surface methodology (RSM) have been applied in designing the experiments for studying the interactive effects of the three most important variables pH, luminol, and H2O2 concentrations on the CL intensity of luminol catalysed by GNPs. Under the optimal conditions, the CL intensity was linear with HXTZ concentration in the range of 0.017-0.42 μg mL(-1), and the limit of detection (LoD) was 0.011 μg mL(-1). The procedure has been successfully applied to the detection of HXTZ residues in citrus fruits and water samples at trace levels. Mean recoveries obtained were between 84.0% and 95.3%, with a repeatability precision of <6%. Meanwhile, the possible mechanism of the inhibited CL intensity was discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. A novel luminol chemiluminescent method catalyzed by silver/gold alloy nanoparticles for determination of anticancer drug flutamide

    NASA Astrophysics Data System (ADS)

    Chaichi, Mohammad Javad; Azizi, Seyed Naser; Heidarpour, Maryam

    2013-12-01

    It was found that silver/gold alloy nanoparticles enhance the chemiluminescence (CL) of the luminol-H2O2 system in alkaline solution. The studies of UV-Vis spectra, CL spectra, effects of concentrations luminol, hydrogen peroxide and silver/gold alloy nanoparticles solutions were carried out to explore the CL enhancement mechanism. Flutamide was found to quench the CL signals of the luminol-H2O2 reaction catalyzed by silver/gold alloy nanoparticles, which made it applicable for the determination of flutamide. Under the optimum conditions, the CL intensity is proportional to the concentration of the flutamide in solution over the range 5.0 × 10-7 to 1.0 × 10-4 mol L-1. Detection limit was obtained 1.2 × 10-8 mol L-1and the relative standard deviation (RSD) γ5%. This work is introduced as a new method for the determination of flutamide in commercial tablets. Box-Behnken experimental design is applied to investigate and validate the CL measurement parameters.

  13. Luminol functionalized gold nanoparticles as colorimetric and chemiluminescent probes for visual, label free, highly sensitive and selective detection of minocycline.

    PubMed

    He, Yi; Peng, Rufang

    2014-11-14

    In this work, luminol functionalized gold nanoparticles (LuAuNPs) were used as colorimetric and chemiluminescent probes for visual, label free, sensitive and selective detection of minocycline (MC). The LuAuNPs were prepared by simple one-pot reduction of HAuCl₄ with luminol, which exhibited a good chemiluminescence (CL) activity owing to the presence of luminol molecules on their surface and surface plasmon resonance absorption. In the absence of MC, the color of LuAuNPs was wine red and their size was relatively small (∼25 nm), which could react with silver nitrate, producing a strong CL emission. Upon the addition of MC at acidic buffer solutions, the electrostatic interaction between positively charged MC and negatively charged LuAuNPs caused the aggregation of LuAuNPs, generating a purple or blue color. Simultaneously, the aggregated LuAuNPs did not effectively react with silver nitrate, producing a weak CL emission. The signal change was linearly dependent on the logarithm of MC concentration in the range from 30 ng to 1.0 μg for colorimetric detection and from 10 ng to 1.0 μg for CL detection. With colorimetry, a detection limit of 22 ng was achieved, while the detection limit for CL detection modality was 9.7 ng.

  14. A novel luminol chemiluminescent method catalyzed by silver/gold alloy nanoparticles for determination of anticancer drug flutamide.

    PubMed

    Chaichi, Mohammad Javad; Azizi, Seyed Naser; Heidarpour, Maryam

    2013-12-01

    It was found that silver/gold alloy nanoparticles enhance the chemiluminescence (CL) of the luminol-H2O2 system in alkaline solution. The studies of UV-Vis spectra, CL spectra, effects of concentrations luminol, hydrogen peroxide and silver/gold alloy nanoparticles solutions were carried out to explore the CL enhancement mechanism. Flutamide was found to quench the CL signals of the luminol-H2O2 reaction catalyzed by silver/gold alloy nanoparticles, which made it applicable for the determination of flutamide. Under the optimum conditions, the CL intensity is proportional to the concentration of the flutamide in solution over the range 5.0 × 10(-7) to 1.0 × 10(-4)mol L(-1). Detection limit was obtained 1.2 × 10(-8)mol L(-1)and the relative standard deviation (RSD) γ5%. This work is introduced as a new method for the determination of flutamide in commercial tablets. Box-Behnken experimental design is applied to investigate and validate the CL measurement parameters. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Evaluation of the catalytic decomposition of H2O2 through use of organo-metallic complexes--a potential link to the luminol presumptive blood test.

    PubMed

    Soderquist, Thomas J; Chesniak, Olivia M; Witt, Matthew R; Paramo, Alan; Keeling, Victoria A; Keleher, Jason J

    2012-06-10

    Forensic scientists use several presumptive tests to detect latent blood stains at crime scenes; one of the most recognizable being the luminol reagent. Luminol, under basic conditions, reacts with an oxidizing species which, with the help of a transition metal catalyst facilitates a luminescent response. The typical oxidizing species used in the luminol reaction is hydrogen peroxide (H(2)O(2)). While the luminol reaction has been studied since its inception, the mechanistic pathway is still an area of great debate. Previous work suggests that the luminol reaction with latent blood stains possesses a correlation to the Fenton-Decomposition reaction mechanism, which decomposes H(2)O(2) into the strongly oxidizing hydroxyl radical (*OH) species. This work seeks to understand the luminol reaction on a mechanistic level and to determine if a synergy exists between the chemiluminescence observed in the reaction and the production of the hydroxyl radical via Fenton-like processes. Results indicate that organo-metallic complexes produce hydroxyl radicals at different rates and different concentrations. These findings appear to be related to structural differences in the organo-metallic complex, which conform to the 18 electron rule or are one electron rich/deficient. Furthermore, the production of *OH is controlled by the chemical environment which governs complex stability at high pH conditions, reflective of the luminol process. Model hemoglobin systems reveal a strong correlation between the rate of *OH production via the Fenton-like pathway and maximum chemiluminescent intensity. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. AgBr nanoparticles/3D nitrogen-doped graphene hydrogel for fabricating all-solid-state luminol-electrochemiluminescence Escherichia coli aptasensors.

    PubMed

    Hao, Nan; Zhang, Xuan; Zhou, Zhou; Hua, Rong; Zhang, Ying; Liu, Qian; Qian, Jing; Li, Henan; Wang, Kun

    2017-11-15

    It is necessary to develop rapid, simple and accurate detection method for Escherichia coli (E. coli) due to its widely distributed pathogenic bacteria. Herein, we prepared AgBr nanoparticles (NPs) anchored 3D nitrogen-doped graphene hydrogel (3DNGH) nanocomposites with an exceptionally large accessible surface by a simple hydrothermal approach. The as-prepared 3DNGH porous nanocomposite not only showed better conductivity than that of 3D graphene due to introducing nitrogen element into graphene framework, but also provided a high loading volume for immobilizing luminol. Meanwhile the anchored AgBr NPs served as the catalyst can effectively enhance the ECL behavior of luminol. And the resulting luminol/AgBr/3DNGH exhibited more excellent ECL performances, which was about 2, 3, 8 times enhanced respectively, comparing to luminol/AgBr/3DGH, luminol/3DNGH and luminol/AgBr/2DNG. Further, the multifunctional nanoarchitecture was used as the all-solid-state ECL platform for fabricating Escherichia coli aptasensors via glutaraldehyde as crosslinking agent between amine-functionalized E. coli aptamer and luminol/AgBr/3DNGH. Based on the steric hindrance mechanism that E.coli can significantly decrease the ECL intensity, the proposed aptasensor displayed a linear response for E.coli in the range from 0.5 to 500 cfu/mL with an extremely low detection limit of 0.17 cfu/mL (S/N). In addition, this ECL aptasensor possessed great advantages including the simple operation process, low-cost and sensitivity, which provided a promising approach for the E.coli detection in biomedical, food detection and environmental analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. CdTe quantum dots@luminol as signal amplification system for chrysoidine with chemiluminescence-chitosan/graphene oxide-magnetite-molecularly imprinting sensor.

    PubMed

    Duan, Huimin; Li, Leilei; Wang, Xiaojiao; Wang, Yanhui; Li, Jianbo; Luo, Chuannan

    2016-01-15

    A sensitive chemiluminescence (CL) sensor based on chemiluminescence resonance energy transfer (CRET) in CdTe quantum dots@luminol (CdTe QDs@luminol) nanomaterials combined with chitosan/graphene oxide-magnetite-molecularly imprinted polymer (Cs/GM-MIP) for sensing chrysoidine was developed. CdTe QDs@luminol was designed to not only amplify the signal of CL but also reduce luminol consumption in the detection of chrysoidine. On the basis of the abundant hydroxy and amino, Cs and graphene oxide were introduced into the GM-MIP to improve the adsorption ability. The adsorption capacities of chrysoidine by both Cs/GM-MIP and non-imprinted polymer (Cs/GM-NIP) were investigated, and the CdTe QDs@luminol and Cs/GM-MIP were characterized by UV-vis, FTIR, SEM and TEM. The proposed sensor can detect chrysoidine within a linear range of 1.0×10(-7) - 1.0×10(-5) mol/L with a detection limit of 3.2×10(-8) mol/L (3δ) due to considerable chemiluminescence signal enhancement of the CdTe quantum dots@luminol detector and the high selectivity of the Cs/GM-MIP system. Under the optimal conditions of CL, the CdTe QDs@luminol-Cs/GM-MIP-CL sensor was used for chrysoidine determination in samples with satisfactory recoveries in the range of 90-107%. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Comparison of antioxidant activities of aminoguanidine, methylguanidine and guanidine by luminol-enhanced chemiluminescence

    PubMed Central

    Yildiz, Gülüzar; Demiryürek, A Tuncay; Sahin-Erdemli, Inci; Kanzik, Ilker

    1998-01-01

    The objective of this study was to investigate the ability of aminoguanidine, methylguanidine and guanidine to inhibit free radicals or metabolites generated by either stimulated human leucocytes or cell-free systems using luminol-enhanced chemiluminescence (CL).Aminoguanidine (0.1 μM–10 mM), methylguanidine (10 μM–10 mM) and guanidine (10 μM–10 mM) produced concentration-dependent inhibition (96±0.1%, n=7, 59±1.3%, n=6, and 62±3%, n=6, P<0.05 at 10 mM, respectively) in FMLP-stimulated leucocytes CL.In cell-free experiments, hydrogen peroxide (H2O2), hypochlorous acid (HOCl), hydroxyl radical and peroxynitrite-induced CL responses were initiated by hydrogen peroxide (3.5 mM), NaOCl (50 μM), FeSO4 (40 nM) and peroxynitrite (20 nM), respectively. Aminoguanidine, methylguanidine and guanidine produced concentration-dependent inhibition in H2O2-(69±0.7%, n=7, 26±1%, n=6, and 15±0.5%, n=6, at 1 mM, respectively) and HOCl-(84±0.3%, n=6, 50±1%, n=6, and 29±1%, n=7, at 1 mM, respectively) induced luminol CL. Peroxynitrite-induced CL was markedly attenuated in a concentration-dependent manner by aminoguanidine (99±0.1%, n=6, at 10 mM), methylguanidine (5±0.2%, n=6, at 10 mM) and guanidine (27±0.4%, n=7, at 10 mM). However, inhibition with aminoguanidine was found to be more marked than with methylguanidine and guanidine. Aminoguanidine (95±0.5%, n=6, at 1 mM) and methylguanidine (25±1%, n=6, at 1 mM), but not guanidine (2±1%, n=6, at 1 mM), significantly decreased ferrous iron-induced CL.Collectively, these data suggest that aminoguanidine and a high concentration (⩾0.1 mM) of methylguanidine have direct scavenging activities against H2O2, HOCl, hydroxyl radical and peroxynitrite. Guanidine, at a high concentration (⩾0.1 mM), scavenges H2O2, HOCl and peroxynitrite, but not the hydroxyl radical. These direct scavenging properties may contribute to inhibitory effects of these compounds on human leucocyte

  19. CoFe2O4 nanoparticles as oxidase mimic-mediated chemiluminescence of aqueous luminol for sulfite in white wines.

    PubMed

    Zhang, Xiaodan; He, Shaohui; Chen, Zhaohui; Huang, Yuming

    2013-01-30

    Recently, the intrinsic enzyme-like activity of nanoparticles (NPs) has become a growing area of interest. However, the analytical applications of the NP-based enzyme mimetic are mainly concentrated on their peroxidase-like activity; no attempts have been made to investigate the analytical applications based on the oxidase mimic activities of NPs. For the first time, we report that CoFe(2)O(4) NPs were found to possess intrinsic oxidase-like activity and could catalyze luminol oxidation by dissolved oxygen to produce intensified chemiluminescence (CL). The effect of sulfite on CoFe(2)O(4) NP oxidase mimic-mediated CL of aqueous luminol was investigated. It is very interesting that when adding sulfite to the luminol-CoFe(2)O(4) system, the role of sulfite in the luminol-CoFe(2)O(4) NP-sulfite system depends on its concentration. At a relatively low concentration level, sulfite presents an inhibition effect on the luminol-CoFe(2)O(4) NP system. However, it does have an enhancement effect at a higher concentration level. Investigations on the effect of the solution pH and luminol and CoFe(2)O(4) NP concentrations on the kinetic characteristics of the studied CL system in the presence of trace sulfite suggested that the enhancement and inhibition of the luminol-CoFe(2)O(4) NP-sulfite CL system also depended on the solution pH. It seems that the concentrations of luminol and CoFe(2)O(4) NPs did not influence the CL pathway. The possible mechanism of the luminol-CoFe(2)O(4) NP-sulfite CL system was also discussed. On this basis, a flow injection chemiluminescence method was established for the determination of trace sulfite in this study. Under the optimal conditions, the proposed system could respond down to 2.0 × 10(-8) M sulfite. The method has been applied to the determination of trace sulfite in white wine samples with satisfactory results. The results given by the proposed method are in good agreement with those given by the standard titration method.

  20. The efficacy of probiotics for monosodium glutamate-induced obesity: dietology concerns and opportunities for prevention

    PubMed Central

    2014-01-01

    Introduction Obesity becomes endemic today. Monosodium glutamate was proved as obesogenic food additive. Probiotics are discussed to impact on obesity development. Aims and objectives The aim was to study the effects of probiotics on the development of monosodium glutamate (MSG)-induced obesity in rats. Material and methods We included 45 Wistar male rats and divided into three groups (n = 15). Newborn rats of group 1 (control) received subcutaneously 8 μl/g saline. Group 2 received 3 to 4 mg/g MSG subcutaneously on the second, fourth, sixth, eighth and tenth day of life. Within 4 months after birth, rats were on a standard diet. Group 3 received an aqueous solution of probiotics mixture (2:1:1 Lactobacillus casei IMVB-7280, Bifidobacterium animalis VKL, B. animalis VKB) at the dose of 5 × 109 CFU/kg (50 mg/kg) intragastrically. Administration of probiotics was started at the age of 4 weeks just after weaning and continued for 3 months during 2-week courses. Group 2 received intragastrically 2.5 ml/kg water. Organometric and biochemical parameters in all groups of rats were analyzed over 4 months. The concentration of adiponectin was determined in serum, and leptin - in adipose tissue. Results Administration of MSG led to the development of obesity in rats; body weight had increased by 7.9% vs controls (p < 0.05); body length had increased by 5.4% (p < 0.05). Body mass index and Lee index and visceral fat mass had increased (p < 0.001). Under the neonatal injection of MSG, the concentration of total cholesterol, triglycerides, VLDL cholesterol and LDL cholesterol significantly increased (p < 0.001), in comparison with controls. Adipose-derived hormones changed in MSG obesity rats: adiponectin decreased by 58.8% (p < 0.01), and leptin concentration in adipose tissue had increased by 74.7% (p < 0.01). The probiotic therapy of rats from group 3 prevented obesity development. Parameters of rats treated with probiotic mixture did not differ from that in

  1. The efficacy of probiotics for monosodium glutamate-induced obesity: dietology concerns and opportunities for prevention.

    PubMed

    Savcheniuk, Oleksandr A; Virchenko, Oleksandr V; Falalyeyeva, Tetyana M; Beregova, Tetyana V; Babenko, Lidia P; Lazarenko, Liudmyla M; Demchenko, Olga M; Bubnov, Rostyslav V; Spivak, Mykola Ya

    2014-01-13

    Obesity becomes endemic today. Monosodium glutamate was proved as obesogenic food additive. Probiotics are discussed to impact on obesity development. The aim was to study the effects of probiotics on the development of monosodium glutamate (MSG)-induced obesity in rats. We included 45 Wistar male rats and divided into three groups (n = 15). Newborn rats of group 1 (control) received subcutaneously 8 μl/g saline. Group 2 received 3 to 4 mg/g MSG subcutaneously on the second, fourth, sixth, eighth and tenth day of life. Within 4 months after birth, rats were on a standard diet. Group 3 received an aqueous solution of probiotics mixture (2:1:1 Lactobacillus casei IMVB-7280, Bifidobacterium animalis VKL, B. animalis VKB) at the dose of 5 × 109 CFU/kg (50 mg/kg) intragastrically. Administration of probiotics was started at the age of 4 weeks just after weaning and continued for 3 months during 2-week courses. Group 2 received intragastrically 2.5 ml/kg water. Organometric and biochemical parameters in all groups of rats were analyzed over 4 months. The concentration of adiponectin was determined in serum, and leptin - in adipose tissue. Administration of MSG led to the development of obesity in rats; body weight had increased by 7.9% vs controls (p < 0.05); body length had increased by 5.4% (p < 0.05). Body mass index and Lee index and visceral fat mass had increased (p < 0.001). Under the neonatal injection of MSG, the concentration of total cholesterol, triglycerides, VLDL cholesterol and LDL cholesterol significantly increased (p < 0.001), in comparison with controls. Adipose-derived hormones changed in MSG obesity rats: adiponectin decreased by 58.8% (p < 0.01), and leptin concentration in adipose tissue had increased by 74.7% (p < 0.01). The probiotic therapy of rats from group 3 prevented obesity development. Parameters of rats treated with probiotic mixture did not differ from that in the control. The introduction of MSG to newborn rats caused the

  2. The comparative performance of PMI estimation in skeletal remains by three methods (C-14, luminol test and OHI): analysis of 20 cases.

    PubMed

    Cappella, Annalisa; Gibelli, Daniele; Muccino, Enrico; Scarpulla, Valentina; Cerutti, Elisa; Caruso, Valentina; Sguazza, Emanuela; Mazzarelli, Debora; Cattaneo, Cristina

    2015-01-27

    When estimating post-mortem interval (PMI) in forensic anthropology, the only method able to give an unambiguous result is the analysis of C-14, although the procedure is expensive. Other methods, such as luminol tests and histological analysis, can be performed as preliminary investigations and may allow the operators to gain a preliminary indication concerning PMI, but they lack scientific verification, although luminol testing has been somewhat more accredited in the past few years. Such methods in fact may provide some help as they are inexpensive and can give a fast response, especially in the phase of preliminary investigations. In this study, 20 court cases of human skeletonized remains were dated by the C-14 method. For two cases, results were chronologically set after the 1950s; for one case, the analysis was not possible technically. The remaining 17 cases showed an archaeological or historical collocation. The same bone samples were also screened with histological examination and with the luminol test. Results showed that only four cases gave a positivity to luminol and a high Oxford Histology Index (OHI) score at the same time: among these, two cases were dated as recent by the radiocarbon analysis. Thus, only two false-positive results were given by the combination of these methods and no false negatives. Thus, the combination of two qualitative methods (luminol test and microscopic analysis) may represent a promising solution to cases where many fragments need to be quickly tested.

  3. Highly sensitive trivalent copper chelate-H2O2 system for CE-chemiluminescent detection of luminol-type compounds.

    PubMed

    Fu, Zhifeng; Li, Zongyun; Xie, Haoyue; Li, Tao; Li, Cuifang

    2010-10-01

    Luminol-type compounds can be used as chemiluminescent (CL) derivatization reagents for amines, carboxylic acids and protein. Copper chelate diperiodatocuprate(III) (K5[Cu(HIO6)2], DPC) was synthesized by complexation of copper at trivalent oxidation state and periodate in a strong basic medium. It was found that DPC can greatly enhance the reaction between luminol-type compounds and H2O2 to produce very strong CL emission. Based on this fact, a rapid CE method combined with high-sensitive end-column CL detection was established to simultaneously analyze luminol and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) with wide concentration range of 3.0-300 nmol/L in 5 min. The RSDs of the signal intensity and the migration time were less than 3.9 and 7.0% for a standard sample containing 100 nmol/L luminol and ABEI (n=5), respectively. The investigation implies that DPC is a promising sensitizer for CE-CL detection of a great variety of biomolecules and drugs in biological samples after derivatization using luminol derivatives.

  4. Chemiluminescence assay of lipase activity using a synthetic substrate as proenhancer for luminol chemiluminescence reaction.

    PubMed

    Ichibangase, Tomoko; Ohba, Yoshihito; Kishikawa, Naoya; Nakashima, Kenichiro; Kuroda, Naotaka

    2004-01-01

    A novel chemiluminescence (CL) assay method for lipase (triacylglycerol lipase, E.C.3.1.1.3) activity was developed by using the lauric acid ester of 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (HDI) as a substrate. The method is based on the enhanced CL reaction of luminol-hydrogen peroxide-horseradish peroxidase (HRP) with HDI that is liberated from the substrate by enzymatic hydrolysis. To simplify the assay procedure, both the hydrolysis of the substrate and the enhanced CL reaction were performed in the same reaction mixture. Lipases from Candida cylindracea and porcine pancreas were successfully determined with the detection limits (blank signal + 3 SD) of 0.05 and 50.0 mU/tube, respectively. The method is simple and rapid, permitting the completion of single assay within 5 min. The reproducibilities obtained with replicate assays were relative standard deviations (RSDs) of <=> 4.7% for within-day and <=> 6.0% for between-day assays.

  5. A luminol-based micro-flow-injection electrochemiluminescent system to determine reactive oxygen species.

    PubMed

    Chen, Ming; Wei, Xiuhua; Tu, Yifeng

    2011-09-15

    A flow injection analysis (FIA) system with electrochemiluminescent (ECL) detection has been established. Based on a specially designed flow-through ECL cell with a very simple structure, the system possesses rapid response and high sensitivity. With luminol as the ECL reagent, the response of hydrogen peroxide (H(2)O(2)) was investigated on the developed FIA-ECL system. After optimizing the experimental conditions, such as the electric parameters, the buffer condition and the flow rate, it was demonstrated that the developed FIA-ECL system works well for quantified assays. Compared with reported works, the present results indicate that the developed FIA-ECL system has the lowest limit of detection (S/N=3) of 3.0×10(-9) mol/L for H(2)O(2), which is equal to the level of chemiluminescence (CL). The developed system was successfully used to monitor the yield of reactive oxygen species (ROSs) in water vapour during the work of an ultrasonic humidifier with H(2)O(2) as index. And the amount of ROSs in some other real samples, including tap water, drinking water and river water was detected with recoveries from 92.0% to 106%.

  6. Aluminum salts stimulate luminol-enhanced chemiluminescence production by human neutrophils.

    PubMed

    Stankovic, A; Mitrovic, D R

    1991-01-01

    Aluminum intoxication is currently thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations seen during long-term hemodialysis and aging. The hypothesis that aluminum toxicity is mediated via an increased free radical production was tested by studying the effects of two aluminum and five other metallic compounds on the production of luminol-enhanced chemiluminescence (LECL) by human neutrophils. AlCl3, Al2(SO4)3 and FeCl3 were found to stimulate LECL production by human neutrophils whereas FeCl2, CuCl, CuCl2, AuCl3 were inactive. Metal chelators such as Desferal, EDTA and DETAPA suppressed aluminum-induced stimulation and depressed cell-dependent LECL below basal levels. Sodium azide and Cytochalasin B greatly depressed both basal and aluminum-induced stimulation of LECL production, suggesting that, in this system, most of this stimulation was due to myeloperoxidase. These results suggest that high tissue aluminum concentrations may induce cell-tissue lesions by stimulating local production or release of mediators of tissue damage.

  7. Trace analysis of phosphorus in water by sorption preconcentration and luminol chemiluminescence

    PubMed

    Zui; Birks

    2000-04-01

    A new, highly sensitive chemiluminescence method for the determination of sub-ppb quantities of phosphorus in water is described. The method is based on sorption preconcentration of phosphorus as a yellow vanadomolybdophosphoric heteropoly acid (HPA) in the presence or absence of a cationic surfactant on a paper filter, followed by direct chemiluminescence detection of the phosphorus concentrate via reaction with an alkaline luminol solution. The molar ratio of cationic surfactant to HPA in the ion associate sorbed on the filter is 4:1. The detection limits for phosphorus are 0.02 microgram of P L-1 in the presence of surfactant and 0.1 microgram of P L-1 in the absence of surfactant for a sample volume of 150 mL. The calibration plot is linear from 0.06 to 1.7 micrograms of P L-1 in the presence of a surfactant, and the time required for analysis is 25 min. In the absence of surfactant, the selectivities against Si4+ and As5+ are 5 and 40 times greater than those for the standard colorimetric method based on the formation of the blue molybdophosphoric HPA. Applications of the method to the analyses of river water, seawater, and the turbine vapor condensate from a coal-fired power plant are described. It is demonstrated that the sensitivity advantage of the chemiluminescence technique can be combined with the magnesium-induced coprecipitation (MAGIC) method for a more selective measurement of soluble reactive phosphorus.

  8. Selective light-triggered chemiluminescence between fluorescent dyes and luminol, and its analytical application.

    PubMed

    Ma, Mingyang; Diao, Fangning; Zheng, Xingwang; Guo, Zhihui

    2012-08-01

    We report herein a novel chemiluminescence (CL) phenomenon triggered by light irradiation when a fluorescent dye, for example hematoporphyrin, fluorescein, eosin, or methylene blue is present in the luminol solution. A possible mechanism is proposed for the photoinduced chemiluminescence (PICL) reaction. Compared with reported methods for CL triggering, for example flow-injection, static reagent injection, and the electrochemical technique, the proposed in-situ PICL method presented has three advantages. First, the method is more selective, because the PICL signal of the target fluorescent dyes is initiated by excitation at a selective wavelength only. Second, the space and time resolution of the PICL method are better. Last, and most important, compared with injecting a reagent or inserting a electrode into the CL system to initiate the CL reaction, with the in-situ PICL method there is no physical interference with the target detecting system. All these advantages of the PICL method indicate it has many potential applications in the analytical sciences. The proposed method was applied to analysis of urine containing adrenaline. The linear range for adrenaline is 2.0 × 10(-10)-1.0 × 10(-7) g mL(-1) and the detection limit is 6.0 × 10(-11) g mL(-1).

  9. Development and application of a luminol-based nitrogen dioxide detector

    SciTech Connect

    Wendel, G.J.

    1985-01-01

    An instrument for the continuous measurement of nitrogen dioxide (NO/sub 2/) at all atmospheric concentration ranges and conditions was developed. The detector is based on the chemiluminescent reaction between 5-amino-2,3-dihydro-1,4-phthalazinedione (luminol) and NO/sub 2/ in alkaline aqueous solution. Development included the optimization of the cell design and the solution composition. Sodium sulfite (Na/sub 2/SO/sub 3/) and methanol (CH/sub 3/OH) were added to the solution to improve sensitivity and specificity. The detector was favorably compared to two different instruments measuring NO/sub 2/ by NO + O/sub 3/ chemiluminescent and by a tunable diode laser absorption spectrometry system. The detector has demonstrated a detection limit of 30 parts-per-trillion by volume (ppt) and a frequency response of 0.3 Hz. The instrument was operated for two one-month periods on Bermuda. The purpose was to study air masses from the East Coast of the United States after transport over the ocean. Average daily values were 400 ppt with values as low as 100 ppt measured. Other field experiments involved monitoring of NO/sub 2/ in ambient air in the range of 1 to 60 parts-per-billion by volume.

  10. Aircraft measurements of nitrogen dioxide and peroxyacyl nitrates using luminol chemiluminescence with fast capillary gas chromatography

    SciTech Connect

    Gaffney, J.S.; Marley, N.A.; Drayton, P.J.

    1997-09-01

    Peroxyacyl nitrates (PANs) and nitrogen dioxide (NO{sub 2}) are important trace gas species associated with photochemical air pollution. The PANs are in thermal equilibrium with the peroxyacetyl radical and NO{sub 2}. Because PANs are trapped peroxy radicals, they are an important indicator species of the photochemical age of an air parcel, as well as being a means of long-range transporting of NO{sub 2}, leading to the formation of regional ozone and other oxidants. Typically, PANs are measured by using a gas chromatograph with electron-capture detection (ECD). Once automated, this method has been shown to be reliable and quite sensitive, allowing the levels of PANs to be measured at low parts per trillion in the troposphere. Unfortunately, a number of other atmospheric gases also have strong ECD signals or act as inferences and limit the speed in which the analysis can be completed. Currently, the shortest analysis time for PAN is approx. 5 minutes with ECD. The authors recent examined the luminol detection of NO{sub 2} and PANs using gas capillary chromatography for rapid monitoring of these important trace gases. Analysis of the PANs (PAN, PPN, and PBN) and NO{sub 2} in one minute has been demonstrated in laboratory studies by using this approach. Reported here are modifications of this instrument for aircraft operation and preliminary results from test flights taken near Pasco, Washington in August of 1997.

  11. Production of luminol-reactive oxygen radicals during Plasmodium vinckei infection.

    PubMed Central

    Stocker, R; Hunt, N H; Clark, I A; Weidemann, M J

    1984-01-01

    We tested the ability of whole blood and enriched fractions of peripheral blood polymorphonuclear leukocytes obtained from mice during the course of infection with Plasmodium vinckei to produce luminol-mediated chemiluminescence in response to phagocytic and nonphagocytic stimuli. The chemiluminescence response of whole blood to all stimuli increased dramatically and nonlinearly as the infection progressed, and there was a concomitant increase (80%) and decrease (70%) in the total numbers of leukocytes and erythrocytes, respectively. The proportion of polymorphonuclear leukocytes in the total leukocyte population increased threefold. On a per cell basis and at a constant hematocrit, the chemiluminescence response of peripheral leukocytes from infected animals to phorbol myristate acetate or opsonized zymosan was only slightly greater than that of cells from uninfected animals. Polymorphonuclear leukocytes isolated from the blood of infected animals also showed no large increase per cell in chemiluminescence responsiveness. Thus, although leukocyte numbers increase during a murine malarial infection, there appears to be no major change in the capacity of individual peripheral blood leukocytes to produce activated species of oxygen. However, the physiological reduction in the total concentration of hemoglobin at high parasitemia, due to hemolysis and hemoglobin digestion by the parasites, increases the possibility of oxygen radical-mediated damage to tissues and intraerythrocytic parasites as a result of decreased antioxidant protection. PMID:6469357

  12. Increased luminol-enhanced chemiluminescence of blood monocytes and granulocytes in Hodgkin's disease.

    PubMed Central

    Tullgren, O; Giscombe, R; Holm, G; Johansson, B; Mellstedt, H; Björkholm, M

    1991-01-01

    The oxidative metabolic burst of blood monocytes and polymorphonuclear leukocytes (PMN) from 22 untreated patients with Hodgkin's disease (HD) and 18 healthy subjects were studied. Monocytes and PMN were enriched by density centrifugation and in vitro activated by zymosan. The oxidative metabolism was measured by luminol-enhanced chemiluminescence (CL). The CL of the patients' monocytes and PMN was higher than that of controls (P less than 0.01 and P less than 0.05, respectively). Patients with stage II-IV HD showed an increased blood monocyte CL as compared with stage I patients (P less than 0.05). Furthermore, patients with lymphocytic depletion or mixed cellularity subtype demonstrated an increased CL of PMN as compared with the remainder. Enhanced CL of phagocytes has been observed in chronic inflammatory disease and can be induced by various serum factors such as monokines and immune complexes. The present study demonstrates an increased CL of blood-borne phagocytic cells in untreated HD. Furthermore, CL of blood monocytes and PMN correlated to tumour burden and histologic subtype, respectively. PMID:1893624

  13. Aircraft measurements of nitrogen dioxide and peroxyacetyl nitrates using luminol chemiluminescence with fast capillary gas chromatography

    SciTech Connect

    Gaffney, J.S.; Marley, N.A.; Steele, H.D.; Drayton, P.J.; Hubbe, J.M.

    1999-10-01

    Fast capillary gas chromatography with luminol detection has been used to make airborne measurements of nitrogen dioxide (NO{sub 2}) and peroxyacetyl nitrate (PAN). The analysis system allows for the simultaneous measurement of NO{sub 2} and peroxyacyl nitrates (PANs) with time resolution of less than 1 min, and improvement of a factor of 4--5 over previously reported methods using electron capture detection. Data presented were taken near Pasco, Washington, in August 1997, during a test flight onboard the US Department of Energy G-1 aircraft. The authors report measurements of NO{sub 2} in the boundary layer in a paper mill plume and a plume from a grass fire, in addition to analyses for free tropospheric NO{sub 2} and PAN. Ratios of PAN/NO{sub 2} were observed to increase with altitude (decreasing temperature) and to reach values of 2--4 above the boundary layer, consistent with the thermal equilibrium of the peroxyacetyl radical and NO{sub 2} and PAN. Estimates for the peroxyacetyl radical in the continental free troposphere, calculated from this equilibrium, were found to be in the range of 10{sup 4}--10{sup 5} molecules per cubic centimeter. These results demonstrate the application of this approach for airborne measurements of NO{sub 2} and PAN in a wide range of field study scenarios.

  14. Peculiarities of luminol- and lucigenin-dependent photon emission from nondiluted human blood

    NASA Astrophysics Data System (ADS)

    Voeikov, Vladimir L.; Novikov, Cyril N.

    1998-01-01

    Comparison of lucigenin- and luminol-dependent chemiluminescence (LC-CL and LM-CL, respectively) in nondiluted healthy donors' blood revealed significant differences in their patterns. LM-CL was low in fresh blood and disappeared after it storage for 3 hours. LC-CL was already high in fresh blood and was steadily increasing with blood storage. Serial dilution of blood with saline after addition of chemiluminescence indicators resulted in elevation of LM-CL, but decrease in LC-CL. LM-CL elevation after the initiation of respiratory burst (RB) in blood with zymosan was observed only in aerated samples and immediately dropped down when air supply to a blood sample was ceased. On the contrary, LM-CL did not depend on air supply to a blood sample for about 30 min. after RB initiation. The results suggest that there are at least two mechanisms for reactive oxygen species production in nondiluted blood. The first one is reflected predominantly by LM-CL. It is activated during RB and uses prevalently oxygen dissolved in cell medium. Another one is reflected predominantly by LC- LM. It does not depend upon initiation of RB in neutrophils, operates in blood constantly, and uses oxygen supplied by erythrocytes. It needs blood integrity for its manifestation.

  15. Peculiarities of luminol- and lucigenin-dependent photon emission from nondiluted human blood

    NASA Astrophysics Data System (ADS)

    Voeikov, Vladimir L.; Novikov, Cyrill N.

    1997-12-01

    Comparison of lucigenin- and luminol-dependent chemiluminescence (LC-CL and LM-CL, respectively) in nondiluted healthy donors' blood revealed significant differences in their patterns. LM-CL was low in fresh blood and disappeared after it storage for 3 hours. LC-CL was already high in fresh blood and was steadily increasing with blood storage. Serial dilution of blood with saline after addition of chemiluminescence indicators resulted in elevation of LM-CL, but decrease in LC-CL. LM-CL elevation after the initiation of respiratory burst (RB) in blood with zymosan was observed only in aerated samples and immediately dropped down when air supply to a blood sample was ceased. On the contrary, LM-CL did not depend on air supply to a blood sample for about 30 min. after RB initiation. The results suggest that there are at least two mechanisms for reactive oxygen species production in nondiluted blood. The first one is reflected predominantly by LM-CL. It is activated during RB and uses prevalently oxygen dissolved in cell medium. Another one is reflected predominantly by LC- LM. It does not depend upon initiation of RB in neutrophils, operates in blood constantly, and uses oxygen supplied by erythrocytes. It needs blood integrity for its manifestation.

  16. Luminol fluorescence quenching in biomimicking environments: sequestration of fluorophore in hydrophobic domain.

    PubMed

    Moyon, N Shaemningwar; Mitra, Sivaprasad

    2011-08-25

    The photophysical behavior of luminol (LH(2)) was studied in a variety of biologically relevant systems ranging from surfactants, cyclodextrin, and proteins using steady-state and time-resolved fluorescence spectroscopy. It was shown that, out of two possible LH(2) conformers present in solution, the sequestration of relatively less polar structure into the hydrophobic domain of biological media is the primary reason for decrease in fluorescence intensity. The efficacy of LH(2) fluorescence quenching is substantially higher in micellar subdomain of cationic surfactant and depends on the nature of the headgroup. The thermodynamic parameters like enthalpy (ΔH) and entropy (ΔS) change, etc., corresponding to the binding of LH(2) in the model water-soluble protein, bovine serum albumin (BSA), were estimated by performing the fluorescence titration experiment at different temperatures. The involvement of subdomain IA and IIA of BSA in LH(2) binding was confirmed from the ligand replacement process with bilirubin (BIL). The difference in ligand binding with structurally homologous human serum albumin (HSA) is discussed in terms of positive cooperativity among these two binding domains of BSA with a Hill coefficient (n(H)) value of 2.26 ± 0.18 and a half-maximal concentration (K(0.5)) of 5.74 ± 0.23 μM at 298 K.

  17. Effect of ascorbic acid on the monosodium glutamate-induced neurobehavioral changes in periadolescent rats.

    PubMed

    Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Paval, Jaijesh; Nayak, Satheesha

    2010-01-01

    In the current study we evaluated adverse effects of monosodium glutamate (MSG) on memory formation and its retrieval as well as the role of ascorbic acid (Vitamin-C) in prevention of MSG-induced alteration of neurobehavioral performance in periadolescent rats. Healthy male albino Wistar rats (4-6 weeks old), were randomly allotted in four groups. Group I: normal control, who remained in their homecage throughout the experimental period. Group II: vehicle control, who were orally administered with normal saline for three weeks. Group III: MSG, who were orally administered with aqueous solution of MSG (2 mg/g b.w/day), for three weeks. Group IV: MSG+AA, who were administered with aqueous solution of MSG, and subsequently by ascorbic acid (100 mg/kg b.w/day) orally for three weeks. After the experimental period, all animals from all groups were first tested for anxiety followed by passive avoidance behavior. MSG significantly altered the neurobehavioral performance in rats. The alteration manifested as less time spent on the open arm during the EPM test and shorter entrance latency to the dark compartment during the passive avoidance task. All behavioral changes were significantly prevented by simultaneous administration of ascorbic acid with MSG. The present data point to the neuroprotective role of ascorbic acid. The ascorbic acid can be used as a therapeutic agent in various cognitive deficits (Fig. 5, Ref. 25). Full Text (Free, PDF) www.bmj.sk.

  18. Monosodium glutamate-sensitive hypothalamic neurons contribute to the control of bone mass

    NASA Technical Reports Server (NTRS)

    Elefteriou, Florent; Takeda, Shu; Liu, Xiuyun; Armstrong, Dawna; Karsenty, Gerard

    2003-01-01

    Using chemical lesioning we previously identified hypothalamic neurons that are required for leptin antiosteogenic function. In the course of these studies we observed that destruction of neurons sensitive to monosodium glutamate (MSG) in arcuate nuclei did not affect bone mass. However MSG treatment leads to hypogonadism, a condition inducing bone loss. Therefore the normal bone mass of MSG-treated mice suggested that MSG-sensitive neurons may be implicated in the control of bone mass. To test this hypothesis we assessed bone resorption and bone formation parameters in MSG-treated mice. We show here that MSG-treated mice display the expected increase in bone resorption and that their normal bone mass is due to a concomitant increase in bone formation. Correction of MSG-induced hypogonadism by physiological doses of estradiol corrected the abnormal bone resorptive activity in MSG-treated mice and uncovered their high bone mass phenotype. Because neuropeptide Y (NPY) is highly expressed in MSG-sensitive neurons we tested whether NPY regulates bone formation. Surprisingly, NPY-deficient mice had a normal bone mass. This study reveals that distinct populations of hypothalamic neurons are involved in the control of bone mass and demonstrates that MSG-sensitive neurons control bone formation in a leptin-independent manner. It also indicates that NPY deficiency does not affect bone mass.

  19. REVIEW OF EXPERIMENTAL STUDIES INVESTIGATING THE RATE OF STRONTIUM AND ACTINIDE ADSORPTION BY MONOSODIUM TITANATE

    SciTech Connect

    Hobbs, D.

    2010-10-01

    A number of laboratory studies have been conducted to determine the influence of mixing and mixing intensity, solution ionic strength, initial sorbate concentrations, temperature, and monosodium titanate (MST) concentration on the rates of sorbate removal by MST in high-level nuclear waste solutions. Of these parameters, initial sorbate concentrations, ionic strength, and MST concentration have the greater impact on sorbate removal rates. The lack of a significant influence of mixing and mixing intensity on sorbate removal rates indicates that bulk solution transport is not the rate controlling step in the removal of strontium and actinides over the range of conditions and laboratory-scales investigated. However, bulk solution transport may be a significant parameter upon use of MST in a 1.3 million-gallon waste tank such as that planned for the Small Column Ion Exchange (SCIX) program. Thus, Savannah River National Laboratory (SRNL) recommends completing the experiments in progress to determine if mixing intensity influences sorption rates under conditions appropriate for this program. Adsorption models have been developed from these experimental studies that allow prediction of strontium (Sr), plutonium (Pu), neptunium (Np) and uranium (U) concentrations as a function of contact time with MST. Fairly good agreement has been observed between the predicted and measured sorbate concentrations in the laboratory-scale experiments.

  20. Time-quality tracking of monosodium glutamate, sodium saccharin, and a citric acid-saccharin mixture.

    PubMed

    Zwillinger, S A; Halpern, B P

    1991-05-01

    The temporal patterns of taste-quality descriptors evoked by 1000-ms duration stimulus liquids flowed through a closed delivery system over the anterodorsal tongue tip region were indicated using touch-typing on a computer keyboard. Single keys corresponded to the taste words of a 23 item code. A computer monitor displayed for subjects the keys pressed and when they were pressed, starting at stimulus delivery. For 2 mM sodium saccharin (NaSac), 75% of the responses were "sweet," 6.5% "sugar"; for NaSac in 10 mM citric acid (ArtLem), 43% "sour," 20% "citrus," and 11% "sugar"; for 214 mM monosodium glutamate (MSG), 28% "salty," 14% "sour," and 10% 1st "soapy," then "no taste," and finally "bitter." Distilled water received "no taste" on all trials. Response durations were 657 ms for ArtLem, 594 ms for NaSac, 577 ms for MSG. MSG yielded multiple quality responses on 25.5% of the trials; ArtLem, 9%; and NaSac, 1%. These results are compared with temporal patterns for taste intensity and with unrestricted verbal descriptions of the solutions.

  1. The effects of intra-articular resiniferatoxin on monosodium iodoacetate-induced osteoarthritic pain in rats

    PubMed Central

    Kim, Youngkyung; Kim, Eun-hye; Lee, Kyu Sang; Lee, Koeun; Park, Sung Ho; Na, Sook Hyun; Ko, Cheolwoong; Yooon, Young Wook

    2016-01-01

    This study was performed to investigate whether an intra-articular injection of transient receptor potential vanilloid 1 (TRPV1) receptor agonist, resiniferatoxin (RTX) would alleviate behavioral signs of arthritic pain in a rat model of osteoarthritis (OA). We also sought to determine the effect of RTX treatment on calcitonin gene-related peptide (CGRP) expression in the spinal cord. Knee joint inflammation was induced by intra-articular injection of monosodium iodoacetate (MIA, 8 mg/50 µl) and weight bearing percentage on right and left hindpaws during walking, paw withdrawal threshold to mechanical stimulation, and paw withdrawal latency to heat were measured to evaluate pain behavior. Intra-articular administration of RTX (0.03, 0.003 and 0.0003%) at 2 weeks after the induction of knee joint inflammation significantly improved reduction of weight bearing on the ipsilateral hindlimb and increased paw withdrawal sensitivity to mechanical and heat stimuli. The reduction of pain behavior persisted for 3~10 days according to each behavioral test. The MIA-induced increase in CGRP immunoreactivity in the spinal cord was decreased by RTX treatment in a dose-dependent manner. The present study demonstrated that a single intra-articular administration of RTX reduced pain behaviors for a relatively long time in an experimental model of OA and could normalize OA-associated changes in peptide expression in the spinal cord. PMID:26807032

  2. Vitamin C Protects Chondrocytes against Monosodium Iodoacetate-Induced Osteoarthritis by Multiple Pathways.

    PubMed

    Chiu, Pu-Rong; Hu, Yu-Chen; Huang, Tzu-Ching; Hsieh, Bau-Shan; Yeh, Jou-Pei; Cheng, Hsiao-Ling; Huang, Li-Wen; Chang, Kee-Lung

    2016-12-27

    Osteoarthritis (OA) is the most prevalent joint disease. Dietary intake of vitamin C relates to a reduction in cartilage loss and OA. This study examined the efficacy of vitamin C to prevent OA with the in vitro chondrosarcoma cell line (SW1353) and the in vivo monosodium iodoacetate (MIA)-induced OA rat. Results demonstrated that, in SW1353 cells, treatment with 5 μM MIA inhibited cell growth and increased oxidative stress, apoptosis, and proteoglycan loss. In addition, the expression levels of the pro-inflammatory cytokines IL-6, IL-17A, and TNF-α and matrix metalloproteinases (MMPs) MMP-1, MMP-3, and MMP-13 were increased. All of these MIA-induced changes could be prevented with treatment of 100 μM vitamin C. In an animal model, intra-articular injection of MIA-induced cartilage degradation resembled the pathological changes of OA, and treatment of vitamin C could lessen these changes. Unexpectedly, vitamin C's effects did not strengthen with the increasing dosage, while the 100 mg/kg dosage was more efficient than the 200 or 300 mg/kg dosages. Vitamin C possessed multiple capacities for prevention of OA progress, including a decrease in apoptosis and in the expression of pro-inflammatory cytokines and MMPs in addition to the well-known antioxidation.

  3. Use of monosodium glutamate by-product in cow diet on performance of lactating dairy cows.

    PubMed

    Padunglerk, Achira; Prasanpanich, Somkiert; Kongmun, Phongthorn

    2017-01-01

    Eight multiparous lactating Holstein cows were randomly assigned in a 4 × 4 replicated Latin square design to receive four dietary treatments. The dietary treatments were monosodium glutamate by-product (MSGB) replacement for soybean meal in concentrate at four levels: MSGB replacement at 0, 20, 40 and 60%, respectively. Pangola hay was given on an ad libitum basis. It was found that total dry matter intake, concentrate intake, pangola hay intake and all apparent digestibilities were not different among treatments. Ammonia nitrogen concentration in the rumen at 4 h post-feeding was significantly different, in which the 0% treatment had the highest (P < 0.05) while the 20% treatment had the lowest. Milk fat percentage was the highest (P < 0.05) in the 0% treatment. MSGB replacement at 40% and 60% were shown to be the lowest (P < 0.05) feed cost for milk production, and profitability of milk production was the highest (P < 0.05) for the 60% treatment. Based on this experiment, it could be concluded that MSGB replacement for soybean meal at 20-60% in the feed for dairy cows presented no negative effects on their performances. In addition, it could decrease feed cost 2.9-17.3% and increase milk production profit up to 33.3% in the 60% treatment.

  4. Dose-dependent uptake, elimination, and toxicity of monosodium methanearsonate in adult zebra finches (Taeniopygia guttata).

    PubMed

    Albert, Courtney A; Williams, Tony D; Morrissey, Christy A; Lai, Vivian W M; Cullen, William R; Elliott, John E

    2008-03-01

    Monosodium methanearsonate (MSMA), an arsenic-based pesticide, has been used for the past 10 years in attempts to suppress mountain pine beetle (Dendroctonus ponderosae) outbreaks in British Columbia, Canada. Previous studies have shown that cavity nesting forest birds such as woodpeckers forage and breed in MSMA treated pine stands. Here we examined the effects of MSMA in the laboratory using the zebra finch (Taeniopygia guttata), with the objective to examine tissue distribution and sublethal toxic effects in a model avian species. Zebra finches were exposed to this pesticide at doses similar to those found in bark beetle samples from MSMA stands of trees treated in the southern interior of British Columbia (8, 24, and 72 microg/g/d and a control group). Results showed high excretion (>90%) of arsenic in all dose groups, as well as dose-dependent trends in accumulation of arsenic in the blood (p < 0.001) and specific tissues. Monomethylarsonic acid, MMA (V), was the predominant form of arsenic in the blood plasma. Dimethylarsinic acid was the major form of arsenic found in the liver (83%) and kidney (61%) tissues. The brain tissue contained primarily the MMA (V) form (57%). Significant weight loss occurred in the two highest dose groups (p < 0.05). Birds in the highest dose group lost up to 15% of initial body mass.

  5. Vitamin C Protects Chondrocytes against Monosodium Iodoacetate-Induced Osteoarthritis by Multiple Pathways

    PubMed Central

    Chiu, Pu-Rong; Hu, Yu-Chen; Huang, Tzu-Ching; Hsieh, Bau-Shan; Yeh, Jou-Pei; Cheng, Hsiao-Ling; Huang, Li-Wen; Chang, Kee-Lung

    2016-01-01

    Osteoarthritis (OA) is the most prevalent joint disease. Dietary intake of vitamin C relates to a reduction in cartilage loss and OA. This study examined the efficacy of vitamin C to prevent OA with the in vitro chondrosarcoma cell line (SW1353) and the in vivo monosodium iodoacetate (MIA)-induced OA rat. Results demonstrated that, in SW1353 cells, treatment with 5 μM MIA inhibited cell growth and increased oxidative stress, apoptosis, and proteoglycan loss. In addition, the expression levels of the pro-inflammatory cytokines IL-6, IL-17A, and TNF-α and matrix metalloproteinases (MMPs) MMP-1, MMP-3, and MMP-13 were increased. All of these MIA-induced changes could be prevented with treatment of 100 μM vitamin C. In an animal model, intra-articular injection of MIA-induced cartilage degradation resembled the pathological changes of OA, and treatment of vitamin C could lessen these changes. Unexpectedly, vitamin C’s effects did not strengthen with the increasing dosage, while the 100 mg/kg dosage was more efficient than the 200 or 300 mg/kg dosages. Vitamin C possessed multiple capacities for prevention of OA progress, including a decrease in apoptosis and in the expression of pro-inflammatory cytokines and MMPs in addition to the well-known antioxidation. PMID:28035982

  6. Functionalization of sawdust with monosodium glutamate for enhancing its malachite green removal capacity.

    PubMed

    Gong, Renmin; Feng, Min; Zhao, Jiajing; Cai, Wenkai; Liu, Lingling

    2009-01-01

    In this paper, waste sawdust was functionalized by monosodium glutamate for improving its cationic sorption capacity. The functionalized sawdust (FS) and crude sawdust (CS) were compared for their malachite green (MG) sorption behaviors with a batch system. The effects of various experimental parameters (e.g. initial pH, sorbent dose, dye concentration, contact time, and temperature etc.) were investigated and the sorption kinetic and thermodynamic characteristics were understood. The MG removal ratios on FS and on CS increased with increasing initial pH and came up to the maximum value beyond pH 6 for FS and pH 8 for CS, respectively. The ratio of sorbed MG kept above 95% for 250 mg/l of MG solution when 2.0 g/l or more of FS was used. The MG removal percentage decreased more on CS than on FS with increasing initial MG concentration. The isothermal data of MG sorbed on FS and on CS followed the Langmuir model. By functionalizing, the sorption capacity (Q(m)) of sawdust for MG was increased from 85.47 to 196.08 mg/g and the sorption equilibrium time of MG was shortened from 23 to 4.5 h. The MG sorption processes on FS and on CS followed the pseudo-second-order rate kinetics. The sorptions of MG on FS and on CS were spontaneous and exothermic processes and lower temperatures were favorable for the sorption processes.

  7. Does monosodium glutamate interact with macronutrient composition to influence subsequent appetite?

    PubMed

    Masic, Una; Yeomans, Martin R

    2013-05-27

    The influence of flavour enhancers such as monosodium glutamate (MSG) on satiation and satiety is unclear, and the present study aimed to explore this by examining the effects consumption of soups varying in MSG (1% MSG added or no MSG) and macronutrient content (added carbohydrate, protein or control) had on appetite. 24 non-obese, low-restraint male participants consumed a fixed portion of soup and rated their appetite before, immediately after intake and at 15 minute intervals for 120 min post-ingestion across six sessions. Added MSG significantly increased flavour pleasantness and tended to result in a smaller decrease in hunger immediately after soup ingestion. MSG also reduced rather than enhanced feelings of fullness immediately after ingestion of the high protein soup. As expected, hunger increased, and fullness decreased, over the subsequent 120 min, but the increase in hunger was significantly lower in the MSG than no-MSG conditions with the protein soup between 30 and 60 min post-ingestion. Overall these data suggest that MSG may have a bi-phasic effect on appetite, with reduced satiation mediated by effects on palatability, but potential for enhanced post-ingestive satiety particularly in the context of protein ingestion.

  8. Subcutaneous administration of monosodium glutamate to pregnant mice reduces weight gain in pups during lactation.

    PubMed

    Park, Ji-Hun; Choi, Tae-Saeng

    2016-04-01

    Administering monosodium glutamate (MSG) to neonatal rodents induces obesity and type 2 diabetes. In addition, several studies have shown that MSG administered to pregnant animals can cross the placenta and reach the foetus. The present study was performed to investigate the effects of administering MSG to pregnant ICR mice on dam and neonatal growth. Pregnant mice were treated with 60 or 120 mg MSG once daily from day 5 of pregnancy to one day before parturition by subcutaneous injection. In addition, the body weights of the neonates were determined until nine weeks of age. The birth weights of neonates were not different between the control and MSG-treated groups. However, MSG treatment resulted in a lower body weight gain of neonates during lactation. In addition, this underweight of the MSG-treated group at weaning returned to normal compared with the control group at five weeks of age. Cross-fostering experiments indicated that the lower body weight gain of neonates in the MSG-treated group during lactation was due to its effects on the dam. Serum prolactin levels and mammary gland development of the mice were examined next to determine the reasons for this lactation problem. Although there were no differences in prolactin levels, morphological analyses of the mammary glands revealed apparent differences, including low numbers and altered phenotype of alveoli, between the control and MSG-treated groups. Taken together, our results show that treating pregnant mice with excess MSG induced lower neonate body weight gain during lactation.

  9. Monosodium glutamate (MSG): a villain and promoter of liver inflammation and dysplasia.

    PubMed

    Nakanishi, Yuko; Tsuneyama, Koichi; Fujimoto, Makoto; Salunga, Thucydides L; Nomoto, Kazuhiro; An, Jun-Ling; Takano, Yasuo; Iizuka, Seiichi; Nagata, Mitsunobu; Suzuki, Wataru; Shimada, Tsutomu; Aburada, Masaki; Nakano, Masayuki; Selmi, Carlo; Gershwin, M Eric

    2008-01-01

    Chronic inflammation is a common theme in a variety of disease pathways, including autoimmune diseases. The pathways of chronic inflammation are well illustrated by nonalcoholic steatohepatitis (NASH), which is of a serious concern due to its increasing prevalence in the westernized world and its direct correlation with lifestyle factors, particularly diet. Importantly, NASH may ultimately lead to the development of hepatocellular carcinoma. We previously reported that injection of monosodium glutamate (MSG) in ICR mice leads to the development of significant inflammation, central obesity, and type 2 diabetes. To directly address the long-term consequences of MSG on inflammation, we have performed serial analysis of MSG-injected mice and focused in particular on liver pathology. By 6 and 12 months of age, all MSG-treated mice developed NAFLD and NASH-like histology, respectively. In particular, the murine steatohepatitis at 12 months was virtually undistinguishable from human NASH. Further, dysplastic nodular lesions were detected in some cases within the fibrotic liver parenchyma. We submit that MSG treatment of mice induces obesity and diabetes with steatosis and steatohepatitis resembling human NAFLD and NASH with pre-neoplastic lesions. These results take on considerable significance in light of the widespread usage of dietary MSG and we suggest that MSG should have its safety profile re-examined and be potentially withdrawn from the food chain.

  10. Protective effects of N-acetylcysteine against monosodium glutamate-induced astrocytic cell death.

    PubMed

    Park, Euteum; Yu, Kyoung Hwan; Kim, Do Kyung; Kim, Seung; Sapkota, Kumar; Kim, Sung-Jun; Kim, Chun Sung; Chun, Hong Sung

    2014-05-01

    Monosodium glutamate (MSG) is a flavor enhancer, largely used in the food industry and it was reported to have excitotoxic effects. Higher amounts of MSG consumption have been related with increased risk of many diseases, including Chinese restaurant syndrome and metabolic syndromes in human. This study investigated the protective effects of N-acetylcysteine (NAC) on MSG-induced cytotoxicity in C6 astrocytic cells. MSG (20 mM)-induced reactive oxygen species (ROS) generation and apoptotic cell death were significantly attenuated by NAC (500 μM) pretreatment. NAC effectively inhibited the MSG-induced mitochondrial membrane potential (MMP) loss and intracellular reduced glutathione (GSH) depletion. In addition, NAC significantly attenuated MSG-induced endoplasmic reticulum (ER) stress markers, such as XBP1 splicing and CHOP, PERK, and GRP78 up-regulation. Furthermore, NAC prevented the changes of MSG-induced Bcl-2 expression level. These results suggest that NAC can protect C6 astrocytic cells against MSG-induced oxidative stress, mitochondrial dysfunction, and ER stress.

  11. Does monosodium glutamate really cause headache? : a systematic review of human studies.

    PubMed

    Obayashi, Yoko; Nagamura, Yoichi

    2016-01-01

    Although monosodium glutamate (MSG) is classified as a causative substance of headache in the International Classification of Headache Disorders 3rd edition (ICHD-III beta), there is no literature in which causal relationship between MSG and headache was comprehensively reviewed. We performed systematic review of human studies which include the incidence of headache after an oral administration of MSG. An analysis was made by separating the human studies with MSG administration with or without food, because of the significant difference of kinetics of glutamate between those conditions (Am J Clin Nutr 37:194-200, 1983; J Nutr 130:1002S-1004S, 2000) and there are some papers which report the difference of the manifestation of symptoms after MSG ingestion with or without food (Food Chem Toxicol 31:1019-1035, 1993; J Nutr 125:2891S-2906S, 1995). Of five papers including six studies with food, none showed a significant difference in the incidence of headache except for the female group in one study. Of five papers including seven studies without food, four studies showed a significant difference. Many of the studies involved administration of MSG in solution at high concentrations (>2 %). Since the distinctive MSG is readily identified at such concentrations, these studies were thought not to be properly blinded. Because of the absence of proper blinding, and the inconsistency of the findings, we conclude that further studies are required to evaluate whether or not a causal relationship exists between MSG ingestion and headache.

  12. Metabolomic profiling of urinary changes in mice with monosodium glutamate-induced obesity.

    PubMed

    Pelantová, Helena; Bártová, Simona; Anýž, Jiří; Holubová, Martina; Železná, Blanka; Maletínská, Lenka; Novák, Daniel; Lacinová, Zdena; Šulc, Miroslav; Haluzík, Martin; Kuzma, Marek

    2016-01-01

    Obesity with related complications represents a widespread health problem. The etiopathogenesis of obesity is often studied using numerous rodent models. The mouse model of monosodium glutamate (MSG)-induced obesity was exploited as a model of obesity combined with insulin resistance. The aim of this work was to characterize the metabolic status of MSG mice by NMR-based metabolomics in combination with relevant biochemical and hormonal parameters. NMR analysis of urine at 2, 6, and 9 months revealed altered metabolism of nicotinamide and polyamines, attenuated excretion of major urinary proteins, increased levels of phenylacetylglycine and allantoin, and decreased concentrations of methylamine in urine of MSG-treated mice. Altered levels of creatine, citrate, succinate, and acetate were observed at 2 months of age and approached the values of control mice with aging. The development of obesity and insulin resistance in 6-month-old MSG mice was also accompanied by decreased mRNA expressions of adiponectin, lipogenetic and lipolytic enzymes and peroxisome proliferator-activated receptor-gamma in fat while mRNA expressions of lipogenetic enzymes in the liver were enhanced. At the age of 9 months, biochemical parameters of MSG mice were normalized to the values of the controls. This fact pointed to a limited predictive value of biochemical data up to age of 6 months as NMR metabolomics confirmed altered urine metabolic composition even at 9 months.

  13. Experience-induced changes in taste identification of monosodium glutamate (MSG) are reversible.

    PubMed

    Kobayashi, Chiyoko; Kennedy, Linda M; Halpern, Bruce P

    2006-05-01

    A few studies have reported experience-inducible changes in human taste and olfactory sensitivities. However, no study thus far has systematically characterized the stability of the enhanced sensitivities. In our previous study, we found increases in taste identification ability for monosodium glutamate (MSG) in subjects who had been briefly exposed to MSG in food for 10 days. Here, we tested the temporal stability of the enhanced taste identification ability. First, we exposed a group of 20 subjects to MSG in food and then compared their sensitivities to MSG with those of a control group. When tested on day 11 or 12, the mean MSG taste identification ability of the MSG-exposed group was significantly higher than the control group. Next, 11 of the subjects who were exposed to MSG in food initially, and then stopped being exposed performed significantly poorer in identifying MSG after 10 days of the nonexposure than they did 10 days before. In contrast, nine subjects who were exposed to MSG initially and continued being exposed maintained their high identification levels. These results support earlier finding of the plasticity in the taste identification of MSG and show that the enhanced identification ability can be reversed rapidly when MSG exposure is not sustained.

  14. Neonatal exposure to monosodium glutamate induces morphological alterations in suprachiasmatic nucleus of adult rat.

    PubMed

    Rojas-Castañeda, Julio César; Vigueras-Villaseñor, Rosa María; Chávez-Saldaña, Margarita; Rojas, Patricia; Gutiérrez-Pérez, Oscar; Rojas, Carolina; Arteaga-Silva, Marcela

    2016-02-01

    Neonatal exposure to monosodium glutamate (MSG) induces circadian disorders in several physiological and behavioural processes regulated by the suprachiasmatic nucleus (SCN). The objective of this study was to evaluate the effects of neonatal exposure to MSG on locomotor activity, and on morphology, cellular density and expression of proteins, as evaluated by optical density (OD), of vasopressin (VP)-, vasoactive intestinal polypeptide (VIP)- and glial fibrillary acidic protein (GFAP)-immunoreactive cells in the SCN. Male Wistar rats were used: the MSG group was subcutaneously treated from 3 to 10 days of age with 3.5 mg/g/day. Locomotor activity was evaluated at 90 days of age using 'open-field' test, and the brains were processed for immunohistochemical studies. MSG exposure induced a significant decrease in locomotor activity. VP- and VIP-immunoreactive neuronal densities showed a significant decrease, while the somatic OD showed an increase. Major axes and somatic area were significantly increased in VIP neurons. The cellular and optical densities of GFAP-immunoreactive sections of SCN were significantly increased. These results demonstrated that newborn exposure to MSG induced morphological alterations in SCN cells, an alteration that could be the basis for behavioural disorders observed in the animals.

  15. Excitotoxicity triggered by neonatal monosodium glutamate treatment and blood-brain barrier function.

    PubMed

    Gudiño-Cabrera, Graciela; Ureña-Guerrero, Monica E; Rivera-Cervantes, Martha C; Feria-Velasco, Alfredo I; Beas-Zárate, Carlos

    2014-11-01

    It is likely that monosodium glutamate (MSG) is the excitotoxin that has been most commonly employed to characterize the process of excitotoxicity and to improve understanding of the ways that this process is related to several pathological conditions of the central nervous system. Excitotoxicity triggered by neonatal MSG treatment produces a significant pathophysiological impact on adulthood, which could be due to modifications in the blood-brain barrier (BBB) permeability and vice versa. This mini-review analyzes this topic through brief descriptions about excitotoxicity, BBB structure and function, role of the BBB in the regulation of Glu extracellular levels, conditions that promote breakdown of the BBB, and modifications induced by neonatal MSG treatment that could alter the behavior of the BBB. In conclusion, additional studies to better characterize the effects of neonatal MSG treatment on excitatory amino acids transporters, ionic exchangers, and efflux transporters, as well as the role of the signaling pathways mediated by erythropoietin and vascular endothelial growth factor in the cellular elements of the BBB, should be performed to identify the mechanisms underlying the increase in neurovascular permeability associated with excitotoxicity observed in several diseases and studied using neonatal MSG treatment.

  16. Monosodium glutamate in chicken and beef stock cubes using high-performance liquid chromatography.

    PubMed

    Demirhan, Buket Er; Demirhan, Burak; Sönmez, Ceren; Torul, Hilal; Tamer, Uğur; Yentür, Gülderen

    2015-01-01

    In this survey monosodium glutamate (MSG) levels in chicken and beef stock cube samples were determined. A total number of 122 stock cube samples (from brands A, B, C, D) were collected from local markets in Ankara, Turkey. High-performance liquid chromatography with diode array detection (HPLC-DAD) was used for quantitative MSG determination. Mean MSG levels (±SE) in samples of A, B, C and D brands were 14.6 ± 0.2 g kg⁻¹, 11.9 ± 0.3 g kg⁻¹, 9.7 ± 0.1 g kg⁻¹ and 7.2 ± 0.1 g kg⁻¹, respectively. Differences between mean levels of brands were significant. Also, mean levels of chicken stock cube samples were lower than in beef stock cubes. Maximum limits for MSG in stock cubes are not specified in the Turkish Food Codex (TFC). Generally the limit for MSG in foods (except some foods) is established as 10 g kg⁻¹ (individually or in combination).

  17. Microbial treatment of the monosodium glutamate wastewater by Lipomyces starkeyi to produce microbial lipid.

    PubMed

    Liu, Jun-Xian; Yue, Qin-Yan; Gao, Bao-Yu; Ma, Zuo-Hao; Zhang, Pei-Dong

    2012-02-01

    The monosodium glutamate (MSG) wastewater as a medium was treated by Lipomyces starkeyi to produce microbial lipid in the study. The effect of related factors (initial glucose concentration, inoculation concentration, initial culture pH, and cultivation time) on biomass, lipid production and lipid content was discussed, respectively. According to the experiments, the optimal fermentation conditions were determined: addition of 80g/L glucose, 10% inoculation concentration, initial pH about 5.0, incubation time 96h. Under this condition, the biomass production reached up to 4.61g/L, lipid production and lipid content was 1.14g/L and 24.73%, respectively. Simultaneously, protein and COD removal rate was 78.60% and 74.96%, respectively. The main composition of fatty acid in the resultant lipid was analyzed by gas chromatography-mass spectrometry, which showed: oleic acid (C18:1) 35.85%, palmitic acid (C16:0) 19.91%, palmitoleic acid (C16:1) 17.65%, and myristic acid (C14:0) 16.03%.

  18. Interactions between tenocytes and monosodium urate monohydrate crystals: implications for tendon involvement in gout.

    PubMed

    Chhana, Ashika; Callon, Karen E; Dray, Michael; Pool, Bregina; Naot, Dorit; Gamble, Greg D; Coleman, Brendan; McCarthy, Geraldine; McQueen, Fiona M; Cornish, Jillian; Dalbeth, Nicola

    2014-09-01

    Advanced imaging studies have demonstrated that urate deposition in periarticular structures, such as tendons, is common in gout. The aim of this study was to investigate the effects of monosodium urate monohydrate (MSU) crystals on tenocyte viability and function. The histological appearance of tendons in joints affected by advanced gout was examined using light microscopy. In vitro, colorimetric assays and flow cytometry were used to assess cell viability in primary rat and primary human tenocytes cultured with MSU crystals. Real-time PCR was used to determine changes in the relative mRNA expression levels of tendon-related genes, and Sirius red staining was used to measure changes in collagen deposition in primary rat tenocytes. In joint samples from patients with gout, MSU crystals were identified within the tendon, adjacent to and invading into tendon, and at the enthesis. MSU crystals reduced tenocyte viability in a dose-dependent manner. MSU crystals decreased the mRNA expression of tendon collagens, matrix proteins and degradative enzymes and reduced collagen protein deposition by tenocytes. These data indicate that MSU crystals directly interact with tenocytes to reduce cell viability and function. These interactions may contribute to tendon damage in people with advanced gout. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  19. Effect of monosodium methanarsonate application on cuticle wax content of cocklebur and cotton plants.

    PubMed

    Keese, Renee J; Camper, N Dwight

    2006-01-01

    Leaf cuticle waxes were extracted from monosodium methanearsonate (MSMA)-resistant (R) and -susceptible (S) common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) plants at 0, 3, 5, and 7 days after treatment (DAT) following 1x and 2x MSMA applications. Wax constituents were analyzed by gas chromatography (GC) with flame ionization detection and compared to alkane and alcohol standards of carbon lengths varying from C21 to C30. Differences in waxes were calculated and reported as change per ng mm2-1. Tricosane (C23) was found to increase following MSMA applications. All other alkanes decreased by 7 DAT, with some showing a linear effect over time in the R-cocklebur. Alcohol constituents were also observed to decrease by 7 DAT. Total arsenic in the extracted wax fraction was determined, with greatest quantities detected in the R-cocklebur. Wax changes are not believed to play a role in cotton tolerance, since changes in cuticle concentrations were minimal. Cocklebur resistance to MSMA is not due to cuticle constituents; the wax changes are a secondary effect in response to herbicide application.

  20. Monosodium glutamate derived tricolor fluorescent carbon nanoparticles for cell-imaging application.

    PubMed

    Zheng, Nannan; Ding, Sha; Zhou, Xingping

    2016-06-01

    Fluorescent carbon nanoparticle (FCN) is a new type of carbon-based materials. Because of its wide raw material sources, excellent optical properties and good biocompatibility, FCN is getting more and more attentions. However, its synthesis from resources at low cost under mild conditions is still a challenge. Here we report a novel and simple method derived from monosodium glutamate carbonization to make tricolor fluorescent carbon nanoparticles with an average size below 10nm, a high yield up to 35.2% based on the carbon content in the resource, a long life-time of 3.71ns, and a high fluorescence quantum yield up to 51.5% by using quinine sulfate as the standard substance. We discovered that the fluorescent stability of the FCNs was very excellent under UV irradiation for hours in aqueous solutions of pH ranged from 2.0 to 9.0. The cell viability tested under a pretty high concentration of FCNs indicated their safety for biological applications. Based on their high fluorescence quantum efficiency and the advantages mentioned above, these FCNs were then used for cell imaging and exhibited a perfect performance under 3 kinds of excitation bands (UV, blue, and green lights). Thus, they can be practically applied to immune labeling and imaging in vivo in the near future. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Acquired flavor acceptance and intake facilitated by monosodium glutamate in humans.

    PubMed

    Yeomans, Martin R; Gould, Natalie J; Mobini, Sirous; Prescott, John

    2008-03-18

    Monosodium glutamate (MSG) is known to enhance liking for the flavor of savory foods, but whether associations between flavors and effects of MSG lead to changes in subsequent liking and intake for the flavor alone is unclear. To test this, 32 volunteers evaluated and consumed a novel savory soup with no added MSG before and after four training sessions where the same soup was consumed either unchanged (Control) or with added MSG. The addition of MSG during training increased both pleasantness and savory character of the soup and resulted in a larger increase in rated pleasantness of the soup in the MSG-trained relative to control condition when the soup was re-evaluated Post-training without MSG. There was also a significant increase in voluntary soup intake Post-training after the soup had been paired with MSG but not in the Control condition, and rated hunger increased more after tasting the soup Post-training in the MSG-trained but not Control condition. These findings demonstrate that co-experience of a savory flavor and MSG can result in increased subsequent liking and intake for the flavor in the absence of MSG, and possible explanations for how MSG reinforces learning are discussed.

  2. Monosodium glutamate-sensitive hypothalamic neurons contribute to the control of bone mass

    NASA Technical Reports Server (NTRS)

    Elefteriou, Florent; Takeda, Shu; Liu, Xiuyun; Armstrong, Dawna; Karsenty, Gerard

    2003-01-01

    Using chemical lesioning we previously identified hypothalamic neurons that are required for leptin antiosteogenic function. In the course of these studies we observed that destruction of neurons sensitive to monosodium glutamate (MSG) in arcuate nuclei did not affect bone mass. However MSG treatment leads to hypogonadism, a condition inducing bone loss. Therefore the normal bone mass of MSG-treated mice suggested that MSG-sensitive neurons may be implicated in the control of bone mass. To test this hypothesis we assessed bone resorption and bone formation parameters in MSG-treated mice. We show here that MSG-treated mice display the expected increase in bone resorption and that their normal bone mass is due to a concomitant increase in bone formation. Correction of MSG-induced hypogonadism by physiological doses of estradiol corrected the abnormal bone resorptive activity in MSG-treated mice and uncovered their high bone mass phenotype. Because neuropeptide Y (NPY) is highly expressed in MSG-sensitive neurons we tested whether NPY regulates bone formation. Surprisingly, NPY-deficient mice had a normal bone mass. This study reveals that distinct populations of hypothalamic neurons are involved in the control of bone mass and demonstrates that MSG-sensitive neurons control bone formation in a leptin-independent manner. It also indicates that NPY deficiency does not affect bone mass.

  3. Monosodium glutamate induces apoptosis in naive and memory human B cells.

    PubMed

    Jovic, Z; Veselinovic, M; Vasic, K; Stankovic-Djordjevic, D; Cekic, S; Milovanovic, M; Sarac, M

    2009-01-01

    The aim of this study was to establish the existence of mGluR7 in normal B lymphocytes and analyse the effect of monosodium glutamate (MSG) on B cell apoptosis in vitro. B cells were purified by magnetic cell sorting using anti-CD19-coupled magnetic beads. Cells (10(6)/ml) were cultured with increasing MSG concentrations (1-100 mM). Detection of apoptosis by flow cytometry was performed using the Annexin V-FITC/Propidium iodide (PI) apoptosis detection kit. Naïve and memory B cell population were identified by CD27 staining. Expression of GluRs was determined using PCR. Exposure to increasing MSG concentrations displayed dose dependent effect on B cell viability altogether, ranging from 35% with 100 mM up to 80% with 1 mM MSG. Moreover, the number of late apoptotic cells as well as necrotic cells was dose dependant. Both CD27- as well as CD27+ B cells were affected by MSG. Basal expression of GluRs7 was detected in unstimulated B cells. Glutamate induced apoptosis can be seen in memory as well as naive B cell population and is probably mediated through mGluR7, whose expression in B cells we also confirmed. Our study suggests a new possible mechanism of crosstalk between the nervous and the immune system through glutamate as a potential key mediator (Fig. 4, Ref. 27). Full Text (Free, PDF) www.bmj.sk.

  4. Calcium pyrophosphate and monosodium urate crystals in synovial fluid as a cause of pseudoeosinophilia.

    PubMed

    Robier, Christoph; Neubauer, Manfred; Quehenberger, Franz; Stettin, Mariana; Rainer, Franz

    2011-08-01

    Synovial fluid (SF) leukocytes can be counted microscopically in a Neubauer chamber or by automated procedures using haematology analysers. Knowledge of laboratory artefacts is crucial for the correct interpretation of results obtained using automated methods. SF pseudoeosinophilia has recently been described as a new artefact in patients with crystal-related arthropathies. We investigated whether pseudoeosinophilia of SF is restricted to crystal-related disorders, or if it may also occur in other arthropathies. We compared the percentages of eosinophils in 120 crystal containing SF samples with 185 crystal-free specimens using the Wilcoxon test. Crystal positive samples, determined by polarised microscopy, contained at least two monosodium urate or calcium pyrophosphate crystals per 10 high power fields (630× magnification). True SF eosinophilia was ruled out by microscopic examination of stained slides. Crystal positive samples had significantly higher percentages of eosinophils than the controls (p<0.0001). No significant differences between the two crystal types were found (p=0.693). Thus, pseudoeosinophilia was significantly correlated with the presence of crystals, and none of the distinct crystal types was more likely to be associated with pseudoeosinophilia. In this study, SF pseudoeosinophilia was confirmed as a crystal-related laboratory artefact which has to be considered in the interpretation of automated SF leukocyte differential counts.

  5. Phase-on-frequency characteristics of the magnetic field effect for studying the mechanism of the branching chemiluminescent reaction of luminol

    NASA Astrophysics Data System (ADS)

    Triebel, Michael M.; Morozov, Andrey K.; Totrov, Maxim M.; Zorinyants, George E.; Frankevich, Eugene L.

    1993-11-01

    The magnetic field effect (MFE) has successfully been applied for investigation of the mechanism of the branching chemiluminescent (ChL) reaction of luminol oxidation in aqueous solution in the presence of hydrogen peroxide. The magnetic field (MF) influenced the rate constant of recombination of luminol radicals, and hence changed the reaction yield. Amplitude modulated MF was used. A general approach to the description of the response of a radical reaction to an alternating magnetic field is made. A strong difference in frequency dependencies of the MFE in two competitive channels of light generation was revealed. The lifetime of luminol radicals (of the order of milliseconds) in an aqueous alkali solution has been measured using the phase shift of MFE.

  6. Development of chemiluminescence method for determination of 10-hydroxycamptothecin based on luminol-[Ag(HIO₆)₂]⁵⁻ reaction in alkaline solution.

    PubMed

    Sun, Hanwen; Chen, Peiyun; Shi, Shasha; Li, Liqing

    2011-01-01

    A novel chemiluminescence (CL) method was developed for the determination of 10-hydroxycamptothecin(HCPT) based on the CL reaction between [Ag(HIO₆)₂]⁵⁻ and luminol in alkaline solution. CL emission of Ag(III) complex-luminol in alkaline medium was very different from that in acidic medium. A possible mechanism of enhanced CL emission was suggested. The enhanced effect of HCPT on CL emission of the [Ag(HIO₆)₂]⁵⁻-luminol system was found. The enhanced degree of CL emission was proportional to HCPT concentration. The effect of the reaction conditions on CL emission was examined. Under optimal conditions, the limit of detection was 6.5 × 10⁻⁹ g mL⁻¹. The proposed method was applied for the determination of HCPT in real samples with the recoveries of 93.2-109% with the RSD of 1.7-3.3%.

  7. Highly luminescent S,N co-doped carbon quantum dots-sensitized chemiluminescence on luminol-H2 O2 system for the determination of ranitidine.

    PubMed

    Chen, Jianqiu; Shu, Juan; Chen, Jiao; Cao, Zhiran; Xiao, An; Yan, Zhengyu

    2017-05-01

    S,N co-doped carbon quantum dots (N,S-CQDs) with super high quantum yield (79%) were prepared by the hydrothermal method and characterized by transmission electron microscopy, photoluminescence, UV-Vis spectroscopy and Fourier transformed infrared spectroscopy. N,S-CQDs can enhance the chemiluminescence intensity of a luminol-H2 O2 system. The possible mechanism of the luminol-H2 O2 -(N,S-CQDs) was illustrated by using chemiluminescence, photoluminescence and ultraviolet analysis. Ranitidine can quench the chemiluminescence intensity of a luminol-H2 O2 -N,S-CQDs system. So, a novel flow-injection chemiluminescence method was designed to determine ranitidine within a linear range of 0.5-50 μg ml(-1) and a detection limit of 0.12 μg ml(-1) . The method shows promising application prospects. Copyright © 2016 John Wiley & Sons, Ltd.

  8. On the use of L-012, a luminol-based chemiluminescent probe, for detecting superoxide and identifying inhibitors of NADPH oxidase: A re-evaluation

    PubMed Central

    Zielonka, Jacek; Lambeth, J. David; Kalyanaraman, Balaraman

    2014-01-01

    L-012, a luminol-based chemiluminescent (CL) probe, is widely used in vitro and in vivo to detect NADPH oxidase (Nox)-derived superoxide (O2·−) and identify Nox inhibitors. Yet understanding of the free radical chemistry of L-012 probe is still lacking. We report that peroxidase and H2O2 induce superoxide dismutase (SOD)-sensitive, L-012-derived CL in the presence of oxygen. O2·− alone does not react with L-012 to emit luminescence. Self-generated O2·− during oxidation of L-012 and luminol-analogs artifactually induce CL inhibitable by SOD. These aspects make assays based on luminol analogs less than ideal for specific detection and identification of O2·− and NOX inhibitors. PMID:24080119

  9. On the use of L-012, a luminol-based chemiluminescent probe, for detecting superoxide and identifying inhibitors of NADPH oxidase: a reevaluation.

    PubMed

    Zielonka, Jacek; Lambeth, J David; Kalyanaraman, Balaraman

    2013-12-01

    L-012, a luminol-based chemiluminescent (CL) probe, is widely used in vitro and in vivo to detect NADPH oxidase (Nox)-derived superoxide (O2(*-)) and identify Nox inhibitors. Yet understanding of the free radical chemistry of the L-012 probe is still lacking. We report that peroxidase and H2O2 induce superoxide dismutase (SOD)-sensitive, L-012-derived CL in the presence of oxygen. O2(*-) alone does not react with L-012 to emit luminescence. Self-generated O2(*-) during oxidation of L-012 and luminol analogs artifactually induce CL inhibitable by SOD. These aspects make assays based on luminol analogs less than ideal for specific detection and identification of O2(*-) and NOX inhibitors.

  10. Trikatu, a herbal compound that suppresses monosodium urate crystal-induced inflammation in rats, an experimental model for acute gouty arthritis.

    PubMed

    Murunikkara, Vachana; Rasool, Mahaboobkhan

    2014-01-01

    Gout is an inflammatory joint disorder characterized by hyperuricaemia and precipitation of monosodium urate crystals in the joints. In the present study, we aimed to investigate the anti-inflammatory effect of trikatu, a herbal compound in monosodium urate crystal-induced inflammation in rats, an experimental model for acute gouty arthritis. Paw volume and levels/activities of lysosomal enzymes, lipid peroxidation, anti-oxidant status and histopathological examination of ankle joints were determined in control and monosodium urate crystal-induced rats. In addition, analgesic (acetic acid-induced writhing response), anti-pyretic (yeast-induced pyrexia) and gastric ulceration effects were tested. The levels of lysosomal enzymes, lipid peroxidation and paw volume were significantly increased, and anti-oxidant status was found to be reduced in monosodium urate crystal-induced rats, whereas the biochemical changes were reverted to near normal levels upon trikatu (1000 mg/kg b.wt) administration. The trikatu has also been found to exhibit significant analgesic and anti-pyretic effects with the absence of gastric damage. In conclusion, the present results clearly indicated that trikatu exert a potent anti-inflammatory effect against monosodium urate crystal-induced inflammation in rats in association with analgesic and anti-pyretic effects in the absence of gastrointestinal damage.

  11. Amplified cathodic electrochemiluminescence of luminol based on Pd and Pt nanoparticles and glucose oxidase decorated graphene as trace label for ultrasensitive detection of protein.

    PubMed

    Cao, Yaling; Yuan, Ruo; Chai, Yaqin; Liu, Huijing; Liao, Yuhong; Zhuo, Ying

    2013-09-15

    An ultrasensitive electrochemiluminescence (ECL) immunosensor was constructed for ultrasensitive detection of carcinoembryonic antigen (CEA) based on an amplified cathodic ECL of luminol at low potential. Firstly, Au nanoparticles (AuNPs) were electrodeposited onto single walled carbon nanotube-graphene composites (CNTs-Gra) coated glass carbon electrode (GCE) with enhanced surface area and good biocompatibility to capture primary antibody (Ab1) and then bind the antigen analytes. Secondly, Pd and Pt nanoparticles (Pd&PtNPs) decorated reduced graphene oxide (Pd&PtNPs@rGO) and glucose oxidase (GOD) labeled secondary antibody (Pd&PtNPs@ rGO-GOD-Ab2) could be captured onto the electrode surface by a sandwich immunoassay protocol to generate amplified cathodic ECL signals of luminol in the presence of glucose. The Pd&PtNPs@rGO composites and loaded GOD promoted luminol cathodic ECL response by efficiently catalyzing glucose to in-situ produce amount of hydrogen peroxide (H2O2) working as a coreactant of luminol. Then in turn Pd&PtNPs catalyzed H2O2 to generate various reactive oxygen species (ROSs), which accelerated the cathodic ECL reaction of luminol, enhanced the cathodic ECL intensity of luminol and improved the sensitivity of the immunosensor. The as-proposed ECL immunosensor exhibited sensitive response on the detection of CEA ranging from 0.0001 ng mL(-1) to 160 ng mL(-1) with a detection limit of 0.03 pg mL(-1) (S/N=3). Moreover, the stability, specificity, lifetime and reproducibility tests demonstrated the feasibility of the developed immunoassay, which can be further extended to the detection of other disease biomarkers. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Signal-on dual-potential electrochemiluminescence based on luminol-gold bifunctional nanoparticles for telomerase detection.

    PubMed

    Zhang, Huai-Rong; Wu, Mei-Sheng; Xu, Jing-Juan; Chen, Hong-Yuan

    2014-04-15

    Here, we report a novel type of signal-on dual-potential electrochemiluminescence (ECL) approach for telomerase detection based on bifunctionalized luminol-gold nanoparticles (L-Au NPs). In this approach, CdS nanocrystals (NCs) were first coated on glassy carbon electrode, and then thiol-modified telomerase primer was attached on CdS NCs via Cd-S bond. In the presence of telomerase and dNTPs, the primer could be extended. Telomerase primer would hybridize with its complementary DNA, and the extended part would hybridize with the capture DNA which was tagged with L-Au NPs. In the presence of coreactant H2O2, the L-Au NPs could not only enhance the ECL intensity of CdS NCs at -1.25 V (vs SCE) induced by the surface plasmon resonance (SPR) of Au NPs but also produce a new ECL signal at +0.45 V (vs SCE) that resulted from luminol in L-Au NPs. Both signals at two potentials increased with the increase of telomerase concentration. This method could be used to detect the telomerase from 100 to 9000 HL-60 cells and investigate the apoptosis of tumor cells. The ratio of the two signal increments (ΔECL(Luminol)/ΔECL(CdS NCs)), which showed a high consistency value for different numbers of cells, could be used to verify the reliability of tests. This dual-potential ECL strategy showed great promise in avoiding false positive or negative results in bioanalysis.

  13. Electrochemiluminescence of luminol enhanced by the synergetic catalysis of hemin and silver nanoparticles for sensitive protein detection.

    PubMed

    Jiang, Xinya; Chai, Yaqin; Wang, Haijun; Yuan, Ruo

    2014-04-15

    A novel and ultrasensitive electrochemiluminescence (ECL) immunosensor, which was based on the amplifying ECL of luminol by hemin-reduced graphene oxide (hemin-rGO) and Ag nanoparticles (AgNPs) decorated reduced graphene oxide (Ag-rGO), was constructed for the detection of carcinoembryonic antigen (CEA). For this proposed sandwich-type ECL immunosensor, Au nanoparticles electrodeposited (DpAu) onto hemin-rGO (DpAu/hemin-rGO) constructed the base of the immunosensor. DpAu had outstanding electrical conductivity to promote the electron transfer at the electrode interface and had good biocompatibility to load large amounts of primary antibody (Ab1), which provided an excellent platform for this immunosensor. Moreover, AgNPs and glucose oxidase (GOD) functionalized graphene labeled secondary antibody (Ag-rGO-Ab2-GOD) was designed as the signal probe for the sandwiched immunosensor. Not only did the hemin-rGO improve the electron transfer of the electrode surface, but hemin also further amplified the ECL signal of luminol in the presence of hydrogen peroxide (H2O2). With the aid of Ag-rGO-Ab2-GOD, enhanced signal was obtained by in situ generation of H2O2 and catalysis of AgNPs to ECL reaction of the luminol-H2O2 system. The as-prepared ECL immunosensor exhibited excellent analytical property for the detection of CEA in the range from 0.1 pg mL(-1) to 160 ng mL(-1) with a detection limit of 0.03 pg mL(-1) (SN(-1)=3). © 2013 Published by Elsevier B.V.

  14. Study of the oscillation and luminol chemiluminescence in the H 2O 2-KSCN-CuSO 4-NaOH system

    NASA Astrophysics Data System (ADS)

    Kiatisevi, Supavadee; Maisch, Steffen

    2010-10-01

    Oscillations in redox potential and chemiluminescence of the H 2O 2-KSCN-CuSO 4-NaOH system in the presence of luminol were examined. Parts of the mechanism proposed in the previous studies were evaluated by substitution of SCN - with CN -. The amplitude of the chemiluminescent oscillations was found to be strongly dependent on the initial luminol concentrations. In addition, the time-series ARMA (2;1)-analysis with Box-Jenkins algorithm were used to simulate the system and the result is well in accordance with the observed oscillations.

  15. Enhanced chemiluminescence of the luminol-hydrogen peroxide system by colloidal cupric oxide nanoparticles as peroxidase mimic.

    PubMed

    Chen, Wei; Hong, Lei; Liu, Ai-Lin; Liu, Jian-Qing; Lin, Xin-Hua; Xia, Xing-Hua

    2012-09-15

    As a peroxidase mimic, cupric oxide nanoparticles were found to enhance the chemiluminescence (CL) of luminol-H(2)O(2) system up to 400 folds. The CL spectra and radical scavengers were conducted to investigate the possible CL enhancement mechanism. It was suggested that the enhanced CL could be attributed to the peroxidase-like activity of CuO nanoparticles, which effectively catalyzed the decomposition of hydrogen peroxide into hydroxyl radicals. The effects of the reactant concentrations and some organic compounds were also investigated. The proposed method could be used as a sensitive detection tool for hydrogen peroxide and glucose.

  16. Chemiluminescence studies between aqueous phase synthesized mercaptosuccinic acid capped cadmium telluride quantum dots and luminol-H2O2

    NASA Astrophysics Data System (ADS)

    Kaviyarasan, Kulandaivelu; Anandan, Sambandam; Mangalaraja, Ramalinga Viswanathan; Asiri, Abdullah M.; Wu, Jerry J.

    2016-08-01

    Mercaptosuccinic acid capped Cadmium telluride quantum dots have been successfully synthesized via aqueous phase method. The products were well characterized by a number of analytical techniques, including FT-IR, XRD, HRTEM, and a corrected particle size analysis by the statistical treatment of several AFM measurements. Chemiluminescence experiments were performed to explore the resonance energy transfer between chemiluminescence donor (luminol-H2O2 system) and acceptor CdTe QDs. The combination of such donor and acceptor dramatically reduce the fluorescence while compared to pristine CdTe QDs without any exciting light source, which is due to the occurrence of chemiluminescence resonance energy transfer (CRET) processes.

  17. Natural cyclodextrins as efficient boosters of the chemiluminescence of luminol and isoluminol: exploration of potential applications.

    PubMed

    Maeztu, Raquel; Tardajos, Gloria; González-Gaitano, Gustavo

    2010-03-04

    The chemiluminescent oxidation of luminol (LUM) and isoluminol (ISOL) is notably enhanced, both in intensity and duration, in the presence of natural cyclodextrins (alpha-, beta-, gamma-CD). The experiments have considered some of the most widespread applications of these compounds: the determination of metal cations and the revealing of bloodstains by oxidation with hydrogen peroxide in alkaline solution in the presence of Co(II), Fe(III), human hemoglobin, and blood, in order to explore potential applications. The largest enhancement in the emitted intensity occurs for the reaction of LUM with Co(II) in the presence of beta-CD. The use of the more soluble gamma-CD permits to expand the range of concentration and obtain more intense emission, although soluble derivatives of the beta-CD (methyl, hydroxypropyl-beta-CD, and a soluble cross-linked epichlorhydrin polymer) do not improve the chemiluminescence (CL) yield. In the case of hemoglobin and diluted human blood, the CDs aid in producing more light but only at high concentration of CDs, with a more lasting luminescence, up to three times longer. The changes in CL when glucose is used instead, much lower than with any of the CDs, imply that the cyclic structure of these oligosaccharides plays a key factor in the boosting of the emission. The results are explained in terms of the binding between the luminescent intermediate of the reaction, 3-aminophthalate (3-AP) and the CD, rather than to the luminescent reactant itself. The association constants obtained by steady-state fluorescence by assuming 1:1 stoichiometries reveal that the most stable association occurs between beta-CD and the intermediate, in accordance with the trend in the chemiluminescence. The topology of the complex deduced via ROESY experiments confirms a shallow inclusion of the double-charged intermediate by the primary rim of the CD, which accounts for the low stability of the complexes.

  18. The new approach for captopril detection employing triangular gold nanoparticles-catalyzed luminol chemiluminescence.

    PubMed

    Chen, Qingshuo; Bai, Shouli; Lu, Chao

    2012-01-30

    In this work, we utilize the triangular gold nanoparticles (AuNPs) prepared by trisodium citrate reduction of HAuCl(4) in presence of nonionic fluorosurfactant (FSN) as a novel chemiluminescence (CL) probe for the determination of captopril. Captopril can induce a sharp decrease in CL intensity from the triangular AuNPs-catalyzed luminol system. Under the selected experimental conditions, a linear relationship was obtained between the logarithm of CL intensity and the logarithm of concentration of captopril in the range of 23.0-920 nM, and the detection limit at a signal-to-noise ratio of 3 for captopril was 4.6 nM. The as-prepared triangular AuNPs were easier to synthesize, stable at a wider pH range and high ionic strength, and exhibited a high selectivity and an excellent sensitivity toward captopril. The applicability of the proposed method has been validated by determining captopril in commercial pharmaceutical formulations and human urine samples with satisfactory results. The recoveries for captopril in spiked samples were found to be between 95.0% and 103.5%. The method shows promise for routine control analysis of pharmaceutical preparations and human urine samples. Moreover, based on the CL spectra, UV-vis spectra and transmission electron microscope (TEM) measurements, a possible CL mechanism was proposed. The mechanism of high selectivity toward captopril is supposed to originate from the tight binding of the sulphydryl groups of captopril to the active site of the as-prepared triangular AuNPs, leading to oxygen-related radicals cannot easily be generated from H(2)O(2) on the surface of triangular AuNPs.

  19. RADIUM AND THORIUM SORPTION BY MONOSODIUM TITANATE (MST) AND MODIFIED MST (mMST)

    SciTech Connect

    Taylor-Pashow, K.; Hobbs, D.

    2012-02-15

    A series of tests were planned to examine the removal of Ra and Th by monosodium titanate (MST) and modified monosodium titanate (mMST). Simulated waste solutions were prepared containing Ra and Th, along with Sr, Np, Pu, and U. Following simulant preparation the simulants were filtered through 0.45-m filters. Analysis of the simulants indicated no Th in the filtered solution. This is due to the very low solubility of Th in alkaline solutions. Based on the reported detection limits for {sup 228}Th by gamma analyses, the solubility of Th in the simulant solutions is < 3.0E-10 g/L or < 1.3E-12 M. Therefore, data could not be obtained regarding the removal of Th by MST and mMST; however, testing proceeded to examine the removal of Ra. Sorption testing indicated that Ra, like Sr, is very rapidly removed from solution by both MST and mMST. The Ra concentration in solution fell below the method detection limit (MDL) within 30 minutes of contact with MST, and within 2 hours of contact with mMST, when tested at 25 C using a 5.6 M Na simulant. Additional testing examined the effects of ionic strength and temperature on the MST and mMST performance. Results from these tests showed that the majority of samples still reached a Ra concentration below the MDL, indicating excellent removal. For the highest ionic strength solution (6.6 M Na), there did appear to be a slight decrease in the Ra removal by mMST, as indicated by a larger number of samples just above the MDL. The effect of temperature on {sup 226}Ra removal is indeterminate for either MST or mMST in the temperature range (25-60 C) and concentrations studied since the final soluble concentration of Ra remained at or below the detection limits for all tests. Desorption testing was also performed using decontaminated salt solution (DSS) diluted to sodium concentrations of 2 M and 0.5 M, to represent the intermediate and final stages of washing. Results from these tests indicated no desorption of any sorbents, with the

  20. Dietary supplementation with monosodium glutamate is safe and improves growth performance in postweaning pigs.

    PubMed

    Rezaei, Reza; Knabe, Darrell A; Tekwe, Carmen D; Dahanayaka, Sudath; Ficken, Martin D; Fielder, Susan E; Eide, Sarah J; Lovering, Sandra L; Wu, Guoyao

    2013-03-01

    Dietary intake of glutamate by postweaning pigs is markedly reduced due to low feed consumption. This study was conducted to determine the safety and efficacy of dietary supplementation with monosodium glutamate (MSG) in postweaning pigs. Piglets were weaned at 21 days of age to a corn and soybean meal-based diet supplemented with 0, 0.5, 1, 2, and 4 % MSG (n = 25/group). MSG was added to the basal diet at the expense of cornstarch. At 42 days of age (21 days after weaning), blood samples (10 mL) were obtained from the jugular vein of 25 pigs/group at 1 and 4 h after feeding for hematological and clinical chemistry tests; thereafter, pigs (n = 6/group) were euthanized to obtain tissues for histopathological examinations. Feed intake was not affected by dietary supplementation with 0-2 % MSG and was 15 % lower in pigs supplemented with 4 % MSG compared with the 0 % MSG group. Compared with the control, dietary supplementation with 1, 2 and 4 % MSG dose-dependently increased plasma concentrations of glutamate, glutamine, and other amino acids (including lysine, methionine, phenylalanine and leucine), daily weight gain, and feed efficiency in postweaning pigs. At day 7 postweaning, dietary supplementation with 1-4 % MSG also increased jejunal villus height, DNA content, and antioxidative capacity. The MSG supplementation dose-dependently reduced the incidence of diarrhea during the first week after weaning. All variables in standard hematology and clinical chemistry tests, as well as gross and microscopic structures, did not differ among the five groups of pigs. These results indicate that dietary supplementation with up to 4 % MSG is safe and improves growth performance in postweaning pigs.

  1. Supplementing monosodium glutamate to partial enteral nutrition slows gastric emptying in preterm pigs(1-3).

    PubMed

    Bauchart-Thevret, Caroline; Stoll, Barbara; Benight, Nancy M; Olutoye, Oluyinka; Lazar, David; Burrin, Douglas G

    2013-05-01

    Emerging evidence suggests that free glutamate may play a functional role in modulating gastroduodenal motor function. We hypothesized that supplementing monosodium glutamate (MSG) to partial enteral nutrition stimulates gastric emptying in preterm pigs. Ten-day-old preterm, parenterally fed pigs received partial enteral nutrition (25%) as milk-based formula supplemented with MSG at 0, 1.7, 3.0, and 4.3 times the basal protein-bound glutamate intake (468 mg·kg(-1)·d(-1)) from d 4 to 8 of life (n = 5-8). Whole-body respiratory calorimetry and (13)C-octanoic acid breath tests were performed on d 4, 6, and 8. Body weight gain, stomach and intestinal weights, and arterial plasma glutamate and glutamine concentrations were not different among the MSG groups. Arterial plasma glutamate concentrations were significantly higher at birth than after 8 d of partial enteral nutrition. Also at d 8, the significant portal-arterial concentration difference in plasma glutamate was substantial (∼500 μmol/L) among all treatment groups, suggesting that there was substantial net intestinal glutamate absorption in preterm pigs. MSG supplementation dose-dependently increased gastric emptying time and decreased breath (13)CO2 enrichments, (13)CO2 production, percentage of (13)CO2 recovery/h, and cumulative percentage recovery of (13)C-octanoic acid. Circulating glucagon-like peptide-2 (GLP-2) concentration was significantly increased by MSG but was not associated with an increase in intestinal mucosal growth. In contrast to our hypothesis, our results suggest that adding MSG to partial enteral nutrition slows the gastric emptying rate, which may be associated with an inhibitory effect of increased circulating GLP-2.

  2. Monosodium glutamate intake increases hemoglobin level over 5 years among Chinese adults.

    PubMed

    Shi, Zumin; Yuan, Baojun; Taylor, Anne W; Dal Grande, Eleonora; Wittert, Gary A

    2012-09-01

    The aim of this analysis was to determine the relationship between monosodium glutamate (MSG) intake and change in hemoglobin (Hb) levels and the risk of anemia over 5 years in 1197 Chinese men and women who participated in the Jiangsu Nutrition Study (JIN). MSG intake and Hb were quantitatively assessed in 2002 and followed up in 2007. Diet and lifestyle factors were assessed at both time points. There was a positive association between MSG intake and increase in Hb among men but not women. In the multivariate model adjusting for demographic and lifestyle factors as well as baseline dietary pattern, the beta values and 95% confidence interval for Hb changes across quartiles of MSG intake were 0, 0.67(0.04-1.29), 0.99(0.38-1.60), 0.73(0.13-1.34) among men (p for trend 0.091); 0, -0.01(-0.45-0.43), 0.23(-0.25-0.71), and -0.45(-0.96-0.05) among women (p for trend 0.087). Among anemic participants at baseline, there was a significant inverse association between MSG intake and the risk of anemia at follow-up. Comparing extreme quartiles of MSG intake among those anemic at baseline, the relative risk for persistent anemia at follow-up was 0.49 (95% CI: 0.28-0.86, p < 0.01). The association was independent of dietary patterns and lifestyle factors. A dose-response relationship between MSG intake and increase in Hb levels among anemic participants was seen. MSG intake may have independent Hb-increasing effects, especially among men and those anemic at baseline.

  3. Therapeutic effects of sesame oil on monosodium urate crystal-induced acute inflammatory response in rats.

    PubMed

    Hsu, Dur-Zong; Chen, Si-Jin; Chu, Pei-Yi; Liu, Ming-Yie

    2013-01-01

    Sesame oil has been used in traditional Taiwanese medicine to relieve the inflammatory pain in people with joint inflammation, toothache, scrapes, and cuts. However, scientific evidence related to the effectiveness or action mechanism of sesame oil on relief of pain and inflammation has not been examined experimentally. Here, we investigated the therapeutic effect of sesame oil on monosodium urate monohydrate (MSU) crystal-induced acute inflammatory response in rats. Air pouch, a pseudosynovial cavity, was established by injecting 24 mL of filtered sterile air subcutaneously in the backs of the rats. At day 0, inflammation in air pouch was induced by injecting MSU crystal (5 mg/rat, suspended in sterilized phosphate buffered saline, pH 7.4), while sesame oil (0, 1, 2, or 4 mL/kg, orally) was given 6 h after MSU crystal injection. Parameters in lavage and skin tissue from the air pouches were assessed 6 h after sesame oil was given. Sesame oil decreased MSU crystal-induced total cell counts, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 levels in lavage and pouch tissue. Sesame oil significantly decreased leukocyte and neutrophil counts in lavage compared with MSU crystal alone group. Sesame oil decreased activated mast cell counts in skin tissue in MSU crystal-treated rats. Sesame oil significantly decreased nuclear factor (NF)-κB activity and IL-4 level in isolated mast cells from rats treated with MSU crystal. Furthermore, sesame oil decreased lavage complement proteins C3a and C5a levels in MSU crystal-treated rats. In conclusion, sesame oil shows a potent therapeutic effect against MSU crystal-induced acute inflammatory response in rats.

  4. Using monosodium glutamate to initiate ethanol self-administration in inbred mouse strains.

    PubMed

    McCool, Brian A; Chappell, Ann M

    2012-01-01

    Voluntary oral ethanol consumption in rodents is generally limited by strong taste-aversion in these species. Historically, this has been overcome by combining ethanol with a sweetener, typically sucrose or saccharine, and then slowly 'fading' away the sweetener. While useful in most instances, this approach has not proven as successful for some inbred strains of mice (e.g. DBA/2J) despite consistent evidence in the literature that these same strains express strong conditioned place preference for intraperitoneal- or intragastric-administered ethanol. Importantly, DBA/2J mice express a polymorphism in a 'sweet' taste receptor subunit gene that reduces the potency of sweet substances in these mice. We hypothesized that the presence of this polymorphism might help explain the contrasting behavioral findings of weak voluntary oral ethanol consumption following sucrose-fade yet robust conditioned place preference for ethanol in this strain. To test this, we compared ethanol consumption initiated by either a 'traditional' sucrose-fade or a fade from an alternative tastant, monosodium glutamate (MSG). We found that in both C57BL/6J and DBA/2J mice, the MSG-fade produced robust increases in home cage ethanol consumption relative to the traditional sucrose-fade. This increased ethanol intake following MSG-fade was evident across a range of ethanol concentrations. Our findings suggest the potential utility of the MSG-fade to establish stable voluntary oral ethanol consumption in mice, particularly ethanol 'non-preferring' strains such as DBA/2J and lend additional support to the notion that ethanol consumption in DBA/2J mice is limited by pronounced taste aversion.

  5. Arsenic Retention in Foliage and Soil after Monosodium Methyl Arsenate (MSMA) Application to Turfgrass.

    PubMed

    Matteson, Audrey R; Gannon, Travis W; Jeffries, Matthew D; Haines, Stephanie; Lewis, Dustin F; Polizzotto, Matthew L

    2014-01-01

    Monosodium methyl arsenate (MSMA) is a commonly used herbicide for weed control in turfgrass systems. There is concern that arsenic from applied MSMA could leach to groundwater or run off into surface water, thereby threatening human and ecosystem health. The USEPA has proposed a phase-out of the herbicide but is seeking additional research about the toxicity and environmental impacts of MSMA before establishing a final ruling. Little research has systematically investigated MSMA in field-based settings; instead, risks have been inferred from isolated field measurements or model-system studies. Accordingly, the overall goal of this study was to quantify the fate of arsenic after MSMA application to a managed turfgrass system. After MSMA application to turfgrass-covered and bareground lysimeters, the majority of arsenic was retained in turfgrass foliage and soils throughout year-long experiments, with 50 to 101% of the applied arsenic recovered in turfgrass systems and 55 to 66% recovered in bareground systems. Dissolved arsenic concentrations from 76.2-cm-depth pore water in the MSMA-treated soils were consistently <2 μg L, indistinguishable from background concentrations. As measured by adsorption isotherm experiments, MSMA retention by the sandy soil from our field site was markedly less than retention by a washed sand and a clay loam. Collectively, these results suggest that under aerobic conditions, minimal arsenic leaching to groundwater would occur after a typical application of MSMA to turfgrass. However, repeated MSMA application may pose environmental risks. Additional work is needed to examine arsenic cycling near the soil surface and to define arsenic speciation changes under different soil conditions.

  6. Role of TRPV1 in nociception and edema induced by monosodium urate crystals in rats.

    PubMed

    Hoffmeister, Carin; Trevisan, Gabriela; Rossato, Mateus Fortes; de Oliveira, Sara Marchesan; Gomez, Marcus Vinícius; Ferreira, Juliano

    2011-08-01

    Gout is characterized by the deposition of monosodium urate (MSU) crystals. Despite being one of the most painful forms of arthritis, gout and the mechanisms responsible for its acute attacks are poorly understood. In the present study, we found that MSU caused dose-related nociception (ED(50) [ie, the necessary dose of MSU to elicit 50% of the response relative to the control value]=0.04 [95% confidence interval 0.01-0.11]mg/paw) and edema (ED(50)=0.08 [95% confidence interval 0.04-0.16]mg/paw) when injected into the hind paw of rats. Treatment with the selective TRPV1 receptor (also known as capsaicin receptor and vanilloid receptor-1) antagonists SB366791 or AMG9810 largely prevented nociceptive and edematogenic responses to MSU. Moreover, the desensitization of capsaicin-sensitive afferent fibers as well as pretreatment with the tachykinin NK(1) receptor antagonist RP 67580 also significantly prevented MSU-induced nociception and edema. Once MSU was found to induce mast cell stimulation, we investigated the participation of these cells on MSU effects. Prior degranulation of mast cells by repeated treatment with the compound 48/80 decreased MSU-induced nociception and edema or histamine and serotonin levels in the injected tissue. Moreover, pretreatment with the mast cell membrane stabilizer cromolyn effectively prevented nociceptive and edematogenic responses to MSU. MSU induced a release of histamine, serotonin, and tryptase in the injected tissue, confirming mast cell degranulation. Furthermore, the antagonism of histaminergic H1 and serotoninergic receptors decreased the edema, but not the nociception of MSU. Finally, the prevention of the tryptase activity was capable of largely reducing both MSU-induced nociception and edema. Collectively, the present findings demonstrate that MSU produces nociceptive and edematogenic responses mediated by TRPV1 receptor activation and mast cell degranulation. Copyright © 2011 International Association for the Study of

  7. Ursodeoxycholic Acid ameliorates pain severity and cartilage degeneration in monosodium iodoacetate-induced osteoarthritis in rats.

    PubMed

    Moon, Su-Jin; Jeong, Jeong-Hee; Jhun, Joo Yeon; Yang, Eun Ji; Min, Jun-Ki; Choi, Jong Young; Cho, Mi-La

    2014-02-01

    Osteoarthritis (OA) is a degenerative joint disease characterized by a progressive loss of cartilage. And, increased oxidative stress plays a relevant role in the pathogenesis of OA. Ursodeoxycholic acid (UDCA) is a used drug for liver diseases known for its free radical-scavenging property. The objectives of this study were to investigate the in vivo effects of UDCA on pain severity and cartilage degeneration using an experimental OA model and to explore its mode of actions. OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration UDCA was initiated on the day of MIA injection. Limb nociception was assessed by measuring the paw withdrawal latency and threshold. Samples were analyzed macroscopically and histologically. Immunohistochemistry was used to investigate the expression of interleukin-1β (IL-1β), IL-6, nitrotyrosine and inducible nitric oxide synthase (iNOS) in knee joints. UDCA showed an antinociceptive property and attenuated cartilage degeneration. OA rats given oral UDCA significantly exhibited a decreased number of osteoclasts in subchondral bone legion compared with the vehicle-treated OA group. UDCA reduced the expression of IL-1β, IL-6, nitrotyrosine and iNOS in articular cartilage. UDCA treatment significantly attenuated the mRNA expression of matrix metalloproteinase-3 (MMP-3), -13, and ADAMTS5 in IL-1β-stimulated human OA chondrocytes. These results show the inhibitory effects of UDCA on pain production and cartilage degeneration in experimentally induced OA. The chondroprotective properties of UDCA were achieved by suppressing oxidative damage and inhibiting catabolic factors that are implicated in the pathogenesis of cartilage damage in OA.

  8. Spinal neuropeptide modulation, functional assessment and cartilage lesions in a monosodium iodoacetate rat model of osteoarthritis.

    PubMed

    Otis, Colombe; Guillot, Martin; Moreau, Maxim; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Beaudry, Francis; Troncy, Eric

    2017-04-24

    Characterising the temporal evolution of changes observed in pain functional assessment, spinal neuropeptides and cartilage lesions of the joint after chemical osteoarthritis (OA) induction in rats. On day (D) 0, OA was induced by an IA injection of monosodium iodoacetate (MIA). Rats receiving 2mg MIA were temporally assessed at D3, D7, D14 and D21 for the total spinal cord concentration of substance P (SP), calcitonin gene related-peptide (CGRP), bradykinin (BK) and somatostatin (STT), and for severity of cartilage lesions. At D21, the same outcomes were compared with the IA 1mg MIA, IA 2mg MIA associated with punctual IA injection of lidocaine at D7, D14 and D21, sham (sterile saline) and naïve groups. Tactile allodynia was sequentially assessed using a von Frey anaesthesiometer. Non-parametric and mixed models were applied for statistical analysis. Tactile allodynia developed in the 2mg MIA group as soon as D3 and was maintained up to D21. Punctual IA treatment with lidocaine counteracted it at D7 and D14. Compared to naïve, [STT], [BK] and [CGRP] reached a maximum as early as D7, which plateaued up to D21. For [SP], the increase was delayed up to D14 and maintained at D21. No difference in levels of neuropeptides was observed between MIA doses, except for higher [STT] in the 2mg MIA group (P=0.029). Neuropeptides SP and BK were responsive to lidocaine treatment. The increase in severity of cartilage lesions was significant only in the 2mg MIA groups (P=0.01). In the MIA OA pain model, neuropeptide modulation appears early, and confirms the central nervous system to be an attractive target for OA pain quantification. The relationship of neuropeptide release with severity of cartilage lesions and functional assessment are promising and need further validation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Taste sensitivity for monosodium glutamate and an increased liking of dietary protein.

    PubMed

    Luscombe-Marsh, Natalie D; Smeets, Astrid J P G; Westerterp-Plantenga, Margriet S

    2008-04-01

    The aim of the present study was to determine individuals' taste threshold for monosodium glutamate (MSG) alone and in combination with inosine 5'-monophosphate (IMP-5) and to examine if this threshold was related to an increase in sensory properties (including pleasantness of taste) and/or to one's preference for dietary protein over carbohydrate and fat. Using the triangle tasting method, the taste threshold was determined for thirty-six women and twenty-four men. Thresholds varied from zero to infinite as determined using a clear soup with added MSG in the concentration range of 0.1 to 0.8 % (w/w) MSG. Subjects rated fourteen sensory properties of the soup and also their 'liking', 'eating frequency' and 'preference' of twenty-two common high-protein, high-carbohydrate and high-fat food items. The taste threshold (and therefore sensitivity) of MSG was lowered from 0.33 (sem 0.24) to 0.26 (sem 0.22) % MSG when 0.25 % (w/w) IMP-5 was added. None of the sensory properties assessed was associated with the taste threshold of MSG +/- 0.25 % IMP-5 in the overall study population. However, the taste descriptor 'meatiness' was associated with the threshold data for individuals who could taste concentrations of

  10. Factors influencing the crystallization of monosodium urate: a systematic literature review.

    PubMed

    Chhana, Ashika; Lee, Gerald; Dalbeth, Nicola

    2015-10-14

    Gout is a chronic disease of monosodium urate (MSU) crystal deposition. Although hyperuricaemia is the central risk factor for development of gout, not all people with hyperuricaemia have subclinical MSU crystal deposition or indeed, symptomatic disease. The aim of this systematic literature review was to identify factors that contribute to MSU crystallization. A search was conducted of the electronic databases PubMed, Science Direct and Scopus. Articles were included if they contained original data related to MSU crystallization. The methods and results were summarized and categorized into articles describing at least one of the three key steps in MSU crystallization (reduced urate solubility, nucleation and growth). A total of 2175 articles were initially identified in our systematic search with 35 of these articles included in the final analysis. Elevated urate concentration was identified as a central factor driving all three stages of MSU crystallization. Factors that were found to consistently reduce urate solubility were reduced temperatures, pH 7-9 and various ions including sodium ions. Connective tissue factors including bovine cartilage homogenates and healthy human synovial fluid and serum all enhanced urate solubility. MSU nucleation was found to be increased by a number of factors, including sodium ions, uric acid binding antibodies, and synovial fluid or serum from patients with gout. Other than elevated urate concentrations, no other specific factors were identified as promoters of MSU crystal growth. Increased urate concentration is the key factor required at each stage of MSU crystallization. Different proteins and factors within connective tissues may promote MSU crystallization and may be important for determining the sites at which MSU crystallization occurs in the presence of elevated urate concentrations.

  11. Doliroside A attenuates monosodium urate crystals-induced inflammation by targeting NLRP3 inflammasome.

    PubMed

    Wei, Han; Hu, Chao; Xie, Jinbo; Yang, Chao; Zhao, Yue; Guo, Yaqi; Mei, Zhinan; Chen, Lvyi; Lan, Zhou

    2014-10-05

    Our previous study demonstrates that Dolichos falcata Klein (DF) ameliorates the gouty arthritis induced by monosodium urate (MSU) crystals, and one of the active components, doliroside A, contributed to the anti-gouty arthritis effect of DF according to the in vitro study. However, there is still little known about the potential beneficial effects and possible mechanism of action of doliroside A on gouty arthritis. Here, we investigated the underlying mechanism of action of doliroside A in vitro and the anti-inflammatory effects of doliroside A in vivo. Bone-marrow-derived macrophages were treated with doliroside A before or after lipopolysaccharide (LPS) and then stimulated with MSU crystals, nigericin and adenosine triphosphate (ATP). The expressions of proteins related to activation of nucleotide-binding domain and leucine-rich repeat containing protein 3 (NLRP3) inflammasome were analyzed. The results manifested that doliroside A (15, 30, 45 and 60 μM) suppressed both LPS-induced priming and inflammasome activation in macrophages. Moreover, doliroside A was administered to the rats treated by MSU crystals. The results demonstrated that doliroside A (10, 20 and 40 mg/kg) ameliorated the symptoms of gouty arthritis, decreased the levels of pro-inflammatory cytokines, and inhibited the expressions of caspase-1 and pro-interleukin-1β (pro-IL-1β) proteins in MSU crystals-treated rats. These findings indicate that doliroside A exhibits a prominent effect on ameliorating gouty arthritis induced by MSU crystals. The action of doliroside A on gouty arthritis exerts via inhibiting the activation of caspase-1 and IL-1β secretion by affecting both LPS-induced priming and inflammasome activation. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Prevalence of monosodium urate deposits in a population of rheumatoid arthritis patients with hyperuricemia.

    PubMed

    Petsch, Christina; Araujo, Elizabeth G; Englbrecht, Matthias; Bayat, Sara; Cavallaro, Alexander; Hueber, Axel J; Lell, Michael; Schett, Georg; Manger, Bernhard; Rech, Juergen

    2016-06-01

    To investigate the prevalence of monosodium urate (MSU) crystal deposits, indicative for gout, in a population of rheumatoid arthritis (RA) patients with concomitant hyperuricemia and to analyze the clinical and disease-specific characteristics of RA patients who exhibit MSU crystal deposits. Overall, 100 consecutive patients with the diagnosis of RA and a serum urate level above 6mg/dl underwent dual energy computed tomography (DECT) of both feet and hands to search for MSU crystals in a prospective study between October 2011 and July 2013. Presence and extent of MSU crystal deposits on DECT was assessed by automated volume measurement. Demographic and disease-specific characteristics were recorded and included into two logistic regression models to test for the factors associated with MSU crystal deposits in RA. Hyperuricemic RA patients were mostly male (55%), over 60 years of age (63 ± 11 years), had established disease (8.7 ± 10.5 years) and a mean disease activity score 28 (DAS 28) of 3.2. In total, 20 out of 100 patients displayed MSU crystal deposits in DECT. Interestingly, the majority (70%) of the RA patients positive for MSU crystal deposits were seronegative RA patients. Hence, every third seronegative RA patient had MSU crystal deposits. According to logistic regression model analysis, seronegative status correlated positively with presence of urate deposits (p = 0.019). These data show that a considerable number of RA patients display periarticular MSU crystal deposits. Seronegative patients were shown to be predominantly affected with every third patient being positive for urate deposits. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Sodium azide as a specific quencher of singlet oxygen during chemiluminescent detection by luminol and Cypridina luciferin analogues.

    PubMed

    Bancirova, Martina

    2011-01-01

    Reactive oxygen species (ROS) are presently thought to play important role in an increasing number of the physiological and pathological processes in living organisms. Various chemiluminescent (CL) compounds have been studied in order to find suitable and specific probes for the detection of particular ROS species. The CL of luminol is known to be non-specific and can be induced by various oxidants. Two Cypridina luciferin analogues, CLA and MCLA, have been used for the detection of ROS in vivo. CLAs are thought to emit light only when reacting with superoxide and singlet oxygen. It is possible to distinguish the particular ROS by using a specific quencher or scavenger, e.g. superoxide dismutase (SOD) or sodium azide (NaN(3)). The CL reactions of luminol (3-aminophthalhydrazide), CLA [2-methyl-6-phenyl-3,7-dihydroimidazo(1,2α) pyrazin-3-one] and MCLA [2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo(1,2α) pyrazin-3-one] were studied in three hydrogen peroxide decomposition systems (H(2)O(2)-HRP; H(2)O(2)-CuSO(4); and H(2)O(2)-NaOCl). The measurements were carried out in phosphate buffer, pH 7.4, at 25°C, using a luminometer (Fluoroskan Ascent FL and Sirius C). NaN(3) was used as the specific quencher of singlet oxygen. The results demonstrate that the proclaimed specificity of the CL of Cypridina luciferin analogues towards singlet oxygen has to be discussed.

  14. Flow-injection chemiluminescence determination of phentolamine based on its enhancing effect on the luminol-potassium ferricyanide system.

    PubMed

    Huang, Yuming; Liu, Weibing

    2005-07-01

    It was found that the light emission produced by the oxidation of luminol by potassium ferricyanide in the basic medium was enhanced by phentolamine, a drug recently used to treatment of male and female sexual dysfunction. The optimum conditions for this chemiluminescent reaction were studied in detail by a flow-injection system. A new, simple and rapid method has been developed under the optimum conditions for determination of phentolamine. This method has the advantages of high sensitivity, good reproducibility and low detection limit. On the basis of investigation of chemiluminescent, fluorescent and UV spectra of phentolamine in basic solution containing potassium ferricyanide and luminol, a possible mechanism of this reaction was proposed. In the optimum conditions, CL intensities are proportional to concentrations of the phentolamine in the 0.01-1 microg/mL range. The limit of detection is 3.0 ng/mL for phentolamine. The method has been applied to the determination of phentolamine in the commercial preparations, synthetic samples and biological fluids with satisfactory results.

  15. A discrepancy in superoxide scavenging activity between the ESR-spin trapping method and the luminol chemiluminescence method.

    PubMed

    Sato, Emiko; Niwano, Yoshimi; Mokudai, Takayuki; Kohno, Masahiro; Matsuyama, Yukihiko; Kim, Daekyung; Oda, Tatsuya

    2007-06-01

    In a previous study of ours, the superoxide scavenging activity of aqueous extracts from dinophycean red tide flagellates was detected by an electron spin resonance (ESR)-spin trapping method, but not by an L-012 (luminol analog)-dependent chemiluminescence (CL) method. To investigate the discrepancy between the two methods, the effect of ferric-protein complexes on superoxide scavenging activity was examined. The reduced signal intensity of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO)-OOH due to superoxide dismutase (SOD) did not change with the addition of horseradish peroxidase (HRP), while the reduced CL response due to SOD was restored by the addition of different concentrations of HRP. Since HRP is a ferric-protein complex, the effects of other ferric-protein complexes, catalase and hemoglobin, on the reduced CL response due to SOD were examined, and similar results were obtained. As is the case with SOD, the reduced CL response activity due to an aqueous extract from a raphidophycean red tide flagellate, Chattonella ovata, was also enhanced by HRP, catalase, and hemoglobin. ESR spectra analyzed at 77 K indicated that aqueous extracts of Gymnodinium impudicum and Alexandrium affine, both of which are dinophycean red tide flagellates, contained a ferric-protein complex, and that an extract of C. ovata did not. These results suggest that the presence of such a ferric-protein complex is a causative factor in the discrepancy between the ESR and luminol CL methods when determining superoxide scavenging activity.

  16. Short-Time-Response measurements of nitrogen dioxide and peroxyacetyl nitrate by fast capillary gas chromatography with luminol detection.

    SciTech Connect

    Marley, N. A.; Gaffney, J. S.; Drayton, P. J.

    2000-12-07

    The interaction of hydrocarbons and nitrogen oxides in sunlight to produce photochemical smog has been well studied over the years. In the past, the workhorse for the measurement of NO{sub 2}and NO was the chemiluminescent reaction with ozone. This method has detection limits of approximately 0.5 ppb in most commercial instruments, but it cannot detect NO{sub 2} directly; the instrument detects NO and uses hot catalytic surfaces to decompose all other nitrogen oxides (including NO{sub 2}) to NO for detection (l). The main problem with the method is the inherent difficulty in detecting excited NO{sub 2}, which emits over a broad region beginning at approximately 660 nm and has a maximum at 1270 nm, thus requiring a red-shifted photomultiplier for detection. The use of luminol for direct chemiluminescent detection of NO{sub 2} was demonstrated to have greater inherent sensitivity (detection limits of 5 ppt) than the indirect ozone chemiluminescence detection (2). In the luminol system, a gas-liquid reaction leads to light emission with a maximum at approximately 425 nm, at the maximum sensitivity for most photomultiplier tubes. This emission is responsible for the increased detection sensitivities. The biggest problem with this method for direct measurement of NO{sub 2} has been interference due to other soluble oxidants, particularly peroxyacyl nitrates (PANs).

  17. Determination of 2-methoxyestradiol by chemiluminescence based on luminol-KMnO4-CdTe quantum dots system

    NASA Astrophysics Data System (ADS)

    Du, Bin; Wang, Tiantian; Han, Shuping; Cao, Xiaohui; Qu, Tiantian; Zhao, Feifei; Guo, Xinhong; Yao, Hanchun

    2015-02-01

    In this study, water-soluble CdTe quantum-dots (QDs) capped with glutathione (GSH) was synthesized. It was found that CdTe QDs could greatly enhance the chemiluminescence (CL) emission from the luminol-KMnO4 system in alkaline medium, and 4 nm CdTe QDs was used as catalysts to enhance the reaction sensitivity. The CL intensity of CdTe QDs-luminol-KMnO4 was strongly inhibited in the presence of 2-methoxyestradiol (2-ME) and the relative CL intensity was in linear correlation with the concentration of 2-ME. Based on this inhibition, a novel CL method with a lower detection limit and wider linear range was developed for the determination of 2-ME. The detection limit of plasma samples was 3.07 × 10-10 g mL-1 with a relative standard deviation of 0.24% for 8.0 × 10-9 g mL-1 2-ME. The method was successfully applied for determination of 2-ME in plasma samples. The possible CL reaction mechanism was also discussed briefly.

  18. Determination of 2-methoxyestradiol by chemiluminescence based on luminol-KMnO4-CdTe quantum dots system.

    PubMed

    Du, Bin; Wang, Tiantian; Han, Shuping; Cao, Xiaohui; Qu, Tiantian; Zhao, Feifei; Guo, Xinhong; Yao, Hanchun

    2015-02-05

    In this study, water-soluble CdTe quantum-dots (QDs) capped with glutathione (GSH) was synthesized. It was found that CdTe QDs could greatly enhance the chemiluminescence (CL) emission from the luminol-KMnO4 system in alkaline medium, and 4 nm CdTe QDs was used as catalysts to enhance the reaction sensitivity. The CL intensity of CdTe QDs-luminol-KMnO4 was strongly inhibited in the presence of 2-methoxyestradiol (2-ME) and the relative CL intensity was in linear correlation with the concentration of 2-ME. Based on this inhibition, a novel CL method with a lower detection limit and wider linear range was developed for the determination of 2-ME. The detection limit of plasma samples was 3.07×10(-10) g mL(-1) with a relative standard deviation of 0.24% for 8.0×10(-9) g mL(-1) 2-ME. The method was successfully applied for determination of 2-ME in plasma samples. The possible CL reaction mechanism was also discussed briefly. Copyright © 2014. Published by Elsevier B.V.

  19. Application of silver nanoparticles to the chemiluminescence determination of cefditoren pivoxil using the luminol-ferricyanide system.

    PubMed

    Alarfaj, Nawal A; Aly, Fatma A; El-Tohamy, Maha F

    2015-02-01

    A new simple, accurate and sensitive sequential injection analysis chemiluminescence (CL) detection method for the determination of cefditoren pivoxil (CTP) has been developed. The developed method was based on the enhancement effect of silver nanoparticles on the CL signal arising from a luminol-potassium ferricyanide reaction in the presence of CTP. The optimum conditions relevant to the effect of luminol, potassium ferricyanide and silver nanoparticle concentrations were investigated. The proposed method showed linear relationships between relative CL intensity and the investigated drug concentration at the range 0.001-5000 ng/mL, (r = 0.9998, n = 12) with a detection limit of 0.5 pg/mL and quantification limit of 0.001 ng/mL. The relative standard deviation was 1.6%. The proposed method was employed for the determination of CTP in bulk drug, in its pharmaceutical dosage forms and biological fluids such as human serum and urine. The interference of some common additive compounds such as glucose, lactose, starch, talc and magnesium stearate was investigated. In addition, the interference of some related cephalosporins was tested. No interference was recorded. The obtained sequential injection analysis-CL results were statistically compared with those from a reported method and did not show any significant differences. Copyright © 2014 John Wiley & Sons, Ltd.

  20. Determination of ampicillin sodium using the cupric oxide nanoparticles-luminol-H2 O2 chemiluminescence reaction.

    PubMed

    Iranifam, Mortaza; Kharameh, Merhnaz Khabbaz

    2014-09-01

    A simple and sensitive chemiluminescence (CL) method has been developed for the determination of ampicillin sodium at submicromolar levels. The method is based on the inhibitory effect of ampicillin sodium on the cupric oxide nanoparticles (CuO NPs)-luminol-H2 O2 CL reaction. Experimental parameters affecting CL inhibition including concentrations of CuO NPs, luminol, H2 O2 and NaOH were optimized. Under optimum conditions, the calibration plot was linear in the analyte concentration range 4.0 × 10(-7) -4.0 × 10(-6) mol/L. The limit of detection was 2.6 × 10(-7) mol/L and the relative standard deviation (RSD) for six replicate determinations of 1 × 10(-6) mol/L ampicillin sodium was 4.71%. Also, X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis were employed to characterize the CuO NPs. The utility of the proposed method was demonstrated by determining ampicillin sodium in pharmaceutical preparation. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Highly sensitive luminol electrochemiluminescence immunosensor based on ZnO nanoparticles and glucose oxidase decorated graphene for cancer biomarker detection.

    PubMed

    Cheng, Yinfeng; Yuan, Ruo; Chai, Yaqin; Niu, Huan; Cao, Yaling; Liu, Huijing; Bai, Lijuan; Yuan, Yali

    2012-10-01

    In this work, we reported a sandwiched luminol electrochemiluminescence (ECL) immunosensor using ZnO nanoparticles (ZnONPs) and glucose oxidase (GOD) decorated graphene as labels and in situ generated hydrogen peroxide as coreactant. In order to construct the base of the immunosensor, a hybrid architecture of Au nanoparticles and graphene by reduction of HAuCl(4) and graphene oxide (GO) with ascorbic acid was prepared. The resulted hybrid architecture modified electrode provided an excellent platform for immobilization of antibody with good bioactivity and stability. Then, ZnONPs and GOD functionalized graphene labeled secondary antibody was designed for fabricating a novel sandwiched ECL immunosensor. Enhanced sensitivity was obtained by in situ generating hydrogen peroxide with glucose oxidase and the catalysis of ZnONPs to the ECL reaction of luminol-H(2)O(2) system. The as-prepared ECL immunosensor exhibited excellent analytical property for the detection of carcinoembryonic antigen (CEA) in the range from 10 pg mL(-1) to 80 ng mL(-1) and with a detection limit of 3.3 pg mL(-1) (SN(-1)=3). The amplification strategy performed good promise for clinical application of screening of cancer biomarkers.

  2. Functionalization of indium tin oxide electrode with both of dendrimer-encapsulated Pt nanoparticles and chemically converted graphenes for enhanced electrochemiluminescence of luminol/H2O2.

    PubMed

    Yoon, Jisoo; Cho, Taehoon; Lim, Hyojung; Kim, Joohoon

    2016-10-01

    Here, we report highly enhanced electrochemiluminescence (ECL) of luminol in the presence of H2O2 on indium tin oxides (ITOs) modified with both of dendrimer-encapsulated Pt nanoparticles (Pt DENs) and chemically converted graphenes (CCGs). The ITO electrodes were electrochemically modified with size-monodisperse Pt DENs via electrooxidative grafting of the terminal amines of the dendrimers encapsulating Pt nanoparticles. The Pt DEN-modified ITOs were then decorated with CCG sheets via electrostatic attachments of graphene oxides (GOs) and subsequent chemical reduction of the GOs to the CCGs. The resulting CCG-Pt DEN/ITO electrodes exhibited highly catalyzed electrochemical oxidation of luminol/H2O2, leading to significantly enhanced ECL of the luminol/H2O2 system, i.e., ∼15-fold enhancement, compared to ECL emission from bare ITOs even at lower applied potentials, which allowed sensitive ECL-based analysis of H2O2 using the CCG-Pt DEN/ITOs. Graphical abstract We report the highly enhanced electrochemiluminescence of the luminol/H2O2 system on the indium tin oxide electrodes modified with both of Pt nanoparticles and chemically converted graphenes using amine-terminated dendrimers.

  3. Alterations in luminol-enhanced chemiluminescence from nondiluted whole blood in the course of low-level laser therapy of angina pectoris patients

    NASA Astrophysics Data System (ADS)

    Voeikov, Vladimir L.; Novikov, Cyril N.; Siuch, Natalia I.

    1997-05-01

    Addition of Luminol to nondiluted blood of healthy donors results in a short and weak increase of chemiluminescence (CL) from it. Contrary to that in 25 cases of stable angina pectoris the intensity of CL from blood of patients sharply increased upon addition of luminol exceeding that form healthy donors' blood 10-100-fold. 24 hours after the 3D intravenous low-level treatment CL burst in patients' blood in the presence of Luminol was in general significantly lower than before the beginning of the treatment. After the 7th treatment the pattern of CL kinetics was in most cases similar to that of healthy donors' blood. However, after the 10th treatment intensity of Luminol-enhanced CL usually increased and for blood of some patients even exceeded its values obtained before the treatment. Some correlation CL from nondiluted blood with neutrophil activity studied by NTB-test and plasma viscosity of same blood was noted. Using highly sensitive single photon counters it is possible to reveal abnormal levels of CL from no more than 0.1-0.2 ml of blood within 3-5 min.

  4. Luminol-dependent chemiluminescence is related to the extracellularly released reactive oxygen intermediates in the case of rat neutrophils activated by formyl-methionyl-leucyl-phenylalanine.

    PubMed

    Németh, Krisztina; Fûrész, József; Csikor, Katalin; Schweitzer, Katalin; Lakatos, Susan

    2002-01-01

    Luminol is a non-radical-specific amplifying molecule which produces light upon interaction with various reactive oxygen intermediates (ROIs). ROI production of rat peritoneal polymorphonuclear leukocytes (PMNLs) elicited by 2.3 microM formyl-methionyl-leucyl-phenylalanine (fMLP) results in a biphasic luminol-dependent chemiluminescence (LDCL) signal. Whereas ROIs are also produced intracellularly, as judged by flow cytometry, addition of non-membrane-permeable catalase reduces the first and second phases of the LDCL signal to around 3% and less than 3%, respectively. This suggests that in the case of fMLP-stimulated rat PMNLs, the LDCL signal is related to the ROIs in the extracellular medium and hydrogen peroxide has a key role in the formation of the LDCL signal. In the presence of the non-specific myeloperoxidase inhibitor Na-azide, the first phase of the LDCL signal decreases slightly (87+/-8%), while the second phase almost disappears (< 3%), indicating the myeloperoxidase dependence of the second phase. The hydroxyl radical scavenger histidine results in an 84+/-4% and a 71+/-4% decrease in the intensity of the first and second phases, respectively. Based on these data, it is concluded that hydrogen peroxide might be the source of hydroxyl radicals directly oxidizing luminol in the first phase of the LDCL signal, while in the second phase it serves as a substrate of myeloperoxidase in the peroxidation reaction of the luminol.

  5. An ultrasensitive luminol cathodic electrochemiluminescence immunosensor based on glucose oxidase and nanocomposites: graphene-carbon nanotubes and gold-platinum alloy.

    PubMed

    Jiang, Xinya; Chai, Yaqin; Yuan, Ruo; Cao, Yaling; Chen, Yingfeng; Wang, Haijun; Gan, Xianxue

    2013-06-14

    In the present study, a novel and ultrasensitive electrochemiluminescence (ECL) immunosensor based on luminol cathodic ECL was fabricated by using Au nanoparticles and Pt nanoparticles (nano-AuPt) electrodeposited on graphene-carbon nanotubes nanocomposite as platform for the detection of carcinoembryonic antigen (CEA). For this introduced immunosensor, graphene (GR) and single wall carbon nanotubes (CNTs) dispersed in chitosan (Chi-GR-CNTs) were firstly decorated on the bare gold electrode (GE) surface. Then nano-AuPt were electrodeposited (DpAu-Pt) on the Chi-GR-CNTs modified electrode. Subsequently, glucose oxidase (GOD) was employed to block the non-specific sites of electrode surface. When glucose was present in the working buffer solution, GOD immediately catalyzed the oxidation of glucose to in situ generate hydrogen peroxide (H2O2), which could subsequently promote the oxidation of luminol with an amplified cathodic ECL signal. The proposed immunosensor was performed at low potential (-0.1 to 0.4V) and low concentration of luminol. The CEA was determined in the range of 0.1 pg mL(-1) to 40 ng mL(-1) with a limit of detection down to 0.03 pg mL(-1) (SN(-1)=3). Moreover, with excellent sensitivity, selectivity, stability and simplicity, the as-proposed luminol-based ECL immunosensor provided great potential in clinical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Determination of cysteine and glutathione based on the inhibition of the dinuclear Cu(II)-catalyzed luminol-H2O2 chemiluminescence reaction

    NASA Astrophysics Data System (ADS)

    Chaichi, Mohammad Javad; Ehsani, Mahjoobeh; Khajvand, Tahereh; Golchoubian, Hamid; Rezaee, Ehsan

    2014-03-01

    The catalyzed luminol chemiluminescent reaction has received a great amount of attention because of its high sensitivity and low background signal which make the reaction an attractive analytical chemistry tool. The present study, introduces the beneficial catalytic effects of dinuclear Cu(II) complex [Cu2L2(TAE)]X2, where TAE = tetraacetylethane; L = N,N'-dibenzylethylenediamine and X = ClO4 on the luminol chemiluminescent reaction as a novel probe for the determination of glutathione (GSH) and L-cysteine (CySH) in human serum and urine. The [Cu2L2(TAE)]X2 has exhibited highly efficient catalytic activity of luminol CL as an artificial peroxidase model at pH as low as 7.5 in water in the presence of H2O2ṡGSH and CySH can induce a sharp decrease in CL intensity from the [Cu2L2(TAE)]X2-catalyzed luminol system. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentrations of GSH and CySH in the range of 1.0 × 10-7-1.0 × 10-4 M, with detection limits (S/N = 3) of 2.7 × 10-8 and 6.8 × 10-8 M and RSD < 4.2% (n = 7) for GSH and CySH, respectively.

  7. Fast and sensitive chemiluminescence assay of aminophylline in human serum using luminol-diperiodatoargentate(III) system catalyzed by coated iron nanoparticles

    NASA Astrophysics Data System (ADS)

    Rezaei, B.; Ensafi, Ali A.; Zarei, L.

    2012-05-01

    The CL intensity of luminol-diperiodatoargentate(III) (DPA) system is strongly enhanced by addition of iron nanoparticles (FeNPs) covered with C12E4. On injection of aminophylline into luminol-DPA-FeNPs system, the CL intensity is significantly increased. On this basis, a sensitive CL assay was developed for determination of AmP in human serum. FeNPs could catalyze the oxidation rate of luminol in the present of oxygen. Also, the CL intensity of luminol-DPA-FeNPs system is significantly increased in the presence of aminophylline (AmP). Based on this ruling, a sensitive CL assay was developed for determination of AmP in human serum. The influences of analytical variables on the CL signal were studied and optimized. Under the optimum conditions in the present of FeNPs, the CL intensity is linearly increased with AmP concentration in the range of 1.0 × 10-8-2.0 × 10-6 mol L-1. The detection limit was 9.8 × 10-9 mol L-1 AmP and the relative standard deviation for ten parallel measurements of 8.0 × 10-7 mol L-1 AmP was also 4.8%. The proposed system was successfully applied to determine AmP in human serum samples.

  8. Fast and sensitive chemiluminescence assay of aminophylline in human serum using luminol-diperiodatoargentate(III) system catalyzed by coated iron nanoparticles.

    PubMed

    Rezaei, B; Ensafi, Ali A; Zarei, L

    2012-05-01

    The CL intensity of luminol-diperiodatoargentate(III) (DPA) system is strongly enhanced by addition of iron nanoparticles (FeNPs) covered with C12E4. On injection of aminophylline into luminol-DPA-FeNPs system, the CL intensity is significantly increased. On this basis, a sensitive CL assay was developed for determination of AmP in human serum. FeNPs could catalyze the oxidation rate of luminol in the present of oxygen. Also, the CL intensity of luminol-DPA-FeNPs system is significantly increased in the presence of aminophylline (AmP). Based on this ruling, a sensitive CL assay was developed for determination of AmP in human serum. The influences of analytical variables on the CL signal were studied and optimized. Under the optimum conditions in the present of FeNPs, the CL intensity is linearly increased with AmP concentration in the range of 1.0×10(-8)-2.0×10(-6) mol L(-1). The detection limit was 9.8×10(-9) mol L(-1) AmP and the relative standard deviation for ten parallel measurements of 8.0×10(-7)mol L(-1) AmP was also 4.8%. The proposed system was successfully applied to determine AmP in human serum samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Nanoparticles based on quantum dots and a luminol derivative: implications for in vivo imaging of hydrogen peroxide by chemiluminescence resonance energy transfer.

    PubMed

    Lee, Eun Sook; Deepagan, V G; You, Dong Gil; Jeon, Jueun; Yi, Gi-Ra; Lee, Jung Young; Lee, Doo Sung; Suh, Yung Doug; Park, Jae Hyung

    2016-03-18

    Overproduction of hydrogen peroxide is involved in the pathogenesis of inflammatory diseases such as cancer and arthritis. To image hydrogen peroxide via chemiluminescence resonance energy transfer in the near-infrared wavelength range, we prepared quantum dots functionalized with a luminol derivative.

  10. Electrochemiluminescence immunosensor based on multifunctional luminol-capped AuNPs@Fe3O4 nanocomposite for the detection of mucin-1.

    PubMed

    Wang, Jing-Xi; Zhuo, Ying; Zhou, Ying; Yuan, Ruo; Chai, Ya-Qin

    2015-09-15

    In this work, a novel and multifunctional nanocomposite of luminol capped gold modified Fe3O4 (Lu-AuNPs@Fe3O4) was utilized as the carrier of secondary antibody (Ab2) to fabricate a sandwiched electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of mucin-1 (MUC1). Herein, the luminol capped gold nanoparticles (Lu-AuNPs) were synthesized with HAuCl4 and luminol by the help of NaBH4 at room temperature, and then Lu-AuNPs were adsorbed on the Fe3O4 magnetic nanoparticles (MNPs) to form the nanocomposite of Lu-AuNPs@Fe3O4 via electrostatic interaction. Fe3O4 MNPs in Lu-AuNPs@Fe3O4 exhibited excellent conductivity and admirable catalytic activity in H2O2 decomposition, which could enhance the ECL efficiency of luminol-H2O2 system. In addition, the substrates of gold coated ZnO nanoparticles (AuNPs@ZnO), providing large specific surface areas for primary antibody (Ab1) capturing, were modified on the electrode. As a result, a wide linear range of 7 orders of magnitude from 10 fg/mL to 10 ng/mL was obtained with an ultralow detection limit of 4.5 fg/mL for MUC1. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Determination of cysteine and glutathione based on the inhibition of the dinuclear Cu(II)-catalyzed luminol-H2O2 chemiluminescence reaction.

    PubMed

    Chaichi, Mohammad Javad; Ehsani, Mahjoobeh; Khajvand, Tahereh; Golchoubian, Hamid; Rezaee, Ehsan

    2014-03-25

    The catalyzed luminol chemiluminescent reaction has received a great amount of attention because of its high sensitivity and low background signal which make the reaction an attractive analytical chemistry tool. The present study, introduces the beneficial catalytic effects of dinuclear Cu(II) complex [Cu2L2(TAE)]X2, where TAE=tetraacetylethane; L=N,N(')-dibenzylethylenediamine and X=ClO4 on the luminol chemiluminescent reaction as a novel probe for the determination of glutathione (GSH) and L-cysteine (CySH) in human serum and urine. The [Cu2L2(TAE)]X2 has exhibited highly efficient catalytic activity of luminol CL as an artificial peroxidase model at pH as low as 7.5 in water in the presence of H2O2⋅GSH and CySH can induce a sharp decrease in CL intensity from the [Cu2L2(TAE)]X2-catalyzed luminol system. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentrations of GSH and CySH in the range of 1.0×10(-7)-1.0×10(-4) M, with detection limits (S/N=3) of 2.7×10(-8) and 6.8×10(-8) M and RSD<4.2% (n=7) for GSH and CySH, respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. A dual-potential electrochemiluminescence ratiometric approach based on graphene quantum dots and luminol for highly sensitive detection of protein kinase activity.

    PubMed

    Zhao, Hui-Fang; Liang, Ru-Ping; Wang, Jing-Wu; Qiu, Jian-Ding

    2015-08-14

    A novel Au NP mediated dual-potential ECL ratiometric approach for highly sensitive protein kinase activity and inhibition assay has been developed based on the simultaneous decrease of cathodic ECL from GQDs and enhancement of anodic ECL from luminol in the same bioanalysis.

  13. Escherichia coli ATCC 8739 Adapts to the Presence of Sodium Chloride, Monosodium Glutamate, and Benzoic Acid after Extended Culture

    PubMed Central

    Lee, Chin How; Oon, Jack S. H.; Lee, Kun Cheng; Ling, Maurice H. T.

    2012-01-01

    Escherichia coli is commonly found in intestine of human, and any changes in their adaptation or evolution may affect the human body. The relationship between E. coli and food additives is less studied as compared to antibiotics. E. coli within our human gut are consistently interacting with the food additives; thus, it is important to investigate this relationship. In this paper, we observed the evolution of E. coli cultured in different concentration of food additives (sodium chloride, benzoic acid, and monosodium glutamate), singly or in combination, over 70 passages. Adaptability over time was estimated by generation time and cell density at stationary phase. Polymerase chain reaction (PCR)/restriction fragments length polymorphism (RFLP) using 3 primers and restriction endonucleases, each was used to characterize adaptation/evolution at genomic level. The amplification and digestion profiles were tabulated and analyzed by Nei-Li dissimilarity index. Our results demonstrate that E. coli in every treatment had adapted over 465 generations. The types of stress were discovered to be different even though different concentrations of same additives were used. However, RFLP shows a convergence of genetic distances, suggesting the presence of global stress response. In addition, monosodium glutamate may be a nutrient source and support acid resistance in E. coli. PMID:23724334

  14. A novel sandwich electrochemiluminescence immunosensor for ultrasensitive detection of carbohydrate antigen 19-9 based on immobilizing luminol on Ag@BSA core/shell microspheres.

    PubMed

    Zhang, Amin; Xiang, Hongkun; Zhang, Xin; Guo, Weiwei; Yuan, Enhui; Huang, Chusen; Jia, Nengqin

    2016-01-15

    A novel sandwich-type electrochemiluminescence immunosensor based on immobilizing luminol on Ag@BSA core/shell microspheres (Ag@BSA-luminol) for ultrasensitive detection of tumor marker carbohydrate antigen 19-9 (CA19-9) has been developed. Herein, magnetic carbon nanotubes (MAGCNTs) decorated with polyethylenimine (PEI) was used to construct the base of the immunosensor. MAGCNTs with prominent electrical conductivity and high surface area could be beneficial for promoting the electron transfer and loading plenty of primary antibodies (Ab1) via glutaraldehyde (GA). Meanwhile, the magnetic property of MAGCNTs makes it easy to be attached to the surface of magnetic glass carbon electrode (MGCE) through magnetism interaction, which provides an outstanding platform for this immunosensor. Moreover, Ag@BSA microspheres with large surface area, good stability, and excellent biocompatibility were desirable candidates for effective cross-link of CA19-9 detection antibodies (Ab2). A more interesting thing was that ELISA color reaction was used as an ultrasensitive strategy for identifying Ab2 was successfully coated on Ag@BSA with the naked eye. Additionally, we immobilized the luminol on the surface of Ag@BSA to prepare the target immunosensor. Immobilization of luminol on the surface of Ag@BSA could decrease the distance between luminophores and the electrode surface, leading to great enhancement of the ECL intensity of luminol in the present of hydrogen peroxide (H2O2). Under the optimal conditions, the intensity of the ECL immunosensor increased linearly with the logarithm of CA19-9 concentration in a wide linear range from 0.0005 to 150UmL(-1) with a detection limit of 0.0002UmL(-1) (S/N=3). All the results suggested the prepared CA19-9 immunosensor displayed high sensitivity, excellent stability and good specificity. The developed method opened a new avenue to clinical bioassay. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Evaluation of lophine derivatives as L-012 (luminol analog)-dependent chemiluminescence enhancers for measuring horseradish peroxidase and H2O2.

    PubMed

    Ichibangase, T; Ohba, Y; Kishikawa, N; Nakashima, K; Kuroda, N

    2014-03-01

    8-Amino-5-chloro-7-phenylpyrido[3,4-d]pyridazine-1,4(2H,3H)dione (L-012) was recently synthesized as a new chemiluminescence (CL) probe; the light intensity and the sensitivity of L-012 are higher than those of other CL probes such as luminol. Previously, our group developed four lophine-based CL enhancers of the horseradish peroxidase (HRP)-catalyzed CL oxidation of luminol, namely 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (HDI), 2-(4-hydroxyphenyl)-4,5-di(2-pyridyl)imidazole (HPI), 4-(4,5-diphenyl-1H-imidazol-2-yl)phenylboronic acid (DPA), and 4-[4,5-di(2-pyridyl)-1H-imidazol-2-yl]phenylboronic acid (DPPA), and showed that DPPA was suitable for the photographic detection of HRP. In this study, we replaced luminol with L-012 and evaluated these as L-012-dependent CL enhancers. In addition, to detect HRP and/or H2O2 with higher sensitivity, each detection condition for the L-012-HRP-H2O2 enhanced CL was optimized. All the derivatives enhanced the L-012-dependent CL as well as luminol CL; HPI generated the highest enhanced luminescence. Under optimized conditions for HRP detection, the detection limit of HRP was 0.08 fmol. By contrast, the detection limit of HRP with the enhanced L-012-dependent CL using 4-iodophenol, which is a common enhancer of luminol CL, was 1.1 fmol. With regard to H2O2 detection, the detection limits for enhanced CL with HPI and 4-iodophenol were 0.29 and 1.5 pmol, respectively. Therefore, it is demonstrated that HPI is the most superior L-012-dependent CL enhancer. Copyright © 2013 John Wiley & Sons, Ltd.

  16. PILOT SCALE TESTING OF MONOSODIUM TITANATE MIXING FOR THE SRS SMALL COLUMN ION EXCHANGE PROCESS - 11224

    SciTech Connect

    Poirier, M.; Restivo, M.; Williams, M.; Herman, D.; Steeper, T.

    2011-01-25

    The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and select actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is to determine the requirements for the pumps to suspend the MST particles so that they can contact the strontium and actinides in the liquid and be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of SRS Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations). The conclusions from this work follow: (i) Neither two standard slurry pumps nor two quad volute slurry pumps will provide sufficient power to initially suspend MST in an SRS waste tank. (ii) Two Submersible Mixer Pumps (SMPs) will provide sufficient power to initially suspend MST in an SRS waste tank. However, the testing shows the required pump discharge velocity is close to the maximum discharge velocity of the pump (within 12%). (iii) Three SMPs will provide sufficient power to initially suspend MST in an SRS waste tank. The testing shows the required pump discharge velocity is 66% of the maximum discharge velocity of the pump. (iv) Three SMPs are needed to resuspend MST that has settled in a waste tank at nominal 45 C for four weeks. The testing shows the required pump discharge velocity is 77% of the maximum discharge velocity of the pump. Two SMPs are not sufficient to resuspend MST that settled under these

  17. Intra-articular basic calcium phosphate and monosodium urate crystals inhibit anti-osteoclastogenic cytokine signalling.

    PubMed

    Cunningham, C C; Corr, E M; McCarthy, G M; Dunne, A

    2016-12-01

    Basic calcium phosphate (BCP) and monosodium urate (MSU) crystals are particulates with potent pro-inflammatory effects, associated with osteoarthritis (OA) and gout, respectively. Bone erosion, due to increased osteoclastogenesis, is a hallmark of both arthropathies and results in severe joint destruction. The aim of this study was to investigate the effect of these endogenous particulates on anti-osteoclastogenic cytokine signalling. Human osteoclast precursors (OcP) were treated with BCP and MSU crystals prior to stimulation with Interleukin (IL-6) or Interferon (IFN-γ) and the effect on Signal Transducer and Activator of Transcription (STAT)-3 and STAT-1 activation in addition to Mitogen Activated Protein Kinase (MAPK) activation was examined by immunoblotting. Crystal-induced suppressor of cytokine signalling (SOCS) protein and SH-2 containing tyrosine phosphatase (SHP) expression was assessed by real-time polymerase chain reaction (PCR) in the presence and absence of MAPK inhibitors. Pre-treatment with BCP or MSU crystals for 1 h inhibited IL-6-induced STAT-3 activation in human OcP, while pre-treatment for 3 h inhibited IFN-γ-induced STAT-1 activation. Both crystals activated p38 and extracellular signal-regulated (ERK) MAPKs with BCP crystals also activating c-Jun N-terminal kinase (JNK). Inhibition of p38 counteracted the inhibitory effect of BCP and MSU crystals and restored STAT-3 phosphorylation. In contrast, STAT-1 phosphorylation was not restored by MAPK inhibition. Finally, both crystals potently induced the expression of SOCS-3 in a MAPK dependent manner, while BCP crystals also induced expression of SHP-1 and SHP-2. This study provides further insight into the pathogenic effects of endogenous particulates in joint arthropathies and demonstrates how they may contribute to bone erosion via the inhibition of anti-osteoclastogenic cytokine signalling. Potential targets to overcome these effects include p38 MAPK, SOCS-3 and SHP phosphatases

  18. Ultrasonography shows disappearance of monosodium urate crystal deposition on hyaline cartilage after sustained normouricemia is achieved.

    PubMed

    Thiele, Ralf G; Schlesinger, Naomi

    2010-02-01

    This study aimed at determining whether lowering serum urate (SU) to less than 6 mg/dl in patients with gout affects ultrasonographic findings. Seven joints in five patients with monosodium urate (MSU) crystal proven gout and hyperuricemia were examined over time with serial ultrasonography. Four of the five patients were treated with urate lowering drugs (ULDs) (allopurinol, n = 3; probenecid, n = 1). One patient was treated with colchicine alone. Attention was given to changes in a hyperechoic, irregular coating of the hyaline cartilage in the examined joints (double contour sign or "urate icing"). This coating was considered to represent precipitate of MSU crystals. Index joints included metacarpophalangeal (MCP) joints (n = 2), knee joints (n = 3), and first metatarsophalangeal (MTP) joints (n = 2). The interval between baseline and follow-up images ranged from 7 to 18 months. Serial SU levels were obtained during the follow-up period. During the follow-up period, three patients treated with ULD (allopurinol, n = 2; probenecid, n = 1) achieved a SU level of <6 mg/dl. In two patients, SU levels remained above 6 mg/dl (treated with allopurinol, n = 1; treated with colchicine, n = 1). At baseline, the double contour sign was seen in all patients. In those patients who achieved SU levels of <6 ml/dl, this sign had disappeared at follow-up. Disappearance of the double contour sign was seen in two knee joints, two first MTP joints, and one MCP joint. In contrast, disappearance of the double contour sign was not seen in patients who maintained a SU level > or =7 mg/dl. In one patient treated with allopurinol, SU levels improved from 13 to 7 mg/dl during the follow-up period. Decrease, but not resolution of the hyperechoic coating was seen in this patient. In the patient treated with colchicine alone, SU levels remained >8 mg/dl, and no sonographic change was observed. In our patients, sonographic signs of deposition of MSU crystals on the surface of hyaline cartilage

  19. Resveratrol, a natural antioxidant, protects monosodium iodoacetate-induced osteoarthritic pain in rats.

    PubMed

    Wang, Zhu-Min; Chen, Yong-Cai; Wang, Da-Peng

    2016-10-01

    Osteoarthritis (OA) is a chronic progressive joint disease characterized by advanced joint pain, subchondral bone sclerosis and articular cartilage degeneration. Resveratrol has been shown to have anti-inflammatory, cardioprotective and antioxidant properties and to inhibit platelet aggregation and coagulation. However, the effects of resveratrol on OA have not been examined. In this study, we investigate the protective effects of resveratrol on monosodium iodoacetate (MIA)-induced OA through inhibition of cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) signaling pathway in a rat model. A single intra-articular injection of MIA was injected into rats for the induction of OA. The mechanical, heat and cold hyperalgesia were measured at days 0, 7 and 14. The serum and synovial fluid levels of IL-1β, IL-10 and TNF-α and osteocalcin were measured by enzyme-linked immunosorbent assay. The mRNA and protein expressions of IL-1β, IL-10, TNF-α, Il-6, MMP-13 and COX-2 and iNOS were determined by RT-PCR and western blot, respectively. Osteoarthritic lesion in the knee joint was evaluated by histological analysis. MIA-injected rats treated with resveratrol at a dose of either 5 or 10mg/kg body weight were significantly reduced hyperalgesia of mechanical, heat and cold and increased the vertical and horizontal movements. Subsequently, MIA-injected rats increased serum and synovial fluid levels of IL-1β, IL-10, IL-6, TNF-α, MMP-13 and osteoclastic activity marker, osteocalcin and its articular cartilage mRNA and protein expressions. Further, MIA-injected rats increased COX-2 and iNOS mRNA and protein expressions were decreased by resveratrol. The protective effect of resveratrol was comparable to a reference drug, etoricoxib. The cartilage damage induced by MIA were attenuated by resveratrol. Taken together, resveratrol has the potential to improve MIA-induced cartilage damage by inhibiting the levels and expressions of inflammatory mediators suggesting

  20. Macrophage-derived IL-1β enhances monosodium urate crystal-triggered NET formation.

    PubMed

    Sil, Payel; Wicklum, Haley; Surell, Chandler; Rada, Balázs

    2017-03-01

    Arthritic gout is caused by joint inflammation triggered by the damaging effects of monosodium uric acid (MSU) crystal accumulation in the synovial space. Neutrophils play a major role in mediating joint inflammation in gout. Along with neutrophils, other immune cells, such as macrophages, are present in inflamed joints and contribute to gout pathogenesis. Neutrophils form neutrophil extracellular traps (NETs) in response to MSU crystals. In the presence of MSU crystals, macrophages release IL-1β, a cytokine crucial to initiate gout pathogenesis and neutrophil recruitment. Our research investigated interactions between human macrophages and neutrophils in an in vitro model system and asked how macrophages affect NET formation stimulated by MSU crystals. Human neutrophils and PBMCs were isolated from peripheral blood of healthy volunteers. PBMCs were differentiated into macrophages in vitro using human M-CSF. Human neutrophils were pretreated with macrophage-conditioned media, neutrophil-conditioned media, recombinant human IL-1β or anakinra prior to stimulation by MSU crystals. Interaction of neutrophils with MSU crystals was evaluated by live imaging using confocal microscopy. The presence of myeloperoxidase (MPO) and neutrophil elastase (NE) was measured by ELISA. NET formation was quantitated by Sytox Orange-based extracellular DNA release assay and NE-DNA ELISA. AggNET formation was assessed by macroscopic evaluation. We found that crystal- and cell-free supernatants of macrophages stimulated with MSU crystals promote MSU crystal-stimulated NET formation in human neutrophils. This observation was confirmed by additional assays measuring the release of MPO, NE, and the enzymatic activity of NE. MSU crystal-induced NET formation remained unchanged when neutrophil supernatants were tested. IL-1β is a crucial cytokine orchestrating the onset of inflammation in gout and is known to be released in large amounts from macrophages following MSU crystal stimulation

  1. Sex-dimorphism in Cardiac Nutrigenomics: effect of Trans fat and/or Monosodium Glutamate consumption

    PubMed Central

    2011-01-01

    Background A paucity of information on biological sex-specific differences in cardiac gene expression in response to diet has prompted this present nutrigenomics investigation. Sexual dimorphism exists in the physiological and transcriptional response to diet, particularly in response to high-fat feeding. Consumption of Trans-fatty acids (TFA) has been linked to substantially increased risk of heart disease, in which sexual dimorphism is apparent, with males suffering a higher disease rate. Impairment of the cardiovascular system has been noted in animals exposed to Monosodium Glutamate (MSG) during the neonatal period, and sexual dimorphism in the growth axis of MSG-treated animals has previously been noted. Processed foods may contain both TFA and MSG. Methods We examined physiological differences and changes in gene expression in response to TFA and/or MSG consumption compared to a control diet, in male and female C57BL/6J mice. Results Heart and % body weight increases were greater in TFA-fed mice, who also exhibited dyslipidemia (P < 0.05). Hearts from MSG-fed females weighed less than males (P < 0.05). 2-factor ANOVA indicated that the TFA diet induced over twice as many cardiac differentially expressed genes (DEGs) in males compared to females (P < 0.001); and 4 times as many male DEGs were downregulated including Gata4, Mef2d and Srebf2. Enrichment of functional Gene Ontology (GO) categories were related to transcription, phosphorylation and anatomic structure (P < 0.01). A number of genes were upregulated in males and downregulated in females, including pro-apoptotic histone deacetylase-2 (HDAC2). Sexual dimorphism was also observed in cardiac transcription from MSG-fed animals, with both sexes upregulating approximately 100 DEGs exhibiting sex-specific differences in GO categories. A comparison of cardiac gene expression between all diet combinations together identified a subset of 111 DEGs significant only in males, 64 DEGs significant in females only

  2. Sex-dimorphism in cardiac nutrigenomics: effect of trans fat and/or monosodium glutamate consumption.

    PubMed

    Collison, Kate S; Zaidi, Marya Z; Maqbool, Zakia; Saleh, Soad M; Inglis, Angela; Makhoul, Nadine J; Bakheet, Razan; Shoukri, Mohammed; Al-Mohanna, Futwan A

    2011-11-12

    A paucity of information on biological sex-specific differences in cardiac gene expression in response to diet has prompted this present nutrigenomics investigation. Sexual dimorphism exists in the physiological and transcriptional response to diet, particularly in response to high-fat feeding. Consumption of Trans-fatty acids (TFA) has been linked to substantially increased risk of heart disease, in which sexual dimorphism is apparent, with males suffering a higher disease rate. Impairment of the cardiovascular system has been noted in animals exposed to Monosodium Glutamate (MSG) during the neonatal period, and sexual dimorphism in the growth axis of MSG-treated animals has previously been noted. Processed foods may contain both TFA and MSG. We examined physiological differences and changes in gene expression in response to TFA and/or MSG consumption compared to a control diet, in male and female C57BL/6J mice. Heart and % body weight increases were greater in TFA-fed mice, who also exhibited dyslipidemia (P < 0.05). Hearts from MSG-fed females weighed less than males (P < 0.05). 2-factor ANOVA indicated that the TFA diet induced over twice as many cardiac differentially expressed genes (DEGs) in males compared to females (P < 0.001); and 4 times as many male DEGs were downregulated including Gata4, Mef2d and Srebf2. Enrichment of functional Gene Ontology (GO) categories were related to transcription, phosphorylation and anatomic structure (P < 0.01). A number of genes were upregulated in males and downregulated in females, including pro-apoptotic histone deacetylase-2 (HDAC2). Sexual dimorphism was also observed in cardiac transcription from MSG-fed animals, with both sexes upregulating approximately 100 DEGs exhibiting sex-specific differences in GO categories. A comparison of cardiac gene expression between all diet combinations together identified a subset of 111 DEGs significant only in males, 64 DEGs significant in females only, and 74 transcripts

  3. The Effects of Monosodium Glutamate and Tannic Acid on Adult Rats

    PubMed Central

    Ugur Calis, Ibrahim; Turgut Cosan, Didem; Saydam, Faruk; Kerem Kolac, Umut; Soyocak, Ahu; Kurt, Hulyam; Veysi Gunes, Hasan; Sahinturk, Varol; Sahin Mutlu, Fezan; Ozdemir Koroglu, Zeynep; Degirmenci, Irfan

    2016-01-01

    Background Monosodium glutamate (MSG) is a widely-used flavor enhancer and stabilizer in ready-made or packaged foods. The excessive use of MSG has been shown to increase oxidative stress in different organ systems and causes glucose metabolism disorders, obesity, and coronary diseases. Objectives In this study, the antioxidant activity of tannic acid was investigated experimentally with respect to its protective effects against overdosed MSG-induced oxidative stress in rats. The study took place in Turkey in August 2013. Methods Four groups (n = 7) of three- to four-month-old Sprague-Dawley female rats were used in this study. The first group was the control, who were administered saline. The second group received tannic acid (50 mg/kg, 3 days) intraperitoneally (i.p.). The third group received MSG (2 g/kg, 7 days) i.p., and the fourth group received both tannic acid (50 mg/kg, 3 days, pretreatment) and MSG (2 g/kg, 7 days) i.p. The animals were euthanized ten days later. Blood was collected for determining the hematological values and blood glucose levels. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were determined in the brain, liver, and kidney homogenates, and in the erythrocyte hemolysate. Histopathological examination of the brain, liver, and kidneys was conducted through hematoxylin-eosin staining. Results The data showed that the tannic acid treatment statistically decreased the MDA levels in the brain tissues of the group administered MSG and tannic acid (P < 0.001) when compared to the corresponding values of the control group. The SOD activities in the blood hemolysates of the MSG and tannic acid group increased when compared to the corresponding values for the MSG group (P < 0.01). Additionally, we found that pretreatment with tannic acid reduced blood glucose levels in comparison to the levels of the MSG group (P = 0.029). The results of our study show that tannic acid pretreatment in adult rats decreased blood glucose levels and

  4. Neural correlates of hyperalgesia in the monosodium iodoacetate model of osteoarthritis pain

    PubMed Central

    Abaei, Maryam; Sagar, Devi R; Stockley, Elizabeth G; Spicer, Clare H; Prior, Malcolm; Auer, Dorothee P

    2016-01-01

    Background The mechanisms driving osteoarthritic pain remain poorly understood, but there is increasing evidence for a role of the central nervous system in the chronification of pain. We used functional magnetic resonance imaging to investigate the influence of a model of unilateral knee osteoarthritis on nociceptive processing. Results Four to five weeks post intra-articular injection of monosodium iodoacetate (MIA, 1 mg) into the left knee, Sprague Dawley rats were anesthetized for functional magnetic resonance imaging studies to characterize the neural response to a noxious stimulus (intra-articular capsaicin injection). In a two-arm cross-over design, 5 µM/50 µl capsaicin was injected into either the left knee (n = 8, CAPS-MIA) or right control knee (n = 8, CAPS-CON), preceded by contralateral vehicle (SAL) injection. To assess neural correlates of mechanical hyperalgesia, hindpaws were stimulated with von Frey hairs (8 g: MIA; 15 g: control knee, based on behavioral withdrawal responses). The CAPS-MIA group exhibited significant activation of the periaqueductal gray, unilateral thalamus and bilateral mensencephalon, superior-colliculus, and hippocampus, with no significant activation in the other groups/conditions. Capsaicin injection increased functional connectivity in the mid-brain network and mediodorsal thalamic nucleus, hippocampus, and globus pallidus, which was significantly stronger in CAPS-MIA compared to CAPS-CON groups. Mechanical stimulation of the hyperalgesic (ipsilateral to MIA knee) and normalgesic (contralateral) hindpaws evoked qualitatively different brain activation with more widespread brainstem and anterior cingulate (ACC) activation when stimulating the hyperalgesic paw, and clearer frontal sensory activation from the normalgesic paw. Conclusions We provide evidence for modulation of nociceptive processing in a chronic knee osteoarthritis pain model with stronger brain activation and alteration of brain networks

  5. [Enhancement of luminol-dependent chemiluminescence in an aqueous NaCl/H2O2 solution by argon].

    PubMed

    Voeĭkov, V L; Khimich, M V

    2002-01-01

    It was found that the bubbling of argon through NaCl/H2O2 aqueous solutions results in the development of intense sustained luminol-dependent chemiluminescence. Bubbling of nitrogen and air through similar solutions does not result in such effect. The relationship between argon-supported chemiluminescence and initial concentrations of NaCl and H2O2 is characterized by threshold effects. In NaCl/H2O2 solutions blown with argon, hypochlorite was found, indicating that argon intensifies the reaction of chloride oxidation with H2O2. It is suggested that the enhancement of this reaction in aqueous solutions saturated with argon is related to specific changes in the properties of water, which is a highly nonequilibrium system. Possible consequences of relatively high concentrations of argon in the atmosphere for the chemical processes that occur in aqueous systems and, in particular, living systems are discussed.

  6. Phagocytosis by sheep alveolar macrophages: relationship between opsonin concentration and light emission in the presence of luminol.

    PubMed Central

    Ziprin, R L

    1978-01-01

    The observations reported may be applied to determining the effects of various compounds, e.g., environmental pollutants and agricultural chemicals, upon the phagocytic activity of alveolar macrophages, and the method described will aid in detecting compounds which alter Fc receptor activity. A direct linear relationship existed between the concentration of antibody used to opsonize bacterial particles and the quantity of luminol-dependent light emitted by a population of sheep alveolar macrophages exposed to the opsonized particles. The relationship can be illustrated with a Lineweaver-Burk-style double-reciprocal plot. An analogy is suggested between the kinetics of enzyme substrate reactions and the interaction of antibody-coated particles with Fc receptors on cell membranes. PMID:640735

  7. The chemiluminescence determination of 2-chloroethyl ethyl sulfide using luminol-AgNO3-silver nanoparticles system.

    PubMed

    Maddah, Bozorgmehr; Shamsi, Javad; Barsang, Mehran Jam; Rahimi-Nasrabadi, Mehdi

    2015-05-05

    A highly sensitive chemiluminescence (CL) method for the determination of 2-chloroethyl ethyl sulfide (2-CEES) was presented. It was found that 2-chloroethyl ethyl sulfide (2-CEES) could inhibit the CL of the luminol-AgNO3 system in the presence of silver nanoparticles in alkaline solution, which made it applicable for determination of 2-CEES. The presented method is simple, convenient, rapid and sensitive. Under the optimized conditions, the calibration curve was linear in the range of 0.0001-1ngmL(-1), with the correlation coefficient of 0.992; while the limit of detection (LOD), based on signal-to-noise ratio (S/N) of 3, was 6×10(-6)ngmL(-1). Also, the relative standard deviation (RSD, n=5) for determination of 2-CEES (0.50ngmL(-1)) was 3.1%. The method was successfully applied for the determination of 2-CEES in environmental aqueous samples.

  8. Rapid flow injection method for the determination of sulfite in wine using the permanganate-luminol luminescence system.

    PubMed

    Navarrro, Mercedes Villar; Payán, María Ramos; López, Miguel Angel Bello; Fernández-Torres, Rut; Mochón, Manuel Callejón

    2010-10-15

    A simple, rapid and sensitive chemiluminescence method for the determination of sulfite has been developed by combining flow-injection analysis and its sensitizing effect on the known chemiluminescence emission produced by the oxidation of luminol in alkaline medium; in this work permanganate has been proposed as oxidizing reactive. The optimum conditions for the chemiluminescence emission were established. The chemiluminescence was proportional to the sulfite concentration over the range 1.6 × 10(-5) and 4.0 × 10(-4)mol L(-1). The detection limit was 4.7 × 10(-6)mol L(-1) of sulfite. The method has been satisfactorily used for the determination of free and bound sulfite in wines.

  9. The ODN probes conjugating the Cu(II) complex enhance the luminol chemiluminescence by assembling on the DNA template.

    PubMed

    Taniguchi, Yosuke; Nitta, Akiko; Park, Sun Min; Kohara, Akiko; Uzu, Takahiro; Sasaki, Shigeki

    2010-12-15

    Potent peroxidase-like activity of the β-ketoenamine (1)-dicopper (II) complex (2) for the chemiluminescence (CL) of luminol either in the presence or absence of H(2)O(2) has been previously demonstrated by our group. In this study, the β-ketoenamine (1) as the ligand unit for copper(II) was incorporated into the oligonucleotide (ODN) probes. It has been shown that the catalytic activity of the ODN probes conjugating the ligand-Cu(II) complex is activated by hybridization with the target DNA with the complementary sequence. Thus, this study has successfully demonstrated the basic concept for the sensitive detection of nucleic acids by CL based on the template-inductive activation of the catalytic unit for CL.

  10. Flow-injection chemiluminescence determination of lisinopril using luminol-KMnO4 reaction catalyzed by silver nanoparticles.

    PubMed

    Li, Yinhuan; Li, Yankun; Yang, Yun

    2011-04-01

    A simple, sensitive, and rapid chemiluminescence method combined with flow-injection analysis was developed for the determination of lisinopril. It was found that the chemiluminescence (CL) signal arising from the reaction of alkaline luminol with KMnO(4) could be significantly increased by addition of lisinopril in the presence of silver nanoparticles. The experimental parameters affecting the chemiluminescence reaction were carefully studied and the chemiluminescence reaction mechanism was briefly discussed. Under the selected conditions, the chemiluminescence intensity was proportional to the concentration of lisinopril ranging from 0.1 mg/L to 20.0 mg/L. The detection limit was 0.027 mg/L lisinopril and the relative standard deviation for 4.0 mg/L lisinopril solution was 1.9% over eleven repeated measurements. The proposed method was applied to the determination of lisinopril in tablets and spiked human urine samples. © 2011 Society for Applied Spectroscopy

  11. Flow-injection chemiluminescence determination of catecholamines based on their enhancing effects on the luminol-potassium periodate system.

    PubMed

    Yao, Hong; Sun, Yuan Yuan; Lin, Xinhua; Cheng, Jinghua; Huang, Liying

    2006-01-01

    A rapid and sensitive chemiluminescence (CL) method using flow injection analysis is described for the determination of four catecholamines, dopamine, adrenaline, isoprenaline and noradrenaline, based on their greatly enhancing effects on the CL reaction of luminol-potassium periodate in basic solutions. The optimized chemical conditions for the chemiluminescence reaction were 1.0 x 10(-4) mol/L luminol and 1.0 x 10(-5) mol/L potassium periodate in 0.2 mol/L sodium hydroxide (NaOH). Under the optimized conditions, the calibration graphs relating the CL signal intensity (peak height) to the concentration of the analytes were curvilinear and they were suitable for determining dopamine, adrenaline, isoprenaline, and noradrenaline in the range 0.1-10 ng/mL, 0.1-100 ng/mL, 1-100 ng/mL and 5-50 ng/mL, respectively, with the relative standard deviations of 0.8-1.7%. The detection limits of the method are 0.02 ng/mL for dopamine, 0.01 ng/mL for adrenaline, 0.1 ng/mL for isoprenaline and 2.0 ng/mL for noradrenaline. The sampling frequency was calculated to be about 60/h. The selectivity of the method was good, because a series of common ions or excipients, such as K(+), Ba(2+), CO(3)(2-), NO(3)(-), SO(4)(2-), PO(4)(3-), sodium citrate, sodium bisulphite, oxidate dopamine, starch, lactose, carbamide and gelatin, could not produce interference when their concentrations were 1000-fold than those of dopamine. The present method was successfully applied to the determination of the four catecholamines in pharmaceutical injections.

  12. Simultaneous Determination of Size and Quantification of Gold Nanoparticles by Direct Coupling Thin layer Chromatography with Catalyzed Luminol Chemiluminescence

    PubMed Central

    Yan, Neng; Zhu, Zhenli; He, Dong; Jin, Lanlan; Zheng, Hongtao; Hu, Shenghong

    2016-01-01

    The increasing use of metal-based nanoparticle products has raised concerns in particular for the aquatic environment and thus the quantification of such nanomaterials released from products should be determined to assess their environmental risks. In this study, a simple, rapid and sensitive method for the determination of size and mass concentration of gold nanoparticles (AuNPs) in aqueous suspension was established by direct coupling of thin layer chromatography (TLC) with catalyzed luminol-H2O2 chemiluminescence (CL) detection. For this purpose, a moving stage was constructed to scan the chemiluminescence signal from TLC separated AuNPs. The proposed TLC-CL method allows the quantification of differently sized AuNPs (13 nm, 41 nm and 100 nm) contained in a mixture. Various experimental parameters affecting the characterization of AuNPs, such as the concentration of H2O2, the concentration and pH of the luminol solution, and the size of the spectrometer aperture were investigated. Under optimal conditions, the detection limits for AuNP size fractions of 13 nm, 41 nm and 100 nm were 38.4 μg L−1, 35.9 μg L−1 and 39.6 μg L−1, with repeatabilities (RSD, n = 7) of 7.3%, 6.9% and 8.1% respectively for 10 mg L−1 samples. The proposed method was successfully applied to the characterization of AuNP size and concentration in aqueous test samples. PMID:27080702

  13. Highly sensitive trivalent copper chelate-luminol chemiluminescence system for capillary electrophoresis detection of epinephrine in the urine of smoker.

    PubMed

    Li, Tao; Wang, Zuorong; Xie, Haoyue; Fu, Zhifeng

    2012-12-12

    Epinephrine (EP) is one of the most important neurotransmitters and hormones. Some previous literatures show that there is a close relation between its release and smoking. To compare the levels of EP in urines of smokers and nonsmokers, a sensitive chemiluminescence (CL) system, luminol-diperiodatocuprate (III) (K(5)[Cu(HIO(6))(2)], DPC), has been developed and validated for the determination of EP after CE separation. The DPC-luminol-EP CL reaction showed very intensive emission and fast kinetic characteristics, thus led to a high sensitivity in the flow-through detection mode for capillary electrophoresis. With the peak height as a quantitative parameter, the relative CL intensity was linear with the EP concentration in the range of 2.0-400ng/mL, with a limit of detection of 0.82ng/mL (S/N=3). The reproducibility was assessed by intra- and inter-day relative standard deviations (RSDs) for 11 replicate determinations of EP standard samples at low, medium and high concentrations. The intra- and inter-day RSDs for CL signals were 5.5%-6.6% and 6.1%-7.5%, respectively, and those for migration times were 3.4%-5.8% and 4.3%-6.3%, respectively. The presented method was successfully applied to the determination of EP in EP injection and urine samples of smokers and nonsmokers. The recovery test results for urine samples ranged from 86.5 to 112.0%, which demonstrated the reliability of this method. The results for urine sample detection indicate that the average level of EP in the urines of the smoker group is obviously higher than that in the urines of the nonsmoker group, which may demonstrate that smoking can stimulate the release of EP in human body. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Enhancement of electrogenerated chemiluminescence of luminol by ascorbic acid at gold nanoparticle/graphene modified glassy carbon electrode.

    PubMed

    Dong, Yongping; Gao, Tingting; Zhou, Ying; Chu, Xiangfeng; Wang, Chengming

    2015-01-05

    Gold nanoparticle/graphene (GNP/GR) nanocomposite was one-pot synthesized from water soluble graphene and HAuCl₄ by hydrothermal method and characterized by TEM, Raman spectroscopy, XRD, XPS, UV-vis spectroscopy, and electrochemical impedance spectroscopy (EIS). Electrogenerated chemiluminescence (ECL) of luminol was investigated at the GNP/GR modified glassy carbon electrode (GNP/GR/GCE) and the GNP modified glassy carbon electrode (GNP/GCE) in aqueous solution respectively. The results revealed that one strong anodic ECL peak could be observed at ∼0.8 V at two modified electrodes compared with that at the bare electrode. The intensity of the anodic ECL at the GNP/GR/GCE is weaker than that at the GNP/GCE, which should be due to the synergic effect of the enhancing effect of gold nanoparticles and the inhibiting effect of graphene on anodic luminol ECL. One strong cathodic ECL peak located at ∼-0.8 V could be observed at the GNP/GR/GCE but not at the GNP/GCE, which should be result from the adsorbed oxygen at the graphene film. In the presence of ascorbic acid, the anodic ECL at the GNP/GR/GCE was enhanced more than 8-times, which is more apparent than that at the GNP/GCE. Whereas, the cathodic ECL peak was seriously inhibited at the GNP/GR/GCE. The enhanced ECL intensity at the GNP/GR/GCE varied linearly with the logarithm of ascorbic acid concentration in the range of 1.0 × 10(-8) to 1.0 × 10(-6)mol L(-1) with a detection limit of 1.0 × 10(-9) mol L(-1). The possible ECL mechanism was also discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Simultaneous Determination of Size and Quantification of Gold Nanoparticles by Direct Coupling Thin layer Chromatography with Catalyzed Luminol Chemiluminescence.

    PubMed

    Yan, Neng; Zhu, Zhenli; He, Dong; Jin, Lanlan; Zheng, Hongtao; Hu, Shenghong

    2016-04-15

    The increasing use of metal-based nanoparticle products has raised concerns in particular for the aquatic environment and thus the quantification of such nanomaterials released from products should be determined to assess their environmental risks. In this study, a simple, rapid and sensitive method for the determination of size and mass concentration of gold nanoparticles (AuNPs) in aqueous suspension was established by direct coupling of thin layer chromatography (TLC) with catalyzed luminol-H2O2 chemiluminescence (CL) detection. For this purpose, a moving stage was constructed to scan the chemiluminescence signal from TLC separated AuNPs. The proposed TLC-CL method allows the quantification of differently sized AuNPs (13 nm, 41 nm and 100 nm) contained in a mixture. Various experimental parameters affecting the characterization of AuNPs, such as the concentration of H2O2, the concentration and pH of the luminol solution, and the size of the spectrometer aperture were investigated. Under optimal conditions, the detection limits for AuNP size fractions of 13 nm, 41 nm and 100 nm were 38.4 μg L(-1), 35.9 μg L(-1) and 39.6 μg L(-1), with repeatabilities (RSD, n = 7) of 7.3%, 6.9% and 8.1% respectively for 10 mg L(-1) samples. The proposed method was successfully applied to the characterization of AuNP size and concentration in aqueous test samples.

  16. A luminol electrochemiluminescence aptasensor based on glucose oxidase modified gold nanoparticles for measurement of platelet-derived growth factor BB.

    PubMed

    Zhang, Jing-Jing; Cao, Jun-Tao; Shi, Gui-Fang; Huang, Ke-Jing; Liu, Yan-Ming; Ren, Shu-Wei

    2015-01-01

    A sandwich-type luminol electrochemiluminescence (ECL) aptasensor for highly sensitive and selective detection of platelet-derived growth factor BB (PDGF-BB) is fabricated. For this proposed ECL aptasensor, a multilayered AuNPs-electrochemically reduced graphene (AuNPs-EG) nanocomposite film was formed on the GCE surface as the base of the aptasensor through a co-electrodeposition method. The AuNPs-EG composites possess high conductivity to promote the electron transfer at the electrode interface and good biocompatibility and large surface area to capture large amounts of primary aptamer (Apt1), thus amplifying the detection response. Moreover, glucose oxidase (GOD) functionalized AuNPs labeled secondary aptamer (GOD-Apt2-AuNPs) was designed as the signal probe for the sandwiched aptasensor. Enhanced sensitivity was obtained by in situ generation of H2O2 from reaction between GOD and glucose and the excellent catalytic behavior of AuNPs to the ECL of the luminol-H2O2 system. Under the optimal conditions, the as-prepared ECL aptasensor exhibited excellent analytical property for the detection of PDGF-BB in the range from 1.0×10(-13) to 5.0×10(-10) mol L(-1) with a detection limit of 1.7×10(-14) mol L(-1) (S/N=3). The application of the present protocol was demonstrated by analyzing PDGF-BB in human serum and human urine samples with the recoveries from 85.0% to 110%. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Enhancement of electrogenerated chemiluminescence of luminol by ascorbic acid at gold nanoparticle/graphene modified glassy carbon electrode

    NASA Astrophysics Data System (ADS)

    Dong, Yongping; Gao, Tingting; Zhou, Ying; Chu, Xiangfeng; Wang, Chengming

    2015-01-01

    Gold nanoparticle/graphene (GNP/GR) nanocomposite was one-pot synthesized from water soluble graphene and HAuCl4 by hydrothermal method and characterized by TEM, Raman spectroscopy, XRD, XPS, UV-vis spectroscopy, and electrochemical impedance spectroscopy (EIS). Electrogenerated chemiluminescence (ECL) of luminol was investigated at the GNP/GR modified glassy carbon electrode (GNP/GR/GCE) and the GNP modified glassy carbon electrode (GNP/GCE) in aqueous solution respectively. The results revealed that one strong anodic ECL peak could be observed at ∼0.8 V at two modified electrodes compared with that at the bare electrode. The intensity of the anodic ECL at the GNP/GR/GCE is weaker than that at the GNP/GCE, which should be due to the synergic effect of the enhancing effect of gold nanoparticles and the inhibiting effect of graphene on anodic luminol ECL. One strong cathodic ECL peak located at ∼-0.8 V could be observed at the GNP/GR/GCE but not at the GNP/GCE, which should be result from the adsorbed oxygen at the graphene film. In the presence of ascorbic acid, the anodic ECL at the GNP/GR/GCE was enhanced more than 8-times, which is more apparent than that at the GNP/GCE. Whereas, the cathodic ECL peak was seriously inhibited at the GNP/GR/GCE. The enhanced ECL intensity at the GNP/GR/GCE varied linearly with the logarithm of ascorbic acid concentration in the range of 1.0 × 10-8 to 1.0 × 10-6 mol L-1 with a detection limit of 1.0 × 10-9 mol L-1. The possible ECL mechanism was also discussed.

  18. Simultaneous Determination of Size and Quantification of Gold Nanoparticles by Direct Coupling Thin layer Chromatography with Catalyzed Luminol Chemiluminescence

    NASA Astrophysics Data System (ADS)

    Yan, Neng; Zhu, Zhenli; He, Dong; Jin, Lanlan; Zheng, Hongtao; Hu, Shenghong

    2016-04-01

    The increasing use of metal-based nanoparticle products has raised concerns in particular for the aquatic environment and thus the quantification of such nanomaterials released from products should be determined to assess their environmental risks. In this study, a simple, rapid and sensitive method for the determination of size and mass concentration of gold nanoparticles (AuNPs) in aqueous suspension was established by direct coupling of thin layer chromatography (TLC) with catalyzed luminol-H2O2 chemiluminescence (CL) detection. For this purpose, a moving stage was constructed to scan the chemiluminescence signal from TLC separated AuNPs. The proposed TLC-CL method allows the quantification of differently sized AuNPs (13 nm, 41 nm and 100 nm) contained in a mixture. Various experimental parameters affecting the characterization of AuNPs, such as the concentration of H2O2, the concentration and pH of the luminol solution, and the size of the spectrometer aperture were investigated. Under optimal conditions, the detection limits for AuNP size fractions of 13 nm, 41 nm and 100 nm were 38.4 μg L-1, 35.9 μg L-1 and 39.6 μg L-1, with repeatabilities (RSD, n = 7) of 7.3%, 6.9% and 8.1% respectively for 10 mg L-1 samples. The proposed method was successfully applied to the characterization of AuNP size and concentration in aqueous test samples.

  19. TAILORING INORGANIC SORBENTS FOR SRS STRONTIUM AND ACTINIDE SEPARATIONS: OPTIMIZED MONOSODIUM TITANATE PHASE II FINAL REPORT

    SciTech Connect

    Hobbs, D; Thomas Peters, T; Michael Poirier, M; Mark Barnes, M; Major Thompson, M; Samuel Fink, S

    2007-06-29

    This document provides a final report of Phase II testing activities for the development of a modified monosodium titanate (MST) that exhibits improved strontium and actinide removal characteristics compared to the baseline MST material. The activities included determining the key synthesis conditions for preparation of the modified MST, preparation of the modified MST at a larger scale by a commercial vendor, demonstration of the strontium and actinide removal characteristics with actual tank waste supernate and measurement of filtration characteristics. Key findings and conclusions include the following. Testing evaluated three synthetic methods and eleven process parameters for the optimum synthesis conditions for the preparation on an improved form of MST. We selected the post synthesis method (Method 3) for continued development based on overall sorbate removal performance. We successfully prepared three batches of the modified MST using Method 3 procedure at a 25-gram scale. The laboratory prepared modified MST exhibited increased sorption kinetics with simulated and actual waste solutions and similar filtration characteristics to the baseline MST. Characterization of the modified MST indicated that the post synthesis treatment did not significantly alter the particle size distribution, but did significantly increase the surface area and porosity compared to the original MST. Testing indicated that the modified MST exhibits reduced affinity for uranium compared to the baseline MST, reducing risk of fissile loading. Shelf-life testing indicated no change in strontium and actinide performance removal after storing the modified MST for 12-months at ambient laboratory temperature. The material releases oxygen during the synthesis and continues to offgas after the synthesis at a rapidly diminishing rate until below a measurable rate after 4 months. Optima Chemical Group LLC prepared a 15-kilogram batch of the modified MST using the post synthesis procedure (Method

  20. Monosodium glutamate and sweet taste: generalization of conditioned taste aversion between glutamate and sweet stimuli in rats.

    PubMed

    Heyer, B R; Taylor-Burds, C C; Tran, L H; Delay, E R

    2003-09-01

    Even though monosodium glutamate (MSG) is a prototypical umami substance, previous studies reported that a conditioned taste aversion (CTA) to MSG, mixed with amiloride to block the taste of sodium, generalizes to sucrose. These findings suggest that the taste of glutamate mimics the taste of sucrose and raise the question of whether glutamate has a broadly tuned sweet taste component. To test this hypothesis, CTA experiments were conducted to test for generalization between MSG and several sweet stimuli: sucrose, glucose, maltose, saccharin and SC-45647. Strong bidirectional generalization was seen between MSG mixed with amiloride and sucrose, glucose, saccharin and SC-45647. Weak generalization was seen between MSG and maltose, and sucrose and maltose. None of the CTAs generalized to NMDA. These findings support the hypothesis that the taste of MSG has broadly tuned, sweet-like characteristics, possibly due to the convergence of afferent signals for MSG, natural sugars and artificial sweeteners.

  1. A new automated approach to determine monosodium glutamate in dehydrated broths by using the flow-batch methodology.

    PubMed

    Acebal, Carolina C; Insausti, Matías; Pistonesi, Marcelo F; Lista, Adriana G; Band, Beatriz S Fernández

    2010-04-15

    The advantages of the flow-batch methodology were exploited to implement a simple system with nephelometric detection for the determination of monosodium glutamate (MSG) in food samples. The method is based on the inhibitory effect of the MSG over the crystallization of L-lysine in an isopropanol/acetone mixture. The calibration curve was prepared on-line. The method was linear over the range of 2.8 x 10(-3) to 1.1 x 10(-2)gL(-1) and a detection limit of 9.7 x 10(-5)gL(-1) was achieved. It was successfully applied to determine the MSG concentration in food samples, without a previous treatment. A recovery study was carried out on real samples and the percentages were between 98 and 106%. (c) 2009 Elsevier B.V. All rights reserved.

  2. The feasibility of using complex wastewater from a monosodium glutamate factory to cultivate Spirulina subsalsa and accumulate biochemical composition.

    PubMed

    Jiang, Liqun; Pei, Haiyan; Hu, Wenrong; Ji, Yan; Han, Lin; Ma, Guixia

    2015-03-01

    This paper is mainly observations on the growth and biomass accumulation of Spirulina subsalsa in modified Zarrouk medium supplemented with complex wastewater (CW, from a monosodium glutamate factory) in different concentrations. High ammonia in 75% and 100% CW inhibits algae growth, but maximum biomass production (2.86mgL(-1)) was obtained in 25% CW (concentration of CW in medium was 25%). Different CW concentration promoted biomass composition accumulation at different degrees, 41% of protein content in 25% CW and 18% of carbohydrate in 50% CW. In terms of economy, a concentration of 25% CW was suitable for protein production and 50% for lipid and carbohydrate production. These results suggested that CW is a feasible replacement in part for cultivation of S. subsalsa to economize input of water and nutrients.

  3. Monosodium glutamate-associated alterations in open field, anxiety-related and conditioned place preference behaviours in mice.

    PubMed

    Onaolapo, Olakunle James; Aremu, Olaleye Samuel; Onaolapo, Adejoke Yetunde

    2017-03-29

    The present study investigated changes in behaviour associated with oral monosodium glutamate (a flavouring agent), using the open field, elevated plus maze and conditioned place preference (CPP) paradigms, respectively. Mice were assigned to two groups for CPP [monosodium glutamate (MSG)-naïve (n = 40) and MSG-pretreated (n = 40)] and two groups for open field (OF) and elevated plus maze (EPM) tests [n = 40 each], respectively. Animals in respective groups were then divided into four subgroups (n = 10) (vehicle or MSG (80, 160 and 320 mg/kg)). MSG-naïve mice were observed in the CPP box in three phases (pre-conditioning, conditioning and post-conditioning). Mice were conditioned to MSG or an equivalent volume of saline. The MSG pretreatment group received vehicle or respective doses of MSG daily for 21 days, prior to conditioning. Mice in the OF or EPM groups received vehicle or doses of MSG (orally) for 21 days, at 10 ml/kg. Open field or EPM behaviours were assessed on days 1 and 21. At the end of the experiments, mice in the OF groups were sacrificed and brain homogenates used to assay glutamate and glutamine. Results showed that administration of MSG was associated with a decrease in rearing, dose-related mixed horizontal locomotor, grooming and anxiety-related response and an increase in brain glutamate/glutamine levels. Following exposure to the CPP paradigm, MSG-naïve and MSG-pretreated mice both showed 'drug-paired' chamber preference. The study concluded that MSG (at the administered doses) was associated with changes in open field activities, anxiety-related behaviours and brain glutamate/glutamine levels; its ingestion also probably leads to a stimulation of the brain reward system.

  4. Determination of phenol by flow-injection with chemiluminescence detection based on the hemin-catalysed luminol-hydrogen peroxide reaction

    NASA Astrophysics Data System (ADS)

    Liu, Wenwen; Cao, Wei; Liu, Weihua; Du, Kang; Gong, Pixue

    2012-01-01

    This study established a novel flow injection (FI) methodology for the determination of phenol in aqueous samples based on luminol chemiluminescence (CL) detection. The method was based on the inhibition that phenol caused on the hemin-catalysed chemiluminescence reaction between luminol and hydrogen peroxide in alkaline solution. Optimum conditions and possible mechanisms have been investigated. The linear range was 2.0 × 10 -9 to 4.0 × 10 -7 g mL -1 for phenol. The proposed method is sensitive with a detection limit of 4.0 × 10 -10 g mL -1. The relative standard deviation for 11 measurements was 2.3% for 1.0 × 10 -7g mL -1 phenol. The method was applied for the determination of phenol in waste water samples. The results obtained compared well with those by an official method.

  5. Effect of oxidatively modified and non-modified human serum albumin on luminol-dependent chemiluminescence of human peripheral blood leukocytes stimulated with opsonized zymosan.

    PubMed

    Piryazev, A P; Azizova, A P; Aseichev, A V; Sergienko, V I

    2014-07-01

    We studied the effects of native and oxidized human serum albumin on luminol-dependent chemiluminescence of human peripheral blood leukocytes stimulated with opsonized zymosan. Human serum albumin was added simultaneously with opsonized zymosan at the beginning of the chemiluminescent reaction. Otherwise, leukocytes were incubated with human serum albumin at 37°C for various periods before addition of opsonized zymosan. Oxidized human serum albumin was obtained by the method of metal-catalyzed oxidation. In control to non-modified albumin, oxidized albumin produced an inhibitory effect on luminol-dependent chemiluminescence of leukocytes. These changes were observed in experiments with addition of oxidized albumin at the beginning of a chemiluminescent reaction and after incubation of study agent with cells.

  6. Co-metal-organic-frameworks with pure uniform crystal morphology prepared via Co2 + exchange-mediated transformation from Zn-metallogels for luminol catalysed chemiluminescence

    NASA Astrophysics Data System (ADS)

    Tang, Xue Qian; Xiao, Bo Wen; Li, Chun Mei; Wang, Dong Mei; Huang, Cheng Zhi; Li, Yuan Fang

    2017-03-01

    Cation exchange-mediated transformation from Zn-metallogels (MOGs), which was a mild facile strategy relative to the demanding hydrothermal method, was employed to develop Co2 + metal-organic frameworks (Co-MOFs) at room temperature. The obtained Co-MOFs was of uniform octahedral morphology and possessed high activity to catalyze luminol chemiluminescence without extra oxidants. By adding cysteine, the CL emission of luminol-Co-MOFs system was further enhanced. Based on this phenomenon, Co-MOFs was utilized to build a practical sensing platform for cysteine determination. Under the optimized conditions, the relative CL intensity (ΔI) was proportional to the concentration of cysteine in the range of 2-10 μM, and the detection limit was 0.49 μM (3S/N). Moreover, the established method was applied to the determination of cysteine in commercially available pharmaceutical injections.

  7. In vitro evaluation of opsonic and cellular granulocyte function by luminol-dependent chemiluminescence: utility in patients with severe neutropenia and cellular deficiency states.

    PubMed Central

    Stevens, P; Winston, D J; Van Dyke, K

    1978-01-01

    Actively phagocytizing polymorphonuclear leukocytes (PMN) emit light or chemiluminescence (CL) which has been shown to be linked to the oxidative activity of the PMN. The measurement of CL has been demonstrated to be a useful tool for the in vitro assessment of intracellular and opsonophagocytic function of PMN. We have increased the sensitivity of the CL measurement by the addition of luminol to the in vitro reaction of PMN, bacteria, and serum. The presence of luminol, which can be oxidized to emit light, amplifies the detection of CL and PMN cellular activity. This amplification effectively reduces the number of PMN that are necessary for assessment of PMN function from 1 x 10(7) to as low as 2 x 10(4) PMN/assay and permits the evaluation of PMN function in severely neutropenic patients (100 PMN/mm3) in whom cellular PMN function has been heretofore extremely difficult to assess by other methodology. When this luminol-dependent CL method was used, three of eight neutropenic leukemic patients with gram-negative septicemia were found to have deficient opsonic activity and/or increased or depressed cellular oxidative activity. Because the initial slope of CL is dependent on the amount of serum and heat-labile factors, this method can also be used effectively as a simple technique for the analysis of specific rates of opsonophagocytosis of various microorganisms. Additionally, this method can detect the cellular PMN abnormalities of chronic granulomatous disease and myeloperoxidase deficiency. The luminol-dependent CL method is a simple, sensitive, reproducible technique that provides useful information about PMN metabolic activity, particularly in studies in which the number of PMN is limited. PMID:215546

  8. Ultrasensitive luminol electrochemiluminescence for protein detection based on in situ generated hydrogen peroxide as coreactant with glucose oxidase anchored AuNPs@MWCNTs labeling.

    PubMed

    Cao, Yaling; Yuan, Ruo; Chai, Yaqin; Mao, Li; Niu, Huan; Liu, Huijing; Zhuo, Ying

    2012-01-15

    In this study, an ultrasensitive luminol electrochemiluminescence (ECL) immunosensor was constructed using carboxyl group functionalized multi-walled carbon nanotubes (MWCNTs) as platform and glucose oxidase (GOD) supported on Au nanoparticles (AuNPs) decorated MWCNTs (AuNPs@MWCNTs-GOD) as labels. Firstly, using poly(ethylenimine) (PEI) as linkage reagents, AuNPs@MWCNTs were prepared and introduced for binding of the secondary antibody (Ab(2)) and glucose oxidase (GOD) with high loading amount and good biological activity due to the improved surface area of AuNPs@MWCNTs and excellent biocompatibility of AuNPs. Then the GOD and Ab(2) labeled AuNPs@MWCNTs were linked to the electrode surface via sandwich immunoreactions. These localized GOD and AuNPs amplified luminol ECL signals dramatically, which was achieved by efficient catalysis of the GOD and AuNPs towards the oxidation of glucose to in situ generate improved amount of hydrogen peroxide (H(2)O(2)) as coreactant and the enhancement of AuNPs to the ECL reaction of luminol-H(2)O(2). The experimental results demonstrated that the proposed immunosensor exhibited sensitive and stable response for the detection of α-1-fetoprotein (AFP), ranging from 0.0001 to 80 ng mL(-1) with a limit of detection down to 0.03 pg mL(-1) (S/N=3). With excellent stability, sensitivity, selectivity and simplicity, the proposed luminol ECL immunosensor showed great potential in clinical applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Simultaneous quantification of catecholamines in rat brain by high-performance liquid chromatography with on-line gold nanoparticle-catalyzed luminol chemiluminescence detection.

    PubMed

    Mu, Chunlei; Zhang, Qi; Wu, Dong; Zhang, Yunjing; Zhang, Qunlin

    2015-01-01

    A new method based on high-performance liquid chromatography (HPLC) coupled with on-line gold nanoparticle-catalyzed luminol chemiluminescence (CL) detection was developed for the simultaneous quantitation of catecholamines in rat brain. In the present CL system, gold nanoparticles were produced by the on-line reaction of H2 O2 , NaHCO3 -Na2 CO3 (buffer solution of luminol) and HAuCl4. Norepinephrine (NE), epinephrine (EP) and dopamine (DA) could strongly enhance the CL signal of the on-line gold nanoparticle-catalyzed luminol system. The UV-visible absorption spectra and transmission electron microscopy studies were carried out, and the CL enhancement mechanism was proposed. Catecholamines promoted the on-line formation of more gold nanoparticles, which better catalyzed the luminol-H2 O2 CL reaction. The good separation of NE, EP and DA was achieved with isocratic elution using a mixture of methanol and 0.2% aqueous phosphoric acid (5:95, v/v) within 8.5 min. Under the optimized conditions, the detection limits, defined as a signal-to-noise ratio of 3, were in the range of 1.32-1.90 ng/mL, corresponding to 26.4-38.0 pg for 20 μL sample injection. The recoveries of catecholamines added to rat brain sample were >94.6%, with the precisions <5.5%. The validated HPLC-CL method was successfully applied to determine NE and DA in rat brain without prior sample purification. Copyright © 2014 John Wiley & Sons, Ltd.

  10. [Action of Combined Magnetic Fields with a Very Weak Low-frequency Alternating Component on Luminol-dependent Chemiluminescence in Mammalian Blood].

    PubMed

    Novikov, V V; Yablokova, E N; Fesenko, E E

    2015-01-01

    It is shown that the exposure of heparinized venous human blood diluted in phosphate buffer saline to extremely weak alternating magnetic fields of the ultralow-frequency (1 Hz, 600 nT; 4.4 Hz, 100 nT; 16.5 Hz, 160 nT) in combination with a collinear static magnetic field of 42 microT at physiological temperatures, causes a sharp 3-4 fold increase in its chemiluminescence after addition of luminol.

  11. Postmortem interval of skeletal remains through the detection of intraosseal hemin traces. A comparison of UV-fluorescence, luminol, Hexagon-OBTI®, and Combur® tests.

    PubMed

    Ramsthaler, Frank; Ebach, Sarah C; Birngruber, Christoph G; Verhoff, Marcel A

    2011-06-15

    With the goal of obtaining additional practically applicable methods for estimating the PMI of skeletal remains, 39 samples of human and 5 samples of domestic animal long bones with known PMI (PMI=1 to approximately 2000 years) were tested with two established methods (UV-fluorescence of a freshly sawn cross-section and the luminol test) and two screening tests (Hexagon-OBTI® test and Combur® test) that were being tried out in this context for the first time. The hypothesis underlying this experiment was the supposition that the PMI-related chemiluminescence of the luminol reaction for bone is based on the presence of persisting hemin from hemoglobin molecules in bone. Our results showed that lack of luminescence and reduced UV-fluorescence were more meaningful results for estimating PMI and excluding forensic relevance than a positive luminol reaction or strong UV-fluorescence, as both of the latter findings revealed the limitations of these methods in this particular context. Particularly for cases showing a positive luminol reaction, the use of additional absolute dating methods may be indicated. Against our expectations, both the Combur® test strips and the Hexagon-OBTI® test, which were both devised to demonstrate blood, delivered negative results for all samples. They are thus not suitable for estimating the PMI of skeletal remains. Future research will be necessary to elucidate whether the negative results obtained for these tests may be due to the poor solubility of potentially present hemoglobin or hemoglobin breakdown products in the Tris buffer used in this experiment.

  12. Chemiluminescence determination of moxifloxacin in pharmaceutical and biological samples based on its enhancing effect of the luminol-ferricyanide system using a microfluidic chip.

    PubMed

    Suh, Yeoun Suk; Kamruzzaman, Mohammad; Alam, Al-Mahmnur; Lee, Sang Hak; Kim, Young Ho; Kim, Gyu-Man; Dang, Trung Dung

    2014-05-01

    A sensitive determination of a synthetic fluoroquinolone antibacterial agent, moxifloxacin (MOX), by an enhanced chemiluminescence (CL) method using a microfluidic chip is described. The microfluidic chip was fabricated by a soft-lithographic procedure using polydimethyl siloxane (PDMS). The fabricated PDMS microfluidic chip had three-inlet microchannels for introducing the sample, chemiluminescent reagent and oxidant, and a 500 µm wide, 250 µm deep and 82 mm long microchannel. An enhanced CL system, luminol-ferricyanide, was adopted to analyze the MOX concentration in a sample solution. CL light was emitted continuously after mixing luminol and ferricyanide in the presence of MOX on the PDMS microfluidic chip. The amount of MOX in the luminol-ferricyanide system influenced the intensity of the CL light. The linear range of MOX concentration was 0.14-55.0 ng/mL with a correlation coefficient of 0.9992. The limit of detection (LOD) and limit of quantification (LOQ) were 0.06 and 0.2 ng/mL respectively. The presented method afforded good reproducibility, with a relative standard deviation (RSD) of 1.05% for 10 ng/mL of MOX, and has been successfully applied for the determination of MOX in pharmaceutical and biological samples.

  13. A stopped-flow study of the dual chemiluminescence for the luminol-KIO4-Mn(2+) system in strong alkaline solutions.

    PubMed

    Huang, Tsung-Yuan; Lin, Wann-Yin

    2011-01-01

    A novel phenomenon of dual chemiluminescence (CL) was observed for the KIO4-luminol-Mn(2+) system in strong alkaline solutions using the stopped-flow technique. Scavenging study of the reactive oxygen species (ROS) suggested that the two CL peaks originated from different CL pathways precipated by distinct ROS (O2(-) and •OH for the first peak, mainly 1O2 for the second peak). Generation of these ROS at different time intervals from the reactions involving IO4(-), O2, and Mn(2+) and their subsequent reactions with luminol induced the intense CL emission. The relative intensity of the two CL peaks can be tuned over a wide range by varying the concentrations of Mn(2-), luminol and KIO4. Because of the involvement of different ROS in each pathway, the two CL peaks could respond quite differently to various substances. Moreover, variation of the intensity ratio of the two CL peaks altered the relative proportions of the corresponding ROS, thereby changing their responses to a given substance. The dual CL emission acts like a pair of tunable probes and it is believed that this CL system has great potential in analytical applications.

  14. Trivalent copper chelate-luminol chemiluminescence system for highly sensitive CE detection of dopamine in biological sample after clean-up using SPE.

    PubMed

    Wang, Lin; Liu, Ying; Xie, Haoyue; Fu, Zhifeng

    2012-06-01

    A transition metal chelate unstable at a high oxidation state, diperiodatocuprate (III) (K₅[Cu(HIO₆)₂], DPC), was synthesized and applied in the luminol-based chemiluminescence (CL) system for highly sensitive CE end-column detection of dopamine (DA). This method was based on the fact that DA enhanced the CL emission resulting from the reaction between luminol and DPC in alkaline medium. The DPC-luminol-DA CL system showed very intensive emission and very fast kinetic characteristics, thus resulting in a high sensitivity in flow-through detection mode for CE. Under optimal conditions, the linear range was 1.0 × 10⁻⁸-5.0 × 10⁻⁵ g/mL (R² = 0.9984) with a limit of detection of 6.0 × 10⁻⁹ g/mL (S/N = 3). The RSDs of the peak height and the migration time were about 4.2 and 2.4% for a standard sample at 3.0 × 10⁻⁶ g/mL (n = 5), respectively. The presented method has been successfully used for the determination of DA in commercial preparation and human urine samples after clean-up using SPE.

  15. Supramolecular assembly and nanostructures of a series of luminol derivatives with aromatic/alkyl substituted groups in Langmuir-Blodgett films.

    PubMed

    Jiao, Tifeng; Xing, Yuanyuan; Zhang, Qingrui; Zhang, Li; Liu, Minghua; Zhou, Jingxin; Gao, Faming

    2014-06-01

    A series of functional luminol derivatives with aromatic and alkyl substituted groups has been designed and synthesized from the reaction of the corresponding chloride precursors with luminol. These compounds can be spread on water surface to form stable Langmuir films at the air-water interface. It has been found that UV and IR spectra confirmed the characteristic aromatic segment, imide group, and aromatic/alkyl substituted groups. In addition, for the interfacial assembly process of compounds with alkyl substituted groups, there are obvious spectral changes for the alkyl chains. AFM results indicated that various different aggregated domains may be fabricated in the transferred LB films. For all cases, the substituted groups in molecular structures have an important effect in regulating the aggregation mode and spectral changes in organized molecular films. The present results showed that the modified luminol derivatives may have potential application in functional material fields such as ECL sensor, which may give some insight to study the relationship between the molecular structures and supramolecular aggregation of amphiphiles in organized molecular films.

  16. Electrochemiluminescent disposable cholesterol biosensor based on avidin-biotin assembling with the electroformed luminescent conducting polymer poly(luminol-biotinylated pyrrole).

    PubMed

    Ballesta-Claver, J; Ametis-Cabello, J; Morales-Sanfrutos, J; Megía-Fernández, A; Valencia-Mirón, M C; Santoyo-González, F; Capitán-Vallvey, L F

    2012-11-19

    An electrochemiluminescent cholesterol disposable biosensor has been prepared by the formation of assembled layers on gold screen-printed cells. The detection layer is based on the electro-formation of new luminol copolymers with different synthesized biotinylated pyrroles prepared by click-chemistry, offering a new transduction layer with new electroluminescent properties on biosensors. The electrochemiluminescence (ECL) luminol copolymers are electroformed by cyclic voltammetry (five cycles) at pH 7.0 uses a10(-3)M biotinylated pyrrole-luminol ratio of 1:10 in PBS buffer. With respect to the recognition layer, cholesterol oxidase was biotinylated by incubation with biotin vinyl sulfone, and immobilized on the copolymer by avidin-biotin interaction. The analytical signal of the biosensor is the ECL enzymatic initial rate working in chronoamperometric mode at 0.5V excitation potential with 10s between pulses at pH 9.5. The disposable device offers a cholesterol linear range from 1.5×10(-5)M to 8.0×10(-4)M with a limit of detection of 1.47×10(-5)M and accuracy of 7.9% for 9.0×10(-5)M and 14.1% for 2.0×10(-4)M, (n=5). Satisfactory results were obtained for cholesterol determination in serum samples compared to a reference procedure.

  17. TAILORING INORGANIC SORBENTS FOR SRS STRONTIUM AND ACTINIDE SEPARATIONS: MODIFIED MONOSODIUM TITANATE PHASE III FINAL REPORT

    SciTech Connect

    Taylor-Pashow, K.; Hobbs, D.

    2010-09-01

    This document provides a final report of Phase III testing activities for the development of modified monosodium titanate (mMST), which exhibits improved strontium and actinide removal characteristics compared to the baseline MST material. The activities included characterization of the crystalline phases present at varying temperatures, solids settling characteristics, quantification of the peroxide content; evaluation of the post-synthesis gas release under different conditions; the extent of desorption of {sup 85}Sr, Np, and Pu under washing conditions; and the effects of age and radiation on the performance of the mMST. Key findings and conclusions include the following. The peroxide content of several mMST samples was determined using iodometric titration. The peroxide content was found to decrease with age or upon extended exposure to elevated temperature. A loss of peroxide was also measured after exposure of the material to an alkaline salt solution similar in composition to the simulated waste solution. To determine if the loss of peroxide with age affects the performance of the material, Sr and actinide removal tests were conducted with samples of varying age. The oldest sample (4 years and 8 months) did show lower Sr and Pu removal performance. When compared to the youngest sample tested (1 month), the oldest sample retained only 15% of the DF for Pu. Previous testing with this sample indicated no decrease in Pu removal performance up to an age of 30 months. No loss in Np removal performance was observed for any of the aged samples, and no uptake of uranium occurred at the typical sorbent loading of 0.2 g/L. Additional testing with a uranium only simulant and higher mMST loading (3.0 g/L) indicated a 10% increase of uranium uptake for a sample aged 3 years and 8 months when compared to the results of the same sample measured at an age of 1 year and 5 months. Performance testing with both baseline-MST and mMST that had been irradiated in a gamma source to

  18. Monosodium glutamate, disodium inosinate, disodium guanylate, lysine and taurine improve the sensory quality of fermented cooked sausages with 50% and 75% replacement of NaCl with KCl.

    PubMed

    dos Santos, Bibiana Alves; Campagnol, Paulo Cezar Bastianello; Morgano, Marcelo Antônio; Pollonio, Marise Aparecida Rodrigues

    2014-01-01

    Fermented cooked sausages were produced by replacing 50% and 75% of NaCl with KCl and adding monosodium glutamate, disodium inosinate, disodium guanylate, lysine and taurine. The manufacturing process was monitored by pH and water activity measurements. The sodium and potassium contents of the resulting products were measured. The color values (L*, a* and b*), texture profiles and sensory profiles were also examined. Replacing 50% and 75% NaCl with KCl depreciated the sensory quality of the products. The reformulated sausages containing monosodium glutamate combined with lysine, taurine, disodium inosinate and disodium guanylate masked the undesirable sensory attributes associated with the replacement of 50% and 75% NaCl with KCl, allowing the production of fermented cooked sausages with good sensory acceptance and approximately 68% sodium reduction.

  19. A chelate complex-enhanced luminol system for selective determination of Co(II), Fe(II) and Cr(III).

    PubMed

    Kim, Kyung Min; Kim, Young Ho; Oh, Sang-Hyub; Lee, Sang Hak

    2013-01-01

    A determination method for Co(II), Fe(II) and Cr(III) ions by luminol-H2 O2 system using chelating reagents is presented. A metal ion-chelating ligand complex with a Co(II) ion and a chelating reagent like ethylenediaminetetraacetic acid (EDTA) produced highly enhanced chemiluminescence (CL) intensity as well as longer lifetime in the luminol-H2 O2 system compared to metals that exist as free ions. Whereas free Cu(II) and Pb(II) ions had a strong catalytic effect on the luminol-H2 O2 system, significantly, the complexes of Cu(II) and Pb(II) with chelating reagents lost their catalytic activity due to the chelating reagents acting as masking agents. Based on the observed phenomenon, it was possible to determine Co(II), Fe(II) and Cr(III) ions with enhanced sensitivity and selectivity using the chelating reagents of the luminol-H2 O2 system. The effects of ligand, H2 O2 concentration, pH, buffer solution and concentrations of chelating reagents on CL intensity of the luminol-H2 O2 system were investigated and optimized for the determination of Co(II), Fe(II) and Cr(III) ions. Under optimized conditions, the calibration curve of metal ions was linear over the range of 2.0 × 10(-8) to 2.0 × 10(-5) M for Co(II), 1.0 × 10(-7) to 2.0 × 10(-5) M for Fe (II) and 2.0 × 10(-7) to 1.0 × 10(-4) M for Cr(III). Limits of detection (3σ/s) were 1.2 × 10(-8) , 4.0 × 10(-8) and 1.2 × 10(-7) M for Co(II), Fe(II) and Cr(III), respectively. Copyright © 2012 John Wiley & Sons, Ltd.

  20. A new screening method to detect water-soluble antioxidants: acetaminophen (Tylenol) and other phenols react as antioxidants and destroy peroxynitrite-based luminol-dependent chemiluminescence.

    PubMed

    Van Dyke, K; Sacks, M; Qazi, N

    1998-01-01

    This study is based on a simple chemical interaction of peroxynitrite (O = N-O-O-) and luminol, which produces blue light upon oxidation. Since peroxynitrite has a half-life of about 1 s, a drug known as linsidomine (SIN-1) is used as a peroxynitrite generator. Peroxynitrite can oxidize lipids, proteins and nucleic acids. Upon the stimulation of inflammation and/or infection, macrophages and neutrophils can be induced to produce large amounts of peroxynitrite, which can oxidize phenols and sulphhydryl-containing compounds. Therefore, phenols and sulphhydryls eliminate peroxynitrite. This is an example of the Yin-Yang hypothesis e.g. oxidation-reduction. Acetaminophen (Tylenol) can inhibit fever and some types of pain without being a particularly effective anti-inflammatory. Since it is a phenol, it could act as a nitration target for peroxynitrite. Then peroxynitrite, the possible cause of pain and elevated temperature, might be destroyed in the reaction. Acetaminophen is a phenolic compound which produces a clear inhibitory dose-response curve with peroxynitrite in its range of clinical effectiveness. Whether acetaminophen actually works as we suggest is to be proven. Three different types of reaction could decrease the amount of peroxynitrite: (a) interference with base-catalysed opening of the SIN-1 molecule; (b) destruction of one or both substances needed to form it--superoxide and/or nitric oxide; when the SIN-1 degrades to superoxide and nitric oxide, the former may be destroyed by superoxide dismutase (SOD); (c) peroxynitrite may react directly with phenols (mono-, di-, tri- and tetraphenols), possibly by nitration. Nordihydroguaiaretic acid and 2-hydroxyestradiol (catechol estrogen) are potent inhibitors of luminol light emission. Epineprine, isoproterenol, pyrogallol, catechol and ascorbic acid (a classic antioxidant) are all inhibitors of luminol chemiluminescence. Isoproterenol, norepinephrine/and epinephrine first inhibit light but overall stimulate

  1. Real-time measurement of nitric oxide by luminol-hydrogen peroxide reaction in crystalloid perfused rat heart.

    PubMed

    Tsukada, Yayoi; Yasutake, Masahiro; Jia, Dalin; Kusama, Yoshiki; Kishida, Hiroshi; Takano, Teruo; Tsukada, Shingo

    2003-01-17

    The objective of this study was to develop an assay system that allows continuous monitoring of nitric oxide (NO) released from crystalloid perfused hearts. We utilized chemiluminescence reaction between NO and luminol-H(2)O(2) to quantify the NO level in coronary effluent. Isolated rat hearts were subjected to ordinary Langendorff's perfusion, and the right ventricle was cannulated to sample coronary effluent. After equilibration, the coronary flow rate was set constant and the hearts were paced at 300 bpm. Coronary effluent was continuously sampled and mixed with the chemiluminescent probe containing 0.018 mmol/l luminol plus 10 mmol/l H(2)O(2). Chemiluminescence from the mixture of coronary effluent and the probe was continuously measured. NO concentration was calibrated by various concentrations (0.5-400 pmol/l) of standard NO solution. The lower detection limit of NO was 1 pmol/l. Basal NO release from isolated perfused rat heart was 0.41 +/- 0.17 pmol/min/g of heart weight, and that was significantly suppressed by 0.1 mmol/l of L-NAME to 0.18 +/- 0.10 pmol/min/g of heart weight (n = 7). Application of 0.1 and 0.3 micromol/l acetylcholine increased NO level in the coronary effluent, in a concentration-dependent manner, from 6.6 +/- 1.7 in a baseline condition to 16.3 +/- 7.4 and 30.3 +/- 16.1 pmol/l at each peak, respectively. Thrombin at 1 and 10 U/ml also increased NO level from 17.6 +/- 4.3 in control to 35.5 +/- 10.4 and 48.7 +/- 8.7 pmol/l at each peak, respectively (n = 7). Thus, this assay system is applicable to the continuous real-time measurement of NO released from crystalloid perfused hearts, and it may be useful for the study of physiological or pathophysiological role of NO in coronary circulation.

  2. Determination of dissolved Fe(II) in seawater of the western North Pacific with luminol chemiluminescence method

    NASA Astrophysics Data System (ADS)

    Obata, H.; Mase, A.; Gamo, T.; Nishioka, J.; Takeda, S.

    2010-12-01

    Determination of dissolved Fe(II) in seawater of the western North Pacific with luminol chemiluminescence method Hajime Obata, Akira Mase, Toshitaka Gamo (Atmosphere and Ocean Research Institute, University of Tokyo, Japan), Jun Nishioka (Institute of Low Temperature Science, Hokkaido University, Japan), Shigenobu Takeda (Faculty of Fisheries, Nagasaki University, Japan) Speciation of iron in the ocean is now important topics because the bioavailability of iron depends on its chemical form in seawater. However, marine biogeochemical process of Fe(II) has not been fully investigated. In this study, we determined Fe(II) in seawaters using the luminol chemiluminescence method after acidifying the samples to pH 6(Hansard and Landing, 2009). The same samples collected in the western North Pacific were analyzed by the flow chemiluminescence methods with acidification to pH 6 and without acidification. The results with both methods were almost identical. Time variation of Fe(II) in seawater after acidifying the samples to pH 6 were examined in the western North Pacific and the Bering Sea. Within 10 minutes, variations of Fe(II) were small in the open ocean waters, whereas Fe(II) concentrations increased rapidly in surface waters collected in the Bering Sea. The acidification method is not always applicable for seawater samples, especially in the marginal sea. Surface distributions of Fe(II) in the western subarctic North Pacific were investigated by using a continuous clean sampling system for surface waters. The Fe(II) concentrations ranged from <9 to 42 pM, which were lower than those in previous studies (Roy et al., 2008). The variation of Fe(II) probably reflects the photoreduction process of Fe(III), slow oxidation of Fe(II) and differences of Fe(II) concentrations among water masses. In this study, we also examined the oxidation process of Fe(II) in seawater of the western North Pacific and the Bering Sea at some temperatures. The oxidation rates were slower in the

  3. Visual electrochemiluminescence biosensing of aflatoxin M1 based on luminol-functionalized, silver nanoparticle-decorated graphene oxide.

    PubMed

    Khoshfetrat, Seyyed Mehdi; Bagheri, Hasan; Mehrgardi, Masoud A

    2017-09-21

    A sensitive electrochemiluminescence (ECL) aptasensor for aflatoxin M1 (AFM1) detection by a closed bipolar electrode (BPE) array has been introduced. The thiolated AFM1 aptamer was immobilized on gold nanoparticle-coated magnetic Fe3O4 nanoparticles (Apt-GMNPs). Luminol-functionalized silver nanoparticle-decorated graphene oxide (GO-L-AgNPs) participates in π-π interactions with the unpaired bases of the immobilized aptamer (Apt-GMNPs-GO-L-AgNPs). After the Apt-GMNPs-GO-L-AgNPs were introduced to a gold anodic BPE array, the individual electrodes were subjected to different concentrations of AFM1. Upon the interaction of AFM1 with the aptamers, the GO-L-AgNPs detach from the aptamer; the resulting ECL of luminol and H2O2 at the anodic poles is monitored using a photomultiplier tube (PMT) or smartphone, and the images are analyzed using ImageJ software. This process triggers thionine reduction at the cathodic poles. Under the optimal conditions obtained by a face-centered central composite design (FCCD), the PMT-based detection of the BPE-ECL aptasensor exhibit a linear response over a wide dynamic range from 5 to 150ngmL(-1), with a detection limit of 0.01ngmL(-1). Additionally, smartphone-based detection shows a linear relationship between the ECL image gray value and the logarithmic concentration of the AFM1 target over a range of 10-200ngmL(-1), with a detection limit of 0.05ngmL(-1). Furthermore, the BPE-ECL aptasensor was successfully used to detect AFM1 in milk complex media without any serious interferences with reliable reproducibility (average relative standard deviation (RSD = 2.3%)). This smartphone-based detection opens a new horizon for bioanalysis that does not require a trained technician to operate and is a promising technology for point-of-care testing. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Effects of Berberine on NLRP3 and IL-1β Expressions in Monocytic THP-1 Cells with Monosodium Urate Crystals-Induced Inflammation

    PubMed Central

    Wen, Cai-Yu-Zhu; Chen, Zhe; Wang, Yu; Huang, Ying

    2016-01-01

    Background. Urate crystals-induced inflammation is a critical factor during the initiation of gouty arthritis. Berberine is well known for its anti-inflammatory activity. However, the underlying effects of berberine on monosodium urate crystals-induced inflammation remain obscure. Objectives. This study is set to explore the protective effect and mechanism of berberine on monosodium urate crystals-induced inflammation in human monocytic THP-1 cells. Methods. The mRNA levels of NLRP3 and IL-1β were measured by Real-Time PCR, and the protein levels of NLRP3 and IL-1β were determined by ELISA, Western blot, and immunofluorescence. Results. The NLRP3 and IL-1β expressions were significantly increased in model group compared to that in normal group (P < 0.05). Meanwhile, there was significant reduction in the expressions of NLRP3 and IL-1β mRNA in groups 6.25 μM berberine and 25 μM berberine when compared with model group (P < 0.05). Conclusions. Therefore, berberine alleviates monosodium urate crystals-induced inflammation by downregulating NLRP3 and IL-1β expressions. The regulatory effects of berberine may be related to the inactivation of NLRP3 inflammasome. PMID:27689075

  5. Investigations of different chemiluminescent peaks in H2O2-SCN(-)-Cu(2+)-OH(-)-luminol flow system.

    PubMed

    Zhao, Changchun; Zheng, Juhua; Xie, Jingxuan; Liu, Haimiao; Gao, Qingyu

    2011-01-01

    In the H2O2-SCN(-) -Cu(2+)-OH(-)-luminol oscillatory system of chemiluminescence, the effects of the ingredient concentrations, temperature, flow rate and complexing agent on the oscillatory dynamics were investigated in a continuous-flow stirred tank reactor (CSTR). The dynamical structure of two peaks during a period was discussed in detail. By addition of EDTA to the oscillating system, the peak I height decreased sharply while the peak II height was little affected, and the period kept constant. This may be due to the fast reaction between Cu(II) and EDTA and the highly stable complex Cu(II)-EDTA. From the experimental study and mechanism analysis, the chemiluminescent peak I corresponds to Cu(II) → Cu(I) transformation and the peak II corresponds to the Cu(I) → Cu(II) transformation process. The key species involving in the two-transformation process are inferred to be superoxide radical and hydroxyl radical. Copyright © 2010 John Wiley & Sons, Ltd.

  6. Luminol-dependent chemiluminescence of human phagocyte cell lines: comparison between DMSO differentiated PLB 985 and HL 60 cells.

    PubMed

    Ashkenazi, Avraham; Marks, Robert S

    2009-01-01

    The human promyelocytic leukemia HL 60 and PLB 985 cell lines can differentiate into terminally mature neutrophil-like cells via dimethyl sulfoxide (DMSO) induction. In this study the luminol-dependent chemiluminescence (LCL) of both neutrophil-like cells was analayzed and compared in response to phorbol myristate acetate (PMA) and opsonized zymosan (OZ) stimulants. It was shown that, like human blood neutrophils, both neutrophil-like cells expressed high levels of CD11b, but unlike human blood neutrophils these cells almost lack LCL-detectable intracellular oxidase activity. By studying the pattern of activation to OZ and PMA and priming with GM-CSF, we concluded that there is no difference between the percentage of differentiation and function of DMSO-induced HL 60 and PLB 985. However, the LCL capacity (area under the curve) of DMSO induced PLB 985 cells was higher than that of HL 60 cells in response to both PMA and OZ, which implies a higher capacity to generate reactive oxygen species in PLB 985 cells.

  7. Echinoderm reactive oxygen species (ROS) production measured by peroxidase, luminol-enhanced chemiluminescence (PLCL) as an immunotoxicological tool.

    PubMed

    Coteur, G; Danis, B; Dubois, P

    2005-01-01

    The importance of reactive oxygen species (ROS) production in invertebrate immunity prompted the use of this response in immunotoxicological studies in several taxa including marine organisms. In this chapter, we review the effects of environmental factors and contaminants such as heavy metals and polychlorinated biphenyls (PCBs) on the production of ROS by the main immune effector cells of echinoderms, the so-called amoebocytes. ROS production was measured by the peroxidase, luminol-enhanced chemiluminescence (PLCL) method. This method was found to predominantly reflect the production of superoxide anions and peroxides, among which hydrogen peroxide and peroxynitrite are the main species detected. Exogenous factors such as water temperature and salinity can influence this immune response in echinoderms. However, gender, handling stress and parasitism by a castrating ciliate apparently did not affect it. The impact of metals on ROS production differed greatly according to the duration and routes of exposure; in vitro and short-term in vivo exposures to metals caused an inhibition of this immune response, while the opposite effect was observed in a long-term in vivo exposure study. On the other hand, PCBs systematically had a stimulatory effect on ROS production independent of the echinoderm species or exposure routes. From the study of complex field contaminations, it appeared that contaminants released in the environment, such as metals, modulate starfish amoebocyte ROS production. This impact potentially represents a threat to the sustainability of natural populations of echinoderms and thereby to the stability of benthic ecosystems.

  8. Interaction of nitric oxide synthase inhibitors and their D-enantiomers with rat neutrophil luminol dependent chemiluminescence response.

    PubMed Central

    Dikshit, M.; Chari, S. S.; Seth, P.; Kumari, R.

    1996-01-01

    1. Formyl-methionyl-leucyl-phenylalanine (FMLP) or arachidonic acid (AA) induced luminol dependent chemiluminescence (LCL) response of rat polymorphonuclear leukocytes (PMNLs) was found to be inhibited by nitric oxide synthease inhibitors and their D-enantiomers. 2. Rat PMNLs LCL response was inhibited by NG-nitro-L-arginine methyl ester (L-NAME), D-NAME, NG-monomethyl-L-arginine (L-NMMA) or D-NMMA, in a concentration- and time-dependent manner. 3. It was observed that both L- and D-enantiomers of the arginine analogues (1000 microM) did not inhibit AA induced lucigenin-dependent chemiluminescence (LUCDCL) response and cytochrome c reduction, used for estimating the NADPH-oxidase activity in the cells and in the cell free system, respectively. 4. None of the L- and D-enantiomers had any effect on either rat basal PMNLs or AA-induced oxygen consumption. 5. In addition, neither the L nor D-enantiomers of NAME altered either AA-induced release or the activity of myeloperoxidase from rat PMNLs azurophilic granules. 6. The results obtained indicate that the attenuation of the LCL response by L- and D-enantiomers of arginine analogues, is a non-specific effect as there was no inhibition of NADPH-oxidase and MPO activity, MPO release or oxygen consumption. Therefore, the data obtained indicate that these agents should be used with caution to analyse the role of nitric oxide in rat PMNLs LCL response. PMID:8894181

  9. The chemiluminescence determination of 2-chloroethyl ethyl sulfide using luminol-AgNO3-silver nanoparticles system

    NASA Astrophysics Data System (ADS)

    Maddah, Bozorgmehr; Shamsi, Javad; Barsang, Mehran Jam; Rahimi-Nasrabadi, Mehdi

    2015-05-01

    A highly sensitive chemiluminescence (CL) method for the determination of 2-chloroethyl ethyl sulfide (2-CEES) was presented. It was found that 2-chloroethyl ethyl sulfide (2-CEES) could inhibit the CL of the luminol-AgNO3 system in the presence of silver nanoparticles in alkaline solution, which made it applicable for determination of 2-CEES. The presented method is simple, convenient, rapid and sensitive. Under the optimized conditions, the calibration curve was linear in the range of 0.0001-1 ng mL-1, with the correlation coefficient of 0.992; while the limit of detection (LOD), based on signal-to-noise ratio (S/N) of 3, was 6 × 10-6 ng mL-1. Also, the relative standard deviation (RSD, n = 5) for determination of 2-CEES (0.50 ng mL-1) was 3.1%. The method was successfully applied for the determination of 2-CEES in environmental aqueous samples.

  10. Determination of subnanomolar concentrations of vanadium in environmental water samples using flow injection with luminol chemiluminescence detection.

    PubMed

    Attiq-ur-Rehman; Yaqoob, Mohammad; Waseem, Amir; Nabi, Abdul

    2011-01-01

    A flow injection chemiluminescence method is described for the determination of subnanomolar concentrations of vanadium in environmental water samples. The procedure is based on the oxidation of luminol in the presence of dissolved oxygen catalyzed by vanadium(IV). Vanadium(V) reduction and preconcentration of vanadium(IV) was carried out using in-line silver reductor and 8-hydroxyquinoline chelating columns at pH 3.15, respectively. The calibration graph for vanadium(IV) was linear in the concentration range of 0.025-10 µg/L with relative standard deviation in the range of 0.4-5.58%. The detection limit (3s blank) was 3.8 × 10(-3) µg/L without preconcentration; when the vanadium(IV) was preconcentrated with an 8-HQ column for 1 min (2.0 mL of sample loaded), the detection limit of 5.1 × 10(-4) µg/L was achieved. One analytical cycle can be completed in 2.0 min. The analysis of certified reference materials (CASS-4, NASS-5 and SLRS-4) by the proposed method showed good agreement with the certified values. The method was successfully applied to the determination of total dissolved vanadium in environmental water samples.

  11. Sensitive determination of gentiopicroside in medicine and bio-fluids using luminol-myoglobin chemiluminescence combined with flow injection technique.

    PubMed

    He, Xili; Xie, Xiaofeng; Shao, Xiaodong; Song, Zhenghua

    2010-01-01

    A novel chemiluminescence method for the determination of gentiopicroside is presented, which was based on the inhibitory effect of gentiopicroside on the chemiluminescence reaction between luminol and myoglobin in a flow-injection system. The decrement of chemiluminescence intensity was linear with the logarithm of gentiopicroside concentration over the range from 10.0 pg mL(-1) to 500.0 ng mL(-1) (r(2) = 0.9992), with a detection limit of 3.0 pg mL(-1) (3σ). At a flow rate of 2.0 mL min(-1), a complete analytical process could be performed within 0.5 min, including sampling and washing, with a relative standard deviation of less than 3.0% (n = 5). The proposed procedure was applied successfully in the determination of gentiopicroside in pharmaceutical preparations, human urine and serum without any pretreatment procedure. The possible mechanism of the reaction was also discussed.

  12. Mechanisms of strontium and uranium removal from high-level radioactive waste simulant solutions by the sorbent monosodium titanate.

    PubMed

    Duff, M C; Hunter, D B; Hobbs, D T; Fink, S D; Dai, Z; Bradley, J P

    2004-10-01

    High-level waste (HLW) is a waste associated with the dissolution of spent nuclear fuel for the recovery of weapons-grade material. It is the priority problem for the U.S. Department of Energy's Environmental Management Program. Current HLW treatment processes at the Savannah River Site (Aiken, SC) include the use of monosodium titanate (MST, with a similar stoichiometry to NaTi2O5 x xH2O) to concentrate strontium (Sr) and actinides. The high affinity of MST for Sr and actinides in HLW solutions rich in Na+ is poorly understood. Mechanistic information about the nature of radionuclide uptake will provide insight about MST treatment reliability. Our study characterized the morphology of MST and the chemistry of sorbed Sr2+ and uranium [U(VI)] as uranyl ion, UO2(2+), on MST, which were added (individually) from stock solutions of Sr and 238U(VI) with spectroscopic and transmission electron microscopic techniques. The local structure of sorbed U varied with loading, but the local structure of Sr did not vary with loading. Sorbed Sr exhibited specific adsorption as partially hydrated species whereas sorbed U exhibited specific adsorption as monomeric and dimeric U(VI)-carbonate complexes. Sorption proved site specific. These differences in site specificity and sorption mechanism may account forthe difficulties associated with predicting Sr and U loading and removal kinetics using MST.

  13. Long term effects of monosodium glutamate on spermatogenesis following neonatal exposure in albino mice--a histological study.

    PubMed

    Das, R S; Ghosh, S K

    2010-09-01

    Monosodium glutamate (MSG), popularly known as Azinomoto has been in use since long as a flavour enhancing substance. Its widespread use has also earned it a bad name as hazardous for human health. It has been incriminated to cause wide range of effects comprising retinal degeneration, metabolic disorders, endocrinal disorders including reduced fertility rate in both male and female experimental mice and rats following neonatal exposure. However there are many contradicting views too regarding the above effects which have prompted us to undertake the present study. In our study seven newborns of Swiss Albino mice were injected subcutaneously with MSG (2 mg/gm ofbody wt. in a dilution 40 mg of per ml. of distilled water) on completion of 2nd, 4th, 6th, 8th and 10th day of life. Similar number of controls were injected with same volume of distilled water. Testes were obtained through dissection on completion of 75 days of life. 5 micron thick sections were cut, stained by H.E. and Heidenhain's Iron Haematoxylin and studied under light microscope. It was observed from the quantitative analysis of the seminiferous tubules that there was increase in the number of the pachytene stage of primary spermatocyte in the experimental group as compared to that of the control animals of corresponding age.

  14. The prevalence of monosodium urate and calcium pyrophosphate crystals in synovial fluid from wrist and finger joints.

    PubMed

    Galozzi, Paola; Oliviero, Francesca; Frallonardo, Paola; Favero, Marta; Hoxha, Ariela; Scanu, Anna; Lorenzin, Mariagrazia; Ortolan, Augusta; Punzi, Leonardo; Ramonda, Roberta

    2016-03-01

    The aim of this study was to assess the frequency of monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals in synovial fluids (SFs) aspirated from wrist and finger joints of patients with previously diagnosed joint diseases. We reviewed the results of SF analysis of 1593 samples and identified 126 patients with effusions in the small joints of the hands and wrists. We reported from patients' medical files data about sex, age, diagnosis, disease duration and the microscopic SF results. The prevalence of CPP crystals in SF was 85.71% in CPP-crystals arthritis (CPP-CA), 19.35% in rheumatoid arthritis (RA), 13.89% in osteoarthritis (OA) and 0% in psoriatic arthritis (PsA), spondyloarthritis (SpA), gout and miscellanea. The prevalence of MSU crystals in SF was 83.3% in gout, 10% in PsA, 2.8% in OA and 0% in RA, SpA, miscellanea and CPP-CA. Consistent with previously reported data concerning the big joints, microcrystals can be frequently found also in the small joints of patients with previous diagnosis. The finding underlines the importance of analyzing SF from the hand and wrist joints in the attempt to identify comorbidities associated with the presence of crystals and to develop targeted treatment strategies.

  15. Effect of iNOS inhibitor S-methylisothiourea in monosodium iodoacetate-induced osteoathritic pain: implication for osteoarthritis therapy.

    PubMed

    More, Amar S; Kumari, Rashmi R; Gupta, Gaurav; Lingaraju, Madhu C; Balaganur, Venkanna; Pathak, Nitya N; Kumar, Dhirendra; Kumar, Dinesh; Sharma, Anil K; Tandan, Surendra K

    2013-02-01

    Much information is available on the role of nitric oxide (NO) in osteoarthritis (OA). However, its role has not been studied in the monosodium iodoacetate (MIA)-induced model of osteoarthritic pain. The present study was undertaken in rats to investigate the effect of iNOS inhibitor S-methylisothiourea (SMT) in MIA-induced osteoathritic pain and disease progression in rats. Osteoarthritis was produced by single intra-articular injection of the MIA in the right knee joint on day 0. Treatment groups were orally gavazed with different doses of SMT (10, 30 and 100mg/kg) and etoricoxib (10mg/kg) daily for 21 days. On days 0, 3, 7, 14 and 21, pain was measured and histopathology of right knee joint was done on day 21. SMT produced analgesia in a dose-dependent manner as shown by mechanical, heat hyperalgesia, knee vocalization, knee squeeze test, and spontaneous motor activity test. SMT reduced NO production in synovial fluid. Histopathological findings indicated that SMT reduced disease progression as evident from complete cartilage formation in rats treated with SMT at 30 mg/kg. In conclusion, the results indicate that SMT attenuates the MIA-induced pain and histopathological changes in the knee joint. The antinociceptive and antiarthritic effects of SMT were mediated by inhibiting cartilage damage and suppression of NO in synovial fluid. It is suggested that SMT has potential as a therapeutic modality in the treatment of osteoarthritis. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Schisandrae Fructus ethanol extract ameliorates inflammatory responses and articular cartilage damage in monosodium iodoacetate-induced osteoarthritis in rats

    PubMed Central

    Jeong, Jin-Woo; Kim, Jongsik; Choi, Eun Ok; Kwon, Da Hye; Kong, Gyu Min; Choi, Il-Whan; Kim, Bum Hoi; Kim, Gi-Young; Lee, Ki Won; Kim, Ki Young; Kim, Sung Goo; Choi, Young Whan; Hong, Su Hyun; Park, Cheol; Choi, Yung Hyun

    2017-01-01

    Schisandrae Fructus, the fruit of Schisandra chinensis (Turcz.) Baill., is widely used in traditional medicine for the treatment of a number of chronic diseases. Although, Schisandrae Fructus was recently reported to attenuate the interleukin (IL)-1β-induced inflammatory response in chondrocytes in vitro, its protective and therapeutic potential against osteoarthritis (OA) in an animal model remains unclear. Therefore, we investigated the effects of the ethanol extract of Schisandrae Fructus (SF) on inflammatory responses and cartilage degradation in a monosodium iodoacetate (MIA)-induced OA rat model. Our results demonstrated that administration with SF had a tendency to attenuate MIA-induced damage of articular cartilage as determined by a histological grade of OA. SF significantly suppressed the production of pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α in MIA-induced OA rats. SF also effectively inhibited expression of inducible nitric oxide (NO) synthase and cyclooxygenase-2, thereby inhibiting the release of NO and prostaglandin E2. In addition, the elevated levels of matrix metalloproteinases-13 and two biomarkers for diagnosis and progression of OA, such as cartilage oligomeric matrix protein and C-telopeptide of type II collagen, were markedly ameliorated by SF administration. These findings indicate that SF could be a potential candidate for the treatment of OA. PMID:28507472

  17. Arsenic accumulation in bark beetles and forest birds occupying mountain pine beetle infested stands treated with monosodium methanearsonate.

    PubMed

    Morrissey, Christy A; Albert, Courtney A; Dods, Patti L; Cullen, William R; Lai, Vivian W M; Elliott, John E

    2007-02-15

    The arsenic-based pesticide, monosodium methanearsonate (MSMA), is presently being evaluated for re-registration in Canada and the United States and has been widely used in British Columbia to help suppress Mountain Pine Beetle (MPB) outbreaks. We assessed the availability and exposure of MSMA to woodpeckers and other forest birds that may prey directly on contaminated bark beetles. Total arsenic residues in MPB from MSMA treated trees ranged from 1.3-700.2 microg g(-1) dw (geometric mean 42.0 microg g(-1)) with the metabolite monomethyl arsonic acid (MMAA) contributing 90-97% to the total arsenic extracted. Live adult and larval beetles were collected from treated trees and reached concentrations up to 327 microg g(-1) dw. MPBs from reference trees had significantly lower arsenic concentrations averaging 0.19 microg g(-1) dw. Woodpeckers foraged more heavily on MSMAtreesthat contained beetles with lower arsenic residues, suggesting those trees had reduced MSMAtranslocation and possibly greater live beetle broods. Blood samples from five species of woodpeckers and other forest passerines breeding within 1 km of MSMA stands contained elevated levels of total arsenic but with large individual variability (geometric mean = 0.18 microg g(-1) dw, range 0.02-2.20 microg g(-1). The results indicate that there is significant accumulation and transfer of organic arsenic within the food chain at levels that may present a toxicity risk to avian wildlife.

  18. Augmented chondroprotective effect of coadministration of celecoxib and rebamipide in the monosodium iodoacetate rat model of osteoarthritis.

    PubMed

    Moon, Su-Jin; Park, Jin-Sil; Jeong, Jeong-Hee; Yang, Eun-Ji; Park, Mi-Kyung; Kim, Eun-Kyung; Park, Sung-Hwan; Kim, Ho-Youn; Cho, Mi-La; Min, Jun-Ki

    2013-01-01

    Osteoarthritis (OA) is a degenerative joint disease characterized by the progressive loss of articular cartilage and chronic pain. Although cyclooxygenase-2 (COX-2) inhibitors such as celecoxib are recommended to patients at high risk of gastrointestinal (GI) adverse events, COX-2 inhibitors do not completely prevent GI adverse events. Rebamipide, a gastroprotective agent, has anti-inflammatory properties and acts as an oxygen radical scavenger. The aim of this study was to investigate the in vivo effects of coadministration of rebamipide and celecoxib in an OA rat model. OA was induced by intra-articular injection of monosodium iodoacetate. Oral administration of rebamipide was initiated on the day of OA induction. In this study, rebamipide showed antinociceptive properties and attenuated cartilage degeneration. Rebamipide reduced the expression of matrix metalloproteinase 13, interleukin-1β, inducible nitric oxide synthase, and nitrotyrosine in OA cartilage. OA rats treated with celecoxib in combination with rebamipide demonstrated a higher pain threshold than those treated with monotherapy. Histological examination also showed that the joints from OA animals treated with combination therapy demonstrated less cartilage damage than those of animals treated with monotherapy. We showed that the potential benefit of combination therapy with celecoxib and rebamipide on pain and cartilage degeneration in OA.

  19. Uptake, distribution and elimination of monosodium methanearsonate following long term oral administration of the herbicide to sheep and goats.

    PubMed

    Shariatpanahi, M; Anderson, A C

    1984-08-01

    The rate and extent of accumulation and washout of arsenic, during daily oral administration of the herbicide monosodium methanearsonate (MSMA) were evaluated in Iranian dairy sheep and goats. Subjects received a dose of 10 mg of MSMA as arsenic per kg of body weight daily for 28 consecutive days. The total arsenic concentration in blood and milk was measured during and after the period of MSMA administration while arsenic in urine and feces was measured for 10 days following administration of last dosage of MSMA. Arsenic was accumulated slowly during 28 days of MSMA administration and steady states were essentially complete in sheep after 20 days and in goats following 25 days of MSMA administration. Blood arsenic concentration decreased rapidly after termination of MSMA administration. In both test animals, the half-lives of washout were smaller than accumulation. The concentration of arsenic in the urine and feces of both species did not increase significantly over controls and animals were free of arsenic relatively shortly after administration stopped. These data indicate that arsenic from MSMA is mainly absorbed from gastrointestinal tract and is not significantly accumulated in the body. Arsenic is eliminated from body by way of urine and feces with urinary excretion being the most important route.

  20. Distribution and toxicity of monosodium methanearsonate following oral administration of the herbicide to dairy sheep and goats.

    PubMed

    Shariatpanahi, M; Anderson, A C

    1984-01-01

    Iranian fat-tailed sheep and dairy goats were administered the herbicide monosodium methanearsonate orally at a dose of 10 mg. MSMA (as arsenic) per kg. of body weight. The concentration time curves of MSMA in the blood of sheep and goats followed a first order composite exponential equation of the form: Cb(t) = Ae- alpha t + Be- beta t - C degrees be-kat. Absorption, distribution and elimination of MSMA, therefore, corresponds to an open two-compartment model. Arsenic from MSMA was readily absorbed from gastrointestinal tract and distributed in the body fluids and the various tissues. Approximately 90% of the arsenic was excreted in the urine within 120 hrs and small amounts were also recovered in feces. Arsenic accumulation in the tissues was low and urinary excretion was the most important exit route. Arsenic concentrations in milk were low when compared to the controls, which indicates that arsenic is not excreted in the milk to significant levels. The absorption, distribution and overall elimination rate constants for the two animal species studied were statistically different at the 0.95 level of confidence which indicates that there are apparently differences in MSMA metabolism by sheep and goats.

  1. Stability of monosodium glutamate in green table olives and pickled cucumbers as a function of packing conditions and storage time.

    PubMed

    de Castro, Antonio; Sánchez, Antonio Higinio; Beato, Víctor Manuel; Casado, Francisco Javier; Montaño, Alfredo

    2014-01-01

    The effects of different packing conditions and storage times on the stability of monosodium glutamate (MSG) added to two different fermented vegetables (Spanish-type green table olives and pickled cucumbers) were studied. Factors such as packaging material (glass bottle versus plastic pouch), heat treatment (pasteurisation versus non-pasteurisation), and the presence or not of a preservative compound (potassium sorbate) were considered. The MSG content of pickled cucumbers was stable for up to 1 year of storage in all packing conditions studied. The MSG content also remained stable in pasteurised green table olives. On the contrary, MSG was extensively degraded (>75% degradation) after 54 weeks of storage in unpasteurised green olives with a higher degradation rate in glass bottles compared with plastic pouches. In the presence of potassium sorbate, MSG was also considerably degraded in olives packed in plastic pouches (>50% degradation), but hardly degraded in glass bottles. The results indicate that MSG degradation in olives is due to the action of both lactic acid bacteria and yeasts, with the formation of γ-aminobutyric acid as the major end-product.

  2. Ibuprofen-loaded porous microspheres suppressed the progression of monosodium iodoacetate-induced osteoarthritis in a rat model.

    PubMed

    Park, Jang Won; Yun, Young-Pil; Park, Kyeongsoon; Lee, Jae Yong; Kim, Hak-Jun; Kim, Sung Eun; Song, Hae-Ryong

    2016-11-01

    The objectives of this study were (1) to fabricate ibuprofen-loaded porous microspheres (IBU/PMSs), (2) to evaluate the in vitro anti-inflammatory effects of the microspheres using LPS-induced inflammation in cultured synoviocytes, and (3) to evaluate the in vivo effect of the IBU/PMSs on the progression of monosodium iodoacetate (MIA)-induced osteoarthritis (OA) in a rat model. A dose-dependent in vitro anti-inflammatory effect on pro-inflammatory cytokine markers (matrix metallopeptidase-3 (MMP-3), matrix metallopeptidase-13 (MMP-13), cyclooxygenase-2 (COX-2), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5)), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α) was observed by confirming with real-time PCR analyses. In vivo, treatment with IBU/PMSs reduced MIA-stimulated mRNA expression of MMP-3, MMP-13, COX-2, ADAMTS-5, IL-6, and TNF-α in rat synoviocytes. In addition, we demonstrated that intra-articular IBU/PMSs suppressed the progression of MIA-induced OA in the rat model via anti-inflammatory mechanisms. In conclusion, IBU/PMSs are a promising therapeutic material to control the pain and progression of OA.

  3. Monosodium L-glutamate and dietary fat exert opposite effects on the proximal and distal intestinal health in growing pigs.

    PubMed

    Feng, Zemeng; Li, Tiejun; Wu, Chunli; Tao, Lihua; Blachier, Francois; Yin, Yulong

    2015-04-01

    The Chinese population has undergone rapid transition to a high-fat diet. Furthermore, monosodium L-glutamate (MSG) is widely used as a flavour enhancer in China. Previous studies have reported that high-fat diet modifies intestinal metabolism and physiology. However, little information is available on the effects of oral MSG on intestine, and no study focus on the interaction of dietary fat and MSG for intestinal health. The aim of the present study was to evaluate the effects of MSG and dietary fat on intestinal health in growing pigs, and to try to identify possible interactions between these 2 nutrients for such effects. A total of 32 growing pigs were used and fed with 4 isonitrogenous and isocaloric diets (basal diet, high-fat diet, basal diet with 3% MSG and high fat diet with 3% MSG). Parameters related to reactive oxygen species metabolism, epithelial morphology, pro-inflammation factors and tight junction protein expression and several species of intestinal microbe were measured. Overall, dietary fat and MSG had detrimental effects on several of the physiological and inflammatory parameters measured in the proximal intestine, while exerting beneficial effects on the distal intestine in growing pigs, with generally antagonistic effects. These results may be of particular relevance for nutritional concerns in patients with intestinal diseases.

  4. Quercetin ameliorates glucose and lipid metabolism and improves antioxidant status in postnatally monosodium glutamate-induced metabolic alterations.

    PubMed

    Seiva, Fábio R F; Chuffa, Luiz Gustavo A; Braga, Camila Pereira; Amorim, João Paulo A; Fernandes, Ana Angélica H

    2012-10-01

    We reported the effects of quercetin on metabolic and hormonal profile as well as serum antioxidant activities in a model of MSG (monosodium glutamate)-induced obesity. Rats were divided into 4 groups: MSG group, submitted to neonatal treatment with high doses of MSG, administrated subcutaneously during 10 days, from 2 day-old; control groups, which received the same volume of saline. After completing 30 day-old, these groups were subdivided into 4 groups: control and MSG groups treated and non-treated with quercetin at doses of 75 mg/kg body weight (i.p.) over 42 days. BW gain and food consumption were higher in MSG treated rats and quercetin significantly reduced BW by 25%. While MSG increased triacylglycerol, total cholesterol and fractions, and reduced HDL concentrations, administration of quercetin normalized HDL-cholesterol and reduced others lipids. Insulin, leptin, glucose and creatinine levels were raised in MSG-treated rats and reduced after quercetin treatment. Alanine transaminase, aspartate transaminase, lactate dehydrogenase and alkaline phosphatase activities were lower after MSG-quercetin combination compared to rats given only MSG. MSG-quercetin combination augmented total protein and urea levels as well as glutathione peroxidase and superoxide dismutase activities in contrast to MSG-treated animals. Quercetin normalized serum lipid and glucose profile and minimized the MSG-related toxic effects, which was associated to its antioxidant properties.

  5. High dosage of monosodium glutamate causes deficits of the motor coordination and the number of cerebellar Purkinje cells of rats.

    PubMed

    Prastiwi, D; Djunaidi, A; Partadiredja, G

    2015-11-01

    Monosodium glutamate (MSG) has been widely used throughout the world as a flavoring agent of food. However, MSG at certain dosages is also thought to cause damage to many organs, including cerebellum. This study aimed at investigating the effects of different doses of MSG on the motor coordination and the number of Purkinje cells of the cerebellum of Wistar rats. A total of 24 male rats aged 4 to 5 weeks were divided into four groups, namely, control (C), T2.5, T3, and T3.5 groups, which received intraperitoneal injection of 0.9% sodium chloride solution, 2.5 mg/g body weight (bw) of MSG, 3.0 mg/g bw of MSG, and 3.5 mg/g bw of MSG, respectively, for 10 consecutive days. The motor coordination of the rats was examined prior and subsequent to the treatment. The number of cerebellar Purkinje cells was estimated using physical fractionator method. It has been found that the administration of MSG at a dosage of 3.5 mg/g bw, but not at lower dosages, caused a significant decrease of motor coordination and the estimated total number of Purkinje cells of rats. There was also a significant correlation between motor coordination and the total number of Purkinje cells.

  6. Effects of Extract from Mangifera indica Leaf on Monosodium Urate Crystal-Induced Gouty Arthritis in Rats.

    PubMed

    Jiang, Yan; You, Xiao-Ying; Fu, Kong-Long; Yin, Wan-Le

    2012-01-01

    The leaves of Mangifera indica L. (Anacardiaceae) is used as a medicinal material in traditional herb medicine for a long time in India, China, and other Eastern Asian countries. Our present study investigated the therapeutic effects of the ethanol extract from Mangifera indica (EMI) in rat with monosodium urate (MSU) crystals-induced gouty arthritis. Effects of EMI (50, 100, and 200 mg/kg, p.o.) administrated for 9 days on the ankle swelling, synovial tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β) levels were assessed in MSU crystal rat. Data from our study showed that rat with gouty arthritis induced by MSU crystal demonstrated an elevation in ankle swelling, synovial TNF-α, IL-1β mRNA, and protein levels. Oral administration of 100 and 200 mg/kg EMI for 9 days reversed the abnormalities in ankle swelling, synovial TNF-α, IL-1β mRNA, and protein levels. The results indicated that the beneficial antigouty arthritis effect of EMI may be mediated, at least in part, by inhibiting TNF-α and IL-1β expression in the synovial tissues. Our study suggests that Mangifera indica and its extract may have a considerable potential for development as an anti-gouty arthritis agent for clinical application.

  7. Monosodium urate crystals induce extracellular DNA traps in neutrophils, eosinophils, and basophils but not in mononuclear cells.

    PubMed

    Schorn, Christine; Janko, Christina; Latzko, Melanie; Chaurio, Ricardo; Schett, Georg; Herrmann, Martin

    2012-01-01

    Neutrophil extracellular traps (NETs) are fibers of extracellular DNA released from neutrophils due to overwhelming phagocytic stimuli. The function of NETs is to trap and kill microbes to avoid spreading of potential pathogens. NETs are formed after encounter with various gram-positive and -negative bacteria but also in response to mediators causing sterile inflammation like interleukin-8 (IL-8), tumor necrosis factor (TNF), and phorbol myristate acetate (PMA). Here we show the formation of NETs (NETting) in response to monosodium urate (MSU) crystals as further model for sterile inflammation. We identified monocytes, neutrophils, and eosinophils as MSU phagocytosing cells. Basophils did not take up the crystals, instead they upregulated their activation marker CD203c after contact with MSU. Nevertheless, MSU crystals induced extracellular trap formation also in basophils, like in eosinophils and neutrophils, which phagocytose the crystals. In contrast, monocytes do not form NETs despite uptake of the MSU crystals. In contrast to the canonical stimuli like bacteria and PMA, MSU-induced NETosis was not abrogated by plasma. Our data show that MSU crystals induce extracellular DNA trap formation in all three granulocytes lineages (NETs, EETs, and BETs) but not in monocytes, and DNA externalization does not necessitate the uptake of the crystals.

  8. Osteogenic Differentiation of Human and Ovine Bone Marrow Stromal Cells in response to β-Glycerophosphate and Monosodium Phosphate.

    PubMed

    Bottagisio, Marta; Lovati, Arianna B; Lopa, Silvia; Moretti, Matteo

    2015-08-01

    Bone defects are severe burdens in clinics, and thus cell therapy offers an alternative strategy exploiting the features of bone marrow stromal cells (BMSCs). Sheep are a suitable orthopedic preclinical model for similarities with humans. This study compares the influence of two phosphate sources combined with bone morphogenetic protein-2 (BMP-2) on the osteogenic potential of human and ovine BMSCs. β-Glycerophosphate (β-GlyP) and monosodium phosphate (NaH2PO4) were used as organic and inorganic phosphate sources. Osteogenic differentiation of the BMSCs was assessed by calcified matrix, alkaline phosphatase (ALP) activity, and gene expression analysis. A higher calcified matrix deposition was detected in BMSCs cultured with NaH2PO4. Although no significant differences were detected among media for human BMSCs, β-GlyP with or without BMP-2 determined a positive trend in ALP levels compared to NaH2PO4. In contrast, NaH2PO4 had a positive effect on ALP levels in ovine BMSCs. β-GlyP better supported the expression of COL1A1 in human BMSCs, whereas all media enhanced RUNX2 and SPARC expression. Ovine BMSCs responded poorly to any media for RUNX2, COL1A1, and SPARC expression. NaH2PO4 improved calcified matrix deposition without upregulating the transcriptional expression of osteogenic markers. A further optimization of differentiation protocols needs to be performed to translate the procedures from preclinical to clinical models.

  9. The effects of monosodium urate monohydrate crystals on chondrocyte viability and function: implications for development of cartilage damage in gout.

    PubMed

    Chhana, Ashika; Callon, Karen E; Pool, Bregina; Naot, Dorit; Gamble, Gregory D; Dray, Michael; Pitto, Rocco; Bentley, Jarome; McQueen, Fiona M; Cornish, Jillian; Dalbeth, Nicola

    2013-12-01

    Cartilage damage is frequently observed in advanced destructive gout. The aim of our study was to investigate the effects of monosodium urate monohydrate (MSU) crystals on chondrocyte viability and function. The alamarBlue assay and flow cytometry were used to assess the viability of primary human chondrocytes and cartilage explants following culture with MSU crystals. The number of dead chondrocytes in cartilage explants cultured with MSU crystals was quantified. Real-time PCR was used to determine changes in the relative mRNA expression levels of chondrocytic genes. The histological appearance of cartilage in joints affected by gout was also examined. MSU crystals rapidly reduced primary human chondrocyte and cartilage explant viability in a dose-dependent manner (p < 0.01 for both). Cartilage explants cultured with MSU crystals had a greater percentage of dead chondrocytes at the articular surface compared to untreated cartilage (p = 0.004). Relative mRNA expression of type II collagen and the cartilage matrix proteins aggrecan and versican was decreased in chondrocytes following culture with MSU crystals (p < 0.05 for all). However, expression of the degradative enzymes ADAMTS4 and ADAMTS5 was increased (p < 0.05 for both). In joints affected by gout, normal cartilage architecture was lost, with empty chondrocyte lacunae observed. MSU crystals have profound inhibitory effects on chondrocyte viability and function. Interactions between MSU crystals and chondrocytes may contribute to cartilage damage in gout through reduction of chondrocyte viability and promotion of a catabolic state.

  10. Progressive Depletion of Rough Endoplasmic Reticulum in Epithelial Cells of the Small Intestine in Monosodium Glutamate Mice Model of Obesity.

    PubMed

    Nakadate, Kazuhiko; Motojima, Kento; Hirakawa, Tomoya; Tanaka-Nakadate, Sawako

    2016-01-01

    Chronic obesity is a known risk factor for metabolic syndrome. However, little is known about pathological changes in the small intestine associated with chronic obesity. This study investigated cellular and subcellular level changes in the small intestine of obese mice. In this study, a mouse model of obesity was established by early postnatal administration of monosodium glutamate. Changes in body weight were monitored, and pathological changes in the small intestine were evaluated using hematoxylin-eosin and Nissl staining and light and electron microscopy. Consequently, obese mice were significantly heavier compared with controls from 9 weeks of age. Villi in the small intestine of obese mice were elongated and thinned. There was reduced hematoxylin staining in the epithelium of the small intestine of obese mice. Electron microscopy revealed a significant decrease in and shortening of rough endoplasmic reticulum in epithelial cells of the small intestine of obese mice compared with normal mice. The decrease in rough endoplasmic reticulum in the small intestine epithelial cells of obese mice indicates that obesity starting in childhood influences various functions of the small intestine, such as protein synthesis, and could impair both the defense mechanism against invasion of pathogenic microbes and nutritional absorption.

  11. Protective Effects of Catechin against Monosodium Urate-Induced Inflammation through the Modulation of NLRP3 Inflammasome Activation.

    PubMed

    Jhang, Jhih-Jia; Lu, Chi-Cheng; Ho, Cheng-Ying; Cheng, Yu-Ting; Yen, Gow-Chin

    2015-08-26

    Gouty inflammation results from the stimulation of monosodium urate (MSU). Interleukin-1β (IL-1β) secretion is the primary clinical manifestation of MSU attack, and MSU activates IL-1β through a nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome. This study investigated the protective effect and underlying mechanism of naturally occurring phenolic compounds on MSU-induced inflammation in vivo and in vitro. A screening of phenolic compounds revealed that gallic acid and catechin exhibited the most potent free radical scavenging activities. Subcutaneous injection of gallic acid or catechin significantly reduced MSU-induced IL-1β and IL-6 secretion in C57BL/6 mice. However, only catechin inhibited MSU-induced IL-1β secretion and NLRP3 inflammasome activation in MSU-challenged THP-1 cells. MSU-triggered mitochondrial reactive oxygen species (MtROS) production and intracellular calcium levels were significantly decreased by treatment with catechin in THP-1 cells. Catechin treatment also up-regulated Bcl-2 levels and restored MSU-induced mitochondrial transmembrane potential impairment. These results indicate that the protective effects of catechin on MSU-induced IL-1β secretion are associated with modulation of mitochondrial damage. It also suggests that catechin has the potential to protect gout attack by modulation of NLRP3 inflammasome activation.

  12. Progressive Depletion of Rough Endoplasmic Reticulum in Epithelial Cells of the Small Intestine in Monosodium Glutamate Mice Model of Obesity

    PubMed Central

    Nakadate, Kazuhiko; Motojima, Kento; Hirakawa, Tomoya; Tanaka-Nakadate, Sawako

    2016-01-01

    Chronic obesity is a known risk factor for metabolic syndrome. However, little is known about pathological changes in the small intestine associated with chronic obesity. This study investigated cellular and subcellular level changes in the small intestine of obese mice. In this study, a mouse model of obesity was established by early postnatal administration of monosodium glutamate. Changes in body weight were monitored, and pathological changes in the small intestine were evaluated using hematoxylin-eosin and Nissl staining and light and electron microscopy. Consequently, obese mice were significantly heavier compared with controls from 9 weeks of age. Villi in the small intestine of obese mice were elongated and thinned. There was reduced hematoxylin staining in the epithelium of the small intestine of obese mice. Electron microscopy revealed a significant decrease in and shortening of rough endoplasmic reticulum in epithelial cells of the small intestine of obese mice compared with normal mice. The decrease in rough endoplasmic reticulum in the small intestine epithelial cells of obese mice indicates that obesity starting in childhood influences various functions of the small intestine, such as protein synthesis, and could impair both the defense mechanism against invasion of pathogenic microbes and nutritional absorption. PMID:27437400

  13. New therapeutic strategy for amino acid medicine: prophylactic and healing promoting effect of monosodium glutamate against NSAID-induced enteropathy.

    PubMed

    Amagase, Kikuko; Ochi, Akimu; Kojo, Azusa; Mizunoe, Ami; Taue, Masaya; Kinoshita, Naoya; Nakamura, Eiji; Takeuchi, Koji

    2012-01-01

    We reviewed the effect of monosodium glutamate (MSG) on the development and healing of nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal lesions in rats. Loxoprofen (60 mg/kg, p.o.) induced lesions in the small intestine within 24 h, accompanied by a decrease of Muc2 expression and an increase in enterobacterial invasion and inducible nitric oxide synthase (iNOS) expression. These lesions were prevented when MSG was given as a mixture of powdered food for 5 days before the loxoprofen treatment. This effect of MSG was accompanied by an increase in Muc2 expression / mucus secretion as well as the suppression of bacterial invasion and iNOS expression. These intestinal lesions healed spontaneously within 6 days, but the process was impaired by the repeated administration of low-dose loxoprofen (30 mg/kg) for 5 days after the ulceration, with the decrease of vascular endothelial derived growth factor (VEGF) expression and angiogenesis. The healing-impairing effect of loxoprofen was prevented by feeding 5% MSG for 5 days after the ulceration. These results suggest that MSG not only prevents loxoprofen-induced small intestinal damage but also promotes a healing of these lesions; the former is functionally associated with the increase in Muc2 expression / mucus secretion and the suppression of bacterial invasion and iNOS expression, while the latter is associated with the stimulation of VEGF expression/angiogenesis.

  14. Effects of RuPeng15 Powder (RPP15) on Monosodium Urate Crystal-Induced Gouty Arthritis in Rats

    PubMed Central

    Kou, Y.-Y.; Li, Y.-F.; Xu, M.; Li, W.-Y.; Yang, M.; Li, R.-L.

    2015-01-01

    RuPeng15 Powder (RPP15) is a herbal multicompound remedy that originates from traditional Tibetan medicine and possesses antigout, anti-inflammatory, and antihyperuricemic properties based on the traditional conceptions. The present study was undertaken to evaluate the therapeutic effect of PRP15 in rat gouty arthritis induced by monosodium urate (MSU) crystals. In the present study, we found that treatment with RPP15 (0.4, 0.8, and 1.2 g/kg) in rats with gouty arthritis induced by MSU crystals significantly attenuated the knee swelling. Histomorphometric and immunohistochemistry analyses revealed that MSU-induced inflammatory cell infiltration and the elevated expressions of nuclear transcription factor-κB p65 (NF-κB p65) in synovial tissues were significantly inhibited, and enzyme-linked immunosorbent assay (ELISA) result showed that MSU-induced high levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-8 (IL-8) in synovial fluid were reduced by treatment with RPP15 (0.4, 0.8, and 1.2 g/kg). We conclude that RPP15 may be a promising candidate for the development of a new treatment for gout and its activity of antigout may be partially related to inhibiting TNF-α, IL-1β, IL-8, and NF-κB p65 expression in the synovial tissues. PMID:26221174

  15. The neonatal neurotoxicity of monosodium L-glutamate on the sexually dimorphic nucleus of the preoptic area in rats.

    PubMed

    Hsieh, Y L; Hsu, C; Lue, S I; Hsu, H K; Peng, M T

    1997-01-01

    The neurotoxic effect of monosodium L-glutamate (MSG) on the morphologies in the darkly stained sexually dimorphic nucleus of the preoptic area (SDN-POA) and the lighter-staining surrounding area (non-SDN-POA) within the medial preoptic nucleus (MPN) was evaluated. Male and female Long-Evans rats were used. MSG (4 mg/g of body weight) was administered subcutaneously to pups on days 1 and 3 postnatally. Normal saline was used as the vehicle. At the age of 6 months, the rats were sacrificed and the brain tissues were fixed for histological examination. The morphological changes, i.e., total volume, density, total neuron number, neuronal nuclear volume (NNV) and ratio of pyknosis, of the SDN-POA and non-SDN-POA within the MPN, were estimated using the AMS VIDS III semiautomatic image-analytic system. The results indicate that neonatal MSG treatment caused significant neuronal loss and decreases in total volume of the SDN-POA and non-SDN-POA of male and female rats. However, only the SDN-POA of MSG-treated male rats showed a significant increase of pyknosis and decrease of neuronal density. A significant enlargement of NNV in the SDN-POA and non-SDN-POA was observed in the MSG-treated male rats. These results indicate that the MPN shows sex-specific and area-specific changes after neonatal neurotoxicity due to MSG.

  16. Anti-Osteoarthritic Effects of the Litsea japonica Fruit in a Rat Model of Osteoarthritis Induced by Monosodium Iodoacetate

    PubMed Central

    Park, Dae Won; Kwon, Jung Eun; Jung, Moon Won; Meng, Xue; Jo, Se Min; Song, Hae Seong; Cho, Young Mi; Song, Sang Mok; Ham, Young-Min; Jung, Yong-Hwan; Kim, Chang Sook; Yoon, Weon-Jong; Kang, Se Chan

    2015-01-01

    Osteoarthritis (OA) is a degenerative chronic disease that affects various tissues surrounding the joints, such as the subchondral bone and articular cartilage. The onset of OA is associated with uncontrolled catabolic and anabolic remodeling processes of the joints, including the cartilage and subchondral bone, to adapt to local biological and biochemical signals. In this study, we determined whether 70% ethanolic (EtOH) extract of Litsea japonica fruit (LJFE) had beneficial effects on the articular cartilage, including structural changes in the tibial subchondral bone, matrix degradation, and inflammatory responses, in OA by using a rat model of monosodium iodoacetate-induced OA. Our results showed that administration of LJFE increased the bone volume and cross-section thickness, but the mean number of objects per slice in this group was lower than that in the OA control (OAC) group. In addition, the LJFE decreased the expression of inflammatory cytokines. Compared to the OAC group, the group treated with high doses of LJFE (100 and 200 mg/kg) showed a more than 80% inhibition of the expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases. Our results suggest that LJFE can be used as a potential anti-osteoarthritic agent. PMID:26244981

  17. THE HYDROTHERMAL REACTIONS OF MONOSODIUM TITANATE, CRYSTALLINE SILICOTITANATE AND SLUDGE IN THE MODULAR SALT PROCESS: A LITERATURE SURVEY

    SciTech Connect

    Fondeur, F.; Pennebaker, F.; Fink, S.

    2010-11-11

    The use of crystalline silicotitanate (CST) is proposed for an at-tank process to treat High Level Waste at the Savannah River Site. The proposed configuration includes deployment of ion exchange columns suspended in the risers of existing tanks to process salt waste without building a new facility. The CST is available in an engineered form, designated as IE-911-CW, from UOP. Prior data indicates CST has a proclivity to agglomerate from deposits of silica rich compounds present in the alkaline waste solutions. This report documents the prior literature and provides guidance for the design and operations that include CST to mitigate that risk. The proposed operation will also add monosodium titanate (MST) to the supernate of the tank prior to the ion exchange operation to remove strontium and select alpha-emitting actinides. The cesium loaded CST is ground and then passed forward to the sludge washing tank as feed to the Defense Waste Processing Facility (DWPF). Similarly, the MST will be transferred to the sludge washing tank. Sludge processing includes the potential to leach aluminum from the solids at elevated temperature (e.g., 65 C) using concentrated (3M) sodium hydroxide solutions. Prior literature indicates that both CST and MST will agglomerate and form higher yield stress slurries with exposure to elevated temperatures. This report assessed that data and provides guidance on minimizing the impact of CST and MST on sludge transfer and aluminum leaching sludge.

  18. Determination of rutin by flow injection chemiluminescence method using the reaction of luminol and potassium hexacyanoferrate(III) with the aid of response surface methodology.

    PubMed

    Yang, Dan; Li, Haiyun; Li, Ziyuan; Hao, Zaibin; Li, Jianping

    2010-01-01

    A novel flow injection chemiluminescence (CL) method for the determination of rutin was reported. The proposed method was based on the enhanced effect of rutin on the chemiluminescence intensity of luminol and potassium hexacyanoferrate(III) reaction in NaOH medium. The variables of reaction system, such as luminol concentration, potassium hexacyanoferrate(III) concentration and NaOH concentration, were optimized with the aid of response surface methodology. For the responses prediction, a second-order polynomial model (SOPM) was applied. The optimal conditions for determination of rutin estimated by the model equation were as follows: NaOH concentration of 0.13 mol/L luminol concentration of 0.94 × 10(-6)  mol/L, and K(3) Fe(CN)(6) concentration of 1.09 × 10(-4)  mol/L. The theoretical increased ratio of CL intensity (IRI) predicted and actual IRI for 0.05 mg/L rutin under the above conditions were 99.40 and 99.74%, respectively. The SOPM model proved to be powerful for navigating the design space. Under the above optimum conditions, the increased IRI was linearly related to the concentration of rutin in the range from 0.008 to 0.100 mg/L with the regression equation IRI = 1948.20c + 5.24 (r = 0.9994) and in the range from 0.100 to 1.000 mg/L with the regression equation IRI = 1362.50 c + 61.94 (r = 0.9996). The detection limit (3σ) was of 1.95 × 10(-3)  mg/L. The sampling frequency of this method was 72/h. The method was used directly to determine rutin in tablets. Copyright © 2009 John Wiley & Sons, Ltd.

  19. In vitro study of the antioxidant properties of nimesulide and 4-OH nimesulide: effects on HRP- and luminol-dependent chemiluminescence produced by human chondrocytes.

    PubMed

    Zheng, S X; Mouithys-Mickalad, A; Deby-Dupont, G P; Deby, C M; Maroulis, A P; Labasse, A H; Lamy, M L; Crielaard, J M; Reginster, J Y; Henrotin, Y E

    2000-11-01

    Reactive oxygen species (ROS) are now recognized to play an important role in the pathogenesis of rheumatic diseases and constitute an interesting therapeutic target for drugs. This in vitro study was designed to evaluate the antioxidant properties of nimesulide (NIM), a nonsteroidal antiinflammatory drug of the sulfonanilide class, and its main metabolite 4-OH nimesulide (4-OHNIM). The scavenging effects of NIM and 4-OH NIM on hydroxyl radical ((.)OH) and superoxide anions (O(minusd)(2)) were investigated by electron spin resonance (ESR), using 5, 5-dimethylpyrroline-N-oxide (DMPO) as the spin trap agent. The quenching properties of these drugs on hypochlorite anion was studied by luminol enhanced chemiluminescence. Finally, the effects of NIM and 4-OHNIM on the reactive oxygen species production by human articular chondrocytes were recorded by HRP and luminol-enhanced chemiluminescence. By this method it has been demonstrated that NIM and 4-OHNIM, at concentrations ranging from 10 to 100 microM, are potent scavengers of(.)OH whereas only 4-OHNIM was capable to scavenge O(minusd)(2). Chemiluminescence generated by HOCl was also significantly and dose-dependently inhibited by both NIM and 4-OHNIM. Nevertheless, at each concentration tested, the inhibitory effect of 4-OHNIM was significantly more marked, even at the highest concentration (100 microM). Furthermore, when chondrocytes were pre-incubated for 48-96 h with NIM or 4-OHNIM, the luminol- and HRP-dependent CL produced by the cells was significantly inhibited in a dose-dependent manner. NIM and 4-OHNIM may protect cartilage against oxidative stress, not only by scavenging ROS but also by inhibiting their production by chondrocytes. Copyright 2000 OsteoArthritis Research Society International.

  20. Switch-on fluorescence scheme for antibiotics based on a magnetic composite probe with aptamer and hemin/G-quadruplex coimmobilized nano-Pt-luminol as signal tracer.

    PubMed

    Miao, Yang-Bao; Gan, Ning; Ren, Hong-Xia; Li, Tianhua; Cao, Yuting; Hu, Futao; Chen, Yinji

    2016-01-15

    A selective and facile fluorescence "switch-on" scheme is developed to detect antibiotics residues in food, using chloramphenicol (CAP) as model, based on a novel magnetic aptamer probe (aptamer-Pt-luminol nanocomposite labeled with hemin/G-quadruplex). Firstly, the composite probe is prepared through the immuno-reactions between the capture beads (anti-dsDNA antibody labeled on magnetic Dynabeads) and the nanotracer (nano-Pt-luminol labeled with double-strand aptamer, as ds-Apt, and hemin/G-quadruplex). When the composite probe is mixed with CAP, the aptamer preferentially reacted with CAP to decompose the double-strand aptamer to ssDNA, which cannot be recognized by the anti-dsDNA antibody on the capture probes. Thus, after magnetic separation, the nanotracer can be released into the supernatant. Because the hemin/G-quadruplex and PtNPs in nanotracer can catalyze luminol-H2O2 system to emit fluorescence. Thus a dual-amplified "switch-on" signal appeared, of which intensity is proportional to the concentration of CAP between 0.001 and 100ng mL(-1) with detection limit of 0.0005ng mL(-1) (S/N=3). Besides, our method has good selectivity and was employed for CAP detection in real milk samples. The results agree well with those from conventional gas chromatograph-mass spectrometer (GC-MS). The switch-on signal is produced by one-step substitution reaction between aptamer in nanotracer and target. When the analyte is changed, the probe can be refabricated only by changing the corresponding aptamer. Thus, all features above prove our strategy to be a facile, feasible and selective method in antibiotics screening for food safety. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. One-pot synthesis of GO/AgNPs/luminol composites with electrochemiluminescence activity for sensitive detection of DNA methyltransferase activity.

    PubMed

    Zhao, Hui-Fang; Liang, Ru-Ping; Wang, Jing-Wu; Qiu, Jian-Ding

    2015-01-15

    DNA methyltransferases catalyze the transfer of a methyl group from S-adenosylmethionine to the target adenine or cytosine, eventually inducing the DNA methylation in both prokaryotes and eukaryotes. Herein, we developed a novel electrochemiluminescence biosensor to quantify DNA adenine methylation (Dam) methyltransferase (MTase) employing signal amplification of GO/AgNPs/luminol composites to enhance the assay sensitivity. The method was developed by designing a capture probe DNA, which was immobilized on gold electrode surface, to hybridize with azide complementary DNA to form the azide-terminated dsDNA. Then, alkynyl functionalized GO/AgNPs/luminol composites as the signal probe were immobilized to azide-terminated dsDNA modified electrode via click chemistry, resulting in a high electrochemiluminescence (ECL) signal. Once the DNA hybrid was methylated (under catalysis of Dam MTase) and further cleaved by Dpn I endonuclease (a site-specific endonuclease recognizing the duplex symmetrical sequence of 5'-G-Am-T-C-3'), GO/AgNPs/luminol composites release from the electrode surface to the solution, leading to significant reduction of the ECL signal. The change of the ECL intensity is related to the methylation status and MTase activity, which forms the basis of MTase activity assay and site-specific methylation determination. This novel strategy can be further used as a universal method for other transferase determination by designing various transferase-specific DNA sequences. In addition, this method can be used for the screening of antimicrobial drugs and has a great potential to be further applied in early clinical diagnosis. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Employment of bromophenol red and bovine serum albumin as luminol signal co-enhancer in chemiluminescent detection of sequence-specific DNA.

    PubMed

    Yu, Xiaoqian; Sheng, Yingying; Zhao, Yanjun; Fan, Aiping

    2016-01-01

    Bromophenol red, known as chemical indicator, was found to act as a novel potent signal enhancer of the peroxidase-catalyzed luminol-H2O2 chemiluminescent (CL) reaction. It was found interestingly that bovine serum albumin (BSA) played a role in the enhanced chemiluminescent reaction (ECR). The addition of 2.5 mg mL(-1) BSA into bromophenol red-enhance CL system showed 36 times stronger CL signal than that without addition of BSA. Mechanism study showed that the luminophors in the ECR were still 3-aminophthalate ion in an excited state (3-APA*). In addition, singlet oxygen ((1)O2) and hydroxyl radical ((∙)OH) played a role in the ECR. The possible mechanism was discussed in the present study. The effect of pH, reaction time, and concentration of bromophenol red, BSA, luminol, and H2O2 on CL intensity of the peroxidase-catalyzed CL reaction was studied. The detection limit value (LOD) of HRP and streptavidin-modified HRP in the proposed ECR with bromophenol red and BSA was 0.20 ng mL(-1) and 0.05 ng mL(-1), respectively. This novel luminol-H2O2-HRP-bromophenol red-BSA CL system was applied to the CL detection of sequence-specific DNA based on a magnetic separation process. As low as 0.4 fmol of target DNA could be sensitively detected using the proposed CL system without any amplification process. The obtained results demonstrate very promising perspectives for using bromophenol red and BSA to improve the sensitivity of CL detection of sequence-specific DNA. In addition, this novel ECR system can also be generalized for CL immunoassay, CL western blotting, and so on. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Luminol testing in detecting modern human skeletal remains: a test on different types of bone tissue and a caveat for PMI interpretation.

    PubMed

    Caudullo, Giorgio; Caruso, Valentina; Cappella, Annalisa; Sguazza, Emanuela; Mazzarelli, Debora; Amadasi, Alberto; Cattaneo, Cristina

    2017-01-01

    When forensic pathologists and anthropologists have to deal with the evaluation of the post-mortem interval (PMI) in skeletal remains, luminol testing is frequently performed as a preliminary screening method. However, the repeatability of this test on the same bone, as well as comparative studies on different bones of the same individual, has never been performed. Therefore, with the aim of investigating the influence that different types of bones may exert on the response to the luminol test, the present study analysed three different skeletal elements (femoral diaphysis, vertebra and cranial vault), gathered from ten recent exhumed skeletons (all with a 20-year PMI). The analysis was performed twice on the same bone after 2 months: the analysis at time 0 concerned the whole bone, whereas the second concerned only a part of the same bone taken during the first test (which already had been broken). The overall results showed different responses, depending on the type of bone and on the integrity of the samples. Negative results at the first analysis (6.6% out of the total of samples) are consistent with what is reported in the literature, whilst at the second analysis, the increase of about 20% of false-negative results highlights that the luminol test ought to be performed with caution in case of broken bones or elements which are taphonomically altered. Results have thus proven that the exposition to environmental agents might result in haemoglobin (Hb) loss, as detected even after only 2 months. The study also focused on the crucial issue of the type of bone subjected to testing, remarking the suitability of the femoral diaphysis (100% of positive responses at the first analysis vs only 18% of false-negative results at the second test, corresponding to 5% of total false-negative results) as opposed to other bone elements that showed a low yield. In particular, the cranial vault gave poor results, with 40% of discrepancy between results from the two analyses

  4. Effect of thiol drugs on tert-butyl hydroperoxide induced luminol chemiluminescence in human erythrocytes, erythrocyte lysate, and erythrocyte membranes.

    PubMed

    Sajewicz, Waldemar

    2010-07-30

    The paper investigates the effect of thiol drugs (RSH) under oxidative stress condition using luminol-enhanced chemiluminescence technique. The examinations included N-acetylcysteine (NAC), N-acetylpenicillamine (NAP), penicillamine (PEN), mesna (MES), and tiopronin (TPR). The model systems contained isolated human erythrocytes (RBC), erythrocyte lysates (LYS) or erythrocyte membranes (MEM) exposed to tert-butyl hydroperoxide (t-BuOOH). Under the influence of RSH, a bimodal character of some experimental chemiluminescence curves was observed and the kinetic solution was considered as the sum of two logistic-exponential processes. These chemiluminescence changes probably reflected two connected processes--scavenging by RSH of the t-BuOOH-induced free radicals and simultaneous generation of thiol-derived secondary free radicals. Individual differences in thiols interaction showed a multivariate set of the kinetic curve descriptors. The Principal Component Analysis (PCA) well distinguished subsets of RSH influence in systems with RBC or LYS. Generally, the action of NAC was exclusively pro-oxidant in both systems, with RBC and LYS. The behaviour of MES or NAP in these systems was also pro-oxidant but many times less prominent than NAC. Under the influence of TPR a dramatic switch in the anti-oxidant effect was observed in system with RBC to very pro-oxidant effect in LYS. The influence of PEN was analogical to TPR but very weak. This experimental model together with kinetic solution of the unique bimodal chemiluminescence curves, and PCA, supply new insights to the dual (anti- and pro-oxidant) effects of thiol drugs under oxidative stress condition. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Amplified electrochemiluminescence of luminol based on hybridization chain reaction and in situ generate co-reactant for highly sensitive immunoassay.

    PubMed

    Xiao, Lijuan; Chai, Yaqin; Yuan, Ruo; Cao, Yaling; Wang, Haijun; Bai, Lijuan

    2013-10-15

    In this work, we described a simple and highly sensitive electrochemiluminescence (ECL) strategy for IgG detection. Firstly, L-cysteine functionalized reduced graphene oxide composite (L-cys-rGO) was decorated on the glassy carbon electrode (GCE) surface. Then anti-IgG was immobilized on the modified electrode surface through the interaction between the carboxylic groups of the L-cys-rGO and the amine groups in anti-IgG. And then biotinylated anti-IgG (bio-anti-IgG) was assembled onto the electrode surface based on the sandwich-type immunoreactions. By the conjunction of biotin and streptavidin (SA), SA was immobilized, which in turn, combined with the biotin labeled initiator strand (S1). In the presence of two single DNA strands of glucose oxidase labeled S2 (GOD-S2) and complementary strand (S3), S1 could trigger the hybridization chain reaction (HCR) among S1, GOD-S2 and S3. Herein, due to HCR, numerous GOD was efficiently immobilizated on the sensing surface and exhibited excellent catalysis towards glucose to in situ generate amounts of hydrogen peroxide (H2O2), which acted as luminol's co-reactant to significantly enhance the ECL signal. The proposed ECL immunosensor presented predominate stability and high sensibility for determination of IgG in the range from 0.1 pg mL(-1) to 100 ng mL(-1) with a detection limit of 33 fg mL(-1) (S/N=3). Additionally, the designed ECL immunosensor exhibited a promising application for other protein detection.

  6. Stainless Steel Electrode for Sensitive Luminol Electrochemiluminescent Detection of H2O2, Glucose, and Glucose Oxidase Activity.

    PubMed

    Kitte, Shimeles Addisu; Gao, Wenyue; Zholudov, Yuriy T; Qi, Liming; Nsabimana, Anaclet; Liu, Zhongyuan; Xu, Guobao

    2017-09-19

    Electrogenerated chemiluminescence (ECL) application of stainless steel, a robust and cost-effective material, has been developed for the first time. Type 304 stainless steel electrode shows appealing ECL performance in the luminol-H2O2 system. It enables the detection of H2O2 with a linear range from 1 to 1000 nM and a limit of detection of 0.456 nM [signal-to-noise ratio (S/N) = 3]. The ECL method based on type 304 stainless steel electrode is more sensitive, more cost-effective, and much simpler than other ECL methods reported before. Because the stainless steel electrode has excellent performance for H2O2 detection and H2O2 participates in many important enzymatic reactions, applications of stainless steel electrode-based ECL for detection of enzyme activities and enzyme substrates were further investigated by use of glucose oxidase (GODx) and glucose as representative enzyme and substrate. The concentrations of glucose and the activity of GODx were directly proportional to ECL intensities over a range of 0.1-1000 μM and 0.001-0.7 units/mL with limits of detection of 0.076 μM and 0.00087 unit/mL (S/N = 3), respectively. This method was successfully used for determining glucose in honey. Because of their remarkable performance and user-friendly features, stainless steel electrodes hold great promise in various electroanalytical applications, such as biosensing, disposable sensors, and wearable sensors.

  7. Synovial Fluid Findings and Demographic Analysis of Patients With Coexistent Intra-articular Monosodium Urate and Calcium Pyrophosphate Crystals.

    PubMed

    Heselden, Emilia L; Freemont, Antony J

    2016-03-01

    The aim of this study was to investigate the characteristics of arthritis in which monosodium urate (urate) and calcium pyrophosphate (CPP) crystals coexisted in synovial fluid (SF) to aid patient management and set a baseline from which to investigate the pathophysiological basis of an unusual coexistence of 2 disorders. Synovial fluid analyses of 33,000 patients were reviewed, identifying those containing urate and/or CPP crystals. Synovial fluid cell count and differential cell count, together with patient age and gender, were retrieved from a computerized database spanning 22 years of SF analysis. In 6983 consecutive SF samples containing crystals, CPP crystals were found in 3685 (53%), urate in 3127 (44.5%), and both in 171 (2.5%). These 171 cases were deemed to have a mixed crystal arthropathy (MCA). Patients with MCA were 77% male and 23% female, and the highest incidence was found in those aged 76 to 80 years.Most commonly (69.4% of cases of MCA), high numbers (>20/10 high-power field) of both crystals and an acute inflammatory cell count were found. In the remainder, other patterns of crystals and cells were observed, perhaps suggesting different clinical situations in which these crystals coexist. This study presents evidence showing that with careful microscopic analysis the coexistence of urate and CPP crystals in a single joint is found in 2.5% of cases of crystal arthritis. The different patterns of SF findings and patient demography described here are novel and might have implications for patient management.

  8. Protective Effect of Deer Bone Oil on Cartilage Destruction in Rats with Monosodium Iodoacetate (MIA)-Induced Osteoarthritis.

    PubMed

    Choi, Hyeon-Son; Im, Suji; Park, Je Won; Suh, Hyung Joo

    2016-01-01

    The anti-osteoarthritic activity of the methanol fraction of deer bone oil extract (DBO-M) was evaluated in interleukin (IL)-1β-inflamed primary rabbit chondrocytes and in rats with monosodium iodoacetate (MIA)-induced osteoarthritis. The active compound in DBO-M was analyzed using a direct infusion liquid chromatography quadrupole (LCQ) ion-trap electrospray ionization (ESI)-mass spectrometer (MS). DBO-M significantly suppressed the IL-1β-induced sulfated-glycosaminoglycan (s-GAG) release from chondrocyte, and lowered mRNA levels of the collagen-degrading enzymes matrix metalloproteinase (MMP)-1 and MMP-3 in a dose-dependent manner. Upon treatment with high doses of DBO-M, the levels of IL-1β, tumor necrosis factor (TNF)-α, and IL-6 decreased by around 40, 70, and 50%, respectively, compared to the control in the serum of rats with MIA-induced osteoarthritis. Bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) increased by over 40% in rats treated with DBO-M compared to the values reported for the MIA-treated control group, while trabecular separation (Tb.Sp) showed a significant decrease (ca. 38%), as confirmed through micro-computed tomography (CT) analysis of MIA-induced destruction of articular bones. Furthermore, direct infusion ESI-MS analysis showed that DBO-M contains gangliosides, which are glycosphingolipids with monosialic acid (GM3), as a major compound. Our results suggest that DBO-M effectively improves MIA-induced osteoarthritis by suppressing inflammatory responses, and that gangliosides could be one of the DBO-derived anti-inflammatory components.

  9. Biochemical alterations during the obese-aging process in female and male monosodium glutamate (MSG)-treated mice.

    PubMed

    Hernández-Bautista, René J; Alarcón-Aguilar, Francisco J; Del C Escobar-Villanueva, María; Almanza-Pérez, Julio C; Merino-Aguilar, Héctor; Fainstein, Mina Konigsberg; López-Diazguerrero, Norma E

    2014-06-27

    Obesity, from children to the elderly, has increased in the world at an alarming rate over the past three decades, implying long-term detrimental consequences for individual's health. Obesity and aging are known to be risk factors for metabolic disorder development, insulin resistance and inflammation, but their relationship is not fully understood. Prevention and appropriate therapies for metabolic disorders and physical disabilities in older adults have become a major public health challenge. Hence, the aim of this study was to evaluate inflammation markers, biochemical parameters and glucose homeostasis during the obese-aging process, to understand the relationship between obesity and health span during the lifetime. In order to do this, the monosodium glutamate (MSG) obesity mice model was used, and data were evaluated at 4, 8, 12, 16 and 20 months in both female and male mice. Our results showed that obesity was a major factor contributing to premature alterations in MSG-treated mice metabolism; however, at older ages, obesity effects were attenuated and MSG-mice became more similar to normal mice. At a younger age (four months old), the Lee index, triglycerides, total cholesterol, TNF-α and transaminases levels increased; while adiponectin decreased and glucose tolerance and insulin sensitivity levels were remarkably altered. However, from 16 months old-on, the Lee index and TNF-α levels diminished significantly, while adiponectin increased, and glucose and insulin homeostasis was recovered. In summary, MSG-treated obese mice showed metabolic changes and differential susceptibility by gender throughout life and during the aging process. Understanding metabolic differences between genders during the lifespan will allow the discovery of specific preventive treatment strategies for chronic diseases and functional decline.

  10. Changes in hippocampal synaptic functions and protein expression in monosodium glutamate-treated obese mice during development of glucose intolerance.

    PubMed

    Sasaki-Hamada, Sachie; Hojo, Yuki; Koyama, Hajime; Otsuka, Hayuma; Oka, Jun-Ichiro

    2015-05-01

    Glucose is the sole neural fuel for the brain and is essential for cognitive function. Abnormalities in glucose tolerance may be associated with impairments in cognitive function. Experimental obese model mice can be generated by an intraperitoneal injection of monosodium glutamate (MSG; 2 mg/g) once a day for 5 days from 1 day after birth. MSG-treated mice have been shown to develop glucose intolerance and exhibit chronic neuroendocrine dysfunction associated with marked cognitive malfunctions at 28-29  weeks old. Although hippocampal synaptic plasticity is impaired in MSG-treated mice, changes in synaptic transmission remain unknown. Here, we investigated whether glucose intolerance influenced cognitive function, synaptic properties and protein expression in the hippocampus. We demonstrated that MSG-treated mice developed glucose intolerance due to an impairment in the effectiveness of insulin actions, and showed cognitive impairments in the Y-maze test. Moreover, long-term potentiation (LTP) at Schaffer collateral-CA1 pyramidal synapses in hippocampal slices was impaired, and the relationship between the slope of extracellular field excitatory postsynaptic potential and stimulus intensity of synaptic transmission was weaker in MSG-treated mice. The protein levels of vesicular glutamate transporter 1 and GluA1 glutamate receptor subunits decreased in the CA1 region of MSG-treated mice. These results suggest that deficits in glutamatergic presynapses as well as postsynapses lead to impaired synaptic plasticity in MSG-treated mice during the development of glucose intolerance, though it remains unknown whether impaired LTP is due to altered inhibitory transmission. It may be important to examine changes in glucose tolerance in order to prevent cognitive malfunctions associated with diabetes.

  11. Antinociceptive action of diphenyl diselenide in the nociception induced by neonatal administration of monosodium glutamate in rats.

    PubMed

    Rosa, Suzan G; Quines, Caroline B; da Rocha, Juliana T; Bortolatto, Cristiani F; Duarte, Thiago; Nogueira, Cristina W

    2015-07-05

    Monosodium glutamate (MSG) is a neuroexcitatory amino acid commonly used as flavoring of foods. MSG neonatal administration to animals leads to behavioral and physiological disorders in adulthood, including increased pain sensitivity. This study aimed to investigate the effect of diphenyl diselenide (PhSe)2, an organoselenium compound with pharmacological properties already documented, on nociception induced by MSG. Newborn Wistar rats received 10 subcutaneous injections of MSG at a dose of 4.0g/kg or saline (once daily). At the 60th day of life, the rats were daily treated with (PhSe)2 (1mg/kg) or vehicle (canola oil) by the intragastric route for 7 days. The behavioral tests (locomotor activity, hot plate, tail-immersion and mechanical allodynia) were carried out. Ex vivo assays were performed in samples of hippocampus to determine Na(+), K(+)-ATPase and Ca(2+)-ATPase activities, cytokine levels and [(3)H]glutamate uptake. The results demonstrated that MSG increased nociception in the hot plate test and in the mechanical allodynia stimulated by Von-Frey hair but did not alter the tail immersion test. (PhSe)2 reversed all nociceptive behaviors altered by MSG. MSG caused an increase in Na(+),K(+)-ATPase and Ca(2+)-ATPase activities and in pro-inflammatory cytokine levels and a decrease in the anti-inflammatory cytokine and in the [(3)H]glutamate uptake. (PhSe)2 was effective in reversing all alterations caused by MSG. The results indicate that (PhSe)2 had a potential antinociceptive and anti-inflammatory action in the MSG model.

  12. Effects of ad libitum ingestion of monosodium glutamate on weight gain in C57BL6/J mice.

    PubMed

    Ren, Xueying; Ferreira, Jozélia G; Yeckel, Catherine W; Kondoh, Takashi; de Araujo, Ivan E

    2011-01-01

    Although the umami compound monosodium glutamate (MSG) is a widely used flavor enhancer, controversy still persists regarding the effects of MSG intake on body weight. It has been claimed, in particular, that chronic MSG intake may result in excessive body weight gain and obesity. In this study we assessed the effects of chronic (16 weeks) ad libitum MSG on body weight and metabolism of C57BL6/J mice. Adult male mice were divided in four experimental groups and fed with either a low-fat (LF) or high-fat (HF) diet and with either two bottles of plain water or one bottle containing 1% MSG and another one containing water according to a factorial design. Mice were monitored weekly for body weight and food/fluid intake for 15 weeks. At the end of the experiments, the circulating levels of leptin, insulin, total protein, total cholesterol, triglyceride, blood urea nitrogen, and non-esterified fatty acids were also analyzed. Our results show that MSG intake did not influence body weight in either LF or HF groups. Interestingly, although animals overall displayed strong preferences for MSG against water, preferences were relatively higher in LF compared to HF group. Consistent with the body weight data, while significant differences in leptin, insulin, total cholesterol, and non-esterified fatty acids were found between HF and LF groups, such an effect was not influenced by MSG intake. Finally, indirect calorimetry measurements revealed similar energy expenditure levels between animals being presented water only and MSG only. In summary, our data does not support the notion that ad libitum MSG intake should trigger the development of obesity or other metabolic abnormalities.

  13. Effect of NaCl/Monosodium Glutamate (MSG) Mixture on the Sensorial Properties and Quality Characteristics of Model Meat Products

    PubMed Central

    Chun, Ji-Yeon; Cho, Hyung-Yong; Min, Sang-Gi

    2014-01-01

    Sodium chloride is an important ingredient added to most of foods which contributes to flavor enhancement and food preservation but excess intake of sodium chloride may also cause various diseases such as heart diseases, osteoporosis and so on. Therefore, this study was carried out to investigate the effect of monosodium glutamate (MSG) as a salty flavor enhancer on the quality and sensorial properties of the NaCl/MSG complex and actual food system. For characterizing the spray-dried NaCl/MSG complex, surface dimension, morphology, rheology, and saltiness intensity were estimated by increasing MSG (0-2.0%) levels at a fixed NaCl concentration (2.0%). MSG levels had no effect of the characteristics of the NaCl/MSG complex, although the addition of MSG increased the surface dimension of the NaCl/MSG complex significantly (p<0.05). Furthermore, the effect of MSG on enhancing the salty flavor was not observed in the solution of the NaCl/MSG complex. In the case of an actual food system, model meat products (pork patties) were prepared by replacing NaCl with MSG. MSG enhanced the salty flavor, thereby increasing overall acceptability of pork patties. Replacement of NaCl with MSG (<1.0%) did not result in negative sensorial properties of pork patties, although quality deterioration such as high cooking loss was found. Nevertheless, MSG had a potential application in meat product formulation as a salty flavor enhancer or a partial NaCl replacer when meat products were supplemented with binding agents. PMID:26761490

  14. Obese women have lower monosodium glutamate taste sensitivity and prefer higher concentrations than do normal-weight women.

    PubMed

    Pepino, M Yanina; Finkbeiner, Susana; Beauchamp, Gary K; Mennella, Julie A

    2010-05-01

    The goal of this study was to determine whether obese women exhibit altered umami and sweet taste perception compared to normal-weight women. A total of 57 subjects (23 obese and 34 normal weight) participated in a 2-day study separated by 1 week. Half of the women in each group were evaluated using monosodium glutamate (MSG; prototypical umami stimulus) on the first test day and sucrose on the second test day; the order was reversed for the remaining women. We used two-alternative forced-choice staircase procedures to measure taste detection thresholds, forced-choice tracking technique to measure preferences, the general Labeled Magnitude Scale (gLMS) to measure perceived intensity of suprathreshold concentrations, and a triangle test to measure discrimination between 29 mmol/l MSG and 29 mmol/l NaCl. Obese women required higher MSG concentrations to detect a taste and preferred significantly higher MSG concentrations in a soup-like vehicle. However, their perception of MSG at suprathreshold concentrations, their ability to discriminate MSG from salt, and their preference for sucrose were similar to that observed in normal-weight women. Regardless of their body weight category, 28% of the women did not discriminate 29 mmol/l MSG from 29 mmol/l NaCl (nondiscriminators). Surprisingly, we found that, relative to discriminators, nondiscriminators perceived less savoriness when tasting suprathreshold MSG concentrations and less sweetness from suprathreshold sucrose concentrations but had similar MSG and sucrose detection thresholds. Taken together, these data suggest that body weight is related to some components of umami taste and that different mechanisms are involved in the perception of threshold and suprathreshold MSG concentrations.

  15. Forebrain Projections of Arcuate Neurokinin B Neurons Demonstrated by Anterograde Tract-Tracing and Monosodium Glutamate Lesions in the Rat

    PubMed Central

    Krajewski, Sally J.; Burke, Michelle C.; Anderson, Miranda J.; McMullen, Nathaniel T.; Rance, Naomi E.

    2010-01-01

    Neurokinin B (NKB) and kisspeptin receptor signaling are essential components of the reproductive axis. A population of neurons resides within the arcuate nucleus of the rat that expresses NKB, kisspeptin, dynorphin, NK3 receptors and estrogen receptor α. Here we investigate the projections of these neurons using NKB-immunocytochemistry as a marker. First, the loss of NKB-immunoreactive (ir) somata and fibers was characterized after ablation of the arcuate nucleus by neonatal injections of monosodium glutamate. Second, biotinylated dextran amine was injected into the arcuate nucleus and anterogradely labeled NKB-ir fibers were identified using dual-labeled immunofluorescence. Four major projection pathways are described: 1) Local projections within the arcuate nucleus bilaterally, 2) Projections to the median eminence including the lateral palisade zone, 3) Projections to a periventricular pathway extending rostrally to multiple hypothalamic nuclei, the septal region and BNST and dorsally to the dorsomedial nucleus and 4) Projections to a ventral hypothalamic tract to the lateral hypothalamus and medial forebrain bundle. The diverse projections provide evidence that NKB/kisspeptin/dynorphin neurons could integrate the reproductive axis with multiple homeostatic, behavioral and neuroendocrine processes. Interestingly, anterograde tract-tracing revealed NKB-ir axons originating from arcuate neurons terminating on other NKB-ir somata within the arcuate nucleus. Combined with previous studies, these experiments reveal a bilateral interconnected network of sex-steroid responsive neurons in the arcuate nucleus of the rat that express NKB, kisspeptin, dynorphin, NK3 receptors and ERα and project to GnRH terminals in the median eminence. This circuitry provides a mechanism for bilateral synchronization of arcuate NKB/kisspeptin/dynorphin neurons to modulate the pulsatile secretion of GnRH. PMID:20038444

  16. MyD88-dependent IL-1 receptor signaling is essential for gouty inflammation stimulated by monosodium urate crystals

    PubMed Central

    Chen, Chun-Jen; Shi, Yan; Hearn, Arron; Fitzgerald, Kate; Golenbock, Douglas; Reed, George; Akira, Shizuo; Rock, Kenneth L.

    2006-01-01

    While it is known that monosodium urate (MSU) crystals cause the disease gout, the mechanism by which these crystals stimulate this inflammatory condition has not been clear. Here we find that the Toll/IL-1R (TIR) signal transduction adaptor myeloid differentiation primary response protein 88 (MyD88) is required for acute gouty inflammation. In contrast, other TIR adaptor molecules, TIRAP/Mal, TRIF, and TRAM, are not required for this process. The MyD88-dependent TLR1, -2, -4, -6, -7, -9, and -11 and IL-18 receptor (IL-18R) are not essential for MSU-induced inflammation. Moreover, MSU does not stimulate HEK cells expressing TLR1–11 to activate NF-κB. In contrast, mice deficient in the MyD88-dependent IL-1R showed reduced inflammatory responses, similar to those observed in MyD88-deficient mice. Similarly, mice treated with IL-1 neutralizing antibodies also showed reduced MSU-induced inflammation, demonstrating that IL-1 production and IL-1R activation play essential roles in MSU-triggered inflammation. IL-1R deficiency in bone marrow–derived cells did not affect the inflammatory response; however, it was required in non–bone marrow–derived cells. These results indicate that IL-1 is essential for the MSU-induced inflammatory response and that the requirement of MyD88 in this process is primarily through its function as an adaptor molecule in the IL-1R signaling pathway. PMID:16886064

  17. Effect of alcoholic extract of Entada pursaetha DC on monosodium iodoacetate-induced osteoarthritis pain in rats

    PubMed Central

    Kumari, Rashmi R.; More, Amar S.; Gupta, Gaurav; Lingaraju, Madhu C.; Balaganur, Venkanna; Kumar, Pankaj; Kumar, Dinesh; Sharma, Anil K.; Mishra, Santosh K.; Tandan, Surendra Kumar

    2015-01-01

    Background & objectives: Osteoarthritis (OA) is a degenerative disease characterized by joint pain and progressive loss of articular cartilage. Entada pursaetha has been traditionally used in the treatment of inflammatory disease, liver ailment, etc. In this study we investigated suppressive effect of ethanolic extract of E. pursaetha (EPE) on monosodium iodoacetate (MIA)-induced osteoarthritis pain and disease progression by histopathological changes in joints in a rat model. Methods: OA was induced in right knee of rat by intra-articular injection of 3 mg of MIA and characterized by pathological progression of disease and pain of affected joint. Spontaneous movements, mechanical, thermal and cold sensitivity were monitored at days 0 (before drug and MIA injection), 7, 14 and 21 of MIA administration. EPE (30, 100 and 300 mg/kg), vehicle or etoricoxib (10 mg/kg; reference drug) were administered daily for 21 days by oral route. Results: EPE at various doses significantly reduced mechanical, heat, cold hyperalgesia and increased the horizontal and vertical movements in intra-articular MIA injected rats. EPE prevented the damage to cartilage structure and reduced the cellular abnormalities. Articular cartilage of rats treated with EPE at 300 mg/kg group was almost normal with well-developed smooth surface and chondrocytes were distributed individually or arranged in column. Interpretation & conclusions: The present findings showed that the EPE was not only able to mitigate pain and hyperalgesia but also inhibited MIA-induced cartilage degeneration in vivo. EPE may have the potential to become therapeutic modality in the treatment of osteoarthritis. However, further studies need to be done to confirm these findings in other models and clinical trials. PMID:26112847

  18. Biochemical Alterations during the Obese-Aging Process in Female and Male Monosodium Glutamate (MSG)-Treated Mice

    PubMed Central

    Hernández-Bautista, René J.; Alarcón-Aguilar, Francisco J.; Escobar-Villanueva, María Del C.; Almanza-Pérez, Julio C.; Merino-Aguilar, Héctor; Konigsberg Fainstein, Mina; López-Diazguerrero, Norma E.

    2014-01-01

    Obesity, from children to the elderly, has increased in the world at an alarming rate over the past three decades, implying long-term detrimental consequences for individual’s health. Obesity and aging are known to be risk factors for metabolic disorder development, insulin resistance and inflammation, but their relationship is not fully understood. Prevention and appropriate therapies for metabolic disorders and physical disabilities in older adults have become a major public health challenge. Hence, the aim of this study was to evaluate inflammation markers, biochemical parameters and glucose homeostasis during the obese-aging process, to understand the relationship between obesity and health span during the lifetime. In order to do this, the monosodium glutamate (MSG) obesity mice model was used, and data were evaluated at 4, 8, 12, 16 and 20 months in both female and male mice. Our results showed that obesity was a major factor contributing to premature alterations in MSG-treated mice metabolism; however, at older ages, obesity effects were attenuated and MSG-mice became more similar to normal mice. At a younger age (four months old), the Lee index, triglycerides, total cholesterol, TNF-α and transaminases levels increased; while adiponectin decreased and glucose tolerance and insulin sensitivity levels were remarkably altered. However, from 16 months old-on, the Lee index and TNF-α levels diminished significantly, while adiponectin increased, and glucose and insulin homeostasis was recovered. In summary, MSG-treated obese mice showed metabolic changes and differential susceptibility by gender throughout life and during the aging process. Understanding metabolic differences between genders during the lifespan will allow the discovery of specific preventive treatment strategies for chronic diseases and functional decline. PMID:24979131

  19. Synovial fluid proteins are required for the induction of interleukin-1β production by monosodium urate crystals.

    PubMed

    Scanu, A; Oliviero, F; Gruaz, L; Galozzi, P; Luisetto, R; Ramonda, R; Burger, D; Punzi, L

    2016-10-01

    Monosodium urate (MSU) crystal deposition in gouty joints promotes the release of inflammatory mediators, in particular interleukin (IL)-1β. The induction of IL-1β production by MSU crystals requires a co-stimulus. The objective of this study was to determine which part of the synovial fluid (SF) provides co-stimulation to MSU crystals to induce IL-1β in macrophages. The lipidic fraction (LF) and the protein fraction (PF) were isolated from the SF of patients with arthropathies. The PF was subfractionated according to different molecular weight (MW) ranges. THP-1 cells or human primary monocytes were stimulated with MSU crystals in the presence or absence of SF or SF fractions. IL-1β and IL-8 production and IL-1β mRNA expression were assessed by an enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qPCR). Exposure of monocytes/macrophages to MSU crystals alone induced the moderate release of IL-8 but not of IL-1β. The production of IL-1β required the presence of both SF from patients with inflammatory arthritis (SFi) and MSU crystals. SF from patients with non-inflammatory arthritis, that is patients with osteoarthritis (OA), did not affect the IL-1β production but slightly enhanced the secretion of IL-8. Both MSU crystals and SFi were required for the induction of the IL-1β transcript, which was not expressed in the presence of either stimulus alone. SFi fractionation demonstrated that the MSU crystal co-stimulus was contained in the PF of SFi with MW > 50 kDa but not in the LF. This study shows that the SF of inflammatory arthritis patients, including gout patients, contains proteins required for the induction of IL-1β by MSU crystals in macrophages whereas lipids are not involved.

  20. Dietary consumption of monosodium L-glutamate induces adaptive response and reduction in the life span of Drosophila melanogaster.

    PubMed

    Abolaji, Amos O; Olaiya, Charles O; Oluwadahunsi, Oluwagbenga J; Farombi, Ebenezer O

    2017-04-01

    Adaptive response is the ability of an organism to better counterattack stress-induced damage in response to a number of different cytotoxic agents. Monosodium L-glutamate (MSG), the sodium salt of amino acid glutamate, is commonly used as a food additive. We investigated the effects of MSG on the life span and antioxidant response in Drosophila melanogaster (D. melanogaster). Both genders (1 to 3 days old) of flies were fed with diet containing MSG (0.1, 0.5, and 2.5-g/kg diet) for 5 days to assess selected antioxidant and oxidative stress markers, while flies for longevity were fed for lifetime. Thereafter, the longevity assay, hydrogen peroxide (H2 O2 ), and reactive oxygen and nitrogen species levels were determined. Also, catalase, glutathione S-transferase and acetylcholinesterase activities, and total thiol content were evaluated in the flies. We found that MSG reduced the life span of the flies by up to 23% after continuous exposure. Also, MSG increased reactive oxygen and nitrogen species and H2 O2 generations and total thiol content as well as the activities of catalase and glutathione S-transferase in D. melanogaster (P < .05). In conclusion, consumption of MSG for 5 days by D. melanogaster induced adaptive response, but long-term exposure reduced life span of flies. This study may therefore have public health significance in humans, and thus, moderate consumption of MSG is advocated by the authors. Copyright © 2017 John Wiley & Sons, Ltd.