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1

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

PubMed

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 ?M histidine and 1.0-60 ?M lysine. PMID:23973428

Kugimiya, Akimitsu; Fukada, Rie; Funamoto, Daiki

2013-12-01

2

In vitro screening of Fe(2+) -chelating effect by a Fenton's reaction-luminol chemiluminescence system.  

PubMed

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??L) 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??M (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. PMID:24403191

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

2014-11-01

3

Chemiluminescence of luminol catalyzed by silver nanoparticles.  

PubMed

Silver nanoparticles (AgNPs) are synthesized by chemical reduction method and characterized by UV-vis spectra, transmission electron microscopy, and high performance particle sizer. We have found that AgNPs could enhance the chemiluminescence (CL) intensity of luminol-H(2)O(2) system. In this reaction, luminol intermediate is generated under alkaline condition on the surface of AgNPs in luminol-H(2)O(2) system and enhances CL intensity. To validate the reaction mechanism, AgNPs are bound with thioglycolic acid (Ag-HSCH(2)COOH) and then joined to BSA protein (Ag-BSA). We investigate the CL intensity in the presence of Ag-HSCH(2)COOH or Ag-BSA comparing with that in the presence of AgNPs and conclude the catalytic reaction take place on the surface of AgNPs. PMID:17681516

Chen, Hao; Gao, Feng; He, Rong; Cui, Daxiang

2007-11-01

4

Determination of ampicillin sodium using the cupric oxide nanoparticles-luminol-H2 O2 chemiluminescence reaction.  

PubMed

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. PMID:24254330

Iranifam, Mortaza; Kharameh, Merhnaz Khabbaz

2014-09-01

5

Determination of cysteine and glutathione based on the inhibition of the dinuclear Cu(II)-catalyzed luminol-H2O2 chemiluminescence reaction  

NASA Astrophysics Data System (ADS)

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.

Chaichi, Mohammad Javad; Ehsani, Mahjoobeh; Khajvand, Tahereh; Golchoubian, Hamid; Rezaee, Ehsan

2014-03-01

6

Determination of phenol by flow-injection with chemiluminescence detection based on the hemin-catalysed luminol-hydrogen peroxide reaction  

NASA Astrophysics Data System (ADS)

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.

Liu, Wenwen; Cao, Wei; Liu, Weihua; Du, Kang; Gong, Pixue

2012-01-01

7

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

PubMed

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. PMID:16521559

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

2006-01-01

8

Comparative studies of the chemiluminescent horseradish peroxidase-catalyzed peroxidation of acridan (GZ-11) and luminol reactions: Effect of pH and scavengers of reactive oxygen species on the light intensity of these systems  

Microsoft Academic Search

In this study, the chemiluminescent horseradish peroxidase\\/H2O2-catalysed oxidation of acridan (GZ-11) substrate was compared with the well-characterized light-producing luminol reaction. p-Iodophenol and p-phenylphenol were used as enhancers, respectively, for the luminol and acridan reactions. These two light-producing systems showed significant differences in relation to the effect of pH, as well as the effect of scavengers of reactive oxygen species, on

A. M. Osman; G. Zomer; C. Laane; R. Hilhorst

2000-01-01

9

Effect of gold nanoparticle as a novel nanocatalyst on luminol–hydrazine chemiluminescence system and its analytical application  

Microsoft Academic Search

In this work the catalytic role of unsupported gold nanoparticles on the luminol–hydrazine reaction is investigated. Gold nanoparticles catalyze the reaction of hydrazine and dissolved oxygen to generate hydrogen peroxide and also catalyze the oxidation of luminol by the produced hydrogen peroxide. The result is an intense chemiluminescence (CL) due to the excited 3-aminophthalate anion. In the absence of gold

A. Safavi; G. Absalan; F. Bamdad

2008-01-01

10

Dating skeletal remains with luminol-chemiluminescence. Validity, intra- and interobserver error  

Microsoft Academic Search

Amongst numerous other morphological, chemical, physical, and histological dating methods, the assessment of the chemiluminescence of weathered organic traces on bone finds by means of the luminol reaction is common practice. Opinion differs on the diagnostic value of this procedure for differentiating between historical and recent skeletonized human remains.

F. Ramsthaler; K. Kreutz; K. Zipp; M. A. Verhoff

2009-01-01

11

Synthesis and Characterization of Luminol Persulphate Chemiluminescence in Aqueous Amines  

NASA Astrophysics Data System (ADS)

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.

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

12

Towards chemiluminescence detection in micro-sequential injection lab-on-valve format: A proof of concept based on the reaction between Fe(II) and luminol in seawater.  

PubMed

Micro-sequential injection lab-on-valve (µSI-LOV) is a well-established analytical platform for absorbance and fluorescence based assays but its applicability to chemiluminescence detection remains largely unexplored. In this work, we describe a novel fluidic protocol and two distinct strategies for photon collection that enable chemiluminescence detection using µSI-LOV for the first time. To illustrate this proof of concept, we selected the reaction between Fe(II) and luminol and developed a preliminary protocol for Fe(II) determinations in acidified seawater. The optimized fluidic strategy consists of holding 100µL of the luminol reagent in a confined zone of the LOV and then displacing it with 50µL of sample while monitoring the chemiluminescent product. Detection is achieved using two strategies: one based on a bifurcated optical fiber and the other based on a customized detection window created by mounting a photomultiplier tube atop of the LOV device. We show that detection is possible using both strategies but that the window strategy yields significantly enhanced sensitivity (355×) due to the larger detection area. In our final experimental conditions and using window detection, it was possible to achieve a limit of detection (LOD) of 1nmolL(-1) and to quantify Fe(II) in acidified seawater samples up to 20.00nmolL(-1) with high precision (RSD<6%). These analytical features combined with the long-term stability of luminol solution and the full automation and low reagent consumption make this approach a promising analytical tool for shipboard analysis of Fe(II). The intrinsic capacity of the LOV to operate at a low microliter level and to handle solid phases also opens up a new avenue for chemiluminescence applications. Moreover, this contribution shows that LOV can be a universal platform for optical detection, capable of absorbance, fluorescence and luminescence measurements in a single instrument setup. PMID:25435235

Oliveira, Hugo M; Grand, Maxime M; Ruzicka, Jaromir; Measures, Christopher I

2015-02-01

13

Enhancing effect of hydrazine on chemiluminescence of luminol-H2O2 system  

NASA Astrophysics Data System (ADS)

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 ?g/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.

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

2013-05-01

14

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

NASA Astrophysics Data System (ADS)

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.

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

2011-06-01

15

Flow-injection chemiluminescence determination of dihydralazine sulfate in serum using luminol and diperiodatocuprate (III) system  

NASA Astrophysics Data System (ADS)

A novel flow-injection chemiluminescence (CL) method for the determination of dihydralazine sulfate (DHZS) is described. The method is based on the reaction of luminol and diperiodatocuprate (K 2[Cu(H 2IO 6)(OH) 2], DPC) in alkaline medium to emit CL, which is greatly enhanced by DHZS. The possible CL mechanism was first proposed based on the kinetic characteristic, CL spectrum and UV spectra. The optimum condition for the CL reaction was in detail studied using flow-injection system. The experiments indicated that under optimum condition, the CL intensity was linearly related to the concentration of DHZS in the range of 7.0 × 10 -9 to 8.6 × 10 -7 g mL -1 with a detection limit (3 ?) of 2.1 × 10 -9 g mL -1. The proposed method had good reproducibility with the relative standard deviation 3.1% ( n = 7) for 5.2 × 10 -8 g mL -1 of DHZS. This method has the advantages of simple operation, fast response and high sensitivity. The special advantage of the system is that very low concentration of luminol can react with DPC catalyzed by DHZS to get excellent experiment results. And CL cannot be observed nearly when luminol with same concentration reacts with other oxidants, so luminol-DPC system has higher selectivity than other luminol CL systems. The method has been successfully applied to determine DHZS in serum.

Yang, Chunyan; Zhang, Zhujun; Wang, Jinli

2010-01-01

16

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

PubMed

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. PMID:24455888

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

17

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)

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.

Geng, Hong; Meng, Ziqiang

2006-05-01

18

Modulatory role of nitric oxide on superoxide-dependent luminol chemiluminescence.  

PubMed

Reactive oxygen species are involved in luminol chemiexcitation induced in biological systems, but the contribution of nitrogen-derived oxidants in the process still remains unclear. Herein, we report that luminol chemiluminescence (LCL) induced by a superoxide (O2.-)- and hydrogen peroxide (H2O2)-generating system (2-25 mU/ml xanthine oxidase plus acetaldehyde and oxygen) was markedly inhibited by nitric oxide (.NO) added either as bolus (0-10 microM) or a continuous flow (0-10 microM/min). However, the inhibition of LCL was followed by an overshoot in light emission after most .NO was consumed or the infusion stopped and was due to reactions of remaining peroxynitrite, the product of the reaction between O2.- and .NO, with luminol. Nitric oxide also inhibited peroxynitrite- and glucose oxidase-induced LCL, but no overshoot was observed. On the other hand, a continuous flux of pure peroxynitrite, at 2 to 10 microM/min, induced LCL with quantum yields close to those obtained by identical micromolar fluxes of O2.-, while peroxynitrite formed from the decomposition of the sydnonimine SIN-1 yielded 76% of the chemiluminescence obtained with authentic peroxynitrite. Peroxynitrite-induced LCL was 80 and 55% inhibitable by SOD and catalase, respectively, showing that there were O2.- and H2O2-dependent routes of chemiexcitation. The hydroxyl radical scavengers dimethyl sulfoxide, mannitol, and ethanol and the metal chelator diethylenetriaminepentaacetic acid did not inhibit peroxynitrite-induced LCL while desferrioxamine was an efficient inhibitor of light emission by reaction with an activated state of peroxynitrous acid which is responsible of performing the initial one-electron oxidation of luminol. Our results are consistent with a dual role of .NO in O2.(-)-induced LCL: (I) formation of peroxynitrite which in turn promotes the light-emitting route and (II) reaction with luminol radical intermediates directing the system toward a dark pathway. These considerations are of critical importance when analyzing cell- and tissue-derived LCL in .NO-, O2.(-)-, and peroxynitrite-producing systems. PMID:8806769

Castro, L; Alvarez, M N; Radi, R

1996-09-01

19

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

PubMed

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 ?mol 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) (3?). 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 %. PMID:24566970

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

2014-06-01

20

Ferrous iron-induced luminol chemiluminescence: a method for hydroxyl radical study.  

PubMed

We have investigated the chemiluminescence signal of the ferrous iron in the presence of the luminol and lucigenin. Ferrous, but not ferric, iron produced a transient signal in the presence of luminol, but not lucigenin. Ferrous iron-induced luminol chemiluminescence was significantly inhibited in a concentration-dependent manner by superoxide dismutase (SOD) and catalase. Specific hydroxyl radical scavengers, mannitol and dimethyl sulfoxide (DMSO), also markedly attenuated the ferrous iron-induced chemiluminescence. Additionally, antioxidants, urate, ascorbate, and methionine produced concentration-dependent significant inhibitions in this chemiluminescence. These results show that the hydroxyl radical generation is dependent on simultaneous formation of superoxide and hydrogen peroxide (H2O2). Ferrous iron does not generate a chemiluminescence signal in the presence of lucigenin suggesting that the formation of a hydroxyl radical is responsible for the luminol chemiluminescence. Thus, the present study has established a simple and inexpensive cell-free screening method for monitoring the scavenging effects of drugs on the hydroxyl radical. PMID:9741393

Yildiz, G; Demiryürek, A T

1998-04-01

21

Effect of oxidatively modified and non-modified human serum albumin on luminol-dependent chemiluminescence of human peripheral blood leukocytes stimulated with opsonized zymosan.  

PubMed

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. PMID:25065314

Piryazev, A P; Azizova, A P; Aseichev, A V; Sergienko, V I

2014-07-01

22

Study of the enhanced chemiluminescence from the luminol-horseradish peroxidase-hydrogen peroxide- p-coumaric acid system at very short times: stopped flow selective determination of p-coumaric acid in beers  

Microsoft Academic Search

p-Coumaric acid has a greater enhancing effect on the chemiluminescence of the luminol-H2O2-horseradish peroxidase system, at low concentration, than other phenolic acids studied. We have used this effect to study the variations of the chemiluminescent signal with luminol, hydrogen peroxide, p-coumaric acid, horseradish peroxidase concentrations and pH, using the stopped-flow technique, by monitoring the initial reaction rate. The interference effects

F. García Sánchez; A. Navas Díaz; J. A. González García

1995-01-01

23

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

PubMed Central

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

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

1984-01-01

24

Electrochemical characterization of the clay-enhanced luminol ecl reaction  

Microsoft Academic Search

Clay modified electrodes were prepared with iron-containing clay particles (montmorillonite K10) and characterized for their ability to promote electrogenerated chemiluminescence (ecl) in a solution containing luminol and hydrogen peroxide. Electrochemical impedance spectroscopic (EIS) measurements showed that the charge-transfer resistance measured for the clay electrode decreased systematically with the addition of luminol or H2O2, leading to a linear relationship between the

Chih Sheng Ouyang; Chong Mou Wang

1999-01-01

25

Development of FIA equipped with a chemiluminescence detector using a mixed reagent of luminol and 1,10-phenanthroline.  

PubMed

We developed an FIA system equipped with a chemiluminescence detector using a mixed chemiluminescence reagent of luminol and 1,10-phenanthroline for the detection of metal ions and metal complexes. The carrier, mixed chemiluminescence reagent comprising luminol, 1,10-phenanthroline, and cethyltrimethylammonium bromide, and H2O2 solutions were fed by corresponding pumps at a definite flow rate. Sample solutions dissolving hematin, [Co(NH3)4(H2O)2]2(SO4)3, CuSO4, NiCl2, K3[Fe(CN)6], and K4[Fe(CN)6] were analyzed as models by the means of the present FIA system. Solutions of hematin, [Co(NH3)4(H2O)2]2(SO4)3, CuSO4, and NiCl2 were detected as positive peaks, as usual. The order of the catalytic activity of these samples for the present chemiluminescence reaction using the mixed chemiluminescence reagent was [Co(NH3)4(H2O)2]2(SO4)3 > hematin > CuSO4 > NiCl2. On the other hand, sample solutions of K3[Fe(CN)6] and K4[Fe(CN)6] were detected as negative peaks and were determined over the ranges of 1 x 10(-8) - 1 x 10(-6) M with a detection limit of 1 x 10(-8) M and 2 x 10(-8) - 4 x 10(-6) M with a detection limit of 2 x 10(-8) M, respectively. Their negative peaks were observed reproducibly with a relative standard deviation of 2 - 5%. PMID:12880085

Tsukagoshi, Kazuhiko; Tahira, Masayuki; Nakajima, Riichiro

2003-07-01

26

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

PubMed

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

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

27

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

NASA Astrophysics Data System (ADS)

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) ?5%. 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.

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

2013-12-01

28

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

PubMed

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. PMID:11754137

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

2001-01-01

29

Development of a highly sensitive chemiluminescence enzyme immunoassay using enhanced luminol as substrate.  

PubMed

In this study, a high sensitivity chemiluminescence enzyme immunoassay (CLEIA) based on novel enhancers was developed. Under optimal conditions, we developed an enhanced chemiluminescence reaction (ECR) catalyzed by horseradish peroxidase (HRP-C) in the presence of 3-(10'-phenothiazinyl) propane-1-sulfonate (SPTZ) and 4-morpholinopyridine (MORP) as enhancers. The limit of detection of the newly prepared chemiluminescent cocktail for HRP was 0.33?pg/well, which is lower than that of commercial Super Signal substrate. The results showed that this novel chemiluminescent cocktail can significantly increase the light output of HRP-catalyzed ECR, which can be translated into a corresponding improvement in sensitivity. Similar improvements were observed in CLEIA for the determination of chloramphenicol in milk. In addition, the ECR of N-azoles as secondary enhancer was also presented. PMID:23785024

Tao, Xiaoqi; Wang, Wenjun; Wang, Zhanhui; Cao, Xingyuan; Zhu, Jinghui; Niu, Lanlan; Wu, Xiaoping; Jiang, Haiyang; Shen, Jianzhong

2014-06-01

30

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

PubMed

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. PMID:24662755

Qi, Yingying; Li, Baoxin; Xiu, Furong

2014-07-15

31

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

NASA Astrophysics Data System (ADS)

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.

Qi, Yingying; Li, Baoxin; Xiu, Furong

2014-07-01

32

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

Microsoft Academic Search

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\\u000a been shown to be similar to the pH optimum value of horseradish peroxidase. Luminescence intensity changed when the concentration\\u000a of Tris-buffer was varied; maximum intensity

M. M. Vdovenko; R. Ullrich; M. Hofrichter; I. Yu. Sakharov

2010-01-01

33

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)

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 ?g for colorimetric detection and from 10 ng to 1.0 ?g 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.

He, Yi; Peng, Rufang

2014-11-01

34

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

PubMed

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 ?g for colorimetric detection and from 10 ng to 1.0 ?g 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. PMID:25327146

He, Yi; Peng, Rufang

2014-11-14

35

Chemiluminescent Reactions Catalyzed by Nanoparticles of Gold, Silver, and Gold/Silver Alloys  

NASA Astrophysics Data System (ADS)

Chemiluminescence (CL) reactions are catalyzed by metals nanoparticles, which display unique catalytic properties due to an increased surface area. The present study describes the catalytic effects of nanoparticles (NP) of silver, gold, and alloys of Au/Ag nanoparticles on the chemiluminescent reaction taking place between luminol and potassium ferricyanide. It was found that silver nanoparticles and alloy nanoparticles enhance the CL process when their sizes remained in the range of 30 nm to 50 nm. The data show that the intensity and rate of chemiluminescence were influenced by the mole fraction of gold and silver in the alloy. Data to this chemiluminescence reaction are modeled by a double exponential curve, which indicates that two competing processes are occurring.

Abideen, Saqib Ul

36

Comparative study on thiol drugs' effect on tert-butyl hydroperoxide induced luminol chemiluminescence in human erythrocyte lysate and hemoglobin oxidation.  

PubMed

The current studies have investigated the effect of heterocyclic drugs with the single thiol group (thiamazole, mercaptopurine) and dithiol aliphatic drugs (dimercaptosuccinic acid, dithiothreitol) under oxidative stress conditions, using tert-butyl hydroperoxide (t-BuOOH), in human erythrocyte lysate with the luminol-enhanced chemiluminescence technique. Knowing that oxidative processes induced by t-BuOOH are triggered by (oxy)hemoglobin (Hb), the effect of different thiol drugs (RSH) on isolated human Hb oxidation to methemoglobin (MHb) and hemichromes (HChr) was further considered. Three types of chemiluminescence curves, fitting to logistic-exponential model, have been revealed under influence of RSH. Structure of the data (MHb and HChr production, and free radical activity of RSH) in Principal Component Analysis visualization and kinetic profiles of chemiluminescence integrate information in terms of the diversity of RSH reaction mechanisms depending on the specific molecular context of the given thiol: aliphatic or aromatic nature as well as the number and position of the -SH groups in the molecule. The study conducted in presented in vitro systems indicates the potential role of thiol drugs mediated toxicity in an oxidative stress dependent mechanism. PMID:25308193

Sajewicz, Waldemar; Zalewska, Marta; Milnerowicz, Halina

2015-02-01

37

Study of the oscillation and luminol chemiluminescence in the H 2O 2-KSCN-CuSO 4-NaOH system  

NASA Astrophysics Data System (ADS)

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.

Kiatisevi, Supavadee; Maisch, Steffen

2010-10-01

38

Chemiluminescent detection of organic air pollutants  

SciTech Connect

Chemiluminescent reactions can be used for specific and highly sensitive detection of a number of air pollutants. Among these are chemiluminescent reactions of ozone with NO or organics and reactions of luminol with a variety of oxidants. Reported here are studies exploring (1) the use of the temperature dependence of the chemiluminescent reactions of ozone with organic pollutants as a means of differentiating types of hydrocarbon classes and (2) the use of luminol techniques to monitor atmospheric concentrations of nitrogen dioxide (NO{sub 2}) and organic oxidants, specifically peroxyacyl nitrates (PANs). Coupling gas chromatography to the chemiluminescent detectors allows the measurement of individual species at very low concentrations.

Marley, N.A.; Gaffney, J.S.; Chen, Yu-Harn

1996-04-01

39

Flow injection analysis of ketoprofen based on the order transform second chemiluminescence reaction  

NASA Astrophysics Data System (ADS)

This paper explores an order-transform-second-chemiluminescence (OTSCL) method combining the flow injection technique for the determination of ketoprofen. When ketoprofen solution was injected into the mixture after the end of the reaction of alkaline luminol and sodium periodate or sodium periodate solution was injected into the reaction mixture of ketoprofen and alkaline luminol, a new chemiluminescence (CL) reaction was initiated and strong CL signal was detected. A mechanism for the OTSCL has been proposed on the basis of the chemiluminescence kinetic characteristic, UV-visible absorption and chemiluminescent spectra. Under optimal experimental conditions, the CL response is proportional to the concentration of ketoprofen over the range of 2.0 × 10 -7 to 1.0 × 10 -5 mol/L with a correlation coefficient of 0.9950 and a detection limit of 8.0 × 10 -9 mol/L (3 ?). The relative standard deviation for 11 repetitive determinations of 1.0 × 10 -6 mol/L ketoprofen is 2.9%. The utility of this method was demonstrated by determining ketoprofen in pharmaceutical formulations without interference from its potential impurities.

Zhuang, Yafeng; Cao, Guiping; Ge, Chuanqin

2012-01-01

40

Luminol Test  

NSDL National Science Digital Library

Learners mix a solution containing luminol and copper with a fake blood solution. A chemical reaction between the luminol solution and fake blood (hydrogen peroxide) show learners a blue glow. Forensic scientists spray luminol onto surfaces at crime scenes to detect invisible blood stains. Luminol solution reacts with blood, changing the structure of the molecule and temporarily adding energy. This energy causes the luminol to glow. This activity is used in the Crime Science Chemistry unit in OMSI's Chemistry Lab. Supply estimates are for 100 learners. For safety reasons, this activity should be conducted as a demonstration for younger audiences.

Industry, Oregon M.

1997-01-01

41

Chemistry Central Journal Research article Chemiluminescence determination of surfactant Triton X-100 in environmental water with luminol-hydrogen peroxide system  

E-print Network

© 2009 Liu et al Background: The rapid, simple determination of surfactants in environmental samples is essential because of the extensive use and its potential as contaminants. We describe a simple, rapid chemiluminescence method for the direct determination of the non-ionic surfactant Triton X-100 (polyethylene glycol tert-octylphenyl ether) in environmental water samples. The optimized experimental conditions were selected, and the mechanism of the Luminol-H2O2-Triton X-100 chemiluminesence system was also studied. Results: The novel chemiluminescence method for the determination of non-ionic surfactant Triton X-100 was based on the phenomenon that Triton X-100 greatly enhanced the CL signal of the luminol-H2O2 system. The alkaline medium of luminol and the pH value obviously affected the results. Luminol concentration and hydrogen peroxide concentration also affected the results. The optimal conditions were: Na2CO3 being the medium, pH value 12.5, luminol concentration 1.0 × 10-4 mol L-1, H2O2 concentration 0.4 mol L-1. The possible mechanism was studied and proposed. Conclusion: Under the optimal conditions, the standard curve was drawn up and quotas were

Xiaoyu Liu; Aifang Li; Baohui Zhou; Chaokun Qiu; Hongmin Ren; Chaokun Qiu; Hongmin Ren

2009-01-01

42

Flow injection determination of p-aminophenol at trace level using inhibited luminol-dimethylsulfoxide-NaOH-EDTA chemiluminescence.  

PubMed

A novel flow injection procedure was developed for the determination of p-aminophenol (PAP) based on the inhibition by PAP of the chemiluminescence from luminol-dimethylsulfoxide (DMSO)-NaOH-EDTA system. The method has merits of higher sensitivity, wider linear range, simpler procedure, and a more rapid analyzing speed. It is applicable for the determination of PAP in the range of 2.5 x 10(-10)-5.0 x 10(-8) g mL(-1) with a detection limit of 1.9 x 10(-10) g mL(-1). The relative standard deviation (RSD) for 5.0 x 10(-9) g mL(-1) PAP is 0.78% (n=15). The method has been successfully used to determine PAP in industrial wastewaters and environmental waters. Additionally, the inhibition mechanism was also discussed briefly. PMID:15644248

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

2005-01-01

43

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

NASA Astrophysics Data System (ADS)

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.

Qi, Yingying; Li, Baoxin

2013-07-01

44

A discrepancy in superoxide scavenging activity between the ESR-spin trapping method and the luminol chemiluminescence method.  

PubMed

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. PMID:17587682

Sato, Emiko; Niwano, Yoshimi; Mokudai, Takayuki; Kohno, Masahiro; Matsuyama, Yukihiko; Kim, Daekyung; Oda, Tatsuya

2007-06-01

45

Electrogenerated Chemiluminescence Resonance Energy Transfer between Luminol and CdSe@ZnS Quantum Dots and Its Sensing Application in the Determination of Thrombin.  

PubMed

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. PMID:25361206

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

2014-11-18

46

Research and development of a luminol-carbon monoxide flow system  

NASA Technical Reports Server (NTRS)

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.

Thomas, R. R.

1977-01-01

47

Determination of dissolved Fe(II) in seawater of the western North Pacific with luminol chemiluminescence method  

NASA Astrophysics Data System (ADS)

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 Bering Sea than those in the western North Pacific, implying that the oxidation rates were controlled not only by water temperature but also by organic compounds, such as humic substances.

Obata, H.; Mase, A.; Gamo, T.; Nishioka, J.; Takeda, S.

2010-12-01

48

Use of the Attenuation of Luminol-Perborate Chemiluminescence with Flow Injection Analysis for the Total Antioxidant Activity in Tea Infusions, Wines, and Grape Seeds  

Microsoft Academic Search

This study establishes a simple and fast flow injection analysis methodology for the determination of the antioxidant activity\\u000a in wines, tea infusions, and grape seeds, based on the inhibition effect of their natural antioxidants on the Co(II)\\/EDTA-induced\\u000a luminol-perborate chemiluminescence. At the optimum operational conditions, the antioxidant activity was measured by plotting\\u000a the inhibition percentage vs logarithm of sample mass to

José Antonio Murillo Pulgarín; Luisa Fernanda García Bermejo; Armando Carrasquero Durán

49

Influence of polyclonal immunoglobulins on the polymorphonuclear leukocyte response to lipopolysaccharide of Salmonella enteritidis as measured with luminol-enhanced chemiluminescence.  

PubMed Central

In gram-negative sepsis, the activation of polymorphonuclear leukocytes (PMN) by lipopolysaccharide (LPS) and the resulting production of superoxide and other oxygen radicals may be an important cause of tissue damage. A suppression of the PMN response to LPS stimulation would be therapeutically beneficial. The aim of this study was to determine whether different polyclonal immunoglobulins (Igs; 5S-Ig, 7S-Ig, and 19S-Ig) influence the PMN response to LPS of Salmonella enteritidis in vitro. The respiratory burst activity of PMN was measured with luminol-enhanced chemiluminescence. After addition of a 5S-Ig solution containing F(ab')2 fragments of IgG and a 19S-Ig solution containing 12% polyclonal IgM, luminol-enhanced chemiluminescence was reduced by 27% (P < 0.05) and 46% (P < 0.005), respectively. However, after addition of a 7S-Ig solution containing polyclonal IgG, luminol-enhanced chemiluminescence was increased fourfold (P < 0.05). The results suggest that the influence of polyclonal Igs on PMN response to LPS stimulation is dependent on the Ig class, F(ab')2 fragments of IgG and IgM leading to LPS neutralization and IgG leading to the production of potentially toxic oxygen radicals. PMID:7927690

Wagner, D R; Heinrich, D

1994-01-01

50

Specificity of oxygen radical scavengers and assessment of free radical scavenger efficiency using luminol enhanced chemiluminescence.  

PubMed

The selective scavenging capacities of 19 important oxygen radical scavengers were determined by adding them individually to each of the four oxy radical standards, (superoxide, hydroxy, alkoxy and hydroperoxy, and singlet O2), calculating the percent chemiluminescence inhibited, and extrapolating O2 equivalents neutralized from baseline. The sensitivity (0.01 nm/ml) and selectivity of this method not only allows identification of individual oxygen free radical species but also quantitates the efficiency of free radical scavengers. PMID:2827676

Rao, P S; Luber, J M; Milinowicz, J; Lalezari, P; Mueller, H S

1988-01-15

51

Luminol-dependent chemiluminescence of human phagocyte cell lines: comparison between DMSO differentiated PLB 985 and HL 60 cells.  

PubMed

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. PMID:19291810

Ashkenazi, Avraham; Marks, Robert S

2009-01-01

52

Chemiluminescence determination of moxifloxacin in pharmaceutical and biological samples based on its enhancing effect of the luminol-ferricyanide system using a microfluidic chip.  

PubMed

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. PMID:23723140

Suh, Yeoun Suk; Kamruzzaman, Mohammad; Alam, Al-Mahmnur; Lee, Sang Hak; Kim, Young Ho; Kim, Gyu-Man; Dang, Trung Dung

2014-05-01

53

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

SciTech Connect

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.

Gaffney, J.S.; Marley, N.A. [Argonne National Lab., IL (United States). Environmental Research Div.; Drayton, P.J. [Univ. of Chicago, IL (United States). Dept. of Geophysical Sciences

1997-09-01

54

Luminol chemiluminescence in unbuffered solutions with a cobalt(II)-ethanolamine complex immobilized on resin as catalyst and its application to analysis.  

PubMed

Using a heterogeneous catalyst, Co(II)-ethanolamine complex sorbed on Dowex-50W resin, the chemiluminescence (CL) of luminol in unbuffered or weakly acidic solution was studied in the presence of H2O2. The maximum luminol CL wavelength at pH 5.7 was 448 nm, 23 nm longer than that in a basic solution (pH 10.5). Three different ligands, mono-, di-, and triethanolamine, and six transition metal ions, Co(II), Cu(II), Ni(II), Mn-(II), Fe(II), and Fe(III) were compared by CL measurements. The CL intensity decreased in the order mono- > di- > triethanolamine and Co(II) > Cu(II) > Ni(II) > Fe-(III) > Mn(II) > Fe(II). This heterogeneous CL system was developed as H2O2 and glucose flow-through sensors. Detection limits (S/N = 3) of H2O2 and glucose using Dowex-50W-X4-Co(II)-monoethanolamine as catalyst are 1 x 10(-7) M and 1 x 10(-6) M, respectively. On the basis of the studies of the CL, fluorescence, UV-vis and ESCA spectra and the effect of dissolved oxygen in luminol solution, a mechanism for CL emission in unbuffered solution was considered as the formation of a superoxide radical ion during the decomposition of H2O2 catalyzed by the Co(II)-ethanolamine immobilized resin. Then the superoxide radical ion acted on luminol and the CL was emitted. The applications of the proposed method to determine H2O2 in rainwater without any special pretreatment and glucose in human urine and orange juice samples give satisfactory results. PMID:11721898

Lin, J M; Shan, X; Hanaoka, S; Yamada, M

2001-11-01

55

Selective determination method for measurement of nitrite and nitrate in water samples using high-performance liquid chromatography with post-column photochemical reaction and chemiluminescence detection  

Microsoft Academic Search

A simple, sensitive and selective method for the simultaneous determination of nitrite and nitrate in water samples has been developed. The method is based on ion-exchange separation, online photochemical reaction, and luminol chemiluminescence detection. The separation of nitrite and nitrate was achieved using an anion-exchange column with a 20mM borate buffer (pH 10.0). After the separation, these ions were converted

Hitoshi Kodamatani; Shigeo Yamazaki; Keiitsu Saito; Takashi Tomiyasu; Yu Komatsu

2009-01-01

56

Determination of hydrogen peroxide concentrations by flow injection analysis based on the enhanced chemiluminescent reaction using peroxidase  

SciTech Connect

The technique of flow injection analysis was employed in the determination of hydrogen peroxide. The method was based on the chemiluminescence reaction of luminol with H{sub 2}O{sub 2} which is catalyzed by horseradish peroxidase and enhanced by p-iodophenol. Hydrogen peroxide was linearly detected in the range 10{sup {minus}6}M-10{sup {minus}4}M by measuring the maximum intensity of light emitted. The detection limit is about 1 10{sup {minus}6}M hydrogen peroxide. Transition metal cations at millimolar concentrations do not have any interference on the determination of hydrogen peroxide by FIA based on the enhanced chemiluminescent reaction. This technique is relatively rapid and simple, and permits measurement of up to 80 samples/hr using generally available equipment.

Eremin, S.A.; Vlasenko, S.B.; Osipov, A.P.; Eremina, I.D.; Egerov, A.M. (M.V. Lomonosov State Univ., Moscow (USSR))

1989-01-01

57

A simple chemiluminescence method for determination of chemical oxygen demand values in water  

Microsoft Academic Search

In this paper, a low cost chemiluminescence detector with a photodiode instead of photo-multiplier tube (PMT) was developed for environmental monitoring of water quality. Based on the chemiluminescent reaction of luminol–H2O2–Cr3+ system, light emission caused by luminol–H2O2–Cr3+ system was detected by the photodiode, and its intensity caused by the appearance of Cr3+ after samples digestion was proportional to the chemical

Yonggang Hu; Zeyu Yang

2004-01-01

58

Capillary Electrophoresis of Polyamines with Universal Indirect Chemiluminescence Detection, Using Cobalt (II) as a Probe Ion  

Microsoft Academic Search

Highly sensitive indirect chemiluminescence detection for capillary electrophoresis (CE) of polyamines was demonstrated in this paper. In the indirect chemiluminescence (CL) detection system, a strong and stable background CL signal can be generated by the luminol?hydrogen peroxide reaction catalyzed by cobalt (II) probe ion in the running buffer. Displacement of the cobalt (II) probe ion in the running buffer, by

Xiangyi Huang; Jicun Ren

2003-01-01

59

An optimized, sensitive and stable reduced graphene oxide-gold nanoparticle-luminol-H2O2 chemiluminescence system and its potential analytical application  

NASA Astrophysics Data System (ADS)

The chemiluminescence (CL) performance of luminol is improved using reduced graphene oxide/gold nanoparticle (rGO-AuNP) nano-composites as catalyst. To prepare this catalyst, we propose a linker free, one-step method to in-situ synthesize rGO-AuNP nano-composites. Various measurements are utilized to characterize the resulting rGO-AuNP samples, and it is revealed that rGO could improve the stability and conductivity. Furthermore, we investigate the CL signals of luminal catalyzed by rGO-AuNP. Afterwards, the size effect of particle and the assisted enhancement effect of rGO are studied and discussed in detail. Based on the discussion, an optimal, sensitive and stable rGO-AuNP-luminon-H2O2 CL system is proposed. Finally, we utilize the system as a sensor to detect hydrogen peroxide and organic compounds containing amino, hydroxyl, or thiol groups. The CL system might provide a more attractive platform for various analytical devices with CL detection in the field of biosensors, bioassays, and immunosensors.

Wang, Wen-Shuo; He, Da-Wei; Wang, Ji-Hong; Duan, Jia-Hua; Peng, Hong-Shang; Wu, Hong-Peng; Fu, Ming; Wang, Yong-Sheng; Zhang, Xi-Qing

2014-04-01

60

Red-shifted emission from 1,2-dioxetane-based chemiluminescent reactions.  

PubMed

Commercial chemiluminescent reagents emit across a broad portion of the electromagnetic spectrum (400-500?nm). A challenge to the use of chemiluminescence to monitor biological processes is the presence of interfering substances in the biological optical window. In the present study, longer wavelength emitting fluorophores (the organic dyes Alexa 568 and Alexa 647), and a semiconductor nanoparticle (QDOT800) were used to red-shift the emission from commercially available 1,2-dioxetane-based chemiluminescent substrate reactions. By adding non-conjugated fluorescent emitters into chemiluminescent reaction mixtures, an emission peak occurred at the predicted wavelength of the fluorescent emitter. The excitation and emission from QDOT800 was preserved in the presence of a 100?µm-thick glass barrier separating it from the chemiluminescent reaction components. The maximum tissue phantom penetration by QDOT800 emission was 8.5?mm; in comparison, the native chemiluminescent emission at 500?nm was unable to penetrate the thinnest tissue phantom of 2.5?mm. The described method for red-shifted emissions from chemiluminescent reactions does not require direct interaction between the chemiluminescent reaction and the fluorescent emitters. This suggests that the mechanism of chemiluminescent excitation of fluorophores and QDOT800 is not exclusive to chemiluminescence resonance energy transfer or sensitized chemiluminescence, but rather by broad energization from the native chemiluminescent emission. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24760607

Park, Jason Y; Gunpat, Joshua; Liu, Li; Edwards, Brooks; Christie, Alana; Xie, Xian-Jin; Kricka, Larry J; Mason, Ralph P

2014-09-01

61

High throughput chemiluminescence platform for evaluating antioxidative activity of total flavonoid glycosides from plant extracts  

Microsoft Academic Search

A high throughput chemiluminescence (CL) platform for rapidly evaluating antioxidant activity of total flavonoid glycosides from plant extracts was developed originally based on their inhibition effects on the CL reaction of 1,1-dipheny-2-picrylhydrazyl (DPPH)–luminol or H2O2–luminol system. With the method, total flavonoid glycosides extracts were screened through detecting the inhibited CL intensity, which was reversely correlative to antioxidant activity of the

Hong Yao; Bin Wu; Yiyu Cheng; Haibin Qu

2009-01-01

62

Sol–gel horseradish peroxidase biosensor for hydrogen peroxide detection by chemiluminescence  

Microsoft Academic Search

Horseradish peroxidase (HRP) was immobilized by microencapsulation in sol–gel crystals derived from tetramethyl orthosilicate. A sol–gel biosensor based on the chemiluminescence reaction of the hydrogen peroxide–luminol–HRP system was developed. Calibration plots for hydrogen peroxide have been established by chemiluminescence measurements in a cuvette and through an optical fibre modified at its end with the immobilized HRP gel. The detection limit

A Navas D??az; M. C Ramos Peinado; M. C Torijas Minguez

1998-01-01

63

A Multicommuted Flow Procedure for the Determination of Cholesterol in Animal Blood Serum by Chemiluminescence  

Microsoft Academic Search

An automatic flow procedure for cholesterol determination in animal blood serum using enzymatic reaction and detection by chemiluminescence is described. Cholesterol esterase and cholesterol oxidase were immobilized on glass beads packed into two mini-columns (15 mm × 5 mm), which were coupled to flow system. Produced H2O2 reacted with luminol produced chemiluminescence that was detected using a solid-state detector. The flow system comprised a

Cherrine K. Pires; Boaventura F. Reis; Cristiane X. Galhardo; Patrícia B. Martelli

2003-01-01

64

Development and application of a luminol-based nitrogen dioxide detector  

Microsoft Academic Search

An instrument for the continuous measurement of nitrogen dioxide (NOâ) 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 NOâ in alkaline aqueous solution. Development included the optimization of the cell design and the solution composition. Sodium sulfite (NaâSOâ) and methanol (CHâOH) were added to the solution to

Wendel

1985-01-01

65

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)

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.

Rezaei, B.; Ensafi, Ali A.; Zarei, L.

2012-05-01

66

Differences in the reactivity of phthalic hydrazide and luminol with hydroxyl radicals.  

PubMed

The reactivity of 5-amino-2,3-dihydro-phthalazine-1,4-dione (luminol) and phthalic hydrazide with hydroxyl radicals was studied. HO*-radicals were generated by the Fenton reaction as well as by water radiolysis. Both luminol and phthalic hydrazide react with hydroxyl radicals under intense chemiluminescence (CL) emission. However, exclusively the CL arising from phthalic hydrazide oxidation can be quenched by competition (e.g. by the addition of carbohydrates), whereas luminol CL is enhanced. The reactivities of both compounds with HO*-radicals were further studied by time-resolved spectroscopy (pulse radiolysis), competition methods, NMR spectroscopy and mass spectrometry. Whereas only slight differences were detectable by pulse radiolysis, the analysis of competition kinetics in the presence of p-nitroso-dimethylaniline (NDMA) gave a two-fold-enhanced reactivity for luminol (4.8 x 10(9) l mol(-1) s(-1)) in comparison to phthalic hydrazide (2.0 x 10(9) l mol(-1) s(-1)). NMR and mass spectrometric analyses revealed significant differences in the reactivity of HO*-radicals: whereas in luminol solutions hydroxylation of the aromatic ring system predominated, hydroxylated products were not detectable upon irradiation of phthalic hydrazide. A hypothetical mechanism is proposed which may explain the observed differences. PMID:10193573

Schiller, J; Arnhold, J; Schwinn, J; Sprinz, H; Brede, O; Arnold, K

1999-01-01

67

Determination of phenolic compounds and their antioxidant activity in Erigeron acris L. extracts and pharmaceutical formulation by flow injection analysis with inhibited chemiluminescent detection  

Microsoft Academic Search

It was found that the chemiluminescence (CL) produced from the reaction of luminol with iodine in the alkaline medium was strongly inhibited by plant phenolic compounds. Based on this finding, a new flow injection CL method was developed for the determination of caffeic acid and 6?-caffeoylerigeroside. The latter compound was isolated for the first time from Erigeron acris L. herb.

Edyta Nalewajko-Sieliwoniuk; Jolanta Nazaruk; Ewelina Antypiuk; Anatol Koj?o

2008-01-01

68

Development of a chemiluminescent and bioluminescent system for the detection of bacteria in wastewater effluent  

NASA Technical Reports Server (NTRS)

Automated chemiluminescent and bioluminescent sensors were developed for continuous monitoring of microbial levels in wastewater effluent. Development of the chemiluminescent system included optimization of reagent concentrations as well as two new techniques which will allow for increased sensitivity and specificity. The optimal reagent concentrations are 0.0025 M luminol and 0.0125 M sodium perborate in 0.75N sodium hydroxide before addition of sample. The methods developed to increase specificity include (1) extraction of porphyrins from bacteria collected in a filter using 0.1N NaOH - 50 percent Ethanol, and (2) use of the specific reaction rate characteristics for the different luminol catalysts. Since reaction times are different for each catalyst, the reaction can be made specific for bacteria by measuring only the light emission from the particular reaction time zone specific for bacteria. Developments of the bioluminescent firefly luciferase system were in the area of flow system design.

Thomas, R. R.

1975-01-01

69

Measurement of product alignment in beam-gas chemiluminescent reactions  

E-print Network

- rectional properties of chemical reaction is required to understand the balance sheet for conservation polarization. I. INTRODUCTION Our current understanding of chemical reactions is based primarily

Zare, Richard N.

70

Short-Time-Response measurements of nitrogen dioxide and peroxyacetyl nitrate by fast capillary gas chromatography with luminol detection.  

SciTech Connect

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).

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

2000-12-07

71

Increasing the specificity of the forensic luminol test for blood.  

PubMed

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. PMID:11400264

Quickenden, T I; Cooper, P D

2001-01-01

72

Compact polytetrafluoroethylene assembly-type capillary electrophoresis with chemiluminescence detection.  

PubMed

We have developed a compact polytetrafluoroethylene (PTFE) assembly-type capillary electrophoresis with chemiluminescence (CL) detection system. Luminol-microperoxidase-hydrogen peroxide chemiluminescence reaction was adopted. The device is rectangular in shape (60 mm x 40 mm x 30 mm) and includes three reservoirs (sample, migration buffer, and detection reservoirs) with electrodes. The detection reservoir includes an optical fiber to transport light at the capillary tip to a photomultiplier tube. Isoluminol isothiocyanate (ILITC) was analyzed as a model using this device with fused-silica or polytetrafluoroethylene capillary tubes 10 cm in length. We also used the sample reservoir as a reactor for an immune reaction between anti-human serum albumin immobilized on glass beads and isoluminol isothiocyanate-labeled human serum albumin. The present polytetrafluoroethylene assembly with the capillary tube was useful as a palm-sized analysis device for separation and detection, as well as a reactor. PMID:16870196

Tsukagoshi, Kazuhiko; Ishida, Shingo; Oda, Yuichi; Noda, Keiichi; Nakajima, Riichiro

2006-08-25

73

Chemiluminescent logic gates based on functionalized gold nanoparticles/graphene oxide nanocomposites.  

PubMed

Label-free logic gates (AND, OR, and INHIBIT) based on chemiluminescence (CL) as new optical readout signal have been developed by taking advantage of the unique CL activity of luminol- and lucigenin-functionalized gold nanoparticles/graphene oxide (luminol-lucigenin/AuNPs/GO) nanocomposites. It was found that Fe(2+) ions could induce the CL emission of luminol-lucigenin/AuNPs/GO nanocomposites in alkaline solution. On this basis, by using Fe(2+) ions and NaOH as the inputs and the CL signal as the output, an AND logic gate was fabricated. When the initial reaction system contained luminol-lucigenin/AuNPs/GO nanocomposites and NaOH, either Fe(2+) ions or Ag(+) ions could react with the luminol-lucigenin/AuNPs/GO nanocomposites to produce a strong CL emission. This result was used to design an OR logic gate using Fe(2+) ions and Ag(+) ions as the inputs and CL signal as the output. Moreover, two INHIBIT logic gates for Fe(2+) and Ag(+) were also developed using by NaClO and L-cysteine as their CL inhibitors, respectively. Furthermore, the proposed logic gates were successfully used to detect Fe(2+), Ag(+), and L-cysteine, respectively. The developed logic gates may find future applications in sensing, clinical diagnostics, and environmental monitoring. PMID:23963613

He, Yi; Cui, Hua

2013-09-27

74

Chemiluminescence: An Illuminating Experiment  

ERIC Educational Resources Information Center

Describes an experiment in which luminescence is observed during a reaction between sodium borohydride and trisbipyridalruthenium (III). Includes a discussion of the theory of chemiluminescence. (MLH)

Gafney, Harry D.; Adamson, Arthur W.

1975-01-01

75

Chemiluminescence of firefly luciferin without enzyme.  

PubMed

We have been able to produce chemiluminescence in firefly luciferin without utilizing the enzyme luciferase. Following the analogous mechanism of the chemiluminescence of luminol in the organic solvent dimethyl sulfoxide, we have prepared synthetically the methyl ester of luciferin, the phosphate ester of luciferin and luciferyl adenylate by condensation in dimethyl sulfoxide with Khorana's reagent, dicyclohexylcarbodiimide and diazomethane, phosphoric acid, and adenylic acid respectively. These compounds in dimethyl sulfoxide in the presence of base emit a bright chemiluminescence. Like in vitro enzymatic bioluminescence, the luciferyl adenylate. chemiluminescence emission spectrum is dependent upon pH. PMID:13992711

SELIGER, H H; McELROY, W D

1962-11-01

76

Isoprinosine stimulates granulocyte chemiluminescence and inhibits monocyte chemiluminescence in vitro.  

PubMed

Isoprinosine may delay disease progression in human immunodeficiency virus infection, presumably through modulation of lymphocyte function. However, the influence of isoprinosine on phagocyte function is largely unknown. This study describes the effects of isoprinosine and azidothymidine on phagocyte chemiluminescence and migration. Incubation with isoprinosine concentrations of 250 micrograms/ml and above increased the chemiluminescence of granulocytes. Random migration of granulocytes was decreased at isoprinosine concentrations of 50 micrograms/ml and higher, but chemotaxis was not affected. Azidothymidine exerted no effect on the chemiluminescence or migration of granulocytes. For monocytes, luminol-enhanced chemiluminescence was reduced at isoprinosine concentrations of 250 micrograms/ml and above, whereas migration was not affected. These findings suggest that the immunomodulatory properties of isoprinosine may extend to phagocytic cells. This may be of significance in the treatment of immunodeficiency states. PMID:7516672

Flø, R W; Naess, A; Albrektsen, G; Solberg, C O

1994-04-01

77

Chemiluminescence accompanied by the reaction of acridinium ester and manganese (II).  

PubMed

An acridinium ester (AE) alkaline solution can react with Mn(II) to generate a strong chemiluminescence (CL) centered at 435?nm. The effects of reaction conditions such as pH and Mn(II) concentration on CL intensity were examined. In order to explore the CL mechanism, the effect of oxygen on the CL reaction was examined and an X-ray photoelectron spectroscopy study of the reaction precipitate was carried out. The results indicated that oxygen participated in the CL reaction and Mn(IV) was the primary product in the system. A possible mechanism was proposed that involved two pathways: (1) dissolved oxygen was reduced to reactive oxygen radicals by Mn(II), these reactive intermediates then reacted with AE to produce excited state acridone; (2) Mn(II) could reduce AE to partly reduced AE, which then reacted with oxygen to form excited state acridone. The reactions of other metal ions with AE were also tested, and only Mn(II) was shown to trigger strong CL emission of AE, which indicated that the system had good selectivity for Mn(II). Copyright © 2014 John Wiley & Sons, Ltd. PMID:24677387

Ren, Lingling; Cui, Hua

2014-11-01

78

Enhancement of chemiluminescence for vitamin B12 analysis.  

PubMed

In the current article, chemiluminescence (CL) from the vitamin B(12) and luminol reaction was studied under alkaline conditions to develop a sensitive analytical method for vitamin B(12) using the carbonate enhancement effect. The method was successfully applied to the determination of vitamin B(12) in vitamin B(12) tablets, multivitamin capsules, and vitamin B(12) injections. Experimental parameters were optimized, including luminol concentration, urea-hydrogen peroxide (urea-H(2)O(2)) concentration, effect of pH, and sequence of addition of reactants for obtaining maximum CL, which was not explored previously. The limit of detection was 5 pg/ml, and the linear range was 10 pg/ml to 1 microg/ml with a regression coefficient of R(2)=0.9998. The importance of these experimental parameters and the carbonate enhancement effect is discussed based on the knowledge of the mechanism of oxidation of luminol and decomposition of urea-H2O2 in the presence of vitamin B(12). Extraction of vitamin B(12) was carried out, and the observed recovery was 97-99.2% with a relative standard deviation in the range of 0.30-1.09%. The results obtained were compared with those of the flame atomic absorption spectrometry method. PMID:19250918

Kumar, Sagaya Selva; Chouhan, Raghuraj Singh; Thakur, Munna Singh

2009-05-15

79

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

NASA Technical Reports Server (NTRS)

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.

Thomas, R. R.

1976-01-01

80

Comparison of Uric Acid Quantity with Different Food in Human Urine by Flow Injection Chemiluminescence Analysis  

PubMed Central

Based on the inhibitory effect of uric acid (UA) on luminol-Co2+ chemiluminescence (CL) system, a sensitive method for the determination of UA at nanomolar level by flow injection (FI) CL was proposed. The proposed method was successfully applied to real-time monitoring of UA excretion in human 24?h urine with different food intake, showing that meats, vegetables, and porridge intake caused differential UA excretions of 879, 798, and 742?mg, respectively. It was also found that UA concentrations in urine under the three kinds of food intake simultaneously reached maximum at 2?h after meals with the values of 417, 318, and 288??g?mL?1, respectively. The UA concentration in human serum was also determined by this approach, and the possible mechanism of luminol-Co2+-UA?CL reaction was discussed in detail. PMID:24251067

Wang, Jiajia; Tan, Xijuan; Song, Zhenghua

2013-01-01

81

Chemiluminescence flow sensor for the determination of ascorbic acid with immobilized reagents.  

PubMed

A novel flow sensor based on chemiluminescence (CL) for the determination of ascorbic acid has been proposed. The analytical reagents, luminol and ferricyanide, were both immobilized on an anion-exchange resin column. The CL signal produced by the reaction between luminol and ferricyanide, which were eluted from the column through sodium phosphate injection, was decreased in the presence of ascorbic acid. The CL emission intensity was linear with ascorbic acid concentration in the range 0.01-0.8 mug ml(-1); the detection limit was 5.5 x 10(-3) mug ml(-1). The whole process, including sampling and washing, could be completed in 1 min with a relative standard deviation of less than 5%. The sensor could be reused more than 100 times and has been applied successfully to the analysis of ascorbic acid in pills and vegetables. PMID:18966471

Zhang, Z; Qin, W

1996-01-01

82

A Greener Chemiluminescence Demonstration  

ERIC Educational Resources Information Center

Because they are dramatic and intriguing, chemiluminescence demonstrations have been used for decades to stimulate interest in chemistry. One of the most intense chemiluminescent reactions is the oxidation of diaryl oxalate diesters with hydrogen peroxide in the presence of a fluorescer. In typical lecture demonstrations, the commercially…

Jilani, Osman; Donahue, Trisha M.; Mitchell, Miguel O.

2011-01-01

83

Synchronization of oscillatory chemiluminescence with pulsed light irradiation  

NASA Astrophysics Data System (ADS)

A chemical oscillator, the H2O2-KSCN-CuSO4-NaOH system, generates an oscillatory chemiluminescence when luminol is added to this system. Attempts were made to synchronize the oscillatory chemiluminescence with pulsed light irradiation. A period of the chemical oscillation became shorter by the irradiation of white and blue color light, while the oscillatory behavior was scarcely influenced by the irradiation of red light. Pulsed red and white or blue lights were irradiated on either the non-luminol or luminol-added H2O2-KSCN-CuSO4-NaOH system. Synchronization of the chemical oscillation was achieved for 25-30 min in the luminol-added system.

Takayama, Shunsuke; Okano, Kunihiko; Asakura, Kouichi

2013-01-01

84

Diagnostic validity of the chemiluminescent method compared to polymerase chain reaction for hepatitis B virus detection in the routine clinical diagnostic laboratory  

PubMed Central

Background: Hepatitis B virus (HBV) is the most common significant chronic viral infection world-wide. Hepatitis B surface antigen (HBsAg) has been the principal target for laboratory testing to identify active infection by HBV. We aimed to find out diagnostic validity of the Liaison chemiluminescent method compared to the polymerase chain reaction (PCR) method for HBV detection in the routine clinical diagnostic laboratory. Materials and Methods: From 350 patients suspicious of having infection with HBV, serum samples were separated and used for testing HBsAg by two methods of Liaison chemiluminescent immunoassay, with HBsAg confirmatory test and PCR method. Results: According to the PCR results as assumed as gold standard method with 100% sensitivity and specificity, detection rate sensitivity of chemiluminescent with confirmatory test was 96% and its specificity was 100%, and for chemiluminescent without confirmatory test sensitivity and specificity were 100% and 70%, respectively. Also for chemiluminescent with confirmatory test, positive predictive value (PPV) was 100% and its negative predictive value (NPV) was 97%, compared to chemiluminescent without confirmatory test with PPV and NPV equal to 71% and 100%, respectively. Conclusions: It is possible to conclude that in the majority of the HBV cases, the diagnostic value of chemiluminescent method compared to the PCR method is acceptable, except in low indexes positive cases that need further investigation with the PCR method. PMID:24949287

Khadem-Ansari, Mohammad-Hassan; Omrani, Mir-Davood; Rasmi, Yousef; Ghavam, Arsalan

2014-01-01

85

Measurement of salivary cortisol by a chemiluminescent organic-based immunosensor.  

PubMed

A highly sensitive chemiluminescent immunoassay (CLIA) using a sensitive organic photodetector was developed to detect human cortisol, an important biomarker for stress-related diseases. The developed CLIA was performed onto gold-coated glass chips, on which anti-cortisol antibodies were immobilised and chemiluminescent horseradish peroxidase-luminol-peroxide reactions were generated. Using cortisol-spiked artificial saliva samples, the CLIA biosensor showed a linear range of detection between 0.1 ng/mL and 175 ng/mL and a detection limit of 80 pg/mL. The sensor response was highly specific to cortisol and did not vary significantly between assays. The results indicate the potential clinical application of the CLIA sensor. Furthermore, the simple layered structure of the organic photodetector may encourage the realisation of integrated optical biosensors for point-of-use measurement of salivary cortisol levels. PMID:24211877

Pires, N M M; Dong, T

2014-01-01

86

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

PubMed

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. PMID:24491787

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

2014-02-17

87

Method and apparatus for eliminating luminol interference material  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

88

Highly sensitive homogenous chemiluminescence immunoassay using gold nanoparticles as label.  

PubMed

Homogeneous immunoassay is becoming more and more attractive for modern medical diagnosis because it is superior to heterogeneous immunoassay in sample and reagent consumption, analysis time, portability and disposability. Herein, a universal platform for homogeneous immunoassay, using human immunoglobulin G (IgG) as a model analyte, has been developed. This assay relies upon the catalytic activity of gold nanoparticles (AuNPs) on luminol-AgNO3 chemiluminescence (CL) reaction. The immunoreaction of antigen and antibody can induce the aggregation of antibody-functionalized AuNPs, and after aggregation the catalytic activity of AuNPs on luminol-AgNO3 CL reaction is greatly enhanced. Without any separation steps, a CL signal is generated upon addition of a trigger solution, and the CL intensity is directly correlated to the quantity of IgG. The detection limit of IgG was estimated to be as low as 3pg/mL, and the sensitivity was better than that of the reported AuNPs-based CL immunoassay for IgG. PMID:24835732

Luo, Jing; Cui, Xiang; Liu, Wei; Li, Baoxin

2014-10-15

89

Highly sensitive homogenous chemiluminescence immunoassay using gold nanoparticles as label  

NASA Astrophysics Data System (ADS)

Homogeneous immunoassay is becoming more and more attractive for modern medical diagnosis because it is superior to heterogeneous immunoassay in sample and reagent consumption, analysis time, portability and disposability. Herein, a universal platform for homogeneous immunoassay, using human immunoglobulin G (IgG) as a model analyte, has been developed. This assay relies upon the catalytic activity of gold nanoparticles (AuNPs) on luminol-AgNO3 chemiluminescence (CL) reaction. The immunoreaction of antigen and antibody can induce the aggregation of antibody-functionalized AuNPs, and after aggregation the catalytic activity of AuNPs on luminol-AgNO3 CL reaction is greatly enhanced. Without any separation steps, a CL signal is generated upon addition of a trigger solution, and the CL intensity is directly correlated to the quantity of IgG. The detection limit of IgG was estimated to be as low as 3 pg/mL, and the sensitivity was better than that of the reported AuNPs-based CL immunoassay for IgG.

Luo, Jing; Cui, Xiang; Liu, Wei; Li, Baoxin

2014-10-01

90

Development and application of a luminol-based nitrogen dioxide detector  

SciTech Connect

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.

Wendel, G.J.

1985-01-01

91

Chemiluminescence: applications for the clinical laboratory.  

PubMed

The chemical features and applications of chemiluminescence are reviewed, with special attention to bacterial and firefly bioluminescence and to uses of chemiluminescence in direct substrate assays, enzyme assays, solid-phase reactions, and immunoassays. PMID:6321319

Boeckx, R L

1984-02-01

92

A chemiluminescence biochemical oxygen demand measuring method.  

PubMed

A new chemiluminescence biochemical oxygen demand (BOD(CL)) determining method was studied by employing redox reaction between quinone and Baker's yeast. The measurement was carried out by utilizing luminol chemiluminescence (CL) reaction catalyzed by ferricyanide with oxidized quinone of menadione, and Saccharomyces cerevisiae using a batch-type luminometer. In this study, dimethyl sulfoxide was used as a solvent for menadione. After optimization of the measuring conditions, the CL response to hydrogen peroxide in the incubation mixture had a linear response between 0.1 and 100 microM H2O2 (r2=0.9999, 8 points, n=3, average of relative standard deviation; R.S.D.(av)=4.22%). Next, a practical relationship between the BOD(CL) response and the glucose glutamic acid concentration was obtained over a range of 11-220 mg O2 L(-1) (6 points, n=3, R.S.D.(av) 3.71%) with a detection limit of 5.5 mg O2 L(-1) when using a reaction mixture and incubating for only 5 min. Subsequently, the characterization of this method was studied. First, the BOD(CL) responses to 16 pure organic substances were examined. Second, the influences of chloride ions, artificial seawater, and heavy metal ions on the BOD(CL) response were investigated. Real sample measurements using river water were performed. Finally, BOD(CL) responses were obtained for at least 8 days when the S. cerevisiae suspension was stored at 4 degrees C (response reduction, 69.9%; R.S.D. for 5 testing days, 18.7%). BOD(CL) responses after 8 days and 24 days were decreased to 69.9% and 35.8%, respectively, from their original values (R.S.D. for 8 days involving 5 testing days, 18.7%). PMID:17936112

Nakamura, Hideaki; Abe, Yuta; Koizumi, Rui; Suzuki, Kyota; Mogi, Yotaro; Hirayama, Takumi; Karube, Isao

2007-10-17

93

Chemiluminescence of Ru(bpy) 3 2+* in the reaction of electron transfer from Ph 3 CNa to Ru(bpy) 3 3+ in a solution  

Microsoft Academic Search

Conditions for the generation of the Ru(bpy)3\\u000a 3+ complex in organic solvents (Me3CN or MeNO2) in the presence of small amounts of H2SO4 were found. Chemiluminescence was observed in the reaction of Ru(bpy)3\\u000a 3+ with Ph3Na in a THF-MeCN mixture. The chemiluminescence emitter was identified as Ru(bpy)3\\u000a 2+*. This emitter forms in the excited state in the elementary reaction of

R. G. Bulgakov; S. P. Kuleshov; T. S. Usmanov; B. A. Mustafin

1999-01-01

94

Chemiluminescent detection of cell apoptosis enzyme by gold nanoparticle-based resonance energy transfer assay.  

PubMed

We report a new chemiluminescence resonance energy transfer (CRET) technique, using gold nanoparticles (AuNPs) as efficient energy acceptor, for homogeneous measurement of cell apoptosis enzyme with high sensitivity. In the design of the CRET system, we chose the highly sensitive chemiluminescence (CL) reaction between luminol and hydrogen peroxide catalysed by horseradish peroxidase (HRP) because the CL spectrum of luminol (? max 425 nm) partially overlaps the visible absorption bands of AuNPs. In this system, the peptide substrate (DEVD) of caspase 3 was linked to the AuNP surface by Au-S linkage. HRP was attached to the AuNP surface by means of a bridge formed by the streptavidin-biotin reaction. CRET occurred as a result of formation of AuNP-peptide-biotin-streptavidin-HRP complexes. The CL of luminol was significantly reduced, because of the quenching effect of AuNPs. The quenched CL was recovered after cleavage of DEVD by caspase 3, an enzyme involved in the apoptotic process. Experimental conditions were systematically investigated. Under the optimum conditions the increase of the CL signal was linearly dependent on caspase 3 concentration within the concentration range 25 pmol L(-1) to 800 pmol L(-1) and the detection limit of caspase 3 was as low as 20 pmol L(-1), one order of magnitude lower than for FRET sensors based on graphene oxides. Our method was successfully used to detect drug-induced apoptosis of cells. This approach is expected to be extended to other assays, i.e., using other enzymes, analytes, CL substances, and even other nanoparticles (e.g., quantum dots and graphene). PMID:24481623

Huang, Xiangyi; Liang, Yiran; Ruan, Lingao; Ren, Jicun

2014-09-01

95

Influence of the storage time and the method of stimulation on whole blood chemiluminescence.  

PubMed

The ultra-weak light, chemiluminescence (CL), of stimulated leukocytes is a well-known phenomenon. Parameters of this CL are modified by many factors including laboratory procedures. The order of stimulation and enhancement (two possibilities) and two concentrations of luminol create four types of procedure, which were accomplished in five sample storage 'time points'. We received the strongest signals of CL using higher concentrations of luminol (and DMSO), but only when stimulation (FMLP) was used before enhancement (luminol); luminol used before FMLP strongly inhibited CL. For lower luminol concentration (and DMSO), the order of stimulation and enhancement was of no importance. There were comparable but weaker signals of CL in this case. We received stronger signals with storage time for all procedures. It may be dependent on the priming of phagocytes by releasing cell factors. Stimulation (FMLP) before enhancement (luminol) eliminates the inhibitory effect of DMSO on CL. PMID:12444591

Podraza, Wojciech; Gonet, Boles?aw; Kordek, Agnieszka

2002-01-01

96

Determination of bisphenol A in water via inhibition of silver nanoparticles-enhanced chemiluminescence  

Microsoft Academic Search

Sensitive detection of trace bisphenol A (BPA) in water samples has been accomplished via inhibition of luminol chemiluminescence (CL) by BPA on the silver nanoparticles (AgNPs)-enhanced luminol–KMnO4 CL system for the first time. Under the optimized experimental conditions, the CL intensity was found to be proportional to the concentration of BPA ranging from 1.0×10?8 to 5.0×10?5gL?1. The detection limit (3?)

Xiaolan Chen; Can Wang; Xinmei Tan; Jianxiu Wang

2011-01-01

97

Chemiluminescence determination of trimetazidine via inducing the aggregation of gold nanoparticles  

NASA Astrophysics Data System (ADS)

A simple, rapid and sensitive chemiluminescence (CL) method combined with flow injection analysis was developed for the determination of trimetazidine. Trimetazidine was found to significantly increase the CL signal arising from N-bromosuccinimide-luminol reaction in the presence of gold nanoparticles. The enhanced CL intensity was proportional to trimetazidine concentration in the range of 0.01-5.0 ?g/mL, with a limit of detection (3sb) of 6.7 ng/mL. The relative standard deviation was 2.8% for 11 repetitive measurements of 0.1 ?g/mL trimetazidine solution. The practicality of the method was evaluated by determining trimetazidine in pharmaceutical formulations and in spiked human serum samples. Moreover, the possible CL reaction mechanism was also discussed.

Li, Jiao; Quan, Jie; Du, Jianxiu; Liu, Mei

2013-10-01

98

Molecular beam chemiluminescence studies of the NO + O/sub 3/ reaction and modeling of global NO/sub 2/ distribution  

SciTech Connect

The results of a crossed molecular beam study of the chemiluminescent reaction NO + 0/sub 3/ ..-->.. NO/sub 2/ + 0/sub 2/ are discussed. The chemiluminescence as a function of collision energy and an excitation function were obtained using a translationally cooled supersonic NO beam. An investigation into the role of the internal energy states using an effusive NO beam and a supersonic O/sub 3/ beam has been presented. The results show that chemiluminescence enhancement occurs when high and low temperature NO experiments are compared. The role that other energy modes may have is discussed. The observed enhancement is consistent with the concept that the chemiluminescence cross section increases with NO molecular rotation for low J states. The second part discusses the role of NO/sub 2/ in preserving a global ozone balance. NO/sub 2/ vertical profiles based on Noxon's (1979) column measurements were derived. The method of instantaneous rates was used to calculate the rate of ozone production and destruction by O/sub x/ and NO/sub x/ on a grid that covered the entire globe. The results were presented as a function of altitude and latitude in contour plots.

Kowalczyk, M.

1980-11-01

99

The Chemiluminescence Homepage  

NSDL National Science Digital Library

Dr. Thomas Chasteen at Sam Houston State University created this compilation of sites and texts related to chemiluminescence, a process where "energy in the form of light is released from matter because of a chemical reaction." The site contains Quick Time animations, descriptions of related phenomena, links to related sites, and two bibliographies, one targeting advanced readers and the other targeting K-12 readers.

100

A two-channel microfluidic sensor that uses anodic electrogenerated chemiluminescence as a photonic reporter of cathodic redox reactions.  

PubMed

This paper describes a new approach for sensing electrochemically active substrates in microfluidic systems. This two-electrode sensor relies on electrochemical detection at one electrode and electrogenerated chemiluminescent (ECL) reporting at the other. Each microfabricated indium tin oxide electrode is located in a separate microfluidic channel, but the channels are connected downstream of the electrodes to maintain a complete electrical circuit. Because of laminar flow, there is no bulk mixing of the fluids in the detecting and reporting channels. This approach allows the ECL reaction to be physically and chemically decoupled from the sensing channel of the device, which greatly expands the number of analytes that can be detected. However, because the cathode and anode are connected, electron-transfer processes occurring at the sensing electrode are electrically coupled to the ECL reaction. Charge balance permits the ECL light output to be quantitatively correlated to electrochemical reductions at the cathode. The system is used to detect Fe(CN)6(3-), Ru(NH3)6(3+), and benzyl viologen and report their presence via Ru(bpy)3(2+) (bpy = bipyridine) luminescence. Each different redox target initiates ECL at a unique potential bias related to its standard redox potential. The influence of the concentrations of Ru(bpy)3(2+) and the target analytes is discussed. PMID:12553767

Zhan, Wei; Alvarez, Julio; Crooks, Richard M

2003-01-15

101

Study of the enhancement of a new chemiluminescence reaction and its application to determination of beta-lactam antibiotics.  

PubMed

An enhanced thiosemicarbazide(TSC)-H2O2 chemiluminescence (CL) system was established and proposed as a new analytical method for determination of beta-lactam antibiotics, ampicillin sodium and amoxicillin at microgram levels. The method is based on the inhibition of CL emission accompanying oxidation of TSC by H2O2 in alkaline medium. The effect of anionic, cationic, and non-ionic surfactants on the CL emission of the system was studied. Both N-cetyl-N,N,N-trimethylammonium bromide (CTMAB) and Triton X-100, unlike sodium dodecyl sulfate (SDS), reinforced the CL intensity and were efficient to approximately the same level. The effect of the presence of eight non-aqueous solvents on the CL system was also investigated. Upon addition of both of the non-ionic surfactant, Triton X-100, and the non-aqueous solvent, N,N-dimethyl formamide (DMF), the intensity of the CL reaction was increased 100-fold. This method allows the measurement of 25-545 microg amoxicillin, and 35-350 microg ampicillin sodium. The detection limits are 8 microg for amoxicillin and 9 microg for ampicillin sodium. The relative standard deviations of six replicate measurements of 200 microg amoxicillin and 200 microg ampicillin sodium were 1.9 and 2.1%, respectively. The effect of foreign species on the determination of amoxicillin and ampicillin sodium was also examined. The proposed method was successfully applied to the determination of ampicillin sodium and amoxicillin in some pharmaceutical dosage forms. PMID:18785613

Sorouraddin, M H; Iranifam, M; Imani-Nabiyyi, A

2009-01-01

102

How the morphology of biochips roughness increases surface-enhanced chemiluminescence  

NASA Astrophysics Data System (ADS)

Biochips of Au particle arrays were fabricated using nanosphere lithography to investigate the influence of gold roughness upon chemiluminescence induced by peroxidase adsorbed at surface. The corrugation of gold induces a strong enhancement of the chemiluminescence of luminol brought at its vicinity. This letter shows that this enhancement is increased by an order of magnitude when the corrugation is regular and possesses an average curvature radius of around 15 nm (for ordered particles arrays compared to films with random roughness).

Shen, Hong; Lu, Guowei; Ou, Meigui; Marquette, Christophe A.; Ledoux, Gilles; Roux, Stéphane; Tillement, Olivier; Perriat, Pascal; Cheng, Bolin; Chen, Zhenghao

2007-05-01

103

Multilayers enzyme-coated carbon nanotubes as biolabel for ultrasensitive chemiluminescence immunoassay of cancer biomarker  

Microsoft Academic Search

A novel and ultrasensitive chemiluminescence immunoassay (CLIA) method based on multiple enzyme layers assembled multiwall carbon nanotubes (MWCNTs) as signal amplification labels was developed by employing luminol–H2O2-HRP-bromophenol blue (BPB) enhanced chemiluminescence (CL) system for the detection of a cancer biomarker in human serum samples, as exemplified by the measurement of alpha-fetoprotein (AFP) as a model protein. In this study, horseradish

Sai Bi; Hong Zhou; Shusheng Zhang

2009-01-01

104

Metal-Enhanced Chemiluminescence: Advanced Chemiluminescence Concepts for the 21st Century  

PubMed Central

Chemiluminescent based detection is entrenched throughout the Biosciences today, such as in blotting, analyte and protein quantification and detection. While the biological applications of chemiluminescence are forever growing, the underlying principles of using a probe, an oxidizer and a catalyst (biological, organic or inorganic) have remained mostly unchanged for decades. Subsequently, chemiluminescence based detection is fundamentally limited by the classical photochemical properties of reaction yield, quantum yield, etc. However, for the last 5 years, a new technology has emerged which looks set to fundamentally change the way we both think about and use chemiluminescence today. Metal surface plasmons can amplify chemiluminescence signatures, while low-power microwaves can complete reactions within seconds. In addition, thin metal films, can convert spatially isotopic chemiluminescence into directional emission. In this timely forward looking tutorial review, we survey what could well be the next-generation chemiluminescent based technologies. PMID:19690736

Aslan, Kadir; Geddes, Chris D.

2009-01-01

105

Chemiluminescent solid lipid nanoparticles (SLN) and interations with intact skin  

NASA Astrophysics Data System (ADS)

We report the synthesis and characterization of a novel nanoparticle formulation designed for skin penetration for the purpose of skin imaging. Solid lipid nanoparticles (SLNs), a drug delivery vehicle, were used as the matrix for targeted delivery of peroxide-sensitive chemiluminescent compounds to the epidermis. Luminol and oxalate were chosen as the chemiluminescent test systems, and a formulation was determined based upon non-toxic components, lotion-like properties, and longevity/visibility of a chemiluminescent signal. The luminescence lifetime was extended in the lipid formulation in comparison to the chemiluminescent system in solution. When applied to porcine skin, our formulation remained detectable relative to negative and positive controls. Initial MTT toxicity testing using HepG2 cells have indicated that this formulation is relatively non-toxic. This formulation could be used to image native peroxides present in tissue that may be indicative of skin disease.

Breidenich, Jennifer; Patrone, Julia; Kelly, Lisa; Benkoski, Jason; Le, Huong; Sample, Jennifer

2009-08-01

106

High-sensitivity chemiluminescence detection of cytokines using an antibody-immobilized CMOS image sensor  

NASA Astrophysics Data System (ADS)

In this study, we used a Complementary Metal Oxide Semiconductor (CMOS) image sensor with immobilizing antibodies on its surface to detect human cytokines, which are activators that mediate intercellular communication including expression and control of immune responses. The CMOS image sensor has many advantages over the Charge Couple Device, including lower power consumption, operation voltage, and cost. The photodiode, a unit pixel component in the CMOS image sensor, receives light from the detection area and generates digital image data. About a million pixels are embedded, and size of each pixel is 3 x 3 ?m. The chemiluminescence reaction produces light from the chemical reaction of luminol and hydrogen peroxide. To detect cytokines, antibodies were immobilized on the surface of the CMOS image sensor, and a sandwich immunoassay using an HRP-labeled antibody was performed. An HRP-catalyzed chemiluminescence reaction was measured by each pixel of the CMOS image sensor. Pixels with stronger signals indicated higher cytokine concentrations; thus, we were able to measure human interleukin-5 (IL-5) at femtomolar concentrations.

Hong, Dong-Gu; Joung, Hyou-Arm; Kim, Sang-Hyo; Kim, Min-Gon

2013-05-01

107

Rate Determination of the CO2* Chemiluminescence Reaction CO + O + M = CO2* + M  

E-print Network

were used to evaluate the kinetics of CO2*, in particular, the main CO2* formation reaction, CO + O + M CO2* + M (R1). Based on collision theory, the quenching chemistry of CO2* was determined for eleven common collision partners. The final mechanism...

Kopp, Madeleine Marissa, 1987-

2012-10-15

108

Organo-modified layered double hydroxide-catalyzed Fenton-like ultra-weak chemiluminescence for specific sensing of vitamin B?? in egg yolks.  

PubMed

In general, the chemiluminescence (CL) sensing of vitamin B12 is achieved by determining Co(II) liberated from acidified vitamin B12 by a luminol system. However, the luminol system for sensing vitamin B12 has poor selectivity due to serious interference from other metal ions. In this study, as a novel CL amplifier of the Co(II)+H2O2+OH(-) ultra-weak CL reaction (Fenton-like system), dodecylbenzene sulfonate (DBS)-layered double hydroxides (LDHs) have been applied to the specific determination of vitamin B12 by liberating Co(II). The CL intensity increased with increasing the concentration of vitamin B12 in a wide range from 1.0 ng mL(-1) to 5 ?g mL(-1) with a detection limit of 0.57 ng mL(-1) (S/N=3). The proposed method has been successfully applied to determine vitamin B12 in egg yolk with simple procedures, shorter time and higher selectivity. Recoveries from spiked real samples were 96-103%. The results of the proposed method for sensing vitamin B12 in real samples were agreed with those obtained by the standard inductively coupled plasma mass spectrometry (ICP-MS) method. To the best of our knowledge, this is the first report on the CL sensing of vitamin B12 with high selectivity in the absence of luminol. PMID:25127574

Zhang, Lijuan; Rong, Wanqi; Lu, Chao; Zhao, Lixia

2014-11-01

109

Chemiluminescence from Dissolved Oxygen  

Microsoft Academic Search

RED chemiluminescence corresponding to about 40 kcal\\/mol., and attributable to the forbidden transition 1Sigma+g --> 3Sigma-g of the oxygen molecule, has been observed in three recent investigations1-3, but no explanation of the effect has been presented. These involve organic hydroperoxides or oxidations with hydrogenperoxide and also the reaction of hydrogen peroxide with HClO. In contrast with this, decompositions of hydrogen

E. J. Bowen

1964-01-01

110

Homogeneous assay of target molecules based on chemiluminescence resonance energy transfer (CRET) using DNAzyme-linked aptamers.  

PubMed

We have designed a single-stranded DNAzyme-aptamer sensor for homogeneous target molecular detection based on chemiluminescence resonance energy transfer (CRET). The structure of the engineered single-stranded DNA (ssDNA) includes the horseradish peroxidase (HRP)-like DNAzyme, optimum-length linker (10-mer-length DNA), and target-specific aptamer sequences. A quencher dye was modified at the 3' end of the aptamer sequence. The incorporation of hemin into the G-quadruplex structure of DNAzyme yields an active HRP-like activity that catalyzes luminol to generate a chemiluminescence (CL) signal. In the presence of target molecules, such as ochratoxin A (OTA), adenosine triphosphate (ATP), or thrombin, the aptamer sequence was folded due to the formation of the aptamer/analyte complex, which induced the quencher dye close to the DNAzyme structure. Consequently, the CRET occurred between a DNAzyme-catalyzed chemiluminescence reaction and the quencher dye. Our results showed that CRET-based DNAzyme-aptamer biosensing enabled specific OTA analysis with a limit of detection of 0.27ng/mL. The CRET platform needs no external light source and avoids autofluorescence and photobleaching, and target molecules can be detected specifically and sensitively in a homogeneous manner. PMID:24658027

Mun, Hyoyoung; Jo, Eun-Jung; Li, Taihua; Joung, Hyou-Arm; Hong, Dong-Gu; Shim, Won-Bo; Jung, Cheulhee; Kim, Min-Gon

2014-08-15

111

How surface-enhanced chemiluminescence depends on the distance from a corrugated metal film  

NASA Astrophysics Data System (ADS)

Peroxidase labeled streptavidin was immobilized onto the surface of bulk and clusterlike metal films at a distance controlled by a peptide chain with a length between 1.3 and 7.8nm. Luminol chemiluminescence which occurred at peroxidase vicinity depends on the metal nanostructure. When peroxidase is attached on a bulklike film, chemiluminescence increases monotonously with the distance because of a decrease of the light emission quenching by metal. When peroxidase is attached on a clusterlike film, chemiluminescence undergoes a complex variation with the metal/catalyst distance evidencing a competition between the already mentioned quenching process and a nanostructure-induced catalysis enhancement.

Lu, Guowei; Shen, Hong; Cheng, Bolin; Chen, Zhenghao; Marquette, Christophe A.; Blum, Loic J.; Tillement, Olivier; Roux, Stéphane; Ledoux, Gilles; Ou, Meigui; Perriat, Pascal

2006-11-01

112

Simple chamber facilitates chemiluminescent detection of bacteria  

NASA Technical Reports Server (NTRS)

Test chamber enables rapid estimation of bacteria in a test sample through the reaction of luminol and an oxidant with the cytochrome C portion of certain species of bacteria. Intensity of the light emitted in the reaction is a function of the specific bacteria in the test sample.

Marts, E. C.; Wilkins, J. R.

1970-01-01

113

Ultrasensitive detection of transcription factors using transcription-mediated isothermally exponential amplification-induced chemiluminescence.  

PubMed

Transcription factors (TFs) are important cellular components that modulate gene expression, and the malregulation of transcription will lead to a variety of diseases such as cancer and developmental syndromes. However, the conventional methods for transcription factor assay are generally cumbersome and costly with low sensitivity. Here, we develop a label-free strategy for ultrasensitive detection of transcription factors using a cascade signal amplification of RNA transcription, dual isothermally exponential amplification reaction (EXPAR), and G-quadruplex DNAzyme-driven chemiluminescence. Briefly, the specific binding of TF with the detecting probe prevents the cleavage of the detecting probe by exonuclease and subsequently facilitates the conversion of TF signal to abundant RNA triggers in the presence of T7 RNA polymerase. The obtained RNA triggers can initiate the strand displacement amplification to yield abundant DNAzymes and DNA triggers, and the released DNA triggers can further initiate the next rounds of EXPAR reaction. The synergistic operation of dual EXPAR reaction can produce large amounts of DNAzymes, which subsequently catalyze the oxidation of luminol by H2O2 to yield an enhanced chemiluminescence signal with the assistance of cofactor hemin. Conversely, in the absence of target TF, the naked detecting probes will be completely digested by exonucleases, leading to neither the transcription-mediated EXPAR nor the DNAzyme-driven chemiluminescence signal. This method has a low detection limit of as low as 6.03 × 10(-15) M and a broad dynamic range from 10 fM to 1 nM and can even measure the NF-?B p50 of crude cell nuclear extracts. Moreover, this method can be used to measure a variety of DNA-binding proteins by simply substituting the target-specific binding sequence in the detecting probes. PMID:24865817

Ma, Fei; Yang, Yong; Zhang, Chun-Yang

2014-06-17

114

Interactions of methemoglobin and green hemoprotein in chemiluminescent gels.  

PubMed

Peroxidation of luminol (5-amino-2,3-dihydrophthalazine-1,4-dione) catalyzed by human green hemoprotein (GHP) and bovine methemoglobin (MetHb) in gels composed of cross-linked bovine serum albumin was examined. The chemiluminescence (CL) was followed with a low-light intensity video camera and imaging system attached to a circularly polarized microwave guide (2450 MHz) for heating the samples from 24 degrees C to 37 degrees C. Steady-state CL was maintained in the gels for 10 min. The intensity of the CL varied with temperature. When combined with MetHb in the same gel, GHP inhibited CL of MetHb from 83.6% to 98.2% over a fiftyfold concentration range of GHP. Although MetHb/GHP combination gels were inhibited, they generated a 6.12-fold CL per degree C change compared to a 0.19-fold per degree C change for MetHb gels and a 0.31-fold per degree C change for GHP gels. The data suggest an interaction between GHP and MetHb that inhibits the CL reaction, is not interfered with by large amounts of albumin, and is partially reversed by heating. PMID:2332192

Kiel, J L; McQueen, C; Erwin, D N

1990-01-01

115

Following glucose oxidase activity by chemiluminescence and chemiluminescence resonance energy transfer (CRET) processes involving enzyme-DNAzyme conjugates.  

PubMed

A hybrid consisting of glucose oxidase-functionalized with hemin/G-quadruplex units is used for the chemiluminescence detection of glucose. The glucose oxidase-mediated oxidation of glucose yields gluconic acid and H(2)O(2). The latter in the presence of luminol acts as substrate for the hemin/G-quadruplex-catalyzed generation of chemiluminescence. The glucose oxidase/hemin G-quadruplex hybrid was immobilized on CdSe/ZnS quantum dots (QDs). The light generated by the hybrid, in the presence of glucose, activated a chemiluminescence resonance energy transfer process to the QDs, resulting in the luminescence of the QDs. The intensities of the luminescence of the QDs at different concentrations of glucose provided an optical means to detect glucose. PMID:22346648

Niazov, Angelica; Freeman, Ronit; Girsh, Julia; Willner, Itamar

2011-01-01

116

Controllable copper deficiency in Cu2-xSe nanocrystals with tunable localized surface plasmon resonance and enhanced chemiluminescence.  

PubMed

Copper chalcogenide nanocrystals (CuCNCs) as a type of semiconductor that can also act as efficient catalysts are rarely reported. Herein, we study water-soluble size-controlled Cu(2-x)Se nanocrystals (NCs), which are copper deficient and could be prepared by a redox reaction with the assistance of surfactants. We found them to have strong near-infrared localized surface plasmon resonance (LSPR) properties originating from the holes in the valence band, and also catalytic activity of more than a 500-fold enhancement of chemiluminescence (CL) in a luminol-H2O2 system. Investigations into the mechanisms behind these results showed that the high concentration of free carriers in Cu(2-x)Se NCs, which are derived from their high copper deficiencies that make Cu(2-x)Se NCs both good electron donors and acceptors with high ionic mobility, could greatly enhance the catalytic ability of Cu(2-x)Se NCs to facilitate electron-transfer processes and the decomposition of H2O2 into OH? and O2(?-), which are the commonly accepted key intermediates in luminol CL enhancement. Thus, it can be concluded that controllable copper deficiencies that are correlated with their near-infrared LSPR are critically responsible for the effective catalysis of Cu(2-x)Se NCs in the enhanced CL. PMID:25065365

Lie, Shao Qing; Wang, Dong Mei; Gao, Ming Xuan; Huang, Cheng Zhi

2014-09-01

117

Exonuclease III-assisted cascade signal amplification strategy for label-free and ultrasensitive chemiluminescence detection of DNA.  

PubMed

Detection of ultralow concentrations of specific nucleic acid sequences is a central challenge in the early diagnosis of genetic diseases and biodefense applications. Herein, we report a simple and homogeneous chemiluminescence (CL) method for ultrasensitive DNA detection. It is based on the exonuclease III (Exo III)-assisted cascade signal amplification and the catalytic effect of G-quadruplex-hemin DNAzyme on the luminol-H2O2 CL system. A quadruplex-forming DNA probe hybridizes a hairpin DNA probe to construct a duplex DNA probe as recognition element. Upon sensing of target DNA, the recognition of target DNA and the duplex DNA probe triggers the Exo III cleavage process, accompanied by releasing target DNA and generating a new secondary target DNA fragment. The released target DNA and the secondary target DNA are recycled. Simultaneously, numerous quadruplex-forming sequences are liberated and bind hemin to yield G-quadruplex-hemin DNAzyme, which subsequently catalyze the luminol-H2O2 reaction to produce strong CL emission. This method exhibited a high sensitivity toward target DNA with a detection limit of 8 fM, which was about 100 times lower than that of the reported DNAzyme-based colorimetric system for DNA detection with Exo III-assisted cascade signal amplification. This method provides a simple, isothermal, and low-cost approach for sensitive detection of DNA and holds a great potential for early diagnosis in gene-related diseases. PMID:25140892

Gao, Yuan; Li, Baoxin

2014-09-01

118

A highly sensitive chemiluminescent metalloimmunoassay for H1N1 influenza virus detection based on a silver nanoparticle label.  

PubMed

A versatile, ultrasensitive chemiluminescent metalloimmunoassay method for detection of H1N1 influenza virus was designed by using silver nanoparticles as an anti-H1N1 labeling tag to strongly amplify the CL signal of luminol. PMID:23999899

Li, Yanxia; Hong, Mei; Qiu, Bin; Lin, Zhenyu; Cai, Zongwei; Chen, Yiting; Chen, Guonan

2013-11-21

119

Fiber-Optic Chemiluminescent Biosensors for Monitoring Aqueous Alcohols and Other Water Quality Parameters  

NASA Technical Reports Server (NTRS)

A "reagentless" chemiluminescent biosensor and method for the determination of hydrogen peroxide, ethanol and D-glucose in water is disclosed. An aqueous stream is basified by passing it through a solid phase base bed. Luminol is then dissolved in the basified effluent at a controlled rate. Oxidation of the luminol is catalyzed by the target chemical to produce emitted light. The intensity of the emitted light is detected as a measure of the target chemical concentration in the aqueous stream. The emitted light can be transmitted by a fiber optic bundle to a remote location from the aqueous stream for a remote reading of the target chemical concentration.

Verostko, Charles E. (Inventor); Atwater, James E. (Inventor); Akse, James R. (Inventor); DeHart, Jeffrey L. (Inventor); Wheeler, Richard R. (Inventor)

1998-01-01

120

A novel chemiluminescence from the reaction of singlet oxygen with ?-diketonates of europium(iii), neodymium(iii) and ytterbium(iii).  

PubMed

Decomposition of 1,4-dimethylnaphthalene endoperoxide, which is the source of singlet oxygen, in the presence of ?-diketonates of europium(iii), neodymium(iii) and ytterbium(iii) is accompanied by bright chemiluminescence (CL) in visible and near infra-red spectral region due to characteristic emission from the lanthanides at ?max = 615 and 710 nm ((5)D0?(7)F2 and (5)D0?(7)F4 transitions of Eu(3+)), 900 nm ((4)F3/2?(4)I9/2 transition of Nd(3+)) and 1000 nm ((2)F5/2?(2)F7/2 transition of Yb(3+)). Singlet oxygen is the key intermediate responsible for the observed CL, which is presumably generated by the reaction of (1)O2 with ligands of the complexes. The CL phenomenon discovered herein paves the way towards the development of lanthanide-based CL probe for (1)O2. PMID:25358493

Kazakov, Dmitri V; Safarov, Farit E

2014-12-12

121

Online Detection of Reactive Oxygen Species in Ultraviolet (UV)-Irradiated Nano-TiO2 Suspensions by Continuous Flow Chemiluminescence.  

PubMed

Reactive oxygen species (ROS) play very important roles in the photocatalytic reactions of semiconductors. Using a continuous flow chemiluminescence (CFCL) system, we developed three methods for the selective, sensitive, and online detection of O2(• -), •OH, and H2O2 generated during ultraviolet (UV) irradiation of nano-TiO2 suspensions. TiO2 nanoparticles were irradiated in a photoreactor and pumped continuously into a detection cell. To detect O2(• -), luminol was mixed with TiO2 before it entered the detection cell. For the detection of short-lived •OH, phthalhydrazide was added into the photoreactor to capture •OH, and then mixed with H2O2/K5Cu(HIO6)2 to produce chemiluminescence (CL). To detect H2O2, an irradiated TiO2 suspension was kept in darkness for 30 min, and then mixed with luminol/K3Fe(CN)6 to produce CL. The selectivity of each method for a particular ROS was verified by using specific ROS scavengers. For a given ROS, a comparison between CL and conventional method showed good agreement for a series of TiO2 concentrations. The sensitivity of CL method was approximately 3-, 1200-, and 5-fold higher than the conventional method for O2(• -), •OH, and H2O2, respectively. To demonstrate the utility of the methods, ROS in three different types of TiO2 suspensions was detected by CFCL. It was found that photodegradation efficiency of Rhodamine B correlated the best (R(2) > 0.95) with the amount of photogenerated •OH, implying that •OH was the major oxidant in Rhodamine B photodegradation reaction. CFCL may provide a convenient tool for the studies on the reaction kinetics of ROS-participated decomposition of environmental contaminants. PMID:25275618

Wang, Dabin; Zhao, Lixia; Guo, Liang-Hong; Zhang, Hui

2014-11-01

122

Chemiluminescence induced by phagocytosis of Escherichia coli by polymorphonuclear leucocytes.  

PubMed

Chemiluminescence emitted by phagocytosing human polymorphonuclear leucocytes stimulated by Escherichia coli was measured using a liquid scintillation counter equipped with a multichannel analyser. In the presence of the amplifying agent luminol, light emission can be divided into two channels, one of which ('high energy') appears to correlate directly with phagocytic activity of the PMNL, and the other ('low energy') with the background luminol dioxygenation by the cells. Measuring in the 'high energy' window also eliminates the normal 'out of coincidence' background. The method is applicable to measuring opsonizing capacity of different sera, and responds to PMNL number, age, composition of assay medium and the integrity of the stimulating bacteria. Other bacterial strains produce a similar response, as does the artificial stimulator zymosan. Low temperature and anaerobiosis, which inhibit phagocytic killing, also suppress light emission. PMID:6389762

Fazeli, A; Richards, L

1984-09-01

123

Reduction of biological effluents in purge and trap micro reaction vessels and detection of endothelium-derived nitric oxide (edno) by chemiluminescence.  

PubMed

Various analytical approaches have been used to measure endothelium-derived nitric oxide (NO). We have detected NO in perfusates with a sample size as low as 2 ml after acidification with 4 N HC1 to pH less than 2 at 25 degrees C by using a Nitric Oxide Analyser (Sievers, Colorado). This procedure had the advantage that the detectable level of NO was enhanced by the self-decomposition of HNO2 when the PH less than pKa of NHO2 (pKa = 3.15) and also the reaction temperature of 25 degrees C substantially increased the half-line of NO. Palmer, et al., measured NO released by cultured porcine endothelial cells by chemiluminescence after passing cell effluents continuously at a rate of 5 ml/min into 75 ml of 1% sodium iodide in glacial acetic acid. The larger volumes involved in this method for continuous refluxing, made it less desirable for the detection of endothelium-derived nitric oxide. Feelisch et al. utilized the activation of soluble guanylate cyclase, as well as, the quantitative oxidation of oxyhemoglobin to methemoglobin in aqueous solutions by NO as a means of measuring nitric oxide. We describe here a modification of our earlier micromethod which now enables us to detect NO after complete reduction with glacial acetic acid and sodium iodide. A comparison of the two procedures indicate that while freshly prepared NO standard solutions gave identical chemiluminescence response with and without reduction, effluents from bovine intrapulmonary artery under basal conditions gave substantially higher values upon reduction. PMID:1942075

Menon, N K; Patricza, J; Binder, T; Bing, R J

1991-04-01

124

Ethanolic crude extract and flavonoids isolated from Alternanthera maritima: neutrophil chemiluminescence inhibition and free radical scavenging activity.  

PubMed

Extracts from Alternanthera maritima are used in Brazilian folk medicine for the treatment of infectious and inflammatory diseases. Bioassay-guided fractionation of A. maritima aerial parts yielded an ethanolic crude extract, its butanolic fraction and seven isolated flavonoids (two aglycones, two O-glycosides and three C-glycosides) with antioxidative activity. The ability of these samples to scavenge enzymatically generated free radicals (luminol-horseradish peroxidase-H2O2 reaction) and inhibit reactive oxygen species (ROS) production by opsonized zymosan-stimulated human neutrophils (PMNLs) was evaluated by chemiluminescence methods. In both assays, the butanolic fraction was significantly more active than the ethanolic crude extract, the flavonoid aglycones had high inhibitory activities and the C-glycosylated flavonoids had no significant effect even at the highest concentration tested (50 micromol/L). However, the O-glycosylated flavonoids inhibitory effects on chemiluminescence were strongly dependent on the chemical structure and assay type (cellular or cell-free system). Under the conditions tested, active samples were not toxic to human PMNLs. PMID:17708437

Souza, Joel G; Tomei, Rafael R; Kanashiro, Alexandre; Kabeya, Luciana M; Azzolini, Ana Elisa C S; Dias, Diones A; Salvador, Marcos J; Lucisano-Valim, Yara M

2007-01-01

125

Chemiluminescence assay of mucosal reactive oxygen metabolites in inflammatory bowel disease.  

PubMed

Previous studies suggesting increased reactive oxygen metabolite (ROM) production in inflammatory bowel disease have been restricted to peripheral blood and isolated intestinal phagocytes. In the current study, chemiluminescence and the effect of various scavengers, enzymes, and enzyme inhibitors were used to show that ROMs account for the increased production of oxidants by colorectal mucosal biopsy specimens in inflammatory bowel disease. Luminol-amplified chemiluminescence was increased in active ulcerative colitis [macroscopic grade 1: 25 photons.mg-1.min.10(-3) (median), 8-47 (95% confidence intervals), n = 40; grade 2: 89, 65-156, n = 30; grade 3: 247, 133-562, n = 13] and Crohn's disease [mild: 9, 3-84, n = 6; severe: 105, 25-789 (range), n = 5] compared with normal-looking mucosa (ulcerative colitis: 0.8, 0.4-1.4, n = 22, P less than 0.01; Crohn's disease: 0.8, 0.1-2, n = 6, P less than 0.05) and controls (0.6, 0.04-1.4, n = 52, P less than 0.01). In ulcerative colitis, luminol chemiluminescence correlated with microscopic inflammation (Spearman's p = 0.74, P = 0.0001) and was decreased by sodium azide (-89%, P less than 0.05), taurine (-31%, P less than 0.05), catalase (-23%, P less than 0.05), and dimethyl sulfoxide (-29%, P less than 0.05). Superoxide dismutase and oxypurinol decreased lucigenin chemiluminescence in ulcerative colitis by -63% (P less than 0.05) and -27% (P less than 0.05), respectively. Luminol chemiluminescence correlated with lucigenin chemiluminescence (Spearman's rho = 0.72, P = 0.003). These results suggest that neutrophil-derived oxidants (superoxide, hydrogen peroxide, hydroxyl radical, and hypochlorite) are generated in colorectal mucosa in active inflammatory bowel disease and support the hypothesis that production of such metabolites by neutrophils is of major pathogenetic importance. PMID:1319369

Simmonds, N J; Allen, R E; Stevens, T R; Van Someren, R N; Blake, D R; Rampton, D S

1992-07-01

126

Binding study of lysozyme with Al(III) using chemiluminescence analysis.  

PubMed

The binding behavior of lysozyme with Al(III) is described using luminol as a luminescence probe by flow injection-chemiluminescence (FI-CL) analysis. It was found that the CL intensity of the luminol-lysozyme reaction could be markedly enhanced by Al(III), and the increase in CL intensity was linear with the Al(III) concentration over the range 0.3-30.0? pg ?mL(-1) , with a detection limit of 0.1?pg ?mL(-1) (3?). Based on the interaction model of lysozyme with Al(III), lg[(I?-?I0 )/(2I0 ?-?I)]?=?lgK?+?nlg[M], the binding constant K?=?6.84?×?10(6) ?L?mol(-1) and the number of binding sites (n)?=?0.76. The relative standard deviations were 3.2, 2.4 and 2.0% for 10.0, 20.0 and 30.0 ?pg ?mL(-1) Al(III) (n?=?7), respectively. This new method was successfully applied to continuous, quantitative monitoring of picogram level Al(III) in human saliva following oral intake of compound aluminum hydroxide tablets. It was found that Al(III) in saliva reached a maximum of 101.2? ng ?mL(-1) at 3.0?h. The absorption rate constant ka , elimination rate constant k and half-life time t1/2 of Al(III) were 1.378? h(-1) , 0.264? h(-1) and 2.624 ?h, respectively. PMID:24127408

Liu, Jiangman; Luo, Kai; Song, Zhenghua

2014-09-01

127

Microfabricated Renewable Beads-Trapping/Releasing Flow Cell for Rapid Antigen-Antibody Reaction in Chemiluminescent Immunoassay  

SciTech Connect

A filter pillar-array microstructure was coupled with a pneumatic micro-valve to fabricate a reusable miniaturized beads-trapping/releasing flow cell, in which trapping and releasing beads can be conveniently realized by switching the micro-valve. This miniaturized device was suitable to construct automatic fluidic system for “renewable surface analysis”. The renewable surface strategy based on pneumatic micro-valve enabled capture of beads in beads chamber prior to each assay, and release of the used beads after the assay. Chemiluminescent competitive immunoassay of 3,5,6-trichloropyridinol (TCP) was performed as a model to demonstrate the application potential of this reusable miniaturized flow cell. The whole fluidic assay process including beads trapping, immuno-binding, beads washing, beads releasing and signal collection could be completed in 10 min. Immunoassay of TCP using this miniaturized device showed a linear range of 0.20-70 ng/mL with a limit of detection of 0.080 ng/mL. The device had been successfully used for detection of TCP spiked in rat serum with average recovery of 97%. This investigation provides a rapid, sensitive, reusable, low-cost and automatic miniaturized device for solid-phase biochemical analysis for various purposes.

Fu, Zhifeng; Shao, Guocheng; Wang, Jun; Lu, Donglai; Wang, Wanjun; Lin, Yuehe

2011-04-01

128

Chemiluminescence determination of sulphadiazine in drugs by flow injection analysis using the peroxyoxalate reaction in micellar medium.  

PubMed

Peroxyoxalate chemiluminescence (PO-CL) is an indirect type of CL which allows the detection of native fluorophores or compounds derivatized with fluorescent labels. We propose a flow injection analysis (FIA) configuration based on the use of a two-injection valve system for the introduction of both PO and derivatized analyte solutions in the flow system, avoiding the problems arising from the use of organic solvents, such as acetonitrile, as no special tubes nor special pumps are required. Furthermore, the use of micellar media (sodium dodecyl sulphate, SDS) as a carrier and the addition of tetrahydrofurane (THF) in the PO solutions increase both the solubility and stability of POs, avoiding their rapid degradation in water. The proposed CL-FIA system has been applied to the determination of sulphadiazine (a sulphonamide mainly used in the treatment of urinary tract infections for human and veterinary use) using bis[2,4,6-trichlorophenyl]oxalate (TCPO) as CL precursor, H2O2 as oxidant, imidazole as a catalyst and fluorescamine as the fluorescent derivatizing agent. The optimization of variables was carried out by means of experimental designs and the method showed a LOQ of 379 microg l(-1) (calibration range 126-2000 microg l(-1)). It has been satisfactorily applied to the quantification of sulphadiazine in pills for human use and ampoules for veterinary use. PMID:18031965

Lattanzio, Giuseppe; García-Campaña, Ana M; Soto-Chinchilla, Jorge J; Gámiz-Gracia, Laura; Girotti, Steffano

2008-01-22

129

Chemiluminescence of the reaction system Ce(IV)-non-steroidal anti-inflammatory drugs containing europium(III) ions and its application to the determination of naproxen in pharmaceutical preparations and urine.  

PubMed

The chemiluminescence (CL) of oxidation of non-steroidal anti-inflammatory drugs (NSAIDs) by Ce(IV) ions, was recorded in the presence and absence europium(III) ions, in solution of pH ~ 4 of solution. Kinetic curves and CL emission spectra of the all studied systems were discussed. CL of measurable intensity was observed in the Ce(IV)-NP-Eu(III) reaction system only in acidic solutions. The CL spectrum rcegistered for this system shows emission bands, typical of Eu(III) ions, with maximum at ? ~ 600 nm. The chemiluminescent method, based on Eu(III) emission in reaction system of NP-Ce(IV)-Eu(III) in acid solution was therefore used for the determination of naproxen in mixture of non-steroidal anti-inflammatory drugs. PMID:21750890

Kaczmarek, Ma?gorzata

2011-11-01

130

Plant tissue-based chemiluminescence flow biosensor for determination of unbound dopamine in rabbit blood with on-line microdialysis sampling  

Microsoft Academic Search

A novel plant tissue-based chemiluminescence (CL) biosensor for dopamine combined with flow injection analysis is presented in this paper. The potato roots act as molecular recognition elements. Dopamine is oxidized by oxygen under the catalysis of polyphenol oxidase in the tissue column to produce hydrogen peroxide, which can react with luminol in the presence of peroxidase of potato tissue to

Baoxin Li; Zhujun Zhang; Yan Jin

2002-01-01

131

Rapid, sensitive and on-line measurement of chemical oxygen demand by novel optical method based on UV photolysis and chemiluminescence  

Microsoft Academic Search

A novel on-line method based on the combination of UV photolysis and chemiluminescence detection was established and experimentally validated for the determination of chemical oxygen demand (COD). A quantitative amount of free radicals can be produced by analytes in the UV irradiation process. By utilizing the phenomenon that luminol can be oxidized by the free radicals to produce luminescence, COD

Yingying Su; Xiaohong Li; He Chen; Yi Lv; Xiandeng Hou

2007-01-01

132

Blood and Milk Neutrophil Chemiluminescence and Viability in Primiparous and Pluriparous Dairy Cows During Late Pregnancy, Around Parturition and Early Lactation  

Microsoft Academic Search

Extensive studies have shown the polymorphonu- clear leukocytes (PMN) dysfunction inextricably links to parturition. To investigate the effect of parity on PMN function, phorbol 12-myristate 13-acetate (PMA) stimulated luminol-amplified chemiluminescence (CL) and viability of blood and milk PMN were investigated in primiparous and pluriparous dairy cows during peri- parturient period. The CL kinetics of blood and milk PMN and hematological

Jalil Mehrzad; Luc Duchateau; Satu Pyörälä; Christian Burvenich

2002-01-01

133

Introducing novel amorphous carbon nanoparticles as energy acceptors into a chemiluminescence resonance energy transfer immunoassay system.  

PubMed

A novel chemiluminescence resonance energy transfer (CRET) system for competitive immunoassay of biomolecules was developed by using novel amorphous carbon nanoparticles (CNPs) prepared from candle soot as energy acceptors. The CNPs were firstly prepared to bind with the antigen (Ag) for obtaining the nanocomposite CNP-Ag, and this obtained CNP-Ag was then reacted with the horseradish peroxidase-labeled antibody (HRP-Ab) to assemble the CRET system. The luminol catalyzed by HRP serving as the energy donor for CNPs triggered the CRET phenomenon between luminol and CNPs, which led to the chemiluminescence signal decrease. Due to the competitive immunoreaction of the target antigen and the CNP-Ag, a part of the CNP-Ag was replaced from the HRP-Ab, and then resulted in a weaker interaction between luminol and CNPs. Thus the competitive immunoreaction led to a higher chemiluminescence emission. This CNP-based CRET system was successfully applied to detect the human IgG as a model analyte, and a linear range of 10-200 ng mL(-1) and a detection limit of 1.9 ng mL(-1) (S/N = 3) were obtained. The results for real sample analysis demonstrated its application potential in some important areas such as clinical diagnosis. PMID:23979821

Wang, Zhenxing; Gao, Hongfei; Fu, Zhifeng

2013-11-21

134

Ultrasensitive determination of DNA sequences by flow injection chemiluminescence using silver ions as labels.  

PubMed

We presented a new strategy for ultrasensitive detection of DNA sequences based on the novel detection probe which was labeled with Ag(+) using metallothionein (MT) as a bridge. The assay relied on a sandwich-type DNA hybridization in which the DNA targets were first hybridized to the captured oligonucleotide probes immobilized on Fe3O4@Au composite magnetic nanoparticles (MNPs), and then the Ag(+)-modified detection probes were used to monitor the presence of the specific DNA targets. After being anchored on the hybrids, Ag(+) was released down through acidic treatment and sensitively determined by a coupling flow injection-chemiluminescent reaction system (Ag(+)-Mn(2+)-K2S2O8-H3PO4-luminol) (FI-CL). The experiment results showed that the CL intensities increased linearly with the concentrations of DNA targets in the range from 10 to 500pmolL(-1) with a detection limit of 3.3pmolL(-1). The high sensitivity in this work may be ascribed to the high molar ratio of Ag(+)-MT, the sensitive determination of Ag(+) by the coupling FI-CL reaction system and the perfect magnetic separation based on Fe3O4@Au composite MNPs. Moreover, the proposed strategy exhibited excellent selectivity against the mismatched DNA sequences and could be applied to real samples analysis. PMID:25263118

Zheng, Lichun; Liu, Xiuhui; Zhou, Min; Ma, Yongjun; Wu, Guofan; Lu, Xiaoquan

2014-10-27

135

Chemiluminescent determination of esterases in monocytes.  

PubMed

Esterase from monocytes promotes the hydrolysis of 2-methyl-1-propenylbenzoate (MPB) yielding 2-methyl-1-propenol, which is oxidized by horseradish peroxidase/H2O2 producing triplet acetone. The chemiluminescence of this reaction can be enhanced by the addition of 9,10-dibromoanthracene-2-sulphonate. The non-specific esterase present in monocytes is responsible for MPB hydrolysis, since (a) the chemiluminescence of the reaction was inhibited by fluoride, and (b) cells that do not contain a significant amount of non-specific esterases, e.g. lymphocytes and neutrophils, did not trigger light emission. The analytical application of this reaction is considered. PMID:9743443

da Fonseca, L M; Yavo, B; Catalani, L H; Falcão, R P; Brunetti, I L; Campa, A

1998-01-01

136

Balancing single- and multi-reference correlation in the chemiluminescent reaction of dioxetanone using the anti-Hermitian contracted Schro?dinger equation.  

PubMed

Direct computation of energies and two-electron reduced density matrices (2-RDMs) from the anti-Hermitian contracted Schro?dinger equation (ACSE) [D. A. Mazziotti, Phys. Rev. Lett. 97, 143002 (2006)], it is shown, recovers both single- and multi-reference electron correlation in the chemiluminescent reaction of dioxetanone especially in the vicinity of the conical intersection where strong correlation is important. Dioxetanone, the light-producing moiety of firefly luciferin, efficiently converts chemical energy into light by accessing its excited-state surface via a conical intersection. Our previous active-space 2-RDM study of dioxetanone [L. Greenman and D. A. Mazziotti, J. Chem. Phys. 133, 164110 (2010)] concluded that correlating 16 electrons in 13 (active) orbitals is required for realistic surfaces without correlating the remaining (inactive) orbitals. In this paper we pursue two complementary goals: (i) to correlate the inactive orbitals in 2-RDMs along dioxetanone's reaction coordinate and compare these results with those from multireference second-order perturbation theory (MRPT2) and (ii) to assess the size of the active space-the number of correlated electrons and orbitals-required by both MRPT2 and ACSE for accurate energies and surfaces. While MRPT2 recovers very different amounts of correlation with (4,4) and (16,13) active spaces, the ACSE obtains a similar amount of correlation energy with either active space. Nevertheless, subtle differences in excitation energies near the conical intersection suggest that the (16,13) active space is necessary to determine both energetic details and properties. Strong electron correlation is further assessed through several RDM-based metrics including (i) total and relative energies, (ii) the von Neumann entropy based on the 1-electron RDM, as well as the (iii) infinity and (iv) squared Frobenius norms based on the cumulant 2-RDM. PMID:21548676

Greenman, Loren; Mazziotti, David A

2011-05-01

137

Chemiluminescent chemical sensors for inorganic and organic vapors  

SciTech Connect

Chemiluminescent, chemical sensors for inorganic and organic vapors are being investigated via the immobilization of 3-aminophthalhydrazide (luminol) within hydrogels and polymeric, sorbent coatings. The films are supported behind a teflon membrane and positioned in front of a photomultiplier tube, permitting the sensitive detection of numerous toxic vapors. Some selectivity has been tailored into these devices by careful selection of the polymer type, pH and metal catalyst incorporated within the film. The incorporation of luminol and Fe(3) within a polyvinylalcohol hydrogel gave a film with superior sensitivity toward NO{sub 2} (detection limit of 0.46 ppb and a response time on the order of seconds). The use of the hydrogel matrix helped eliminate humidity problems associated with other polymeric films. Other chemiluminescent thin films prepared have demonstrated the detection of ppb levels of SO{sub 2}(g) and hydrazine, N{sub 2}H{sub 4}(g). Recently, the authors have begun investigating the incorporation of a heated Pt filament into the inlet line as a pre-oxidative step prior to passage of the gas stream across the teflon membrane. This has permitted the sensitive detection of ppm levels of CCl{sub 4}(g), CHCl{sub 3}(g) and CH{sub 2}Cl{sub 2}(g).

Collins, G.E.; Rose-Pehrsson, S.L. [Naval Research Lab., Washington, DC (United States). Chemistry Division

1995-12-31

138

Aqueous chemiluminescent systems  

NASA Technical Reports Server (NTRS)

This invention relates to novel water-soluble esters of oxalic acid, and to compositions that are useful for generating chemiluminescent emission by reacting said esters of oxalic acid with hydrogen peroxide in the presence of water and a fluorescent compound, and to a process for generating chemiluminescent emission by using said compositions.

Mohan, Arthur Gaudens (Inventor)

1977-01-01

139

Evaluation of the antioxidant activity of different flavonoids by the chemiluminescence method.  

PubMed

The objective of the present investigation was to study the antioxidant action of different flavonoids (quercetin, glabridin, red clover, and Isoflavin Beta, an isoflavones mixture) in order to determine if they could be added to a topical formulation used to treat damage caused by free radicals. Samples of 10 microL of the test compounds at different concentrations were mixed with 0.1 M phosphate buffer, pH 7.4, and a luminol solution was added to yield a final concentration of 0.113 mM. Hydrogen peroxide was then added at a final concentration of 0.05 mM. The reaction was started by introducing the horseradish peroxidase enzyme at a final concentration of 0.2 IU/mL, in a final volume of 1.0 mL. Chemiluminescence was measured for 10 minutes at room temperature, and dimethylsulfoxide (DMSO) was used as a control. All samples showed marked inhibition of oxidative stress, with a concentration-dependent action for quercetin and Isoflavin Beta. The highest inhibition was observed with glabridin and the dry red clover extract. All flavonoids proved to be adequate for addition to topical formulations because of their high antioxidant activity. PMID:12866943

Georgetti, Sandra R; Casagrande, Rúbia; Di Mambro, Valéria M; Azzolini, Ana E C S; Fonseca, Maria J V

2003-01-01

140

Superoxide production and chemiluminescence induced in differentiated HL-60 cells by the chemoattractant formyl-methionyl-leucyl-phenylalanine.  

PubMed

Superoxide production and chemiluminescence induced in differentiated HL-60 cells by the chemoattractant formylmethionyl-leucyl-phenylalanine: In order to study the generation of oxidative metabolites in relation to cell differentiation, dimethyl sulfoxide (DMSO) and retinoic acid (RA) differentiated HL-60 cells were stimulated with the chemotactic peptide formylmethionyl-leucyl-phenylalanine (FMLP). The oxidative response was measured as luminol-dependent chemiluminescence, lucigenin-dependent chemiluminescence, and cytochrome c reduction. Cells grown in the presence of DMSO or RA progressively expressed morphological changes, and when the mature cells were exposed to FMLP the cells produced oxidative metabolites. Quantitatively the HL-60 cells grown in the presence of DMSO gave rise to the most pronounced response. No correlation was obtained between superoxide production, luminol-chemiluminescence and lucigenin-dependent chemiluminescence, indicating that different aspects of the oxidative response are elucidated by the three different methods. Furthermore, the experiments show that DMSO and RA-induced differentiation of HL-60 cells leads to granulocyte-like cells with different abilities to produce oxidative metabolites, possibly due to differences in receptor function. PMID:3021838

Dahlgren, C; Andersson, T; Stendahl, O

1986-01-01

141

A validated silver-nanoparticle-enhanced chemiluminescence method for the determination of citalopram in pharmaceutical preparations and human plasma.  

PubMed

A simple and sensitive chemiluminescence (CL) method was developed for the determination of citalopram in pharmaceutical preparations and human plasma. The method is based on the enhancement of the weak CL signal of the luminol-H2 O2 system. It was found that the CL signal arising from the reaction between alkaline luminol and H2 O2 was greatly increased by the addition of silver nanoparticles in the presence of citalopram. Prepared silver nanoparticles (AgNPs) were characterized by UV-visible spectroscopy and transmission electron microscopy (TEM). Various experimental parameters affecting CL intensity were studied and optimized for the determination of citalopram. Under optimized experimental conditions, CL intensity was found to be proportional to the concentration of citalopram in the range 40-2500?ng/mL, with a correlation coefficient of 0.9997. The limit of detection (LOD) and limit of quantification (LOQ) of the devised method were 3.78 and 12.62?ng/mL, respectively. Furthermore, the developed method was found to have excellent reproducibility with a relative standard deviation (RSD) of 3.65% (n?=?7). Potential interference by common excipients was also studied. The method was validated statistically using recovery studies and was successfully applied to the determination of citalopram in the pure form, in pharmaceutical preparations and in spiked human plasma samples. Percentage recoveries were found to range from 97.71 to 101.99% for the pure form, from 97.84 to 102.78% for pharmaceutical preparations and from 95.65 to 100.35% for spiked human plasma. PMID:23754499

Khan, Muhammad Naeem; Jan, Muhammad Rasul; Shah, Jasmin; Lee, Sang Hak

2014-05-01

142

Tested Demonstrations. A Chemiluminescence Demonstration - Oxalyl Chloride Oxidation.  

ERIC Educational Resources Information Center

This inexpensive, effective chemiluminescence demonstration requires minimal preparation. It is based on the oxidation of oxalyl chloride by hydrogen peroxide in the presence of an appropriate fluorescent sensitizer. The reaction mechanism is not completely understood. (BB)

Gilber, George L., Ed.

1979-01-01

143

[Lucigenin-enhanced chemiluminescence of the animal tissues].  

PubMed

Lucigenin-enhanced chemiluminescence (LcCL) allows one to investigate the reactions of superoxide anion radical (*O2-) generated by mitochondria and is applied to study the superoxide production in enzymatic and membrane systems by isolated mitochondria and cells, and in whole organs. The application of lucigenin-enhanced chemiluminescence to estimate the respiration of human tissues involves the use of small tissue pieces, which can be obtained, for instance, by biopsia; however, no systematic investigations have been performed on these objects. In the present paper, a comparative study of lucigenin-enhanced chemiluminescence of tissues isolated from different organs of the rat was carried out to elucidate its dependence on the extent of tissue defragmentation, storage time, and access for oxygen. It was shown that the addition of lucigenin to a piece of tissue, a suspension of fine tissue fragments, and homogenates greatly enhanced chemiluminescence, and a whole piece of tissue possessed a much lesser (by 1-1.5 order of magnitude) intensity of chemiluminescence than homogenate or gruel. In the absence of stirring of the surrounding solution, the lucigenin-enhanced chemiluminescence of tissue quickly decreased, apparently due to a decrease in the level of oxygen in the tissue, as the result of its consumption. The chemiluminescence consisted of two components: a lucigenin-dependent and lucigenin-independent one (intrinsic chemiluminescence). Thus, the tissue was a source of lucigenin-enhanced chemiluminescence, and this luminescence was observed only at a sufficient access for oxygen. The lucigenin-independent component did not practically depend on oxygen and was determined by the components coming out of the tissue into the surrounding solution. Nitric oxide (NO) inhibited chemiluminescence as its concentration increased and did not affect considerably the rate of oxygen consumption by the tissue. The results obtained allow one to conclude that lucigenin can be used as a rather effective chemiluminescent probe for the production of superoxide radicals by tissue pieces. PMID:18225665

Matveeva, N S; Liubitski?, O B; Osipov, A N; Vladimirov, Iu A

2007-01-01

144

A Chemiluminescence Detector for Ozone Measurement.  

ERIC Educational Resources Information Center

An ozone detector was built and evaluated for its applicability in smog chamber studies. The detection method is based on reaction of ozone with ethylene and measurement of resultant chemiluminescence. In the first phase of evaluation, the detector's response to ozone was studied as a function of several instrument parameters, and optimum…

Carroll, H.; And Others

145

Chemiluminescent Detection of Diffusion  

NSDL National Science Digital Library

This activity engages students in observing the results of diffusion through a selectively permeable membrane, monitoring the concentration of solute in water, learning the simple test for starch, and quantitating the chemiluminescence by exposure to photographic paper.

Evelyn Bradshaw (Cleveland Heights High School)

1995-07-01

146

Chemi-luminescence measurements of hyperthermal Xe{sup +}/Xe{sup 2+}+ NH{sub 3} reactions  

SciTech Connect

Luminescence spectra are recorded for the reactions of Xe{sup +}+ NH{sub 3} and Xe{sup 2+}+ NH{sub 3} at energies ranging from 11.5 to 206 eV in the center-of-mass (E{sub cm}) frame. Intense features of the luminescence spectra are attributed to the NH (A {sup 3}{Pi}{sub i}-X {sup 3}{Sigma}{sup -}), hydrogen Balmer series, and Xe I emission observable for both primary ions. Evidence for charge transfer products is only found through Xe I emission for both primary ions and NH{sup +} emission for Xe{sup 2+} primary ions. For both primary ions, the absolute NH (A-X) cross section increases with collision energy before leveling off at a constant value, approximately 9 x 10{sup -18} cm{sup 2}, at about 50 eV while H-{alpha} emission increases linearly with collision energy. The nascent NH (A) populations derived from the spectral analysis are found to be independent of collision energy and have a constant rotational temperature of 4200 K.

Prince, Benjamin D.; Steiner, Colby P. [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland AFB, New Mexico 87117 (United States); Chiu, Yu-Hui [Busek Co. Inc, Natick, Massachusetts 01760 (United States)

2012-04-14

147

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

NASA Astrophysics Data System (ADS)

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.

He, Xili; Song, Zhenghua

2013-10-01

148

Inhibition of chemiluminescence by carvedilol in the cell-free system, whole human blood and blood cells.  

PubMed

Carvedilol inhibits luminol-enhanced chemiluminescence of reactive oxygen metabolites in vitro. In this study it was found that, in the cell-free system, carvedilol dose-dependently decreased chemiluminescence in the following ranking order of radicals: hydroxyl radical > hydrogen peroxide > superoxide radical. The inhibition of myeloperoxidase was significant with carvedilol concentrations of 10 and 100 micromol/l and manifested in the concentration-dependent shift of chemiluminescence peaks to the right. In whole blood, carvedilol in concentrations of 10 and 100 micromol/l significantly inhibited chemiluminescence induced by both receptor-bypassing stimuli (A23187, PMA) and receptor-operating stimuli (fMLP, OpZ). Carvedilol dose-dependently inhibited chemiluminescence of isolated human polymorphonuclear leucocytes in the ranking order of stimuli: A23187 > OpZ > fMLP. In the presence of blood platelets, carvedilol did not substantially change chemiluminescence induced by fMLP and OpZ, while it was much more effective on chemiluminescence stimulated with calcium ionophore A23187. This could be the result of the supportive effect of serotonin liberated from platelets by A23187. PMID:15859027

Nosál, R; Jancinová, V; Cíz, M; Drábiková, K; Lojek, A; Fábryová, V

2005-01-01

149

A homogeneous chemiluminescent immunoassay method.  

PubMed

A new homogeneous chemiluminescent immunoassay method featuring the use of specific binding members separately labeled with an acridan-based chemiluminescent compound and a peroxidase is reported. Formation of an immunocomplex brings the chemiluminescent compound and the peroxidase into close proximity. Without any separation steps, a chemiluminescent signal is generated upon addition of a trigger solution, and the intensity is directly correlated to the quantity of the analyte. PMID:23477541

Akhavan-Tafti, Hashem; Binger, Dean G; Blackwood, John J; Chen, Ying; Creager, Richard S; de Silva, Renuka; Eickholt, Robert A; Gaibor, Jose E; Handley, Richard S; Kapsner, Kenneth P; Lopac, Senja K; Mazelis, Michael E; McLernon, Terri L; Mendoza, James D; Odegaard, Bruce H; Reddy, Sarada G; Salvati, Michael; Schoenfelner, Barry A; Shapir, Nir; Shelly, Katherine R; Todtleben, Jeff C; Wang, Guoping; Xie, Wenhua

2013-03-20

150

Flow-injection chemiluminescence sensor for determination of isoniazid in urine sample based on molecularly imprinted polymer  

NASA Astrophysics Data System (ADS)

In this paper, molecularly imprinted polymer (MIP) of isoniazid is synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of isoniazid template molecules. A novel flow injection chemiluminescence sensor for isoniazid determination is developed by packing the isoniazid-MIP into the flow cell as recognition elements. Isoniazid could be selectively adsorbed by the MIPs and the adsorbed isoniazid was sensed by its great enhancing effect on the weak CL reaction between luminol and periodate which were mixed in the flow cell. The enhanced CL intensity is linear in the range 2 × 10 -9 to 2 × 10 -7 g/mL and the detection limit is 7 × 10 -10 g/mL (3 ?) isoniazid with a relative standard deviation 2.8% ( n = 9) for 8 × 10 -8 g/mL. The sensor is reversible and reusable. It has a great improvement in sensitivity and selectivity for CL analysis. As a result, the sensor has been successfully applied to determination of isoniazid in human urine. At the same time, the binding characteristic of the polymer to isoniazid was evaluated by batch method and the dynamic method, respectively.

Xiong, Yan; Zhou, Houjiang; Zhang, Zhujun; He, Deyong; He, Chao

2007-02-01

151

A cascade amplification strategy based on rolling circle amplification and hydroxylamine amplified gold nanoparticles enables chemiluminescence detection of adenosine triphosphate.  

PubMed

A highly sensitive and selective chemiluminescent (CL) biosensor for adenosine triphosphate (ATP) was developed by taking advantage of the ATP-dependent enzymatic reaction (ATP-DER), the powerful signal amplification capability of rolling circle amplification (RCA), and hydroxylamine-amplified gold nanoparticles (Au NPs). The strategy relies on the ability of ATP, a cofactor of T4 DNA ligase, to trigger the ligation-RCA reaction. In the presence of ATP, the T4 DNA ligase catalyzes the ligation reaction between the two ends of the padlock probe, producing a closed circular DNA template that initiates the RCA reaction with phi29 DNA polymerase and dNTP. Therein, many complementary copies of the circular template can be generated. The ATP-DER is eventually converted into a detectable CL signal after a series of processes, including gold probe hybridization, hydroxylamine amplification, and oxidative gold metal dissolution coupled with a simple and sensitive luminol CL reaction. The CL signal is directly proportional to the ATP level. The results showed that the detection limit of the assay is 100 pM of ATP, which compares favorably with those of other ATP detection techniques. In addition, by taking advantage of ATP-DER, the proposed CL sensing system exhibits extraordinary specificity towards ATP and could distinguish the target molecule ATP from its analogues. The proposed method provides a new and versatile platform for the design of novel DNA ligation reaction-based CL sensing systems for other cofactors. This novel ATP-DER based CL sensing system may find wide applications in clinical diagnosis as well as in environmental and biomedical fields. PMID:24899364

Wang, Ping; Zhang, Tonghuan; Yang, Taoyi; Jin, Nan; Zhao, Yanjun; Fan, Aiping

2014-08-01

152

Chemiluminescence-based liquid chromatographic determination of hydrochlorothiazide and captopril  

Microsoft Academic Search

Narrow-bore liquid chromatography has been coupled to chemiluminescence detection for the determination of hydrochlorothiazide and captopril as such and as a two-component mixture in tablet formulations. A narrow-bore C18 reversed-phase column using sodium octane sulphonate as ion-pairing reagent proved suitable for the purpose. Tiopronin was used as the internal standard. Chemiluminescence detection was carried out based on the reaction with

J Ouyang; W. R. G Baeyens; J Delanghe; G Van Der Weken; W Van Daele; D De Keukeleire; A. M Garc??a Campaña

1999-01-01

153

Chemiluminescence: Synthesis of Cyalume 3 Chemiluminescence: Synthesis of Cyalume and Making it Glow  

E-print Network

it Glow Intro Chemiluminescence is the process whereby light is produced by a chemical reaction Release and Glow Formation The chemistry that forms the color glow in a light stick is shown below. In this experiment we will make Cyalume, the chemical used in "light sticks." A light stick contains a solution

Jasperse, Craig P.

154

[The chemiluminescence of the polymorphonuclear leukocytes in food poisoning].  

PubMed

Luminol- and lucigenin-dependent chemiluminescence (CL) induced by zymosan, opsonized autoserum was used to study the oxygen-dependent bactericidal system of polymorphonuclear leukocytes (PNL) in patients with food toxico-infections, at different disease periods. Different modifications of CL were established to have analogous dynamics on days 1 and 2 of the disease and differences as to the period of convalescence. A correlation was revealed between the amplitude of CL and the intensity of the intoxication syndrome. The conclusion is made about the role played by granulocytes in the disease pathogenesis. The authors review potential mechanisms of participation of PNL free radicals in the pathophysiological shifts responsible for the development, course and outcome of food toxico-infections. PMID:2094985

Popov, P Iu; Rosly?, I M; Malov, V A; Pak, S G

1990-01-01

155

Electrophoresis-chemiluminescence detection of phenols catalyzed by hemin.  

PubMed

Based on the catalytic activity of hemin, an efficient biocatalyst, an indirect capillary electrophoresis-chemiluminescence (CE-CL) detection method for phenols using a hemin-luminol-hydrogen peroxide system was developed. Through a series of static injection experiments, hemin was found to perform best in a neutral solution rather than an acidic or alkaline medium. Although halide ions such as Br(-) and F(-) could further enhance the CL signal catalyzed by hemin, it is difficult to apply these conditions to this CE-CL detection system because of the self-polymerization of hemin, as it hinders the CE process. The addition of concentrated ammonium hydroxide to an aqueous/dimethyl sulfoxide solution of hemin-luminol afforded a stable CE-CL baseline. The indirect CE-CL detection of five phenols using this method gave the following limits of detections: 4.8 × 10(-8) mol/L (o-sec-butylphenol), 4.9 × 10(-8) mol/L (o-cresol), 5.4 × 10(-8) mol/L (m-cresol), 5.3 × 10(-8) mol/L (2,4-dichlorophenol) and 7.1 × 10(-8) mol/L (phenol). PMID:24115262

Shu, Lu; Zhu, Jinkun; Wang, Qingjiang; He, Pingang; Fang, Yuzhi

2014-09-01

156

Micromachined microfluidic chemiluminescent system for explosives detection  

NASA Astrophysics Data System (ADS)

Results will be reported from efforts to develop a self-contained micromachined microfluidic detection system for the presence of specific target analytes under the US Office of Naval Research Counter IED Basic Research Program. Our efforts include improving/optimizing a dedicated micromachined sensor array with integrated photodetectors and the synthesis of chemiluminescent receptors for nitramine residues. Our strategy for developing chemiluminescent synthetic receptors is to use quenched peroxyoxalate chemiluminescence; the presence of the target analyte would then trigger chemiluminescence. Preliminary results are encouraging as we have been able to measure large photo-currents from the reaction. We have also fabricated and demonstrated the feasibility of integrating photodiodes within an array of micromachined silicon pyramidal cavities. One particular advantage of such approach over a conventional planar photodiode would be its collection efficiency without the use of external optical components. Unlike the case of a normal photodetector coupled to a focused or collimated light source, the photodetector for such a purpose must couple to an emitting source that is approximately hemispherical; hence, using the full sidewalls of the bead's confining cavity as the detector allows the entire structure to act as its own integrating sphere. At the present time, our efforts are concentrating on improving the signal-to-noise ratio by reducing the leakage current by optimizing the fabrication sequence and the design.

Park, Yoon; Neikirk, Dean P.; Anslyn, Eric V.

2007-04-01

157

Sensitive chemiluminescence immunoassay for E. coli O157:H7 detection with signal dual-amplification using glucose oxidase and laccase.  

PubMed

A novel, sensitive chemiluminescence (CL) immunoassay for Escherichia coli O157:H7 detection with signal dual-amplification using glucose oxidase (GOx) and laccase was investigated. The method was based on the characterization of a luminol-H2O2-laccase reaction. Compared with the horseradish peroxidase-based biosensor, laccase exhibited high catalytic activity in strong alkaline medium, which was compatible with the luminol system. The capture antibody was immobilized onto the magnetic bead (MB) surfaces. The detection antibody was linked with GOx through biotin-avidin recognition. Accordingly, the bioconjugation of MB-caputure antibody- E. coli O157:H7-detection antibody-GOx catalyzed the substrate glucose, thereby generating H2O2. E. coli O157:H7 was then detected by measuring the CL intensity after H2O2 formation. Under optimal conditions, the calibration plot obtained for E. coli O157:H7 was approximately linear from 4.3 × 10(3) colony-forming unit (CFU) mL(-1) to 4.3 × 10(5) CFU mL(-1), and the total assay time was <2.0 h without any enrichment. The limit of detection for the assay was 1.2 × 10(3) CFU mL(-1) (3?), which was considerably lower than that of enzyme-linked immunosorbent assay method (1.0 × 10(5) CFU mL(-1)) (3?). A series of repeatability measurements of using 1.7 × 10(4) CFU mL(-1) E. coli O157:H7 exhibited reproducible results with a relative standard deviation (RSD) of 3.5% (n = 11). Moreover, the proposed method was successfully used to detect E. coli O157:H7 in synthetic samples (spring water, apple juice, and skim milk), which indicated its potential practical application. This protocol can be applied in various fields of study. PMID:24405233

Zhang, Yun; Tan, Chen; Fei, Ruihua; Liu, Xiaoxiao; Zhou, Yuan; Chen, Jing; Chen, Huanchun; Zhou, Rui; Hu, Yonggang

2014-01-21

158

Defective chemiluminescence response in differentiated HL60 cells due to impaired degranulation.  

PubMed

In the presence of dimethyl sulfoxide, the promyelocytic leukemic cell line, HL60, differentiates into apparently mature polymorphonuclear leukocytes. When correlating the superoxide production from HL60 cells with the number of phagocytozing and NBT-positive cells, no difference was observed in comparison with normal peripheral blood leukocytes. In contrast, the luminol-dependent chemiluminescence was greatly impaired in the differentiated HL60 cells. Analysis of degranulation, i.e., release of myeloperoxidase and N-acetyl-beta-glucosaminidase- and myeloperoxidase-mediated iodination by HL60 cells, suggested that the defective chemiluminescence response observed in HL60 cells may be due to impaired release of myeloperoxidase from azurophilic granulae. This may lead to impaired microbicidal activity in these cells. PMID:3008851

Stendahl, O; Andersson, T; Dahlgren, C; Magnusson, K E

1986-05-01

159

Label-free chemiluminescent aptasensor for platelet-derived growth factor detection based on exonuclease-assisted cascade autocatalytic recycling amplification.  

PubMed

Here an exonuclease III (Exo III)-assisted cascade autocatalytic recycling amplification (Exo-CARA) strategy is proposed for label-free chemiluminescent (CL) detection of platelet-derived growth factor BB (PDGF-BB) by taking advantage of both recognition property of aptamer and cleavage function of Exo III. Functionally, this system consists of a duplex DNA (aptamer-blocker hybrid), two kinds of hairpin structures (MB1 and MB2), and Exo III. Upon recognizing and binding with PDGF-BB, aptamer folds into a close configuration, which initiates the proposed Exo-CARA reaction (Recyclings I?II?III?II). Finally, numerous "caged" G-quadruplex sequences on DNAzyme1 and DNAzyme2 release that intercalate hemin to catalyze the oxidation of luminol by H2O2 to generate an amplified CL signal, achieving excellent specificity and high sensitivity with a detection limit of 6.8×10(-13) M PDGF-BB. The proposed strategy has the advantages of simple design, isothermal conditions, homogeneous reaction without separation and washing steps, effective-cost without the need of labeling, and high amplification efficiency, which might be a universal and promising protocol for the detection of a variety of biomolecules whose aptamers undergo similar conformational changes. PMID:25016251

Bi, Sai; Luo, Baoyu; Ye, Jiayan; Wang, Zonghua

2014-12-15

160

Sensitive competitive flow injection chemiluminescence immunoassay for IgG using gold nanoparticle as label  

NASA Astrophysics Data System (ADS)

A sensitive competitive flow injection chemiluminescence (CL-FIA) immunoassay for immunoglobulin G (IgG) was developed using gold nanoparticle as CL label. In the configuration, anti-IgG antibody was immobilized on a glass capillary column surface by 3-(aminopropyl)-triethoxysilane and glutaraldehyde to form immunoaffinity column. Analyte IgG and gold nanoparticle labeled IgG were passed through the immunoaffinity column mounted in a flow system and competed for the surface-confined anti-IgG antibody. CL emission was generated from the reaction between luminol and hydrogen peroxide in the presence of Au (III), generated from chemically oxidative dissolution of gold nanoparticle by an injection of 0.10 mol L -1 HCl-0.10 mol L -1 NaCl solution containing 0.10 mmol L -1 Br 2. The concentration of analyte IgG was inversely related to the amount of bound gold nanoparticle labeled IgG and the CL intensity was linear with the concentration of analyte IgG from 1.0 ng mL -1 to 40 ng mL -1 with a detection limit of 5.2 × 10 -10 g mL -1. The whole assay time including the injections and washing steps was only 30 min for one sample, which was competitive with CL immunoassays based on a gold nanoparticle label and magnetic separation. This work demonstrates that the CL immunoassay incorporation of nanoparticle label and flow injection is promising for clinical assay with sensitivity and high-speed.

Qi, Honglan; Shangguan, Li; Liang, Lin; Ling, Chen; Gao, Qiang; Zhang, Chengxiao

2011-11-01

161

Influence of antibiotics on formylmethionyl-leucyl-phenylalanine-induced leukocyte chemiluminescence.  

PubMed Central

The effect of three antimicrobial agents, penicillin G, ampicillin, and chloramphenicol, on luminol-enhanced chemiluminescence of polymorphonuclear leukocytes stimulated by the chemoattractant formylmethionyl-leucyl-phenylalanine was studied. An inhibitory effect of penicillin G and of ampicillin was demonstrated, whereas chloramphenicol gave rise to an enhancement of the chemiluminescence response from polymorphonuclear leukocytes. These effects could be due to interaction between the drugs and the polymorphonuclear leukocytes, but they could also be the result of interference with the generation of light without any effect on the cells. Therefore, the effects of the same antimicrobial agents on the chemiluminescence generated from a cell-free system consisting of myeloperoxidase and hydrogen peroxide were investigated in parallel. The results obtained in the cell-free system were almost identical to those obtained in the cell system; i.e., penicillin G and ampicillin caused an inhibition and chloramphenicol caused an enhancement of the light emission. These results indicate that observed effects induced by drugs in a chemiluminescence assay are not necessarily due to interaction between the drug and polymorphonuclear leukocytes but may be caused by interference with other components of the assay. In view of these findings, the conflicting data reported in the literature on the effects of antimicrobial agents on phagocyte function are discussed. PMID:3606075

Briheim, G; Dahlgren, C

1987-01-01

162

On the structure of luminol sodium salts  

NASA Astrophysics Data System (ADS)

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, ? = 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, ? = 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.

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

163

Determination of residual enrofloxacin in food samples by a sensitive method of chemiluminescence enzyme immunoassay.  

PubMed

A chemiluminescence enzyme immunoassay (CLEIA) based on the HRP-luminol-H?O? chemiluminescence system for highly sensitive detection of enrofloxacin (ENR) was proposed in this study. Key factors that affect the precision and accuracy for the determination of ENR residues were optimised. Under the optimal conditions, the proposed method showed an excellent performance. The linearity range for method developed for determination of ENR was 0.35-1.0 ng/mL with a correlation coefficient greater than 0.994. The limit of detection was 0.03 ng/mL and the relative standard deviations (RSDs) were less than 9.4% and 13.0% for intra-day and inter-day assays. The proposed method was satisfactorily applied to determine ENR in milk, eggs, and honey samples at three spiked levels (0.4, 0.7, and 1.0 ng/mL) and the recoveries ranged from 92.4% to 104.2% for milk, 93.8% to 103.2% for eggs and 94.1% to 105.0% for honey, respectively. Compared the results of CLEIA with those of ELISA and HPLC, the advantages of the CLEIA were further confirmed. Moreover, one 96-well microtiter plate coated with anti-ENR can be used to detect multiple samples at the same time, which indicated that the CLEIA using HRP-luminol-H?O? system was a sensitive, high throughput and real-time method for ENR residues analysis. PMID:24295678

Yu, Fei; Yu, Songcheng; Yu, Lanlan; Li, Yanqiang; Wu, Yongjun; Zhang, Hongquan; Qu, Lingbo; Harrington, Peter de B

2014-04-15

164

Chemiluminescence immunoassay for the rapid and sensitive detection of antibody against porcine parvovirus by using horseradish peroxidase/detection antibody-coated gold nanoparticles as nanoprobes.  

PubMed

A rapid, simple, facile, sensitive and enzyme-amplified chemiluminescence immunoassay (CLIA) method to detect antibodies against porcine parvovirus has been developed. Horseradish peroxidase (HRP) and the detection antibody were simultaneously co-immobilized on the surface of gold nanoparticles using the electrostatic method to form gold nanoparticle-based nanoprobes. This nanoprobe was employed in a sandwich-type CLIA, which enables CL signal readout from enzymatic catalysis and results in signal amplification. The presence of porcine parvovirus infection was determined in porcine parvovirus antibodies by measuring the CL intensity caused by the reaction of HRP-luminol with H2 O2 . Under optimal conditions, the obtained calibration plot for the standard positive serum was approximately linear within the dilution range of 1:80 to 1:5120. The limit of detection for the assay was 1:10,240 (S/N = 3), which is much lower than that typically achieved with an enzyme-linked immunosorbent assay (1:160; S/N = 3). A series of repeatability measurements using 1:320-fold diluted standard positive serum gave reproducible results with a relative standard deviation of 4.9% (n = 11). The ability of the immunosensor to analyze clinical samples was tested on porcine sera. The immunosensor had an efficiency of 90%, a sensitivity of 93.3%, and a specificity of 87.5% relative to the enzyme-linked immunosorbent assay results. PMID:23832716

Zhou, Yuan; Zhou, Tao; Zhou, Rui; Hu, Yonggang

2014-06-01

165

Simultaneous quantification of 5-hydroxyindoleacetic acid and 5-hydroxytryptamine by capillary electrophoresis with quantum dot and horseradish peroxidase enhanced chemiluminescence detection.  

PubMed

A capillary electrophoresis (CE) with chemiluminescence (CL) detection method was developed for the simultaneous quantification of 5-hydroxyindoleacetic acid (5-HIAA) and 5-hydroxytryptamine (5-HT). In this method, CdTe quantum dot (QD) and horseradish peroxidase (HRP) were used as enhancing reagents to co-catalyze the post-column CL reaction between luminol and hydrogen peroxide, achieving highly efficient CL emission. 5-HIAA and 5-HT inhibit the CL emission resulting to the formation of negative peaks in electropherogram. The degree of CL suppression is proportional to the concentration of 5-HT and 5-HIAA. The linear ranges for the determination of 5-HIAA and 5-HT were 2.5×10(-8)-2.5×10(-6) M and 2.5×10(-8)-5.0×10(-6) M with detection limits (signal/noise=3) of 7.0×10(-9) M and 6.0×10(-9) M, respectively. Intraday precision do not exceed 5.0%. The accuracy was confirmed by the recoveries ranged from 98% to 104%. The present method was successfully applied for the quantification of 5-HIAA and 5-HT in human urine. The concentrations of 5-HT and 5-HIAA in human urine were found to be in the range of 0.78-1.2 ?M and 3.2-5.1 ?M, respectively. PMID:25125395

Zhang, Liangliang; Zhao, Yunsha; Huang, Junming; Zhao, Shulin

2014-09-15

166

Determination of phenolic compounds and their antioxidant activity in Erigeron acris L. extracts and pharmaceutical formulation by flow injection analysis with inhibited chemiluminescent detection.  

PubMed

It was found that the chemiluminescence (CL) produced from the reaction of luminol with iodine in the alkaline medium was strongly inhibited by plant phenolic compounds. Based on this finding, a new flow injection CL method was developed for the determination of caffeic acid and 6'-caffeoylerigeroside. The latter compound was isolated for the first time from Erigeron acris L. herb. The method was simple, rapid and sensitive with a detection limit of 4 x 10(-3) ng mL(-1) (caffeic acid) and 0.18 ng mL(-1) (6'-caffeoylerigeroside), linear range of 0.1-1.5 ng mL(-1) (caffeic acid) and 1-200 ng mL(-1) (6'-caffeoylerigeroside), relative standard deviation of 3.3% for 10 measurements of 0.45 ng mL(-1) caffeic acid and 2.9% for 40 ng mL(-1) 6'-caffeoylerigeroside. This method was successfully applied to determine the content of phenolic compounds/antioxidant activity of E. acris L. extracts and phenolic acids content in pharmaceutical formulation. A possible mechanism of the inhibition of the proposed CL system was discussed. PMID:18597966

Nalewajko-Sieliwoniuk, Edyta; Nazaruk, Jolanta; Antypiuk, Ewelina; Koj?o, Anatol

2008-11-01

167

A novel flow-injection method for the determination of Pt(IV) in environmental samples based on chemiluminescence reaction of lucigenin and biosorption.  

PubMed

A new flow-injection chemiluminescence method (FI-CL) was developed for the determination of trace amounts of Pt(IV). The method is based on the quenching effect of the analyte on CL emission generated by lucigenin in alkaline solution. Application of a column filled with an algae Chlorella vulgaris immobilized on Cellex-T resin allowed to preconcentrate and separate the Pt(IV) ions from complex environmental samples, such as road dust. The developed method is simple and does not require sophisticated instrumentation. It is also characterized by a very low limit of detection (0.1ngmL(-1)), good sensitivity and precision (RSD<3%). The accuracy of the presented method was confirmed by analysis of a certified reference material of tunnel dust (BCR-723). The content of Pt in road dust samples collected in Bia?ystok (Poland) in 2009 determined by the evaluated method was 351.8+/-54.6ngg(-1) and was higher than in samples collected in years 2000 and 2003. PMID:20441963

Malejko, Julita; Godlewska-Zy?kiewicz, Beata; Koj?o, Anatol

2010-06-15

168

Fast determination of thiacloprid by photoinduced chemiluminescence.  

PubMed

A new and sensitive application of chemiluminescence detection has been developed for the determination of the pesticide thiacloprid in water. It was based on the on-line photoreaction of thiacloprid in a basic medium, with quinine acting as the sensitizer of the chemiluminescent response; cerium (IV) in sulfuric acid medium was used as the oxidant. High degrees of automation and reproducibility were achieved using a flow-injection analysis (FIA) manifold. The validation of the method was performed in terms of selectivity, linearity, limit of detection (LOD), precision, and accuracy. Liquid chromatography with ultraviolet (UV) detection was used as reference for mineral, tap, ground, and spring water samples. The proposed method is fast (with a throughput of 130 h(-1)), sensitive (LOD of 0.8 ng mL(-1) without preconcentration steps and of 0.08 ng mL(-1) with solid-phase extraction [SPE]), low cost, and possible to couple with separation methods for the simultaneous determination of other pesticides. The enhanced chemiluminescence intensity was linear with the thiacloprid concentration above the 2-80 and 80-800 ng mL(-1) ranges. A possible reaction mechanism is also discussed. PMID:25014719

Catalá-Icardo, Mónica; López-Paz, José Luis; Pérez-Plancha, Laura María

2014-06-01

169

Sensitive and selective chemiluminescence assay for hydrogen peroxide in exhaled breath condensate using nanoparticle-based catalysis  

NASA Astrophysics Data System (ADS)

The catalytic properties of cubiform Co3O4 nanoparticles, ?-Fe2O3 nanorods, and NiO nanoparticles were studied using both microarray method and FI-CL method. These nanoarticles exhibit high specific catalytic effects on the chemiluminescence (CL) reaction of the luminol-H2O2 system in alkaline solution compared with other common catalysts. A reaction mechanism is described. It provides new insights into the application of nanoparticle materials. The CL method based on the use of the Co3O4 nanoparticles is ultrasensitive and particularly selective. Therefore, it was applied to the analysis of H2O2 which can be determined in the concentration range from 1.0 nM to 1000 nM, with a detection limit of 0.3 nM. The relative standard deviation is 2.1% at 0.1 ?M of H2O2 (for n = 11). The method was successfully applied to the determination of trace quantities of H2O2 in exhaled breath condensate (EBC) where it is a mediator of oxidative stress and a promising biomarker for diagnosing. The assay requires a small sample and no incubation time, and has an analytical runtime of <1 min. It is timesaving and suitable for larger studies. The levels of H2O2 in EBC are found to be elevated in healthy subjects (average = 0.54 nM), rheum subjects (average = 0.24 nM), and feverish subjects (average = 0.16 nM). Our data suggested that the average H2O2 concentration of EBC from feverish subjects was significantly higher than healthy subjects and rheumatic subjects.

Li, Xiaohua; Zhang, Zhujun; Tao, Liang; Gao, Miao

2013-04-01

170

Modulatory effect of visible light on chemiluminescence of stimulated and nonstimulated blood leukocytes of carp (Cyprinus carpio, L)  

NASA Astrophysics Data System (ADS)

Irradiation of carp blood leukocytes with a non-laser visible light resulted in a significant inhibition of the spontaneous luminol-dependent chemiluminescence in the cells of a part of the fish. Those leukocytes that were sensitive to the visible light, showed a shorter time-to-peak than the non sensitive, following their stimulation with Ca ionophore. Because a shorter time-to-peak correlates with inflammation, it could be suggested that the visible light susceptible leukocyte reflect a pre-inflammatory state of their donors.

Belotsky, Sandro; Avtalion, Ramy R.; Friedmann, Harry; Lubart, Rachel

1998-12-01

171

Chemiluminescent detection of enzymatically produced hydrogen sulfide: substrate hydrogen bonding influences selectivity for H2S over biological thiols.  

PubMed

Hydrogen sulfide (H2S) is now recognized as an important biological regulator and signaling agent that is active in many physiological processes and diseases. Understanding the important roles of this emerging signaling molecule has remained challenging, in part due to the limited methods available for detecting endogenous H2S. Here we report two reaction-based ChemiLuminescent Sulfide Sensors, CLSS-1 and CLSS-2, with strong luminescence responses toward H2S (128- and 48-fold, respectively) and H2S detection limits (0.7 ± 0.3, 4.6 ± 2.0 ?M, respectively) compatible with biological H2S levels. CLSS-2 is highly selective for H2S over other reactive sulfur, nitrogen, and oxygen species (RSONS) including GSH, Cys, Hcy, S2O3(2–), NO2(–), HNO, ONOO(–), and NO. Despite its similar chemical structure, CLSS-1 displays lower selectivity toward amino acid-derived thiols than CLSS-2. The origin of this differential selectivity was investigated using both computational DFT studies and NMR experiments. Our results suggest a model in which amino acid binding to the hydrazide moiety of the luminol-derived probes provides differential access to the reactive azide in CLSS-1 and CLSS-2, thus eroding the selectivity of CLSS-1 for H2S over Cys and GSH. On the basis of its high selectivity for H2S, we used CLSS-2 to detect enzymatically produced H2S from isolated cystathionine ?-lyase (CSE) enzymes (p < 0.001) and also from C6 cells expressing CSE (p < 0.001). CLSS-2 can readily differentiate between H2S production in active CSE and CSE inhibited with ?-cyanoalanine (BCA) in both isolated CSE enzymes (p < 0.005) and in C6 cells (p < 0.005). In addition to providing a highly sensitive and selective reaction-based tool for chemiluminescent H2S detection and quantification, the insights into substrate–probe interactions controlling the selectivity for H2S over biologically relevant thiols may guide the design of other selective H2S detection scaffolds. PMID:24093945

Bailey, T Spencer; Pluth, Michael D

2013-11-01

172

CHEMILUMINESCENCE MEASUREMENT OF REACTIVITY WEIGHTED ETHYLENE-EQUIVALENT HYDROCARBONS  

EPA Science Inventory

A reactive hydrocarbon analyzer (RHA), based on the chemiluminescent reaction of hydrocarbons with oxygen atoms, is used to provide a rapid indication of reactivity weighted hydrocarbon mass in automobile exhaust. Samples are reported by their ethylene-equivalent concentration--t...

173

ZnO nanoparticles as an oxidase mimic-mediated flow-injection chemiluminescence system for sensitive determination of carvedilol.  

PubMed

A simple, rapid and sensitive method was developed using ZnO nanoparticle (ZnO-NP) amplified flow-injection chemiluminescence to detect carvedilol, a non-cardioselective ?-blocker. It has been found that carvedilol strongly inhibits the chemiluminescence of luminol-H2O2 catalyzed by ZnO-NPs. Under optimum conditions, a linear working range for carvedilol concentrations from 5 × 10(-8) to 1.0 × 10(-6) mol L(-1) (r > 0.9894, n = 8) was obtained with a detection limit of 3.25 × 10(-9) mol L(-1). The relative standard deviation for 8 repetitive determinations was less than 2.9% and recoveries of 99% and 102% were obtained. ZnO-NPs were synthesized using a green mechanochemical route. Transmission electron microscopy and x-ray diffraction were used to characterize ZnO-NPs. The method was successfully applied to detect carvedilol in pharmaceutical formulations. PMID:25159387

Biparva, Pourya; Abedirad, Seyed Mohammad; Kazemi, Sayed Yahya

2014-12-01

174

Phagocytic and chemiluminescent responses of mouse peritoneal macrophages to living and killed Salmonella typhimurium and other bacteria  

SciTech Connect

In the presence of luminol, resident as well as thioglycolate-induced and immunized macrophages emitted chemiluminescence more efficiently when the cells were exposed to living Salmonella typhimurium than when they were exposed to the same bacterium killed by ultraviolet light or heat. This phenomenon was observed whether or not the bacterium was opsonized. The different response to living and killed bacteria was also found with Escherichia coli, Pseudomonas aeruginosa, Proteus morganii, and Enterobacter aerogenes, but not with Shigella sonnei, Klebsiella pneumoniae, and Propionibacterium acnes. The results suggest that macrophages respond better to living, motile bacteria than to nonmotile or killed bacteria. The experimental results obtained with motility mutants of S. typhimurium, E. coli, and P. aeruginosa confirm that macrophages exposed to the motile bacteria emit chemiluminescence more efficiently and ingest the motile bacteria at a much faster rate than the nonmotile bacteria.

Tomita, T.; Blumenstock, E.; Kanegasaki, S.

1981-06-01

175

Oscillating chemiluminescence with thiosemicarbazide in a batch reactor.  

PubMed

Oscillating chemical reactions are complex systems involving a large number of chemical species. In oscillating chemical reactions, some species, usually reaction intermediates, exhibit fluctuations in their concentration. In this report, a novel slowly-damped oscillating chemiluminescence produced by the addition of thiosemicarbazide (TSC) to the oscillating system H2O2-KSCN-CuSO4-NaOH was investigated. Narrow and slightly asymmetric light pulses of 1.5 s half-width are emitted at 440 nm, with an oscillation period of 22-363 s, an induction period of 9-397 s and an emitted light time of 700-1500 s, depending on reagent concentrations. In this study the dependence of the induction period and the oscillation period on the reagent concentrations was investigated and both parameters were plotted with respect to reagent concentrations. Copper concentration showed a significant effect on the oscillation period. A possible mechanism for the oscillating chemiluminescence reaction is discussed. PMID:18452144

Sorouraddin, M H; Iranifam, M

2008-01-01

176

3D-printed and CNC milled flow-cells for chemiluminescence detection.  

PubMed

Herein we explore modern fabrication techniques for the development of chemiluminescence detection flow-cells with features not attainable using the traditional coiled tubing approach. This includes the first 3D-printed chemiluminescence flow-cells, and a milled flow-cell designed to split the analyte stream into two separate detection zones within the same polymer chip. The flow-cells are compared to conventional detection systems using flow injection analysis (FIA) and high performance liquid chromatography (HPLC), with the fast chemiluminescence reactions of an acidic potassium permanganate reagent with morphine and a series of adrenergic phenolic amines. PMID:24881540

Spilstead, Kara B; Learey, Jessica J; Doeven, Egan H; Barbante, Gregory J; Mohr, Stephan; Barnett, Neil W; Terry, Jessica M; Hall, Robynne M; Francis, Paul S

2014-08-01

177

Comparison of chemiluminescence methods for analysis of hydrogen peroxide and hydroxyl radicals  

NASA Astrophysics Data System (ADS)

Assessment of alpha radiolysis influence on the chemistry of geologically disposed spent fuel demands analytical methods for radiolytic product determination at trace levels. Several chemiluminescence methods for the detection of radiolytic oxidants hydrogen peroxide and hydroxyl radicals are tested. Two of hydrogen peroxide methods use luminol, catalyzed by either ?-peroxidase or hemin, one uses 10-methyl-9-(p-formylphenyl)-acridinium carboxylate trifluoromethanesulfonate and one potassium periodate. All recipes are tested as batch systems in basic conditions. For hydroxyl radical detection luminophores selected are 3-hydroxyphthalic hydrazide and rutin. Both methods are tested as batch systems. The results are compared and the applicability of the methods for near-field dissolution studies is discussed.

Pehrman, R.; Amme, M.; Cachoir, C.

2006-01-01

178

Developments and Applications of Electrogenerated Chemiluminescence Sensors Based on Micro- and Nanomaterials  

PubMed Central

A variety of recent developments and applications of electrogenerated chemiluminescence (ECL) for sensors are described. While tris(2,2?-bipyridyl)-ruthenium(II) and luminol have dominated and continue to pervade the field of ECL-based sensors, recent work has focused on use of these lumophores with micro- and nanomaterials. It has also extended to inherently luminescent nanomaterials, such as quantum dots. Sensor configurations including microelectrode arrays and microfluidics are reviewed and, with the recent trend toward increased use of nanomaterials, special attention has been given to sensors which include thin films, nanoparticles and nanotubes. Applications of ECL labels and examples of label-free sensing that incorporate nanomaterials are also discussed.

Hazelton, Sandra G.; Zheng, Xingwang; Zhao, Julia Xiaojun; Pierce, David T.

2008-01-01

179

Revealing interaction between sulfobutylether-?-cyclodextrin and reserpine by chemiluminescence and site-directed molecular docking.  

PubMed

The host-guest interaction between sulfobutylether-?-cyclodextrin (SBE-?-CD) and reserpine (RSP) is described using flow injection-chemiluminescence (FI-CL) and site-directed molecular docking methods. It was found that RSP could inhibit the CL intensity produced by a luminol/SBE-?-CD system. The decrease in CL intensity was logarithmic over an RSP concentration range of 0.03 to 700.0 nM, giving a regression equation of ?I?=?107.1lgCRES ?+?186.1 with a detection limit of 10 pM (3?). The CL assay was successfully applied in the determination of RSP in injection, saliva and urine samples with recoveries in the range 93.5-106.1%. Using the proposed CL model, the binding constant (KCD-R ) and the stoichiometric ratio of SBE-?-CD/RSP were calculated to be 7.4?×?10(6) ?M(-1) and 1 : 1, respectively. Using molecular docking, it was confirmed that luminol binds to the small cavity of SBE-?-CD with a nonpolar interaction, while RSP targeted the larger cavity of SBE-?-CD and formed a 1 : 1 complex with hydrogen bonds. The proposed new CL method has the potential to become a powerful tool for revealing the host-guest interaction between CDs and drugs, as well as monitoring drugs with high sensitivity. PMID:24127401

Xiong, Xunyu; Wu, Min; Zhao, Xinfeng; Song, Zhenghua

2014-09-01

180

Flow-injection chemiluminescence determination of gentamicin: optimization by central composite design.  

PubMed

A simple and sensitive flow-injection chemiluminescence (CL) method has been developed for the determination of gentamicin sulfate. The method is based on the inhibitory effect of gentamicin on the CL emission accompanying oxidation of luminol by H2 O2 in an alkaline medium in the presence of Cu(II) as a catalyst. Inhibition was caused by the formation of a strong complex between analyte and the catalyst. Experimental variables, including the concentrations of luminol (µmol/L), H2 O2 (mol/L), Cu(II) (mol/L) and NaOH (mol/L), were optimized using a central composite design. Under optimum conditions, the plot of CL intensity versus gentamicin concentration was found to have two linear ranges. One range was at low concentrations from 1.0 to 10.0?mg/L and the other was from 10.0 to 30.0?mg/L. Precision was calculated by analyzing samples containing 5.0?mg/L gentamicin (n?=?11) and the relative standard deviation (RSD) was 1.7%. Also, a high injection throughput of 120 samples/h was achieved. This method was successfully applied to the determination of gentamicin sulfate in pharmaceutical formulations and water samples. PMID:23744581

Iranifam, M; Hasanzadeh, A; Fathinia, M; Khataee, A R; Mousavi, S A

2014-05-01

181

Enhanced chemiluminescent detection scheme for trace vapor sensing in pneumatically-tuned hollow core photonic bandgap fibers  

E-print Network

We demonstrate an in-fiber gas phase chemical detection architecture in which a chemiluminescent (CL) reaction is spatially and spectrally matched to the core modes of hollow photonic bandgap (PBG) fibers in order to enhance ...

Stolyarov, Alexander Mark

182

Determination of ofloxacin using a chemiluminescence flow-injection method  

Microsoft Academic Search

A new chemiluminescence (CL) flow-injection method was proposed for the determination of ofloxacin in pharmaceuticals in the range 0.04?4?gml?1 with a detection limit of 0.016?gml?1 and a relative standard derivation (R.S.D.) of 2.2% at 0.4?gml?1 (n=10). The method is based on the CL reaction of cerium(IV) with sulphite sensitized by ofloxacin. The established procedure could be applied to the determination

Yi Rao; Yan Tong; Xinrong Zhang; Guoan Luo; Willy R. G Baeyens

2000-01-01

183

Investigation of singlet oxygen generation in Vit C-Cu2+ -LDL system by chemiluminescence method  

NASA Astrophysics Data System (ADS)

In this study, by chemiluminescence method using a Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7- dihydroimidazo[1,2-a]pyrazin-3-one (MCLA), as a selective and sensitive chemiluminescence probe, singlet oxygen (1O2) formation was observed in the vit C- LDL-Cu2+ reaction system. Another experimental evidence for the generation of 1O2 was the quenching effect of sodium azide (NaN3) on vit C-induced chemiluminescence in the reaction mixture of LDL- Cu2+-MCLA. Analysis based on the experimental results indicated the plausible reaction mechanism is that vit C converts Cu2+ to its reduced state and vit C becomes vit C radical itself, thereby stimulating the formation of peroxyl radicals, and bimolecular reaction of peroxyl radicals results in 1O2 production in the above systems.

Wang, Juan; Xing, Da; Tan, Shici; Tang, Yonghong; He, Yonghong

2002-04-01

184

Stimulation of chemiluminescence and resistance against aerogenic influenza virus infection by synthetic muramyl dipeptide combined with trehalose dimycolate.  

PubMed Central

The effect on respiratory burst of splenic cells from mice pretreated with oil-in-water emulsions of muramyl dipeptide (MDP), trehalose dimycolate (TDM), or the combination of MDP with TDM was studied by luminol-dependent chemiluminescence in response to stimulation by zymosan. Spleen cells from mice pretreated with TDM, but not those of mice treated with MDP, generated increased chemiluminescence. Spleen cells from animals pretreated with the combination of MDP and TDM exhibited markedly enhanced chemiluminescence activity. The effect of enhanced activity of preparations containing MDP combined with TDM was further examined in vivo by an aerosol infection of pretreated mice with a mouse-pathogenic influenza virus. Pretreatment with 6-O-acyl analogs and one ubiquinone derivative of MDP alone did not induce any resistance against influenza virus. Significant protection was conferred only when MDP and certain analogs were combined with TDM. The enhancement of nonspecific resistance to influenza virus infection was related to the chemical structure of the synthetic immunostimulant. A greater degree of protection was induced by the combination of TDM with the lipophilic derivatives like B 30-MDP and L-18 MDP. PMID:6317568

Masihi, K N; Brehmer, W; Azuma, I; Lange, W; Muller, S

1984-01-01

185

Enhanced competitive chemiluminescent enzyme immunoassay for the trace detection of insecticide triazophos.  

PubMed

A direct competitive chemiluminescent enzyme immunoassay (CLEIA) for triazophos was developed, which was based on the anti-THHe IgG monoclonal antibody and a heterogeneous enzyme tracer (THHu-HRP). Several components of chemiluminescent enhanced solution (CES) were optimized. The results showed that 1 mM of p-iodo-phenol, 0.625 mM of luminol, and 4 mM of H(2)O(2) had the best performance. Based on the study of CES, the influence of several factors (assay buffer, blocking substance, and solvent) on the immunoassay was investigated. The sensitivity for detection, IC(50) value was 0.87 ng/mL at a practical working concentration range between 0.04 ng/mL and 5 ng/mL and the limit of detection for triazophos was 0.063 ng/mL. The average recovery of triazophos added to lettuce, carrot, apple, water, and soil were 78.71%, 67.52%, 118.3%, 117.2%, and 122.0%, respectively. Finally, comparison between the methods of CLEIA and high-performance liquid chromatography-tandem mass spectrum (HPLC-MS/MS) was performed. The results obtained from CLEIA were in agreement with those of HPLC-MS/MS. PMID:22490114

Jin, Maojun; Shao, Hua; Jin, Fen; Gui, Wenjun; Shi, Xiaomei; Wang, Jing; Zhu, Guonian

2012-05-01

186

A magnetic particles-based chemiluminescence enzyme immunoassay for rapid detection of ovalbumin.  

PubMed

Egg allergy is an important public health and safety concern, so quantification and administration of food or vaccines containing ovalbumin (OVA) are urgently needed. This study aimed to establish a rapid and sensitive magnetic particles-chemiluminescence enzyme immunoassay (MPs-CLEIA) for the determination of OVA. The proposed method was developed on the basis of a double antibodies sandwich immunoreaction and luminol-H2O2 chemiluminescence system. The MPs served as both the solid phase and separator, the anti-OVA MPs-coated polyclonal antibodies (pAbs) were used as capturing antibody, and the horseradish peroxidase (HRP)-labeled monoclonal antibody (mAb) was taken as detecting antibody. The parameters of the method were evaluated and optimized. The established MPs-CLEIA method had a linear range from 0.31 to 100ng/ml with a detection limit of 0.24ng/ml. The assays showed low reactivities and less than 5% of intraassay and interassay coefficients of variation (CVs), and the average recoveries were between 92 and 97%. Furthermore, the developed method was applied in real samples analysis successfully, and the correlation coefficient with the commercially available OVA kit was 0.9976. Moreover, it was more rapid and sensitive compared with the other methods for testing OVA. PMID:24769049

Feng, Xiao-Li; Ren, Hong-Lin; Li, Yan-Song; Hu, Pan; Zhou, Yu; Liu, Zeng-Shan; Yan, Dong-Ming; Hui, Qi; Liu, Dong; Lin, Chao; Liu, Nan-Nan; Liu, Yan-Yan; Lu, Shi-Ying

2014-08-15

187

Using a large area CMOS APS for direct chemiluminescence detection in Western blotting electrophoresis  

NASA Astrophysics Data System (ADS)

Western blotting electrophoretic sequencing is an analytical technique widely used in Functional Proteomics to detect, recognize and quantify specific labelled proteins in biological samples. A commonly used label for western blotting is Enhanced ChemiLuminescence (ECL) reagents based on fluorescent light emission of Luminol at 425nm. Film emulsion is the conventional detection medium, but is characterized by non-linear response and limited dynamic range. Several western blotting digital imaging systems have being developed, mainly based on the use of cooled Charge Coupled Devices (CCDs) and single avalanche diodes that address these issues. Even so these systems present key drawbacks, such as a low frame rate and require operation at low temperature. Direct optical detection using Complementary Metal Oxide Semiconductor (CMOS) Active Pixel Sensors (APS)could represent a suitable digital alternative for this application. In this paper the authors demonstrate the viability of direct chemiluminescent light detection in western blotting electrophoresis using a CMOS APS at room temperature. Furthermore, in recent years, improvements in fabrication techniques have made available reliable processes for very large imagers, which can be now scaled up to wafer size, allowing direct contact imaging of full size western blotting samples. We propose using a novel wafer scale APS (12.8 cm×13.2 cm), with an array architecture using two different pixel geometries that can deliver an inherently low noise and high dynamic range image at the same time representing a dramatic improvement with respect to the current western blotting imaging systems.

Esposito, Michela; Newcombe, Jane; Anaxagoras, Thalis; Allinson, Nigel M.; Wells, Kevin

2012-03-01

188

Electrochemiluminescence of luminol enhanced by the synergetic catalysis of hemin and silver nanoparticles for sensitive protein detection.  

PubMed

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). PMID:24240164

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

2014-04-15

189

Chemiluminescent Oscillating Demonstrations: The Chemical Buoy, the Lighting Wave, and the Ghostly Cylinder  

ERIC Educational Resources Information Center

Oscillating reactions have been extensively used in chemical demonstrations. They involve several chemical concepts about kinetics, catalysts, and thermodynamics. The spontaneous cyclic color change of a solution is an attraction in any educational-level course. Chemiluminescent reactions are also among the most fascinating demonstrations and have…

Prypsztejn, Hernan E.; Mulford, Douglas R.; Stratton, Doug

2005-01-01

190

A firefly inspired one-pot chemiluminescence system using n-propylphosphonic anhydride (T3P).  

PubMed

A simple reaction procedure for chemiluminescence of firefly luciferin (d-luc) using n-propylphosphonic anhydride (T3P) is reported. A luminescent photon is produced as a result of one-pot reaction, only requiring mixing with the substrate carboxylic acid and T3P in the presence of a mild organic base. PMID:25350893

Kato, Dai-Ichiro; Shirakawa, Daiki; Polz, Robin; Maenaka, Mika; Takeo, Masahiro; Negoro, Seiji; Niwa, Kazuki

2014-12-12

191

Multiplex chemiluminescent immunoassay for screening of mycotoxins using photonic crystal microsphere suspension array.  

PubMed

A novel multiplex chemiluminescent mycotoxin immunoassay suspension array system was developed by combining the silica photonic crystal microspheres (SPCMs) encoding technique and a chemiluminescent immunoassay (CLIA) method. The SPCMs were used as a carrier of the suspension array and encoded by their reflectance peak positions, which overcome fluorescence photobleaching, and the potential interference between the encoding fluorescence and detection fluorescence. Aflatoxin B1 (AFB1), fumonisin B1 (FB1) and ochratoxin A (OTA) artificial antigens were immobilized on the surfaces of SPCMs by using 3-glycidoxypropyltrimethoxysilane as a linker. Horseradish peroxidase (HRP) was used as a labeling enzyme for the secondary antibody in the enzyme-catalyze H2O2-luminol chemiluminescence system. The CLIA detection system was easily integrated with a multifunctional microplate reader and displayed a two to three orders of magnitude dynamic linear detection range from 0.001 to 1, 0.001 to 1, and 0.01 to 1 ng mL(-1) for AFB1, FB1 and OTA with 50% inhibitory concentrations (IC50) of 0.01, 0.036, and 0.04 ng mL(-1), respectively. The recovery rates are in the range of 63.5 to 121.6% for the three mycotoxins in three kinds of spiked cereal samples. The results of detection in 12 naturally contaminated cereal samples were consistent with that of the classic enzyme-linked immunosorbent assay (ELISA) method. This proposed system is simple, rapid, low cost and high throughput for multiplex mycotoxin assay. PMID:24352570

Xu, Kun; Sun, Yue; Li, Wei; Xu, Jie; Cao, Bin; Jiang, Yunkun; Zheng, Tiesong; Li, Jianlin; Pan, Daodong

2014-02-21

192

A post-column extraction system for the determination of tertiary amines by liquid chromatography with chemiluminescence detection  

Microsoft Academic Search

Summary  The combination of an ion-pair extraction detection system with peroxyoxalate chemiluminescence detection has been investigated.\\u000a Ion-pairs of protonated tertiary amines with a chemiluminescent counter ion are on-line post-column extracted to 1,2-dichloroethane\\u000a containing bis(2,4,6-trichlorophenyl)oxalate (TCPO). Hydrogen peroxide is added to the organic phase by means of a solid-state\\u000a perhydrit reactor. The influence of the base catalyst (imidazole) on the chemiluminescence reaction

P. J. M. Kwakman; U. A. Th. Brinkman; R. W. Frei; G. J. de Jong; F. J. Spruit; N. G. F. M. Lammers; J. H. M. van den Berg

1987-01-01

193

Chemiluminescence microanalysis of substrates and enzymes.  

PubMed

Extracts from bioluminescent organisms are increasingly used for analysis of small amounts of substrates and enzymes. The light emission is in some organisms related to the conversion of substrates and cofactors of central metabolic importance. Extracts from such organisms are particularly valuable for analytical applications. This is quite obvious in the firefly where the energy, required for light production, is derived from ATP and in a couple of strains of luminescent bacteria where reduced pyridine nucleotides through reduction of flavine mononucleotide is utilized in the light reaction. It deserved to be noted that many biochemical reactions can be coupled more or less directly to the conversion of ATP, NAD(H), NADP(H) and FMN(H), thus providing the basis for a great variety of analyses. Special kinds of bioluminescent reactions are also of considerable interest, as for instance the relationship between "active sulphate" and PAP, which participate in the formation of light in the sea pansy (Renilla reniformis). High sensitivities are often reached in chemiluminescence analysis making the technique suitable for samples composed of a small number of cells. How bioluminescence has been employed in these kinds of microanalyses is examplified in studies of nucleotides, metabolites and enzymes with low activities. PMID:14428

Brolin, S E; Wettermark, G; Hammar, H

1977-02-01

194

Facile chemiluminescent method for alkaline phosphatase determination  

Microsoft Academic Search

The determination of alkaline phosphatase activity is of wide applicability, both as a free enzyme or bound to antibodies (conjugates). Activity determinations employing chemiluminescent substrates have become increasingly important due to their high sensitivity, typically equivalent to or better than assays utilizing radioactive labels. We report here a new chemiluminescent methodology for the determination of alkaline phosphatase activity based on

Valdecir F. Ximenes; Ana Campa; Wilhelm J. Baader; Luiz H. Catalani

1999-01-01

195

Supramolecular assembly and nanostructures of a series of luminol derivatives with aromatic/alkyl substituted groups in Langmuir-Blodgett films.  

PubMed

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. PMID:24738403

Jiao, Tifeng; Xing, Yuanyuan; Zhang, Qingrui; Zhang, Li; Liu, Minghua; Zhou, Jingxin; Gao, Faming

2014-06-01

196

Determination of sibutramine with a new sensor based on luminol electrochemiluminescence  

Microsoft Academic Search

A flow injection electrochemiluminescence (FI-ECL) analysis method for the determination of sibutramine in the presence of luminol was studied under conventional cyclic voltammetry in alkaline Na2CO3–NaHCO3 buffer solution (pH 8.0–12.0). This method is based on the enhanced ECL of luminol–sibutramine. Meanwhile, in order to overcome the drawbacks of conventional cells, a FI cell was designed, which is reusable and has

Shaowei Wang; Jinghua Yu; Fuwei Wan; Shenguang Ge; Mei Yan; Meng Zhang

2011-01-01

197

A novel strategy for synthesis of hollow gold nanosphere and its application in electrogenerated chemiluminescence glucose biosensor.  

PubMed

Well-distributed hollow gold nanospheres (Aushell@GOD) (20 ± 5 nm) were synthesized using the glucose oxidase (GOD) cross-linked with glutaraldehyde as a template. A glucose biosensor was prepared based on Aushell@GOD nanospheres for catalyzing luminol electrogenerated chemiluminescence (ECL). Firstly, chitosan was modified in a glassy carbon electrode which offered an interface of abundant amino-groups to assemble Aushell@GOD nanospheres. Then, glucose oxidase was adsorbed on the surface of Aushell@GOD nanospheres via binding interactions between Aushell and amino groups of GOD to construct a glucose biosensor. The Aushell@GOD nanospheres were investigated with TEM and UV-vis. The ECL behaviors of the biosensor were also investigated. Results showed that, the obtained Aushell@GOD nanospheres exhibited excellent catalytic effect towards the ECL of luminol-H2O2 system. The response of the prepared biosensor to glucose was linear with the glucose concentration in the range of 1.0 ?M to 4.3mM (R=0.9923) with a detection limit of 0.3 ?M (signal to noise=3). This ECL biosensor exhibited short response time and excellent stability for glucose. At the same time the prepared ECL biosensor showed good reproducibility, sensitivity and selectivity. PMID:25059123

Zhong, Xia; Chai, Ya-Qin; Yuan, Ruo

2014-10-01

198

Turn-on chemiluminescent sensing platform for label-free protease detection using streptavidin-modified magnetic beads.  

PubMed

We report a label-free streptavidin-modified magnetic beads (SA-MBs)-based sensing platform for turn-on chemiluminescent (CL) detection of protease using trypsin as model analyte. In the assay, a biotinylated peptide containing an arginine and a terminal cysteine was used as the substrate of trypsin. Upon adding the peptide into a basic luminol-NaIO4 solution, the terminal cysteine induced a strong CL signal. Surprisingly a much lower CL was emitted when the peptide was immobilized on the surface of SA-MBs. Based on this phenomenon, we designed a turn-on CL sensing system for protease using trypsin as model and its inhibitors screening. In the absence of trypsin, the peptide was coupled to the SA-MBs surface, resulting in a low CL background. Upon the addition of trypsin, the peptide can be catalytically hydrolyzed at the C-terminus of arginine, resulting in the formation of free cysteine-containing residues and subsequent CL recovery with the addition of luminol and NaIO4. The simple method does not require washing or separating procedures. Trypsin at a concentration as low as 10 pM can be assayed using this new CL sensing system. Additionally, the proposed method can be employed for screening the inhibitors of trypsin. This new sensing strategy could be easily extended to assay other proteases by simply changing the peptide substrate. PMID:24846776

Zhang, Huanhuan; Yu, Dalong; Zhao, Yanjun; Fan, Aiping

2014-11-15

199

A critical evaluation of a flow-cell based on a liquid core waveguide for chemiluminescence measurements.  

PubMed

Liquid-core waveguides (LCWs), devices that constrain the emitted radiation minimizing losses during the transport, are an alternative to maximize the amount of detected radiation in luminescence. In this work, the performance of a LCW flow-cell was critically evaluated for chemiluminescence measurements, by using as model the oxidation of luminol by hydrogen peroxide or hypochlorite. An analytical procedure for hypochlorite determination was also developed, with linear response in the range 0.2-3.8 mg/L (2.7-51 micromol/L), a detection limit estimated as 8 microg/L (0.64 micromol/L) at the 99.7% confidence level and luminol consumption of 50 microg/determination. The coefficients of variation were 3.3% and 1.6% for 0.4 and 1.9 mg/L ClO(-), respectively, with a sampling rate of 164 determinations/h. The procedure was applied to the analysis of Dakin's solution samples, yielding results in agreement with those obtained by iodometric titration at the 95% confidence level. PMID:18814188

Sanchez, Mariana A; Rocha, Fábio R P

2008-01-01

200

Optical sensor for the determination of glucose based on KIO4 chemiluminescence detection.  

PubMed

A method to determine glucose using an optical sensor prepared by entrapping glucose oxidase into silica sol-gel column has been developed. The silica sol-gel film was coated on alumina substrate. The optical sensor is based on the chemiluminescence intensity from the reaction of periodate and hydrogen peroxide in K2CO3 medium. The effect of the ratio of water and alcohol for the preparation of TEOS sol on chemiluminescence intensity was investigated. The effects of pH of enzyme reactor, concentrations of potassium periodate and SDS, and flow rate on the chemiluminescence intensity were studied to find the optimum experimental conditions to determine glucose. The chemiluminescence intensity increased linearly with increasing glucose concentration from 5.0 x 10(-4) M to 1.0 x 10(-7) M and the detection limit was 4.0 x 10(-8) M. Interference effects from some metal ions on chemiluminescence intensity were also investigated. PMID:15617266

Li, Ming; Lee, Sang Hak; Bae, Zun Ung; Lee, Kwang Pill; Park, Yu Chul; Lee, Mu Sang

2004-09-01

201

Analytical Applications of Bioluminescence and Chemiluminescence  

NASA Technical Reports Server (NTRS)

Bioluminescence and chemiluminescence studies were used to measure the amount of adenosine triphosphate and therefore the amount of energy available. Firefly luciferase - luciferin enzyme system was emphasized. Photometer designs are also considered.

Chappelle, E. W. (editor); Picciolo, G. L. (editor)

1975-01-01

202

HALOCARBON INTERFERENCES IN CHEMILUMINESCENT MEASUREMENTS OF NOX  

EPA Science Inventory

Anomalous NOx responses were observed when halocarbons were irradiated in the presence of oxides of nitrogen. Interferences to chemiluminescent NOx monitor using heated carbon converter were studied for phosgene, tri-chloroacetyl chloride, chloroform, chlorine, and hydrochloric a...

203

Applications of Nanomaterials in Electrogenerated Chemiluminescence Biosensors  

PubMed Central

Electrogenerated chemiluminescence (also called electrochemiluminescence and abbreviated ECL) involves the generation of species at electrode surfaces that then undergo electron-transfer reactions to form excited states that emit light. ECL biosensor, combining advantages offered by the selectivity of the biological recognition elements and the sensitivity of ECL technique, is a powerful device for ultrasensitive biomolecule detection and quantification. Nanomaterials are of considerable interest in the biosensor field owing to their unique physical and chemical properties, which have led to novel biosensors that have exhibited high sensitivity and stability. Nanomaterials including nanoparticles and nanotubes, prepared from metals, semiconductor, carbon or polymeric species, have been widely investigated for their ability to enhance the efficiencies of ECL biosensors, such as taking as modification electrode materials, or as carrier of ECL labels and ECL-emitting species. Particularly useful application of nanomaterials in ECL biosensors with emphasis on the years 2004-2008 is reviewed. Remarks on application of nanomaterials in ECL biosensors are also surveyed. PMID:22389624

Qi, Honglan; Peng, Yage; Gao, Qiang; Zhang, Chengxiao

2009-01-01

204

Storable, thermally activated, near-infrared chemiluminescent dyes and dye-stained microparticles for optical imaging  

NASA Astrophysics Data System (ADS)

Imaging techniques are a vital part of clinical diagnostics, biomedical research and nanotechnology. Optical molecular imaging makes use of relatively harmless, low-energy light and technically straightforward instrumentation. Self-illuminating, chemiluminescent systems are particularly attractive because they have inherently high signal contrast due to the lack of background emission. Currently, chemiluminescence imaging involves short-lived molecular species that are not stored but are instead generated in situ, and they typically emit visible light, which does not penetrate far through heterogeneous biological media. Here, we describe a new paradigm for optical molecular imaging using squaraine rotaxane endoperoxides, interlocked fluorescent and chemiluminescent dye molecules that have a squaraine chromophore encapsulated inside a macrocycle endoperoxide. Squaraine rotaxane endoperoxides can be stored indefinitely at temperatures below -20 °C, but upon warming to body temperature they undergo a unimolecular chemical reaction and emit near-infrared light that can pass through a living mouse.

Baumes, Jeffrey M.; Gassensmith, Jeremiah J.; Giblin, Jay; Lee, Jung-Jae; White, Alexander G.; Culligan, William J.; Leevy, W. Matthew; Kuno, Masaru; Smith, Bradley D.

2010-12-01

205

Long-lived chemiluminescence in cigarette smoke  

Microsoft Academic Search

Cigarette smoke contains high concentrations of unstable molecules that react with oxygen to produce chemiluminescence. The chemiluminescent activity concentrated in the aerosol phase that can be absorbed on glass-fiber filters and extracted into organic solvents. Cigarette smoke in N,N-dimethylformamide produces a long-lasting luminescence visible to the dark-adapted eye. We have demonstrated the oxygen dependence and have measured the kinetics, activation

H. H. Seliger; W. H. Biggley; J. P. Hamman

1974-01-01

206

Sorption of platinum on immobilized microorganisms for its on-line preconcentration and chemiluminescent determination in water samples.  

PubMed

Fungi of the type Aspergillus sp. were immobilized on a cellulosic resin and used as a biosorbent for the on-line preconcentration and separation of Pt(IV) ions prior to their chemiluminescent determination via flow injection analysis. Biosorption and elution conditions were optimized, and the results compared to biosorbents based on the use of Chlorella vulgaris algae and Saccharomyces cerevisiae yeast in terms of preconcentration and selective retention of Pt(IV). The immobilized fungi presented here have a high potential for use in platinum biosorption. The procedure exhibits the currently lowest limit of detection (0.02 ng mL(-1) of Pt) and very high selectivity. The procedure was applied to the determination of Pt(IV) in river water, road run-off, and wastewater samples.FigureSchematic diagram of flow injection manifold for on-line preconcentration/separation of Pt(IV) on immobilized fungi followed by its luminol-based chemiluminescent determination. The CL-FIA manifold was applied to the determination of platinum in river water, road run-off, and wastewater samples. PMID:22347728

Malejko, Julita; Szyga?owicz, Marzena; Godlewska-?y?kiewicz, Beata; Koj?o, Anatol

2012-02-01

207

Relative independence of luminol-enhanced intensity of photon emission during oxidative burst from nondiluted human blood on the volume and surface area of the sample  

NASA Astrophysics Data System (ADS)

Parameters of chemiluminescence (CL) from nondiluted human blood were studied. Kinetics and intensity of CL depended upon donor's state of health, time after blood extravasion, conditions of its storage, conditions of its counting. Peculiar dependence of Luminol-enhanced CL on sample volume changes during respiratory burst (RB) was revealed. When 0.5 ml aliquots were consecutively taken from blood and transferred into another vial of the same configuration, each subtraction of blood was followed by an acceleration of CL intensity growth. Summation of portions of blood in the second vial resulted in deceleration of CL intensity increase from it. At equal volumes of blood CL intensity from the first sample was manifold higher than from the second one and this difference was increasing on with further transfers. When blood was transferred back to the first sample, CL intensity from the 'donor' sample began to increase at a faster rate, while CL intensity from the 'recipient' sample stabilized. Such behavior was characteristic of nondiluted healthy donors' blood. Diluted blood or blood of sick people demonstrated different behavior. It is suggested that CL parameters of nondiluted blood may be informative of integrative properties of blood tissue.

Voeikov, Vladimir L.; Novikov, Cyril N.

1997-05-01

208

Selective Detection of Neurotransmitters by Fluorescence and Chemiluminescence Imaging  

SciTech Connect

In recent years, luminescence imaging has been widely employed in neurochemical analysis. It has a number of advantages for the study of neuronal and other biological cells: (1) a particular molecular species or cellular constituent can be selectively visualized in the presence of a large excess of other species in a heterogeneous environment; (2) low concentration detection limits can be achieved because of the inherent sensitivity associated with fluorescence and chemiluminescence; (3) low excitation intensities can be used so that long-term observation can be realized while the viability of the specimen is preserved; and (4) excellent spatial resolution can be obtained with the light microscope so subcellular compartments can be identified. With good sensitivity, temporal and spatial resolution, the flux of ions and molecules and the distribution and dynamics of intracellular species can be measured in real time with specific luminescence probes, substrates, or with native fluorescence. A noninvasive detection scheme based on glutamate dehydrogenase (GDH) enzymatic assay combined with microscopy was developed to measure the glutamate release in cultured cells from the central nervous system (CNS). The enzyme reaction is very specific and sensitive. The detection limit with CCD imaging is down to {micro}M levels of glutamate with reasonable response time. They also found that chemiluminescence associated with the ATP-dependent reaction between luciferase and luciferin can be used to image ATP at levels down to 10 nM in the millisecond time scale. Similar imaging experiments should be feasible in a broad spectrum of biological systems.

Ziqiang Wang; Edward S. Yeung

2001-08-06

209

Gold nanorods-enhanced rhodamine B-permanganate chemiluminescence and its analytical application  

NASA Astrophysics Data System (ADS)

A novel enhanced chemiluminescence system was developed by applying gold nanorods (Au NRs) as catalysts in rhodamine B-permanganate reaction. Au NRs with three different aspect ratios were synthesized by seed mediated growth method and characterized by UV-Vis spectra and transmission electron microscopy. It was demonstrated that Au NRs have much higher catalytic effect than spherical nanoparticles on rhodamine B-permanganate chemiluminescence reaction. Among various sizes of Au NRs, those with average aspect ratio of 3.0 were found to have the most remarkable catalytic activity. As an analytical application of the new chemiluminescence system, albumin as a model protein was quantified based on its interaction with NRs. Albumin binds to Au NRs active surfaces and inhibits their catalytic action and therefore decreases the intensity of chemiluminescence. This diminution effect is linearly related to the concentration of the human and bovine serum albumin over the ranges of 0.45-90 and 0.75-123 nmol L-1, respectively with the corresponding limits of detection of 0.18 and 0.30 nmol L-1. The method was successfully applied to the determination of albumin in human and bovine serum samples.

Hassanzadeh, Javad; Amjadi, Mohammad; Manzoori, Jamshid L.; Sorouraddin, Mohammad Hossein

2013-04-01

210

On the photophysical properties of new luminol derivatives and their synthetic phthalimide precursors.  

PubMed

The photophysical properties of a series of structurally related 4-aminophthalimides and the corresponding 5-aminophthalic hydrazides (luminols) are reported. Absorption, steady-state, and time-resolved fluorescence spectra of luminols exhibited substitution, solvent, and pH dependence. Singlet lifetimes have been determined by time-resolved laser flash spectroscopy. UV spectra in gas phase and DMSO solution were calculated by TD-DFT which revealed the existence of two low-energy excited singlet states with strong pH-sensitivity. PMID:20111987

Pérez-Ruiz, Raúl; Fichtler, Robert; Diaz Miara, Yrene; Nicoul, Matthieu; Schaniel, Dominik; Neumann, Helfried; Beller, Matthias; Blunk, Dirk; Griesbeck, Axel G; Jacobi von Wangelin, Axel

2010-05-01

211

Ultra-sensitive, high-throughput detection of infectious diarrheal diseases by portable chemiluminescence imaging.  

PubMed

This paper describes a rapid, ultra-sensitive, and high-throughput pathogenic DNA identification strategy for infectious diarrheal diseases diagnosis. This strategy is based on specific DNA hybridization and horseradish-peroxidase-catalyzed chemiluminescence (CL) detection. Probe DNA strands are covalently immobilized on the aldehyde-group-modified slide and hybridized with biotin-modified target DNA strands. Horseradish-peroxidase (HRP) is then combined with the target DNA via a biotin-streptavidin linkage. The subsequently added mixture of luminol and hydrogen peroxide is catalyzed by HRP and radiates photons. The photons are collected and read out by a portable imager. The specific detection of target DNA strands was realized at a detection limitation of about 0.75 nM. This strategy facilitates quantitative detection, as indicated by the fact that the CL signals were consistent well with a linear function. This method was applied to identify a myriad of real diarrheal pathogens samples, including Enterohemorrhagic Escherichia coli (EHEC), Vibrio cholerae (VBC), Shigella (SHLA), and Salmonella (SMLA). Triple-assay of six gene sequences from these pathogens was realized, which facilitates accurate, high-throughput identification of diarrheal pathogens. This CL assay strategy is appropriate for application in disease diagnosis and prevention. PMID:24534578

Wang, Chaoguang; Xiao, Rui; Dong, Peitao; Wu, Xuezhong; Rong, Zhen; Xin, Lin; Tang, Jun; Wang, Shengqi

2014-07-15

212

Chemiluminescence response induced by mesenteric ischaemia/reperfusion: effect of antioxidative compounds ex vivo  

PubMed Central

Ischaemia and reperfusion (I/R) play an important role in human pathophysiology as they occur in many clinical conditions and are associated with high morbidity and mortality. Interruption of blood supply rapidly damages metabolically active tissues. Restoration of blood flow after a period of ischaemia may further worsen cell injury due to an increased formation of free radicals. The aim of our work was to assess macroscopically the extent of intestinal pathological changes caused by mesenteric I/R, and to study free radical production by luminol enhanced chemiluminescence (CL) of ileal samples. In further experiments, the antioxidative activity of the drugs tested was evaluated spectrophotometrically by the use of the DPPH radical. We studied the potential protective ex vivo effect of the plant origin compound arbutin as well as of the pyridoindole stobadine and its derivative SMe1EC2. I/R induced pronounced haemorrhagic intestinal injury accompanied by increase of myeloperoxidase (MPO) and N-acetyl-?-D-glucosaminidase (NAGA) activity. Compared to sham operated (control) rats, there was only a slight increase of CL response after I/R, probably in association with neutrophil increase, indicated by enhanced MPO activity. All compounds significantly reduced the peak values of CL responses of the ileal samples ex vivo, thus reducing the I/R induced increase of free radical production. The antioxidants studied showed a similar inhibitory effect on the CL response influenced by mesenteric I/R. If proved in vivo, these compounds would represent potentially useful therapeutic antioxidants. PMID:21217883

Nosal'ova, Viera; Sotnikova, Ruzena; Drabikova, Katarina; Fialova, Silvia; Kostalova, Daniela; Banasova, Silvia; Navarova, Jana

2010-01-01

213

Chemiluminescence detection of protein in capillary electrophoresis using aptamer-functionalized gold nanoparticles as biosensing platform.  

PubMed

Highly sensitive and selective detection of disease-related proteins play critical roles in clinical practice and diagnostic assays. Herein, we proposed a highly selective and ultrasensitive chemiluminescence (CL) method for protein detection in capillary electrophoresis (CE) using aptamer-functionalized gold nanoparticles (AuNPs) as biosensing platform. In this protocol, AuNPs were synthesized and conjugated with aptamer to form AuNPs-aptamer. Using thrombin and thrombin binding aptamer as an initial proof-of-concept recognization pair, AuNPs-aptamer was linked to thrombin to produce an AuNPs-aptamer-thrombin complex. The resulted complex and unbound AuNPs-aptamer were separated in CE and detected with luminol-H2O2 CL system. The developed strategy produced an ultrasensitive detection of thrombin down to 13.5 fmol/L (S/N=3) with a linear range from 0.033 to 66.0 pmol/L. The application of the present protocol was demonstrated by analyzing thrombin in human plasma samples with the recoveries of 87.6-116.8%. This novel strategy has many outstanding merits including high specificity of aptamer, excellent catalysis behavior of AuNPs, high sensitivity of CL detection, and high separation efficiency of CE. PMID:24679407

Liu, Yanming; Liu, Yingying; Zhou, Min; Huang, Kejing; Cao, Juntao; Wang, Hui; Chen, Yonghong

2014-05-01

214

Fe(III)-TAML activator: a potent peroxidase mimic for chemiluminescent determination of hydrogen peroxide.  

PubMed

Efforts to replace native peroxidase with its low molecular weight alternatives have stimulated a search for peroxidase mimetics. Herein we describe the oxidation of luminol with hydrogen peroxide catalyzed by commercially available Fe(III)-TAML activator 1a, which was shown to be a more active catalyst than hemin. At Fe(III)-TAML activator 1a use in chemiluminescent assay for H2O2 determination the detection limit value (3?) of 5×10(-8)M was similar to the detection limit obtained with horseradish peroxidase (1×10(-7)M) and significantly lower than that obtained in the presence of hemin (6×10(-7)M). The linear ranges (R(2)=0.98) of the assay were 6×10(-8)-1×10(-6)M and 6×10(-7)-1×10(-6)M H2O2 for Fe(III)-TAML 1a and hemin, respectively. The CV values for Fe(III)-TAML 1a-based assay measured within the working range varied from 1.0% to 3.7% (n=4), whereas in the case of hemin -5.0% to 9.7% (n=4). Moreover, the sensitivity of Fe(III)-TAML 1a-based method was 56 and 5 times higher than that of hemin- and HRP-based methods, respectively. The obtained results open good perspectives to apply Fe(III)-TAML activator 1a in CL analytical methods instead of hemin, a traditionally used peroxidase mimetic. PMID:24840457

Vdovenko, Marina M; Demiyanova, Alexandra S; Kopylov, Kirill E; Sakharov, Ivan Yu

2014-07-01

215

Determination of phenol at ng l -1 level by flow-injection chemiluminescence combined with on-line solid-phase extraction  

NASA Astrophysics Data System (ADS)

In this paper, a simple flow-injection chemiluminescence (CL) system combined with on-line solid-phase extraction is presented to determine phenol. This method is based on the enhancement effect of phenol on the luminol-K 3Fe(CN) 6 CL system. The solid-phase extraction promised the high sensitivity and improved selectivity of CL detection. With the calibration range from 4.7 ng l -1 to 470 ng l -1 phenol concentration, the proposed method was applied to analyzing phenol in water samples and the obtained results were validated by the standard method. The detection limit was determined as 0.66 ng l -1. The relative standard deviation was 1.5% for determining 4.7 ng l -1 phenol standard ( n = 7).

Qi, Huili; Lv, Jiagen; Li, Baoxin

2007-04-01

216

Highly sensitive flow-injection chemiluminescence determination of pyrogallol compounds  

NASA Astrophysics Data System (ADS)

A highly sensitive flow-injection chemiluminescent method for the direct determination of pyrogallol compounds has been developed. Proposed method is based on the enhanced effect of pyrogallol compounds on the chemiluminescence signals of KMnO 4-H 2O 2 system in slightly alkaline medium. Three important pyrogallol compounds, pyrogallic acid, gallic acid and tannic acid, have been detected by this method, and the possible mechanism of the CL reaction is also discussed. The proposed method is simple, convenient, rapid (60 samples h -1), and sensitive, has a linear range of 8 × 10 -10 mol L -1 to 1 × 10 -5 mol L -1, for pyrogallic acid, with a detection limit of 6 × 10 -11 mol L -1, 4 × 10 -8 mol L -1 to 5 × 10 -3 mol L -1 for gallic acid with a detection limit of 9 × 10 -10 mol L -1, and 8 × 10 -8 mol L -1 to 5 × 10 -2 mol L -1 for tannic acid, with a detection limit of 2 × 10 -9 mol L -1, respectively. The relative standard deviation (RSD, n = 15) was 0.8, 1.1 and 1.3% for 5 × 10 -6 mol L -1 pyrogallic acid, gallic acid and tannic acid, respectively. The proposed method was successfully applied to the determination of pyrogallol compounds in tea and coffee samples.

Kanwal, Shamsa; Fu, Xiaohong; Su, Xingguang

2009-12-01

217

Gold nanoparticles bifunctionalized by chemiluminescence reagent and catalyst metal complexes: synthesis and unique chemiluminescence property.  

PubMed

Despite much progress in functionalized gold nanomaterial (GNMs), chemiluminescent (CL) functionalized GNMs with high CL efficiency are far from fully developed. In this work, we report a general strategy for the synthesis of gold nanoparticles (GNPs) bifunctionalized by CL reagent and catalyst metal complexes (BF-GNPs) by taking N-(aminobutyl)-N-(ethylisoluminol) (ABEI) as a model of CL reagents. The complexes of 2-[bis[2-[carboxymethyl-[2-oxo-2-(2-sulfanylethylamino)ethyl]amino]ethyl]amino]acetic acid (DTDTPA) with various metal ions, including Co(2+), Cu(2+), Pb(2+), Ni(2+), Hg(2+), Cr(3+), Eu(3+), La(3+), Gd(3+), Sm(3+), Er(3+), Dy(3+), Ce(4+), and Ce(3+), were grafted on the surface of ABEI functionalized GNPs (ABEI-GNPs) to form a series of BF-GNPs. These BF-GNPs exhibited excellent CL activity. In particular, the CL intensity of DTDTPA/Co(2+)-ABEI-GNPs was over 3 orders of magnitude higher than ABEI-GNPs. This work demonstrates for the first time that metal complexes grafted on the surface of GNPs have unique catalytic activity on the CL reaction, superior to that in the liquid phase. Such BF-GNPs may find future applications in bioassays, microchips, and molecular/cellular imaging. PMID:24593264

Liu, Mengxiao; Zhang, Hongli; Shu, Jiangnan; Liu, Xiaoyang; Li, Fang; Cui, Hua

2014-03-18

218

Chemiluminescence Study of the Autoxidation of cis-1,4-Polyisoprene  

NASA Technical Reports Server (NTRS)

The free-radical mechanism for the autoxidation of cis-1,4-polyisoprene (natural rubber or its synthetic counterpart) has been investigated extensively. An important feature of this mechanism, and indeed also of the autoxidation of hydrocarbons generally, is that it is a chain process propagated by alkyl and peroxy radicals and terminated through bimolecular reactions involving these same radicals. In the usual oxidation situation, that is, at all oxygen pressures greater than a few torr, the alkyl radicals are rapidly converted to peroxy radicals, and the termination step proceeds almost exclusively through the latter radicals. The bimolecular decay of the peroxy radicals is accompanied by a weak emission of light or chemiluminescence. Kinetic evidence is consistent with an electronically excited ketone produced in the termination reaction as the source of the emission. The first observation of chemiluminescence from the oxidative degradation of polymers was reported by Ashby, who dealt mainly with polypropylene but made passing mention of several other polymers. Subsequently, a number of papers have appeared dealing with oxidative chemiluminescence from a variety of polymers. In this paper we report the first detailed study of the chemiluminescence emitted in the autoxidation of cis-1,4-polyisoprene. The chemiluminescence technique is extremely sensitive and can follow rates of oxidation that are too slow to be measured conveniently by other means. This work thus offered the potential of throwing new light on the autoxidation of cis-1,4-polyisoprene, especially in the very early stages or under ambient conditions where conventional spectroscopic procedures are rather insensitive.

Mendenhall, G. David; Nathan, Richard A.; Golub, Morton A.

1978-01-01

219

CuO nanosheets-enhanced flow-injection chemiluminescence system for determination of vancomycin in water, pharmaceutical and human serum  

NASA Astrophysics Data System (ADS)

A novel, rapid and sensitive CuO nanosheets (NSs) amplified flow-injection chemiluminescence (CL) system, luminol-H2O2-CuO nanosheets, was developed for determination of the vancomycin hydrochloride for the first time. It was found that vancomycin could efficiently inhibit the CL intensity of luminol-H2O2-CuO nanosheets system in alkaline medium. Under the optimum conditions, the inhibited CL intensity was linearly proportional to the concentration of vancomycin over the ranges of 0.5-18.0 and 18.0-40.0 mg L-1, with a detection limit (3?) of 0.1 mg L-1. The precision was calculated by analyzing samples containing 5.0 mg L-1 vancomycin (n = 11) and the relative standard deviation (RSD) was 2.8%. Also, a high injection throughput of 120 sample h-1 was obtained. The CuO nanosheets were synthesized by a sonochemical method. Also, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were employed to characterize the CuO nanosheets. The method was successfully employed to determine vancomycin hydrochloride in environmental water samples, pharmaceutical formulation and spiked human serum.

Khataee, A. R.; Hasanzadeh, A.; Iranifam, M.; Fathinia, M.; Hanifehpour, Y.; Joo, S. W.

2014-03-01

220

OPTIMIZED CHEMILUMINESCENCE SYSTEM FOR MEASURING ATMOSPHERIC AMMONIA  

EPA Science Inventory

The optimization and testing of a continuous measurement system for analyzing atmospheric ammonia concentrations (0 to 10 ppb) is described. The measurement system combines an ultra-sensitive chemiluminescence nitric oxide detector, with a thermal converter for NH3 to nitric oxid...

221

Lacrimal outflow patency demonstrated by chemiluminescence.  

PubMed

A chemiluminescent material (Cyalume) was injected into the lacrimal excretory passages of eight normal monkeys (16 eyes). Patency was established by almost instantaneous observation of a yellowish-green glow in the nose and pharynx. No toxic effects of the chemical were noted in any of the monkeys. PMID:6766299

Cohen, S W; Sherman, M; Schwartz, G G; Banko, W; Cohen, H H; Mahl, C F

1980-01-01

222

Illustrating Chemiluminescence with Siloxene Indicator.  

ERIC Educational Resources Information Center

Discusses the nature of light-producing reactions and provides a procedure for demonstrating chemical luminescence using siloxene indicator. Indicates source of this chemical and safety precautions. (SK)

Hoff, Ray

1981-01-01

223

New method for the photo-chemiluminometric determination of benzoylurea insecticides based on acetonitrile chemiluminescence.  

PubMed

The viability of tandem photochemical reaction-chemiluminescence detection has been studied for the determination of five benzoylurea insecticides, namely, diflubenzuron, triflumuron, hexaflumuron, lufenuron and flufenoxuron. The 'on-line' photochemical reaction of benzoylurea pesticides provides an enhanced chemiluminescence response of the pesticides during their oxidation by potassium hexacyanoferrate(III) and sodium hydroxide, whose signal increases with the percentage of acetonitrile in the reaction medium. The determination was performed using a photoreactor consisting of a PFA (perfluoroalkoxy) tube reactor coil (5 mx1.6-mm O.D. and 0.8-mm I.D.) and an 8-W xenon lamp. As the yield of the photoderivatization process and the chemiluminescent signals depend on the percentage of acetonitrile, the chromatographic column (a Gemini C18, Phenomenex 150 mmx4.6 mm, 5-microm particle size) was chosen with the aim of using high percentages of this organic solvent in the mobile phase. Previous studies showed that the rate of the chemiluminescent reaction was very fast. Therefore, a modification was carried out in the detector in order to mix the analytes and reactants as near as possible to the measure cell. The optimised method was validated with respect to linearity, precision, limits of detection and quantification accuracy. Under the optimised conditions, linear working range extends three orders of magnitude with the relative standard deviation of intra-day precision below 10% and detection limits between 0.012 and 0.18 microg mL-1, according to the compound. The proposed method has been successfully applied to the determination of benzoylureas in cucumber with good results. PMID:17205265

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

2007-03-01

224

Chemiluminescence determination of ferulic acid by flow-injection analysis using cerium(IV) sensitized by rhodamine 6G  

NASA Astrophysics Data System (ADS)

A simple, sensitive and rapid flow-injection chemiluminescence method has been developed for the determination of ferulic acid based on the chemiluminescence reaction of ferulic acid with rhodamine 6G and ceric sulfate in sulphuric acid medium. Strong chemiluminescence signal was observed when ferulic acid was injected into the acidic ceric sulfate solution in a flow-cell. The present method allowed the determination of ferulic acid in the concentration range of 8.0 × 10 -6 to 1.0 × 10 -4 mol l -1 and the detection limit for ferulic acid was 8.7 × 10 -9 mol l -1. The relative standard deviation was 2.4% for 10 replicate analyses of 1.0 × 10 -5 mol l -1 ferulic acid. The proposed method was applied to the determination of ferulic acid in Taita Beauty Essence samples with satisfactory results.

Wang, Ju Peng; Li, Nian Bing; Luo, Hong Qun

2008-11-01

225

Internal detection of surface plasmon coupled chemiluminescence during chlorination of potassium thin films  

NASA Astrophysics Data System (ADS)

The interaction of chlorine with potassium surfaces is a prototype reaction with a strong non-adiabatic energy transfer leading to exoemission and chemiluminescence. Thin film K/Ag/p-Si(111) Schottky diodes with 8 nm potassium on a 5-200 nm thick Ag layer are used as 2?-photodetectors for the chemiluminescence during chlorination of the K film at 110 K. The observed photocurrent shows a sharp maximum for small exposures and decreases gradually with the increasing chloride layer. The time dependence can be explained by the reaction kinetics, which is governed initially by second-order adsorption processes followed by an electric field-assisted diffusion. The detector current corresponds to a yield of a few percent of elementary charge per reacting chlorine molecule and is orders of magnitude larger than for external detection. The photoyield can be enhanced by increasing the Ag film thickness. For Ag films of 30 and 50 nm, the yield exhibits a maximum indicating surface plasmon coupled chemiluminescence. Surface plasmon polaritons in the Ag layer are excited by the reaction and decay radiatively into Si leading to the observed currents. A model calculation for the reverse process in attenuated total reflection is applied to explain the observed current yield maxima.

Becker, Felix; Krix, David; Hagemann, Ulrich; Nienhaus, Hermann

2013-01-01

226

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

PubMed

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. PMID:25199068

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

2014-09-18

227

Automated chemiluminescent assay for C-peptide.  

PubMed

C-peptide is secreted in equimolar concentrations with insulin, and is often measured to assess pancreatic beta-cell function. C-peptide analysis is most often performed by radioimmunoassay (RIA) which has several disadvantages. We evaluated an automated, chemiluminescent immunoassay for C-peptide in terms of precision, linearity, interference, and correlation with a RIA method. The chemiluminescent assay demonstrated acceptable correlation with the RIA method (slope = 0.82, y-intercept = 0.88 ng/ml, r-value = 0.97). Between-run Cvs ranged from 8 to 9%, which compared well with the RIA method. Linearity extended beyond the manufacturer's recommendations and recovery ranged from 87 to 112% across the concentrations tested, with a slope of 1.007. No significant interference was noted with hemoglobin, bilirubin, or triglyceride. Overall this method compared favorably with the RIA method and offers an alternative to RIA for the analysis of C-peptide. PMID:10645980

Hardy, R W; Cohn, M; Konrad, R J

2000-01-01

228

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

PubMed

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 ?-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. PMID:24769071

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

2014-07-15

229

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

NASA Technical Reports Server (NTRS)

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)).

Bairai, Solomon T.; Stedman, Donald H.

1992-01-01

230

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

PubMed

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. PMID:10914590

Della Manna, A; Montpetit, S

2000-07-01

231

Research Article Chemiluminescent Nanomicelles for Imaging Hydrogen Peroxide and Self-Therapy in Photodynamic Therapy  

E-print Network

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Hydrogen peroxide is a signal molecule of the tumor, and its overproduction makes a higher concentration in tumor tissue compared to normal tissue. Based on the fact that peroxalates can make chemiluminescence with a high efficiency in the presence of hydrogen peroxide, we developed nanomicelles composed of peroxalate ester oligomers and fluorescent dyes, called peroxalate nanomicelles (POMs), which could image hydrogen peroxide with high sensitivity and stability. The potential application of the POMs in photodynamic therapy (PDT) for cancer was also investigated. It was found that the PDT-drug-loaded POMs were sensitive to hydrogen peroxide, and the PDT drug could be stimulated by the chemiluminescence from the reaction between POMs and hydrogen peroxide, which carried on a self-therapy of the tumor without the additional laser light resource. 1.

Rui Chen; Luzhong Zhang; Jian Gao; Wei Wu; Yong Hu; Xiqun Jiang

232

Flow injection-chemiluminescence determination of dopamine using potassium permanganate and formaldehyde system  

NASA Astrophysics Data System (ADS)

A simple and sensitive flow injection-chemiluminescence method for the determination of dopamine has been proposed. The method is based on the enhancing effect of dopamine on the chemiluminescence emission generated by the reaction of potassium permanganate with formaldehyde in an acidic medium. The proposed procedure allows the determination of dopamine over the concentration range of 3.1 × 10-8-1.7 × 10-5 mol/L and with a detection limit of 1.0 × 10-8 mol/L. The linear regression equation was F = 44.4912 + 1.07 × 109 ? C (correlation coefficient, r2 = 0.9998). The relative standard deviation is 2.1% for the determination of 1.0 × 10-8 mol/L dopamine (n = 11). The method was successfully applied to the determination of dopamine in pharmaceutical preparation with satisfactory results. The recoveries were found in the range of 96.5-101.3%.

Wabaidur, Saikh Mohammad; Alothman, Zeid Abdullah; Alam, Seikh Mafiz; Lee, Sang Hak

2012-10-01

233

Laser-initiated chemical chain reactions  

Microsoft Academic Search

A detailed kinetic and experimental analysis is presented for chemical chain reaction processes initiated by well-controlled, low power laser pulses. Realtime evolution of the chain reaction is followed by direct detection of infrared chemiluminescence from vibrationally excited HCl product molecules produced by one of the propagation reactions in the chain. By appropriate choice of conditions, the chain reactions may be

David J. Nesbitt; Stephen R. Leone

1980-01-01

234

Photoluminescence, chemiluminescence and anodic electrochemiluminescence of hydrazide-modified graphene quantum dots.  

PubMed

Single-layer graphene quantum dots (SGQDs) were refluxed with hydrazine (N2H4) to prepare hydrazide-modified SGQDs (HM-SGQDs). Compared with SGQDs, partial oxygen-containing groups have been removed from HM-SGQDs. At the same time, a lot of hydrazide groups have been introduced into HM-SGQDs. The introduced hydrazide groups provide HM-SGQDs with a new kind of surface state, and give HM-SGQDs unique photoluminescence (PL) properties such as blue-shifted PL emission and a relatively high PL quantum yield. More importantly, the hydrazide-modification made HM-SGQDs have abundant luminol-like units. Accordingly, HM-SGQDs exhibit unique and excellent chemiluminescence (CL) and anodic electrochemiluminescence (ECL). The hydrazide groups of HM-SGQDs can be chemically oxidized by the dissolved oxygen (O2) in alkaline solutions, producing a strong CL signal. The CL intensity is mainly dependent on the pH value and the concentration of O2, implying the potential applications of HM-SGQDs in pH and O2 sensors. The hydrazide groups of HM-SGQDs can also be electrochemically oxidized in alkaline solutions, producing a strong anodic ECL signal. The ECL intensity can be enhanced sensitively by hydrogen peroxide (H2O2). The enhanced ECL intensity is proportional to the concentration of H2O2 in a wide range of 3 ?M to 500 ?M. The detection limit of H2O2 was calculated to be about 0.7 ?M. The results suggest the great potential applications of HM-SGQDs in the sensors of H2O2 and bio-molecules that are able to produce H2O2 in the presence of enzymes. PMID:25132204

Dong, Yongqiang; Dai, Ruiping; Dong, Tongqing; Chi, Yuwu; Chen, Guonan

2014-10-01

235

Paper-based chromatographic chemiluminescence chip for the detection of dichlorvos in vegetables.  

PubMed

Paper chromatography was a big breakthrough in the early of 20th century but it is rarely used due to the long separation time and the diffusion on the sample spots. In this work, for the first time, a paper-based chemiluminescence (CL) analytical device combined with paper chromatography was developed for the determination of dichlorvos (DDV) in vegetables without complicated sample pretreatment. The paper chromatography separation procedure can be accomplished in 12 min on a paper support (0.8 × 7.0 cm(2)) by using 5 µL sample spotted on it. After sample developing, the detection area (0.8 × 1.0 cm(2)) was cut and inserted between two layers of water-impermeable single-sided adhesive tapes. The paper-based chip was made by attaching the middle layer of paper onto the bottom layer. Then it was covered by another tape layer, which was patterned by the cutting method to form a square hole (0.8 × 1.0 cm(2)) in it. 10 ?L mixed solution of luminol and H2O2 was dropped on the detection area to produce CL. A linear relationship was obtained between the CL intensity and the concentrations of DDV in the range between 10.0 ng mL(-1) and 1.0 ?g mL(-1)and the detection limit was 3.6 ng mL(-1). Water-soluble metal ions and vitamins can be developed at different spatial locations relative to DDV, eliminating interference with DDV during detection. The paper-based chromatographic chip can be successfully used for the determination of DDV without complicated sample preparation in vegetables. This study should, therefore, be suitable for rapid and sensitive detection of trace levels of organophosphate pesticides in environmental and food samples. PMID:24021659

Liu, Wei; Kou, Juan; Xing, Huizhong; Li, Baoxin

2014-02-15

236

Highly sensitive microfluidic competitive enzyme immunoassay based on chemiluminescence resonance energy transfer for the detection of neuron-specific enolase.  

PubMed

A microfluidic competitive enzyme immunoassay based on chemiluminescence resonance energy transfer (CRET) was developed for highly sensitive detection of neuron-specific enolase (NSE). The CRET system consisted of horseradish peroxidase (HRP)/luminol as a light donor and fluorescein isothiocyanate as an acceptor. When fluorescein isothiocyanate-labeled antibody binds with HRP-labeled antigen to form immunocomplex, the donor and acceptor are brought close each other and CRET occurs in the immunocomplex. In the MCE, the immunocomplex and excess HRP-NSE were separated, and the chemiluminescense intensity of immunocomplex was used to estimate NSE concentration. The calibration curve showed a linearity in the range of NSE concentrations from 9.0 to 950 pM with a correlation coefficient of 0.9964. Based on a S/N of 3, the detection limit for NSE determination was estimated to be 4.5 pM, which is two-order magnitude lower than that of without CRET detection. This assay was applied for NSE quantification in human serum. The obtained results demonstrated that the proposed immunoassay may serve as an alternative tool for clinical analysis of NSE. PMID:24723253

Yang, Tingzhen; Vdovenko, Marina; Jin, Xue; Sakharov, Ivan Yu; Zhao, Shulin

2014-07-01

237

Esterase coupled with the H2O2/horseradish peroxidase system triggers chemiluminescence from 2-methyl-1-propenylbenzoate: a potential analytical tool for esterase analysis.  

PubMed

The hydrolysis of 2-methyl-1-propenylbenzoate catalyzed by esterase produces 2-methyl-1-propenol, which can be subsequently oxidized by the H2O2/horseradish peroxidase (HRP) system to yield electronically excited triplet acetone. The level of luminescence elicited by this species is proportional to total esterase used, making it possible to determine as little as 2 pmol of esterase. Yet, its intensity can be enhanced several orders of magnitude by fluorescent acceptors like sodium 9,10-dibromoanthracene-2-sulfonate. The system works as a chemiluminescent reaction triggered by esterase and can be used to elaborate analytical assays to determine its activity. This chemiluminescence is also promoted by HRP conjugates instead of free HRP and, hence, this simple reaction system can also be used to develop sensitive chemiluminescent immunoassays based upon peroxidase activity. PMID:8714601

Yavo, B; Campa, A; Catalani, L H

1996-02-15

238

Reagentless chemiluminescence-based fiber optic sensors for regenerative life support in space  

NASA Astrophysics Data System (ADS)

The initial feasibility demonstration of a reagentless chemiluminescence based fiber optic sensor technology for use in advanced regenerative life support applications in space and planetary outposts is described. The primary constraints for extraterrestrial deployment of any technology are compatibility with microgravity and hypogravity environments; minimal size, weight, and power consumption; and minimal use of expendables due to the great expense and difficulty inherent to resupply logistics. In the current research, we report the integration of solid state flow through modules for the production of aqueous phase reagents into an integrated system for the detection of important analytes by chemiluminescence, with fiber optic light transmission. By minimizing the need for resupply expendables, the use of solid phase modules makes complex chemical detection schemes practical. For the proof of concept, hydrogen peroxide and glucose were chosen as analytes. The reaction is catalyzed by glucose oxidase, an immobilized enzyme. The aqueous phase chemistry required for sensor operation is implemented using solid phase modules which adjust the pH of the influent stream, catalyze the oxidation of analyte, and provide the controlled addition of the luminophore to the flowing aqueous stream. Precise control of the pH has proven essential for the long-term sustained release of the luminophore. Electrocatalysis is achieved using a controlled potential across gold mesh and gold foil electrodes which undergo periodic polarity reversals. The development and initial characterization of performance of the reagentless fiber optic chemiluminescence sensors are presented in this paper.

Atwater, James E.; Akse, James R.; DeHart, Jeffrey; Wheeler, Richard R., Jr.

1995-04-01

239

Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry  

SciTech Connect

This review covers the 2 year period since our last review (1) from January 2008 through December 2009. A computer search of Chemical Abstracts provided most of the references for this review. A search for documents written in English containing the terms fluorescence or phosphorescence or chemiluminescence published in 2008-2009 resulted in more than 100 000 hits. An initial screening reduced this number to approximately 23 000 publications that were considered for inclusion in this review. Key word searches of this subset provided subtopics of manageable size. Other citations were found through individual searches by the various authors who wrote a particular section of this review.

Powe, Aleeta [University of Louisville, Louisville; Das, Susmita [Louisiana State University; Lowry, Mark [Lousianna State University; El-Zahab, Bilal [Lousianna State University; Fakayode, Sayo [Winston-Salem State University; Geng, Maxwell [University of Iowa; Baker, Gary A [ORNL; Wang, Lin [Southern Illinois University; McCarroll, Matthew [Southern Illinois University; Patonay, Gabor [Georgia State University, Atlanta; Li, Min [Lousianna State University; Aljarrah, Mohannad [Louisiana State University; Neal, Sharon [University of Delaware; Warner, Isiah M [ORNL

2010-01-01

240

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

NASA Astrophysics Data System (ADS)

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 (? H) and entropy (? 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.

Moyon, N. Shaemningwar; Mitra, Sivaprasad

2010-09-01

241

A new technique for enhancing luminol luminescent detection of free radicals and reactive oxygen species.  

PubMed

A novel technique is reported which makes use of (1) an improved method for solubilizing luminol at neutral pH along with (2) the addition of dimethyl sulfoxide to stabilize superoxide anion in the solutions in which luminescence is detected. These improvements resulted in (1) very low blank values of luminescence and (2) an approximately 6-fold increase in sensitivity of detection of peroxide and superoxide, as well as stabilizing the superoxide radical anion. The technique can also be used to evaluate the availability of antioxidants in biological homogenates and fluids. PMID:7804144

Trevithick, J R; Dzialoszynski, T

1994-08-01

242

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

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

243

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

PubMed Central

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. PMID:23758979

2013-01-01

244

Flow injection-photoinduced-chemiluminescence determination of ziram and zineb.  

PubMed

A simple, sensitive and rapid method for the determination of the pesticides ziram and zineb was described. This new method was based on the coupling of FIA methodology and direct chemiluminescent detection; this approach had not been used up to now with these pesticides. The additional use of an 'on line' photochemical reaction, which was performed by using a photoreactor consisting of a long piece of PTFE helically coiled around a 15W low-pressure lamp, increased by a factor >20 the chemiluminometric response of the pesticides. An additional 3-fold improvement in the analytical signal was also achieved by using quinine as sensitizer. The obtained throughputs were very high (121 and 101 h(-1) for ziram and zineb, respectively); this feature together with its low limit of detection (1 ng mL(-1)) makes this method particularly well suited to routine analyses of environmental samples. On the other hand, its applicability to two members of the dithiocarbamate family of pesticides, makes it promising for the determination of the rest of the members of this family. The method was demonstrated by application to spiked water samples from different origins (ground, river and irrigation). PMID:18724991

López Paz, J L; Catalá-Icardo, M

2008-09-12

245

Free Radical Production in Immune Cell Systems Induced by Ti, Ti6Al4V and SS Assessed by Chemiluminescence Probe Pholasin Assay  

PubMed Central

The oxidative burst of human blood cells in the presence of different metal materials was investigated using chemiluminescence assay. Commercial pure titanium (Ti), titanium alloy (Ti6Al4V), and stainless steel 316L (SS) in particulate form with <20??m in size were used. The effect of particulate materials opsonisation on the upregulation of the respiratory burst production by blood cells was also assessed. The largest chemiluminescence response was achieved after simultaneous injection of the stimulants fMLP+PMA. Moreover, Ti and SS induced a greater inflammatory reaction compared to Ti6Al4V, since the respiratory burst mounted was higher for both materials after opsonisation treatment. These results suggest that in vitro chemiluminescence response and respiratory burst measurements proved to be composition and treatment dependent. PMID:22778739

P. Cachinho, Sandra C.; Pu, Fanrong

2012-01-01

246

Chemiluminescence detection in liquid-core microstructured optical fibers  

Microsoft Academic Search

We reported the first measurement of chemiluminescence photon emission in microstructured optical fibers (MOFs). The hollow-core of a polymer MOF was infiltrated with fluid to support an index-guiding mechanism. The selective filling method involved sealing the cladding air-holes during polishing, leaving the hollow core available for the chemiluminescence solution. Experimental results, compared with a solid-core index-guiding fiber, indicated that the

Xia Yu; Khoi Seng Lok; Yien Chian Kwok; Ying Zhang; Huifeng Wei; Weijun Tong

247

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

SciTech Connect

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.

Lee-Chen, S.F.; Yu, C.T.; Wu, D.R. [Institute of Zoology, Taipei (Taiwan, Province of China)] [and others

1994-12-31

248

Prospects for the commercialization of chemiluminescence-based point-of-care and on-site testing devices.  

PubMed

Chemiluminescent reactions have found application in a number of commercial point-of-care and on-site testing devices. Notable examples include allergy tests (e.g., MASTpette, OPTIGEN® systems), flu tests (e.g., ZstatFlu®-II), cartridge-based immunoassay systems (FastPack® IP System, PATHFAST®), forensic tests for bloodstains, portable analyzers for biochip array assays (Evidence MultiStat), water quality tests (Eclox), air pollutants (e.g., oxides of nitrogen), and handheld devices for detecting explosives (e.g., E3500 Chemilux®). Many other point-of-care or on-site testing devices with a chemiluminescent end point have been devised on the basis of a variety of formats (e.g., cuvette, cassette, dipstick, test strip, microchip), but most have not progressed beyond a proof-of-principle or prototype stage. PMID:24658468

Park, Jason Y; Kricka, Larry J

2014-09-01

249

Urea Monitor Based on Chemiluminescence and Electrolysis as a Marker for Dialysis Efficiency  

NASA Astrophysics Data System (ADS)

We have developed a practical urea monitor based on a chemiluminescent (CL) reaction of urea and hypobromous acid produced by electrolysis of sodium bromide (NaBr) for measuring urea concentration in spent dialysate at set intervals. A reagent containing 4×10-2 M hypobromous acid is produced by electrolysis of an electrolyte containing 5.9 M NaBr and 0.2 M sodium hydroxide (NaOH). Chemiluminescence is emitted by injection of spent hemodialysis fluid (0.11 ml) into the reagent, and the CL-intensity is measured by a photomultiplier tube using the photon counting technique. The CL-intensity is proportional to the 0.9th power of the urea concentration between 7×10-4 and 2×10-2 M. The urea monitor can determine the urea concentration in spent dialysate samples collected from the waste line of a dialyzer, and the time for the intermittent measurements including the cleaning cycle of the reaction chamber is 3 min. The urea concentrations measured by the monitor are in close agreement with those measured by the conventional enzyme colorimetric method using urease for the spent dialysate collected during a hemodialysis treatment, and the correlation coefficient is 0.93.

Ozaki, Masahiro; Okabayashi, Tohru; Ishimaru, Teppei; Hayashi, Kunihito; Hori, Jun'ya; Yamamoto, Isao; Nakagawa, Masuo

250

[Chemiluminescence of whole saliva in antioxidant treatment of prosthetic bed tissues].  

PubMed

Inflammatory reaction is always accompanied by increased intensity of free-radical oxidation, especially when the phenomena of hypoxia and microcirculatory disorders that occur during the development of side-effects of acrylic removable dentures. This study determined the effectiveness of adaptogens, antioxidants in the complex treatment of diseases of tissues prosthetic field and their influence on the processes of LPO in whole mixed unstimulated saliva. Formed in the reaction to initiate the process of oxygen radicals (OH, RO, O(2)), initiate the formation of lipid peroxide radicals RO(2) biological substrate, the recombination of which leads to the emergence of unsustainable tetroxids, which decays with the release of light quanta. This luminescence is recorded as an amplified current of the photomultiplier, the registration systems. The results suggest the intensive formation of free radicals and peroxides in diseased tissue prosthetic field. Probably the main reason for increasing free-radical oxidation is the release of peroxidase from the crumbling inflammation, phagocytes (mainly neutrophils). The process of peroxidation contributes to an increase in blood supply to inflamed tissues, leading to local enrichment of oxygen, as well as toxic effects of acrylic bases of partial and complete removable dentures in the prosthetic field of tissue. Effect of antioxidants in combination with traditional treatment in 70 patients with periodontal disease and prosthetic bed was assessed by chemiluminescence analysis of whole mixed unstimulated saliva. The level of lipid peroxidation and chemiluminescence activity exceeded the normal values in the 1,5-2 - twice before the treatment. After treatment with antioxidants, these parameters decreased and increased during remission. Thus, studies to determine the status of saliva chemiluminescence method to treat and monitor the dynamics after treatment of periodontitis tissues supporting teeth prosthetic field in the control group and the main observation, revealed the following pattern: the approach of all the indices to normal in patients with a core group, which corresponded to the clinical dynamic index parameters of periodontal tissues supporting teeth prosthetic field, and a similar core group of the positive dynamics of the intensity values of chemiluminescence-indicators in the control group up to 3 months of observation, with a significant deterioration of the same indicators at a later time dynamic monitoring. PMID:20413812

Tunian, M Iu; Lalaian, B K; Zakarian, A E; Grigorian, K L; Pogosian, G A; Egiazarian, A V

2010-03-01

251

Real-time instrument for ambient monitoring of hydrogen sulfide, dimethyl sulfide, and other reduced organosulfur species using ozone chemiluminescent detection  

SciTech Connect

The chemiluminescent reactions of H/sup 2/S and other gaseous sulfides with ozone at 298/sup 0/K have been investigated, with the aim of developing a simple, selective, real-time monitor for these naturally emitted compounds. A commercial chemiluminescent ozone monitor has been adapted, for detection of the ozone/sulfide chemiluminescence between 300 and 400 nm wavelenght. Excess ozone was supplied to the reaction chamber from an electrical discharge ozone source. Response to dimethyl sulfide was enhanced by the use of air in the ozone source rather than oxygen. This effect was found to be caused by the presence of oxides of nitrogen produced in the ozonizer; a similar enhancement was not observed for the other sulfide compounds studied. Observed chemiluminescence signal decreased in the order CH/sub 3/SH > CH/sub 3/SCH/sub 3/ > H/sub 2/S > thiophene, with detection limits of 0.1, 0.3, 4, and 12 ppb respectively, at an instrument time constant of 60 sec. Calibration plots were linear at low sulfide concentrations, and showed less-than-first order dependence on sulfide at higher concentrations. A very small signal from ethylene was the only interference found from several compounds tested; sample air humidity has a small but significant effect on the instrument response.

Kelly, T.J.; Phillips, M.F.; Tanner, R.L.; Gaffney, J.S.

1982-01-01

252

In vitro and in vivo intraleukocytic accumulation of azithromycin (CP-62, 993) and its influence on ex vivo leukocyte chemiluminescence.  

PubMed Central

The accumulation of azithromycin in phagocytic cells was studied both in vitro by using a radiolabelled drug and a bioassay and in vivo for 12 volunteers receiving 1.5 g (total dose) orally within 3 days. In vitro, neutrophils and unfractionated blood leukocytes accumulated azithromycin up to 160-fold the extracellular concentration within 1 h at 37 degrees C but less than 3-fold at 4 degrees C. Dead cells accumulated up to 30-fold azithromycin, whereas NaF-treated cells accumulated up to 60-fold arithromycin. The mean efflux from preloaded cells was at most 31.0% +/- 10.6% (standard error of the mean) of the cell-associated concentration within 4 h of incubation at 37 degrees C in drug-free buffer. In vivo, the azithromycin concentration was 45.2 +/- 6.1 mg/liter of intracellular fluid at 2 h after the third dose and 36.6 +/- 8.3 mg/liter at 1 week thereafter. The corresponding concentrations in serum were 0.2 +/- 0.1 (2 h) and less than 0.05 (1 week). The luminol-enhanced chemiluminescence response induced by phorbol myristate acetate, opsonized zymosan, and two opsonized strains of Haemophilus influenzae (a type b capsulated strain and a noncapsulated strain) was also studied ex vivo by using the blood leukocytes from the 12 test volunteers and 4 control volunteers at 2 and 6 h after the third oral dose of azithromycin and at 2, 4, and 7 days thereafter. Azithromycin did not influence this response despite high levels of cellular accumulation. PMID:1329619

Bonnet, M; Van der Auwera, P

1992-01-01

253

Application of horse-radish peroxidase linked chemiluminescence to determine the production mechanism of Shiga-like toxins by E. coli O157:H7  

NASA Astrophysics Data System (ADS)

A sandwiched immunoassay consisting of toxin capture by immunomagnetic beads (IMB) and toxin detection by horseradish peroxidase (HRP) linked chemiluminescence was used to follow the production of Shiga-like toxins (SLT) by E. coli O157:H7. The intensity of luminescence generated by the oxidation of luminol-liked compounds was used to represent the concentration of toxins produced. The time-course of SLT production by E. coli O157:H7 under different conditions was investigated. In pure culture, optimal generation of SLT showed a significant delay than the steady state of cell growth. In mixed cultures of SLT producing E. coli O157:H7 and non-SLT producing E. coli K-12 strain, the production of toxins was substantially decreased. However, the growth of E. coli O157:H7 was not affected by the presence of K-12 strain. This decrease in SLT production was also observed in radiation-sterile ground beef. In regular ground beef that might contain numerous other bacteria, the growth of E. coli O157:H7 in EC media was not significantly affected but the lowered production of SLT was observed. The results showed that mechanism of inducing SLT production was complex with both the growth time and growth environment could influence SLT production. The addition of homo-serine lactone to the growth media enhanced the production of SLT. Thus, possibly cell-cell communication may have a role in SLT production by E. coli O157:H7.

Tu, Shu-I.; Uknalis, Joseph; Gehring, Andrew; He, Yiping

2007-09-01

254

Assessing problems of organic hydroperoxide-induced chemiluminescence related to biological/medical samples.  

PubMed

The supernatants obtained from mammalian tissue homogenates, blood serum or other body fluids, and supplemented with organic hydroperoxide show a multiplicity of light-emitting reactions. The low-level chemiluminescence of biological samples denotes that after hydroperoxide-induction electronically excited species are produced. The light-emission measured by photomultipliers is related to (i) the geometrical location of the induced sample, (ii) light gathering capacity of the phototubes, and (iii) both the quantity and concentration of samples and reactants. The fewest blood contamination of biological samples leads to an increased photoemission. The very high sensitivity of light detectors requires stable measuring and sampling conditions and peculiarly cautious evaluation of the reactions. PMID:15560941

Török, B

2004-10-29

255

Chemiluminescence detection of cannabinoids and related compounds with acidic potassium permanganate.  

PubMed

This is the first report of chemiluminescence from the reaction of cannabinoids with acidic potassium permanganate, which we have applied to the high performance liquid chromatography (HPLC) determination of cannabidiol (CBD) in industrial-grade hemp. The intensities of the light-producing reactions with two commercially available cannabinoid standards were compared to that of seven model phenolic analytes. Resorcinol, representing the parent phenolic moiety of the cannabinoid class, was shown to react with the permanganate reagents in a manner more similar to phenol than to its hydroxyphenol positional isomers, pyrocatechol and hydroquinone. Alkyl substituents on the phenolic ring, however, have a considerable impact on emission intensity that is dependent upon the position of the groups and the composition of the permanganate reagent. This analytical approach has potential for the determination of other cannabinoids including ?(9) -tetrahydrocannabinol in drug-grade cannabis. PMID:22461321

Holland, Brendan J; Francis, Paul S; Li, Bingshan; Tsuzuki, Takuya; Adcock, Jacqui L; Barnett, Neil W; Conlan, Xavier A

2012-01-01

256

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

PubMed Central

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

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

2014-01-01

257

Directional surface plasmon coupled chemiluminescence from nickel thin films: Fixed angle observation  

NASA Astrophysics Data System (ADS)

Directional surface plasmon coupled chemiluminescence (SPCC) from nickel thin films is demonstrated. Free-space and angular-dependent SPCC emission from blue, green and turquoise chemiluminescent solutions placed onto nickel thin films attached to a hemispherical prism were measured. SPCC emission was found to be highly directional and preferentially p-polarized, in contrast to the unpolarized and isotropic chemiluminescence emission. The largest SPCC emission for all chemiluminescence solutions was observed at a fixed observation angle of 60°, which was also predicted by theoretical Fresnel calculations. It was found that nickel thin films did not have a catalytic effect on chemiluminescence emission.

Weisenberg, Micah; Aslan, Kadir; Hortle, Elinor; Geddes, Chris D.

2009-04-01

258

Chemiluminescent evaluation of the human lacrimal outflow system.  

PubMed

A chemiluminescent material, Cyalume, has been used to demonstrate the structure and outflow patency of the human lacrimal drainage system. In this paper the details of this method are outlined and some of the possible benefits and limitations are discussed. Work is in progress to improve the techniques and to evaluate the toxicity of the chemiluminescent material in animals. It is hoped that these studies will lead to the development of a simple and rapid office procedure for assessing the structure and patency of the lacrimal tracts and simultaneously evaluating any obstruction. PMID:7470985

Raflo, G T; Hurwitz, J J

1981-01-01

259

Analyzer for measurement of nitrogen oxide concentration by ozone content reduction in gas using solid state chemiluminescent sensor  

NASA Astrophysics Data System (ADS)

Role of nitrogen oxide in ambient air is described and analyzed. New method of nitrogen oxide concentration measurement in gas phase is suggested based on ozone concentration measurement with titration by nitrogen oxide. Research of chemiluminescent sensor composition is carried out on experimental stand. The sensor produced on the base of solid state non-activated chemiluminescent composition is applied as ozone sensor. Composition is put on the surface of polymer matrix with developed surface. Sensor compositions includes gallic acid with addition of rodamine-6G. Model of interaction process between sensor composition and ozone has been developed, main products appeared during reaction are identified. The product determining the speed of luminescense appearance is found. This product belongs to quinone class. Then new structure of chemiluminescent composition was suggested, with absence of activation period and with high stability of operation. Experimental model of gas analyzer was constructed and operation algorithm was developed. It was demonstrated that developed NO measuring instrument would be applied for monitoring purposes of ambient air. This work was partially financially supported by Government of Russian Federation, Grant 074-U01

Chelibanov, V. P.; Ishanin, G. G.; Isaev, L. N.

2014-05-01

260

Feasibility of chemiluminescence as photodynamic therapy dosimetor  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) utilizes light energy of a proper wavelength to activate a pre-administered photosensitizer in a target tissue to achieve a localized treatment effect. Current treatment protocol of photodynamic therapy (PDT) is defined by empirical values such as irradiation light fluence, fluence rate and the amount of administered photosensitizer. It is well known that Singlet oxygen is the most important cytotoxic agent responsible for PDT biological effects. An in situ monitoring of singlet oxygen production during PDT would provide a more accurate dosimeter for PDT. The presented study has investigated the feasibility of using Fhioresceinyl Cypridina Luciferin Analog (FCLA), a singlet oxygen specific chemiluminescence (CL) probe, as a dosimetric tool for PDT. Raji lymphoma cell suspensions were sensitized with Photofrin (R) of various concentrations and irradiated with 635 nm laser light at different fluence rates. FCLA-CL from singlet oxygen produced by the treatment was measured, in real time, with a photon multiplier tube (PMT) system, and linked to the cytotoxicity resulting from the treatment. We have observed that the CL intensity of FCLA is dependent on the PDT treatment parameters. After each PDT treatment and CL measurement, the irradiated cells were evaluated by MIT assay for their Viability. The results show that the cell viability is highly related to the accumulated CL. With 10 II quencher, we confirmed that the CL was mainly related to PDT produced 10 II The results suggest that the FCLA-CL system can be an effective means in measuring PDT 1O II production and may provide an alternative dosimetry technique for PDT.

Qin, Yanfang; Xing, Da; Zhong, Xueyun; Zhou, Jin; Luo, Shiming; Chen, Qun

2006-09-01

261

High throughput heme assay by detection of chemiluminescence of reconstituted horseradish peroxidase.  

PubMed

In living organisms, heme is an essential molecule for various biological functions. Recent studies also suggest that heme functions as organelle-derived signal that regulates fundamental cell processes. Furthermore, estimation of heme is widely used for studying various blood disorders. In this regard, development of a rapid, sensitive, and high throughput heme assay has been sought. The most frequently used method of measuring heme by pyridine hemochrome is time, labor, and material intensive, and therefore limiting in its utility for large scale, high throughput analysis. Recently, we reported alternative method that is sensitive and specific to heme, which is based on the ability of horseradish peroxidase (HRP) apo-enzyme to reconstitute with heme to form an active holo-enzyme. Here, we developed high throughput heme assay by performing reactions on multi-well plate with highly sensitive chemiluminescence detection reagents. Detection of chemiluminescence in charged coupled device (CCD)-based gel doc apparatus enables simultaneous measurement of multiple samples. Furthermore, the high sensitivity of this assay allowed a direct measurement of heme in solvent extracts after dilution. This assay is sensitive, quick, provides a large dynamic range, and is well suited for large-scale analysis of heme extracted from minute amount of samples. PMID:19519333

Takahashi, Shigekazu; Masuda, Tatsuru

2009-06-01

262

Determination of oxides of nitrogen (NO/sub x/) in cigarette smoke by chemiluminescent analysis  

SciTech Connect

The successful application of a commercial chemiluminescent No/sub x/ analyzer to the determination of oxides of nitrogen in cigarette smoke is reported. Individual puffs of the smoke vapor phase are rapidly diluted in an air stream before introduction into the analyzer. This acts to both reduce quenching of the chemiluminescent response by CO/sub 2/ and to prevent side reactions of the NO/sub x/ with vapor phase organic constituents. Sweeping the dilute smoke through a reduced silver-ion exchange resin bed removed a substantial positive interference from hydrogen cyanide. A range of deliveries of 3 to 47 ..mu..mol of NO/sub x/ per cigarette was observed for nine types of experimental cigarettes. Statistically significant differences between NO/sub x/ and NO levels (NO/sub x/ - NO = NO/sub 2/) in smoke were observed in only one type of cigarette, presumably due to large cigarette-to-cigarette variability in constituent deliveries. 2 figures, 3 tables.

Jenkins, R.A.; Gill, B.E.

1980-05-01

263

Intensification of the electrochemiluminescence of luminol on hollow TiO? nanoshell-modified indium tin oxide electrodes.  

PubMed

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. PMID:25059155

Hong, Jia; Ming, Liang; Tu, Yifeng

2014-10-01

264

Photoluminescence, chemiluminescence and anodic electrochemiluminescence of hydrazide-modified graphene quantum dots  

NASA Astrophysics Data System (ADS)

Single-layer graphene quantum dots (SGQDs) were refluxed with hydrazine (N2H4) to prepare hydrazide-modified SGQDs (HM-SGQDs). Compared with SGQDs, partial oxygen-containing groups have been removed from HM-SGQDs. At the same time, a lot of hydrazide groups have been introduced into HM-SGQDs. The introduced hydrazide groups provide HM-SGQDs with a new kind of surface state, and give HM-SGQDs unique photoluminescence (PL) properties such as blue-shifted PL emission and a relatively high PL quantum yield. More importantly, the hydrazide-modification made HM-SGQDs have abundant luminol-like units. Accordingly, HM-SGQDs exhibit unique and excellent chemiluminescence (CL) and anodic electrochemiluminescence (ECL). The hydrazide groups of HM-SGQDs can be chemically oxidized by the dissolved oxygen (O2) in alkaline solutions, producing a strong CL signal. The CL intensity is mainly dependent on the pH value and the concentration of O2, implying the potential applications of HM-SGQDs in pH and O2 sensors. The hydrazide groups of HM-SGQDs can also be electrochemically oxidized in alkaline solutions, producing a strong anodic ECL signal. The ECL intensity can be enhanced sensitively by hydrogen peroxide (H2O2). The enhanced ECL intensity is proportional to the concentration of H2O2 in a wide range of 3 ?M to 500 ?M. The detection limit of H2O2 was calculated to be about 0.7 ?M. The results suggest the great potential applications of HM-SGQDs in the sensors of H2O2 and bio-molecules that are able to produce H2O2 in the presence of enzymes.Single-layer graphene quantum dots (SGQDs) were refluxed with hydrazine (N2H4) to prepare hydrazide-modified SGQDs (HM-SGQDs). Compared with SGQDs, partial oxygen-containing groups have been removed from HM-SGQDs. At the same time, a lot of hydrazide groups have been introduced into HM-SGQDs. The introduced hydrazide groups provide HM-SGQDs with a new kind of surface state, and give HM-SGQDs unique photoluminescence (PL) properties such as blue-shifted PL emission and a relatively high PL quantum yield. More importantly, the hydrazide-modification made HM-SGQDs have abundant luminol-like units. Accordingly, HM-SGQDs exhibit unique and excellent chemiluminescence (CL) and anodic electrochemiluminescence (ECL). The hydrazide groups of HM-SGQDs can be chemically oxidized by the dissolved oxygen (O2) in alkaline solutions, producing a strong CL signal. The CL intensity is mainly dependent on the pH value and the concentration of O2, implying the potential applications of HM-SGQDs in pH and O2 sensors. The hydrazide groups of HM-SGQDs can also be electrochemically oxidized in alkaline solutions, producing a strong anodic ECL signal. The ECL intensity can be enhanced sensitively by hydrogen peroxide (H2O2). The enhanced ECL intensity is proportional to the concentration of H2O2 in a wide range of 3 ?M to 500 ?M. The detection limit of H2O2 was calculated to be about 0.7 ?M. The results suggest the great potential applications of HM-SGQDs in the sensors of H2O2 and bio-molecules that are able to produce H2O2 in the presence of enzymes. Electronic supplementary information (ESI) available: AFM images of SGQDs and HM-SGQDs (Fig. S1), FT-IR spectra of SGQDs and HM-SGQDs (Fig. S2), UV-vis and PL emission spectra of R-SGQDs (Fig. S3), cathodic ECL responses of SGQD, R-SGQDs and HM-SGQDs (Fig. S4), and the pH effect on the anodic ECL responses of HM-SGQDs (Fig. S5). See DOI: 10.1039/c4nr02539c

Dong, Yongqiang; Dai, Ruiping; Dong, Tongqing; Chi, Yuwu; Chen, Guonan

2014-09-01

265

Low-Level Chemiluminescence and Life Span of Drosophila melanogaster  

Microsoft Academic Search

Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30°C for 5 days after emergence was measured. When maintained at 30°C the fly CL intensity was stronger than at 25°C. Under the condition of the higher temperature, the fly life span was shorter (mean life span =

Tomoko Sato; Teruo Miyazawa; Masaki Kobayashi; Hideyuki Furukawa; Humio Inaba

1992-01-01

266

TECHNICAL ASSISTANCE DOCUMENT FOR THE CHEMILUMINESCENCE MEASUREMENT OF NITROGEN DIOXIDE  

EPA Science Inventory

Gas phase chemiluminescence has been designated as the reference measurement principle for the measurement of nitrogen dioxide (NO2) in the ambient atmosphere. Continuous analyzers based on this measurement principle may be calibrated with NO2 either from the gas phase titration ...

267

Chemiluminescent detection of RFLP patterns in forensic DNA analysis.  

PubMed

DNA testing by restriction fragment length polymorphism (RFLP) analysis is an extremely important technique used in forensic science laboratories. While RFLP testing is a highly informative method, it traditionally has had several disadvantages. It is time consuming and involves work with radioactive phosphorous. A detection method that is faster and safer than isotopic detection is presented. Various membranes, fixation methods and transfer procedures were evaluated for DNA retention and sensitivity using alkaline phosphatase conjugated oligonucleotide probes and a chemiluminescent substrate. Blood samples and evidentiary material from forensic casework were analyzed by both chemiluminescent and isotopic detection. Results of each method were compared for pattern appearance, band size, and composite profile frequency. The chemiluminescent system had very good sensitivity, detecting 3-25 ng K562 DNA. Most patterns developed by both methods appeared the same. The variation observed between band sizes and frequency estimates generated by each method was as expected for an inter-gel comparison. The chemiluminescent detection procedure described here is suitable for use in forensic casework. PMID:8754566

Johnson, E D; Kotowski, T M

1996-07-01

268

A new chemiluminescence method for determination of clonazepam and diazepam based on 1-Ethyl-3-Methylimidazolium Ethylsulfate/copper as catalyst  

NASA Astrophysics Data System (ADS)

A novel chemiluminescence (CL) reaction, Benzodiazepines-H2O2-1-Ethyl-3-Methylimidazolium Ethylsulfate/copper, for determination of clonazepam and diazepam at nanogram per milliliter level in batch-type system have been described. The method relies on the catalytic effect of 1-Ethyl-3-Methylimidazolium Ethylsulfate/copper on the chemiluminescence reaction of Benzodiazepines, the oxidation of Benzodiazepines with hydrogen peroxide in natural medium. The influences of various experimental parameters such as solution pH, the ratio of 1-Ethyl-3 Methylimidazolium ethylsulfate concentration to copper ion, the type of buffer and the concentration of CL reagents were investigated. Under the optimum condition, the proposed method was satisfactorily applied for the determination of these drugs in tablets and urine without the interference of their potential impurities.

Chaichi, M. J.; Alijanpour, S. O.

2014-01-01

269

Peroxyoxalate chemiluminescence enhanced by oligophenylenevinylene fluorophores in the presence of various surfactants.  

PubMed

The effect of several surfactants on peroxyoxalate chemiluminescence (PO-CL) using oligophenylenevinylene fluorophores was investigated. Among several oligophenylenevinylenes consisting of stilbene units, linearly conjugated ones, such as distyrylbenzene and distyrylstilbene, effectively enhanced PO-CL efficiency. Various effects of anionic, cationic, amphoteric and non-ionic surfactants on the CL efficiency of PO-CL were determined using three oxalates and the distyrylbenzene fluorophore. Anionic and non-ionic surfactants effectively enhanced CL efficiency, in contrast to the negative effect of cationic and amphoteric surfactants. Non-ionic surfactants were also effective in CL reactions of oxalates bearing dodecyl ester groups by the hydrophobic interaction between their alkyl chains. Considering these results, the surfactants not only increase the concentrations of water-insoluble interacting species in the hydrophobic micelle cores, but also control rapid degradation of the oxalates by alkaline hydrolysis. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24425305

Motoyoshiya, Jiro; Takigawa, Setsuko

2014-11-01

270

Simultaneous detection of single attoliter droplet collisions by electrochemical and electrogenerated chemiluminescent responses.  

PubMed

We provide evidence of single attoliter oil droplet collisions at the surface of an ultra-microelectrode (UME) by the observation of simultaneous electrochemical current transients (i-t curves) and electrogenerated chemiluminescent (ECL) transients in an oil/water emulsion. An emulsion system based on droplets of toluene and tri-n-propylamine (2:1 v/v) emulsified with an ionic liquid and suspended in an aqueous continuous phase was formed by ultrasonification. When an ECL luminophore, such as rubrene, is added to the emulsion droplet, stochastic events can be tracked by observing both the current blips from oxidation at the electrode surface and the ECL blips from the follow-up ECL reaction, which produces light. This report provides a means of studying fundamental aspects of electrochemistry using the attoliter oil droplet and offers complementary analytical techniques for analyzing discrete collision events, size distribution of emulsion systems, and individual droplet electroactivity. PMID:25213468

Dick, Jeffrey E; Renault, Christophe; Kim, Byung-Kwon; Bard, Allen J

2014-10-27

271

Electrogenerated chemiluminescence behavior of peptide nanovesicle and its application in sensing dopamine.  

PubMed

The electrogenerated chemiluminescence (ECL) behavior of the bioinspired peptide nanovesicles (PNVs) was reported for the first time. The PNVs modified glassy carbon electrodes have shown a stable and efficient cathodic ECL signal with K2S2O8 as coreactant in aqueous solution. The possible ECL reaction mechanism was proposed. Dopamine (DA) was chosen as a model analyte to study the potential of the PNVs in the ECL analytical application. It was found that the ECL intensity of the PNVs was effectively increased by trace amounts of DA. The limit of detection was estimated to be 3.15pM (S/N=3). These results suggest that the PNVs could be a new class of promising materials for the ECL design and bioassays in the future due to their fascinating features, such as excellent biocompatibility, tunable composition as well as capability of molecular recognition. PMID:25129510

Huang, Chunxiu; Chen, Xu; Lu, Yanluo; Yang, Hui; Yang, Wensheng

2015-01-15

272

Scanning laser vibrometry and luminol photomicrography to map cavitational activity around ultrasonic scalers  

NASA Astrophysics Data System (ADS)

Ultrasonic dental scalers are clinically used to remove deposits from tooth surfaces. A metal probe, oscillating at ultrasonic frequencies, is used to chip away deposits from the teeth. To reduce frictional heating, water flows over the operated probe in which a bi-product, cavitation, may be generated. The aim of this study is characterise probe oscillations using scanning laser vibrometry and to relate the recorded data to the occurrence of cavitation that is mapped in the course of this research. Scanning laser vibrometry (Polytec models 300-F/S and 400-3D) was used to measure the movement of various designs of operating probes and to locate vibration nodes / anti-nodes at different generator power settings and contact loads (100g and 200g). Cavitation mapping was performed by photographing the emission from a luminol solution with a digital camera (Artemis ICX285). The scaler design influences the number and location of vibration node / anti-node points. For all ultrasonic probes, the highest displacement amplitude values were recorded at the tip. The highest amounts of cavitation around the probes were recorded at the second anti-node measured from the tip. Broad, beaver-tale shaped probes produced more cavitation than slim shaped ones. The design also influences the amount of inertial cavitation around the operated instrument. The clinical relevance is that broad, beaver-tale shaped probes are unlikely to reach subgingival areas of the tooth. Further research is required to design probes that will be clinically superior to cleaning this area of the tooth.

Felver, Bernhard; King, David C.; Lea, Simon C.; Price, Gareth J.; Walmsley, A. Damien

2008-06-01

273

Signal-on dual-potential electrochemiluminescence based on luminol-gold bifunctional nanoparticles for telomerase detection.  

PubMed

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 (?ECL(Luminol)/?ECL(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. PMID:24646287

Zhang, Huai-Rong; Wu, Mei-Sheng; Xu, Jing-Juan; Chen, Hong-Yuan

2014-04-15

274

Chemiluminescent substrates for detection of restriction fragment length polymorphism.  

PubMed

Five new enzyme-triggered dioxetane substrates were evaluated for restriction fragment length polymorphism (RFLP) analysis of HaeIII- restricted DNA. Of these, one substrate designated CDP-Star provided unsurpassed sensitivity within one working day without the presence of an enhancer. Far greater sensitivity was obtained from chemiluminescent detection of DNA on MSI neutral membranes than the sensitivity obtained from six day film exposures of 32P labelled insert probes on PALL B membranes, including the detection of most low molecular weight alleles. For nylon membranes better suited for alkaline phosphatase-triggered chemiluminescent detection of DNA, high salt/neutral pH southern transfer conditions were better than alkaline southern transfer conditions. PMID:8921749

Price, D C

1996-01-01

275

Quantitation method of N,N '-disalicylidene-1,2-propanediamine by comprehensive two-dimensional gas chromatography coupled to a nitrogen chemiluminescence detector.  

PubMed

Metal deactivator additives (MDAs) have been used for over 60 years to prevent metal catalyzed reactions in petroleum products; a commonly used metal deactivator is N,N'-disalicylidene-1,2-propanediamine. The quantitation of low MDA concentrations in fuels is challenging due to the complexity of the sample matrix. In this work, this difficulty was overcome using GC × GC hyphenated with a nitrogen chemiluminescence detector. The high resolution power of GC × GC avoided co-elution between the MDA and other sample matrix compounds; while the enhanced sensitivity of GC × GC and the use of a nitrogen chemiluminescence detector supplied a high sensitivity and specificity for nitrogen compounds. For the analysis, the MDA additive was derivatized with the silylation agent N,O-bis (trimethylsilyl)trifluoroacetamide at room temperature and its quantitation was based on an external calibration curve; good linear response was obtained in the 1.4-8.6 ppm range. PMID:23494992

Lissitsyna, Kristina; Huertas, Sonia; Quintero, Luis Carlos; Polo, Luis Maria

2013-06-01

276

Chemiluminescence-based multivariate sensing of local equivalence ratios in premixed atmospheric methane-air flames  

SciTech Connect

Chemiluminescence emissions from OH*, CH*, C2, and CO2 formed within the reaction zone of premixed flames depend upon the fuel-air equivalence ratio in the burning mixture. In the present paper, a new partial least square regression (PLS-R) based multivariate sensing methodology is investigated and compared with an OH*/CH* intensity ratio-based calibration model for sensing equivalence ratio in atmospheric methane-air premixed flames. Five replications of spectral data at nine different equivalence ratios ranging from 0.73 to 1.48 were used in the calibration of both models. During model development, the PLS-R model was initially validated with the calibration data set using the leave-one-out cross validation technique. Since the PLS-R model used the entire raw spectral intensities, it did not need the nonlinear background subtraction of CO2 emission that is required for typical OH*/CH* intensity ratio calibrations. An unbiased spectral data set (not used in the PLS-R model development), for 28 different equivalence ratio conditions ranging from 0.71 to 1.67, was used to predict equivalence ratios using the PLS-R and the intensity ratio calibration models. It was found that the equivalence ratios predicted with the PLS-R based multivariate calibration model matched the experimentally measured equivalence ratios within 7%; whereas, the OH*/CH* intensity ratio calibration grossly underpredicted equivalence ratios in comparison to measured equivalence ratios, especially under rich conditions ( > 1.2). The practical implications of the chemiluminescence-based multivariate equivalence ratio sensing methodology are also discussed.

Tripathi, Markandey M.; Krishnan, Sundar R.; Srinivasan, Kalyan K.; Yueh, Fang-Yu; Singh, Jagdish P.

2012-03-01

277

Investigation on the spontaneous combustion of refuse-derived fuels during storage using a chemiluminescence technique.  

PubMed

Refuse-derived fuel (RDF), a high-caloric material, is used by various combustion processes, such as power plants, as alternative fuel. Several explosion accidents, however, possibly initiated by the spontaneous combustion of stored RDF, have been reported in Japan. Therefore the spontaneous combustion of RDF prepared from domestic garbage was investigated using chemiluminescence. RDF samples were heated either under air or under nitrogen for 1, 2, or 4 h at 120 or 140 degrees C and then cooled by an air or nitrogen stream. All RDF samples exhibited chemiluminescence. In air-treated RDF samples (heated and cooled by air), chemiluminescence after ageing was shown to be slightly lower than before ageing, whereas in nitrogen-treated samples (both heated and cooled by nitrogen) chemiluminescence decreased significantly after ageing. When nitrogen was replaced with air during aging, however, a sudden increase of chemiluminescence was observed. On the other hand, when cooling was done with air, chemiluminescence increased. Higher chemiluminescence was also observed during high-temperature treatment. Further experiments on cellulose, one of the major components of domestic garbage, exhibited similar chemiluminescence patterns to those of RDF when treated by the same methods as those used for RDF ageing. Chemiluminescence from cellulose increased significantly when the atmospheric gas was changed from nitrogen to air, suggesting that oxygen in the air promoted the formation of hydroperoxide from cellulose. Therefore, it is hypothesized that cellulose plays an important role in the formation of chemiluminescence from RDF. The formation of chemiluminescence indicated that radicals are formed from RDF by oxidation or thermal degradation at room or atmospheric temperatures and may subsequently lead to spontaneous combustion. PMID:19039070

Matunaga, Atsushi; Yasuhara, Akio; Shimizu, Yoshitada; Wakakura, Masahide; Shibamoto, Takayuki

2008-12-01

278

A novel selenium nanoparticles-enhanced chemiluminescence system for determination of dinitrobutylphenol.  

PubMed

A novel selenium nanoparticles (Se NPs)-amplified chemiluminescence (CL) reaction, Se NPs-potassium permanganate-dinitrobutylphenol (DNBP), for the determination of DNBP at gram per milliliter level is described. In the present study, it was found that direct reaction of DNBP with potassium permanganate (KMnO4) in the acidic mediums elicited light emission, which was greatly enhanced by selenium nanoparticles. Under optimum conditions, the CL intensity is linearly related to the concentration of DNBP in the range of 1.0×10(-7)-8.0×10(-5)g mL(-1) with a detection limit (3?) of 3.1×10(-8) g mL(-1). The relative standard deviation for 11 determinations of 2.5×10(-5) gm L(-1) DNBP is 2.07%. The Se NPs were prepared by the chemical hydrothermal method. It was found that catalytic properties of Se NPs were higher than those of microparticles (MPs). In addition, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the Se NPs. Appropriate sensitivity, selectivity and precision were among notable features of the proposed method. The method was successfully applied to the determination of DNBP in the water samples of different origins. Moreover, the possible mechanism for the new CL reaction was also discussed. PMID:23598221

Iranifam, M; Fathinia, M; Sadeghi Rad, T; Hanifehpour, Y; Khataee, A R; Joo, S W

2013-03-30

279

Time-resolved chemiluminescence strategy for multiplexed immunoassay of clenbuterol and ractopamine.  

PubMed

A novel time-resolved chemiluminescence (CL) strategy was proposed for immunoassay of multiple analytes in a single run. The strategy was performed based on the distinction of the kinetic characteristics of different CL reaction systems, which allowed detection of multiple analytes in different time windows. The strategy was evaluated by using clenbuterol and ractopamine as the model analytes. Horseradish peroxidase (HRP) and alkaline phosphatase (ALP) were adopted as the signal probes to tag the two antigens due to their very different CL kinetic characteristics. After the competitive immunoreactions, the two CL signals were simultaneously triggered by adding the CL coreactants. Then the signals for clenbuterol and ractopamine were in turn detected after 0.6 s and 25 min of the reaction triggering. Due to the distinguishable detection time windows for HRP and ALP, the cross-talk resulting from the mixed CL reaction systems was effectively avoided, which was frequently encountered in some other multiplexed immunoassays based on multi-label modes. The linear ranges for clenbuterol and ractopamine were both 1.0-500 ng/mL, with detection limits of 0.50 ng/mL (S/N=2). The results for real sample analysis demonstrated that this study could provide a simple, low-cost and fast approach toward multiplexed immunoassay. PMID:23644144

Han, Jing; Gao, Hongfei; Wang, Wenwen; Wang, Zhenxing; Fu, Zhifeng

2013-10-15

280

Chemiluminescence and superoxide anion production by leukocytes from chronic hemodialysis patients  

Microsoft Academic Search

Chemiluminescence and superoxide anion production by leukocytes from chronic hemodialysis patients. During phagocytosis or in response to a soluble stimulus, polymorphonuclear leukocytes (PMN) undergo a burst of oxidative metabolism involved intimately in antimicrobial activity. Superoxide anion produced during the burst is bactericidal either directly or as an intermediate metabolite. In addition, stimulated PMN's emit light or chemiluminescence (CL). CL is

Elizabeth E Ritchey; John D Wallin; Sudhir V Shah

1981-01-01

281

On use of CO 2 ? chemiluminescence for combustion metrics in natural gas fired reciprocating engines  

Microsoft Academic Search

Flame chemiluminescence is widely acknowledged to be an indicator of heat release rate in premixed turbulent flames that are representative of gas turbine combustion. Though heat release rate is an important metric for evaluating combustion strategies in reciprocating engine systems, its correlation with flame chemiluminescence is not well studied. To address this gap an experimental study was carried out in

Sreenath B. Gupta; Bipin P. Bihari; Munidhar S. Biruduganti; Raj R. Sekar; James Zigan

2011-01-01

282

A novel chemiluminescent ELISA for detecting furaltadone metabolite, 3-amino-5-morpholinomethyl-2-oxazolidone (AMOZ) in fish, egg, honey and shrimp samples.  

PubMed

In this study, an indirect competitive enzyme-linked immunosorbent assay with chemiluminescent (CLELISA) detection for 3-amino-5-morpholinomethyl-2-oxazolidone (AMOZ) was developed. A monoclonal antibody (MAb) against AMOZ was prepared through immunizing BALB/c mice with 4-carboxybenzaldehyle derivatized AMOZ (CPAMOZ), conjugated with bovine serum albumin (BSA) as antigen. The effects of the substrates luminol, p-iodophenol and urea peroxide on the performance of the assay were studied and optimized. In addition, the specificity of the MAb, estimated as the cross-reactivity values with 4-nitrobenzaldehyde derivatized AMOZ (NPAMOZ), CPAMOZ and AMOZ, was 100%, 27.45% and 0.18%, respectively. The sensitivity of the developed CLELISA was estimated as 50% inhibitory concentration (IC50) value (0.14?g/l) with a linear working range between 0.03 and 64?g/l, and a limit of detection of 0.01?g/l. The CLELISA described in this study was 5-fold more sensitive than the indirect competitive ELISA previously developed in our laboratory. Finally, this new CLELISA was compared with a commercial kit to detect NPAMOZ in spiked fish, shrimp, honey and egg samples. The recovery values from four spiked fish, shrimp, honey and egg samples with different concentrations of NPAMOZ in CLELISA were 92.1-107.7%. Thus, the immunoassay method described here has a broad detection range and high sensitivity and is a valid and cost-effective means for high throughput monitoring of residual AMOZ levels in fish, shrimps, honey and eggs with potential applications in other animal tissues. PMID:23810835

Liu, Ying-Chun; Jiang, Wei; Chen, Yong-Jun; Xiao, Yan; Shi, Jin-Lei; Qiao, Yuan-Biao; Zhang, Hua-Jing; Li, Tao; Wang, Quan

2013-09-30

283

Crystallochemiluminescence of solutions  

NASA Astrophysics Data System (ADS)

It is shown that the chemiluminescence intensity from luminol solutions reaches a maximum when the latter are crystallized. This phenomenon is explained by the complex dynamics of the phase transition, chemical reactions, and degradation of electronic excitation energy. Luminescence of new type, called crystallochemiluminescence, is revealed.

Gus'kov, A. P.; Nekrasova, L. P.; Gornakova, A. S.; Shikunova, I. A.

2014-09-01

284

Selective determination of acenaphthylene by flow injection analysis with tris(2,2'-bipyridine)ruthenium(II) chemiluminescence detection.  

PubMed

A simple, rapid flow injection chemiluminescence (FI-CL) method has been developed for selective determination of acenaphthylene (ACY), based on the CL produced in the reaction of tris(2,2'-bipyridine)ruthenium(III) (Ru(bipy)3(3+)) and ACY in an acidic buffer solution. Under the optimum experimental conditions, the calibration curve was linear over the range 5.0 x 10(-3) to 4.0 x 10(-7) mol L(-1) for ACY. The detection limit (S/N=3) was 2.0 x 10(-7)mol L(-1) and the relative standard deviation of 10 replicate measurements was 2.3% for 5.0 x 10(-5)mol L(-1) of ACY. Selectivity of CL reaction of ACY from other 15 polycyclic aromatic hydrocarbons (PAHs) was investigated by flow injection method. The method was applied to determine the ACY content in soil. PMID:18371639

Li, Ming; Lee, Sang Hak

2007-11-30

285

OH* Chemiluminescence: Pressure Dependence of O + H + M = OH* + M  

E-print Network

. 1352?1356. [17] Smith, G. P.; Luque, J.; Park, C.; Jeffries, J. B.; and Crosley, D. R. "Low Pressure Flame Determinations of Rate Constants for OH(A) and CH(A) Chemiluminescence," Combustion and Flame, Vol. 131, No. 1 ? 2, 2002, pp. 59-69. [18.... ?Experimental and Computational Study of CH, CH*, and OH* in an Axisymmetric Laminar Diffusion Flame,? Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998, pp. 615-623. [20] Luque, J.; Jeffries, J. B.; Smith, G. P.; Crosley...

Donato, Nicole

2011-02-22

286

Electrogenerated chemiluminescence immunosensor for Bacillus thuringiensis Cry1Ac based on Fe3O4@Au nanoparticles.  

PubMed

A highly sensitive electrochemiluminescence (ECL) immunosensor for Cry1Ac was fabricated. The primary antibody anti-Cry1Ac was immobilized onto core-shell structural Fe(3)O(4)@Au nanoparticles. The antigen and glucose-oxidase-labeled secondary antibody were then successively combined to form sandwich-type immunocomplexes through a specific interaction. The magnetic particles loaded with sandwich immune complexes were attracted to a magnet-controlled glass carbon electrode (GCE) by an external magnet applied on top of the GCE. ECL was generated by the reaction between luminol and hydrogen peroxide derived from the enzymatic reaction in the presence of glucose. The sensors exhibited high sensitivity and a wide linear range for Bacillus thuringiensis Cry1Ac detection from 0 to 6 ng/mL, as well as a detection limit of 0.25 pg/mL (S/N = 3). The sensor is one of the most sensitive sensors for Cry1Ac, which can be easily renewed and conveniently used. PMID:23317307

Li, Jianping; Xu, Qian; Wei, Xiaoping; Hao, Zaibin

2013-02-20

287

Evaluation of Single Column Trapping/Separation and Chemiluminescence Detection for Measurement of Methanethiol and Dimethyl Sulfide from Pig Production  

PubMed Central

Reduced sulfur compounds are considered to be important odorants from pig production due to their low odor threshold values and low solubility in slurry. The objective of the present study was to investigate the use of a portable method with a single silica gel column for trapping/separation coupled with chemiluminescence detection (SCTS-CL) for measurement of methanethiol and dimethyl sulfide in sample air from pig production. Proton-transfer-reaction mass spectrometry (PTR-MS) was used to evaluate the trapping/separation. The silica gel column used for the SCTS-CL efficiently collected hydrogen sulfide, methanethiol and dimethyl sulfide. The measurement of methanethiol by SCTS-CL was clearly interfered by the high concentration of hydrogen sulfide found in pig production, and a removal of hydrogen sulfide was necessary to obtain reliable results. Air samples taken from a facility with growing-finishing pigs were analyzed by SCTS-CL, PTR-MS, and a gas chromatograph with sulfur chemiluminescence detection (GC-SCD) to evaluate the SCTS-CL. The difference between the concentrations of methanethiol and dimethyl sulfide measured with SCTS-CL, PTR-MS, and GC-SCD was below 10%. In conclusion, the SCTS-CL is a portable and low-cost alternative to the commercial methods that can be used to measure methanethiol and dimethyl sulfide in sample air from pig production. PMID:22997603

Hansen, Michael J?rgen; Toda, Kei; Obata, Tomoaki; Adamsen, Anders Peter S.; Feilberg, Anders

2012-01-01

288

Selective activity of butyrylcholinesterase in serum by a chemiluminescent assay.  

PubMed

In a previous study, we showed that purified commercial esterase activity can be detected in a chemiluminescent assay based on the hydrolysis of 2-methyl-1-propenylbenzoate (MPB) to 2-methyl-1-propenol, which is subsequently oxidized by the horseradish peroxidase (HRP)-H(2)O(2) system. The purpose of this study was to verify the applicability of this assay to human serum. The existence of an esterase activity capable of hydrolysing MPB is indicated by the fact that the MPB-serum-HRP-H(2)O(2) system consumes oxygen and emits light. Both signals were abolished by prior serum heat inactivation and were preserved when serum was stored at < or =4 degrees C. Addition of aliesterase inhibitors, such as fluoride ion and trichlorfon or the cholinesterase inhibitor eserine, totally prevents light emission. The butyrylcholinesterase-specific substrate benzoylcholine causes a delay in both O(2) uptake and light emission, while the specific acetylcholinesterase substrate, acetyl-beta-methylcholine, had practically no effect. Purified butyrylcholinesterase, but not acetylcholinesterase, triggered light emission. The finding that butyrylcholinesterase is responsible for the hydrolysis of MPB in serum should serve as the basis for the development of a specific chemiluminescent assay for this enzyme. PMID:11590700

Yavo, B; Brunetti, I L; da Fonseca, L M; Catalani, L H; Campa, A

2001-01-01

289

Method for detecting pollutants. [through chemical reactions and heat treatment  

NASA Technical Reports Server (NTRS)

A method is described for detecting and measuring trace amounts of pollutants of the group consisting of ozone, nitrogen dioxide, and carbon monoxide in a gaseous environment. A sample organic solid material that will undergo a chemical reaction with the test pollutant is exposed to the test environment and thereafter, when heated in the temperature range of 100-200 C., undergoes chemiluminescence that is measured and recorded as a function of concentration of the test pollutant. The chemiluminescence of the solid organic material is specific to the pollutant being tested.

Rogowski, R. S.; Richards, R. R.; Conway, E. J. (inventors)

1976-01-01

290

Enhancement of the chemiluminescence of permanganate-formaldehyde system by gold\\/silver nanoalloys and its application to trace determination of melamine  

Microsoft Academic Search

Gold\\/silver alloy nanoparticles (Au\\/Ag NPs) are shown to exert a beneficial effect on the chemiluminescence (CL) reaction\\u000a of permanganate-formaldehyde in the presence of sodium dodecyl sulfate micelles. The Au\\/Ag NPs can be prepared by chemical\\u000a reduction and display better catalytic properties than their monometallic counterparts. Transmission electron microscopy,\\u000a energy dispersion X-ray spectrometry and UV–vis spectroscopy were used to characterize the

Jamshid L. Manzoori; Mohammad Amjadi; Javad Hassanzadeh

291

Feasibility study for rocket ozone measurements in the 50 to 80 km region using a chemiluminescent technique  

NASA Technical Reports Server (NTRS)

A study has been conducted to determine the feasibility of increasing sensitivity for ozone detection. The detection technique employed is the chemiluminescent reaction of ozone with a rhodamine-B impregnated disk. Previously achieved sensitivities are required to be increased by a factor of about 20 to permit measurements at altitudes of 80 km. Sensitivity was increased by using a more sensitive photomultiplier tube, by increasing the gas velocity past the disk, by different disk preparation techniques, and by using reflective coatings in the disk chamber and on the uncoated side of the glass disk. Reflective coatings provided the largest sensitivity increase. The sum of all these changes was a sensitivity increased by an estimated factor of 70, more than sufficient to permit measurement of ambient ozone concentrations at altitudes of 80 km.

Goodman, P.

1973-01-01

292

Electrogenerated chemiluminescence of BODIPY, Ru(bpy)3(2+), and 9,10-diphenylanthracene using interdigitated array electrodes.  

PubMed

Interdigitated array electrodes (IDAs) were used to produce steady-state electrogenerated chemiluminescence (ECL) by annihilation of oxidized and reduced forms of a substituted boron dipyrromethene (BODIPY) dye, 9,10-diphenylanthracene (DPA), and ruthenium(II) tris(bypiridine) (Ru(bpy)3(2+)). Digital simulations were in good agreement with the experimentally obtained currents and light outputs. Coreactant experiments, using tri-n-propylamine and benzoyl peroxide as a sacrificial homogeneous reductant or oxidant, show currents corresponding to electrode reactions of the dyes and not the oxidation or reduction of the coreactants. The results show that interdigitated arrays can produce stable ECL where the light intensity is magnified due to the larger currents as a consequence of feedback between generator and collector electrodes in the IDA. The light output for ECL is around 100 times higher than that obtained with regular planar electrodes with similar area. PMID:23740271

Nepomnyashchii, Alexander B; Kolesov, G; Parkinson, B A

2013-07-10

293

Chemiluminescence analysis of the prooxidant and antioxidant effects of epigallocatechin-3-gallate.  

PubMed

The aim of this study was to investigate the mechanism of antioxidant and prooxidant effects of epigallocatechin-3-gallate (EGCG) using chemiluminescence analysis. Results showed that EGCG scavenged superoxide radical and H2O22 in a dose dependent manner. EGCG scavenged 50% of superoxide radical at 0.31 mM and scavenged 50% of H2O22 at 0.09 mM, demonstrating that EGCG has a stronger reactive oxygen species (ROS) scavenging activity than ascorbic acid. Effects of EGCG on free radical-induced DNA oxidative damage were investigated. EGCG had protective effect on DNA at low concentrations (2-30 mM), but it enhanced the DNA oxidative damage at higher concentrations (>60 mM), exhibiting a prooxidant effect on DNA. EGCG showed a greater reducing power on iron ions, reducing Fe3+ to Fe2+, which accelerates the generation of hydroxyl radical from the Fenton reaction. At low concentrations, ROS scavenging activity of EGCG might predominate over its reducing power and lead to its protective effect on DNA. However, relatively higher reducing power of EGCG at higher concentrations may gradually predominate over its ROS scavenging activity and result in the prooxidant effect of EGCG on DNA. PMID:17392095

Tian, Bing; Sun, Zongtao; Xu, Zhenjian; Hua, Yuejin

2007-01-01

294

Simultaneous chemiluminescence determination of thebaine and noscapine using support vector machine regression  

NASA Astrophysics Data System (ADS)

In this work, a batch chemiluminescence (CL) method has been proposed for the simultaneous determination of two structurally similar alkaloids, noscapine and thebaine. The method is based on the kinetic distinction of the CL reactions of noscapine and thebaine with Ru(bipy) 32+ and Ce(IV) system in a sulfuric acid medium. The least squared support vector machine (LS-SVM) regression was applied for relating the concentrations of both compounds to their CL profiles. The parameters of the model consisting of ?2 and ? were optimized by constructing LS-SVM models with all possible combinations of these two parameters to select the model with the minimum root mean squared error of cross validation (RMSECV) as the best. The parameters of this model were then selected as optimized values. Under the optimized experimental conditions for both compounds, the detection limits obtained using the LS-SVM regression were 0.08 and 0.1 ?mol L -1 for noscapine and thebaine, respectively. The proposed method was utilized for the simultaneous determination of the compounds in pharmaceutical formulations and plasma samples with satisfactory results.

Ensafi, Ali A.; Hasanpour, F.; Khayamian, T.; Mokhtari, A.; Taei, M.

2010-02-01

295

A High Sensitivity Micro Format Chemiluminescence Enzyme Inhibition Assay for Determination of Hg(II)  

PubMed Central

A highly sensitive and specific enzyme inhibition assay based on alcohol oxidase (AlOx) and horseradish peroxidase (HRP) for determination of mercury Hg(II) in water samples has been presented. This article describes the optimization and miniaturization of an enzymatic assay using a chemiluminescence reaction. The analytical performance and detection limit for determination of Hg(II) was optimized in 96 well plates and further extended to 384 well plates with a 10-fold reduction in assay volume. Inhibition of the enzyme activity by dissolved Hg(II) was found to be linear in the range 5–500 pg·mL?1 with 3% CV in inter-batch assay. Due to miniaturization of assay in 384 well plates, Hg(II) was measurable as low as 1 pg·mL?1 within 15 min. About 10-fold more specificity of the developed assay for Hg(II) analysis was confirmed by challenging with interfering divalent metal ions such as cadmium Cd(II) and lead Pb(II). Using the proposed assay we could successfully demonstrate that in a composite mixture of Hg(II), Cd(II) and Pb(II), inhibition by each metal ion is significantly enhanced in the presence of the others. Applicability of the proposed assay for the determination of the Hg(II) in spiked drinking and sea water resulted in recoveries ranging from 100–110.52%. PMID:22163555

Deshpande, Kanchanmala; Mishra, Rupesh K.; Bhand, Sunil

2010-01-01

296

Agonist-induced peroxynitrite production from endothelial cells.  

PubMed

Nitric oxide reacts with superoxide to form peroxynitrite, a potential mediator of oxidant-induced cellular injury. The endothelium is a primary target of injury in many pathological states, including acute lung injury, sepsis, multiple organ failure syndrome, and atherosclerosis, where enhanced production of nitric oxide and superoxide occurs simultaneously. It was hypothesized that stimulation of endothelial cell nitric oxide production would result in formation of peroxynitrite. Immediate oxidant production was detected by luminol- and lucigenin-enhanced chemiluminescence from cultured bovine aortic endothelial cells exposed to bradykinin or to the calcium ionophore A23187. Luminol-enhanced chemiluminescence was efficiently inhibited by the nitric oxide synthase inhibitor nitro-L-arginine methyl ester and by superoxide dismutase, implying dependence on the presence of both nitric oxide and superoxide for oxidant production. Inhibition of luminol-enhanced chemiluminescence by nitro-L-arginine methyl ester was partially reversed by L-arginine, but not by D-arginine. Cysteine, methionine, and urate, known inhibitors of peroxynitrite-mediated oxidation, inhibited luminol-enhanced chemiluminescence, while the hydroxyl radical scavengers, mannitol and dimethylsulfoxide, and catalase did not. Bicarbonate increased luminol-enhanced chemiluminescence in a concentration-dependent manner. Superoxide production, detected by lucigenin-enhanced chemiluminescence, was slightly increased in the presence of nitro-L-arginine methyl ester, suggesting that endothelial cell-produced superoxide was partially metabolized by reaction with nitric oxide. These results are consistent with agonist-induced peroxynitrite production by endothelial cells and suggests that peroxynitrite may have an important role in oxidant-induced endothelial injury. PMID:8179319

Kooy, N W; Royall, J A

1994-05-01

297

Sonochemical synthesis of Ag nanoclusters: electrogenerated chemiluminescence determination of dopamine.  

PubMed

We report a facile one-pot sonochemical approach to preparing highly water-soluble Ag nanoclusters (NCs) using bovine serum albumin as a stabilizing agent and reducing agent in aqueous solution. Intensive electrogenerated chemiluminescence (ECL) was observed from the as-prepared Ag (NCs) and successfully applied for the ECL detection of dopamine with high sensitivity and a wide detection range. A possible ECL mechanism is proposed for the preparation of Ag NCs. With this method, the dopamine concentration was determined in the range of 8.3 × 10(-9) to 8.3 × 10(-7) mol/L without the obvious interference of uric acid, ascorbic acid and some other neurotransmitters, such as serotonin, epinephrine and norepinephrine, and the detection limit was 9.2 × 10(-10) mol/L at a signal/noise ratio of 3. PMID:23418144

Liu, Tao; Zhang, Lichun; Song, Hongjie; Wang, Zhonghui; Lv, Yi

2013-01-01

298

Ester oxidation on an aluminum surface using chemiluminescence  

NASA Technical Reports Server (NTRS)

The oxidation characteristics of a pure ester (trimethyolpropane triheptanoate) were studied by using a chemiluminescence technique. Tests were run in a thin film microoxidation apparatus with an aluminum alloy catalyst. Conditions included a pure oxygen atmosphere and a temperature range of 176 to 206 C. Results indicated that oxidation of the ester (containing .001 M diphenylanthracene as an intensifier) was accompanied by emission of light. The maximum intensity of light emission was a function of the amount of ester, the concentration of intensifier, and the test temperature. The induction period, or the time to reach one-half of maximum intensity was inversely proportional to test temperature. Decreases in light emission at the later stages of a test were caused by depletion of the intensifier.

Jones, William R., Jr.; Meador, Michael A.; Morales, Wilfredo

1986-01-01

299

ORIGINAL RESEARCH Detection of hydrogen peroxide with chemiluminescent micelles  

E-print Network

Abstract: The overproduction of hydrogen peroxide is implicated in the progress of numerous life-threatening diseases and there is a great need for the development of contrast agents that can detect hydrogen peroxide in vivo. In this communication, we present a new contrast agent for hydrogen peroxide, termed peroxalate micelles, which detect hydrogen peroxide through chemiluminescence, and have the physical/chemical properties needed for in vivo imaging applications. The peroxalate micelles are composed of amphiphilic peroxalate based copolymers and the fluorescent dye rubrene, they have a ‘stealth ’ polyethylene glycol (PEG) corona to evade macrophage phagocytosis, and a diameter of 33 nm to enhance extravasation into permeable tissues. The peroxalate micelles can detect nanomolar concentrations of hydrogen peroxide (?50 nM) and thus have the sensitivity needed to detect physiological concentrations of hydrogen peroxide. We anticipate numerous applications of the peroxalate micelles for in vivo imaging of hydrogen peroxide, given their high sensitivity, small size, and biocompatible PEG corona.

Dongwon Lee; Venkata R Erigala; Madhuri Dasari; Junhua Yu; Robert M Dickson; Niren Murthy; The Wallace; H. Coulter Department

300

Computational modeling Flow-injection chemiluminescent immunoassay for ?-fetoprotein based on epoxysilane modified glass microbeads  

Microsoft Academic Search

A flow-injection chemiluminescent immunoassay system based on a novel transparent immunoaffinity reactor is proposed for the quantitation of ?-fetoprotein. The reactor prepared with ?-fetoprotein immobilized epoxysilane modified glass microbeads was used as an immunosensor for chemiluminescent detection. With a non-competitive immunoassay format, the proposed immunosensor system is a low cost, flexible and rapid assay for ?-fetoprotein. After an off-line incubation

Zhifeng Fu; Chen Hao; Xiaoqing Fei; Huangxian Ju

301

Detection of Parvovirus B19 DNA in Bone Marrow Cells by Chemiluminescence In Situ Hybridization  

Microsoft Academic Search

A chemiluminescence in situ hybridization method was developed for the search of B19 parvovirus DNA in bone marrow cells, employing digoxigenin-labeled B19 DNA probes, immunoenzymatically detected with a highly sensitive 1,2-dioxetane phosphate as chemiluminescent substrate. The light emitted from the in situ- hybridized probe was analyzed and measured by a high-performance luminograph connected to an optical microscope and to a

MONICA MUSIANI; ALDO RODA; MARIALUISA ZERBINI; GIOVANNA GENTILOMI; PATRIZIA PASINI; GIORGIO GALLINELLA; ANDSIMONA VENTUROLI

302

Development of a multichannel Fourier-transform spectrometer to measure weak chemiluminescence: Application to the emission of singlet-oxygen dimol in the decomposition of hydrogen peroxide with gallic acid and K 3[Fe(CN) 6  

NASA Astrophysics Data System (ADS)

A Fourier-transform spectrometer equipped with a Savart-plate polarization interferometer was developed for observation of weak chemiluminescence and applied to a measurement of emission spectra in the decomposition of hydrogen peroxide with gallic acid and K 3[Fe(CN) 6]. The band appearing at ˜580 nm in the chemiluminescence spectrum was assigned to the emission of singlet-oxygen dimol, the peak wavelength being shifted from that observed in the reaction of hydrogen peroxide with sodium hypochlorite, ˜633 nm. The band intensity was increased with the increasing concentration of K 3[Fe(CN) 6] up to ˜100 mM, and thereafter the peak wavelength was shifted from 580 to 700 nm with a decrease in the intensity.

Tsukino, Kazuo; Satoh, Toshihiro; Ishii, Hiroshi; Nakata, Munetaka

2008-05-01

303

Dysprosium-sensitized chemiluminescence system for the determination of enoxacin in pharmaceutical preparations and biological fluids with flow-injection sampling.  

PubMed

A novel trivalence dysprosium(Dy(3+))-sensitized chemiluminescence method was developed for the first time for the determination of enoxacin (ENX) using flow-injection sampling based on the chemiluminescence (CL) associated with the reaction of the Dy(3+)-cerium(Ce(IV))-S(2)O(3) (2-)-ENX system and the Dy(3+)-MnO(4) (-) S(2)O(3) (2-)-ENX system. The analytical conditions for CL emission were investigated and optimized. The relationship between the CL intensity of ENX and its concentration has good linearity, with a correlation coefficient of 0.9984-0.9994. The limit of detection (LOD, 3sigma) was 0.20 ng/mL for the Dy(3+)-ENX-S(2)O(3)(2-)-Ce(IV)-H(2)SO(4) system and 0.22 ng/mL for the Dy(3+)-ENX-S(2)O(3)(2-)-MnO(4) (-)-HNO(3) system. The relative standard deviation (RSD, n = 11) was 1.8% for 11 determinations of 60 ng/mL ENX. The proposed method was applied to the analysis of ENX in injections, serum and urine samples with a recovery of 98%-105%. A possible mechanism for this sensitized CL reaction is discussed by comparing the CL spectra with the fluorescence emission spectra. The proposed method represents a wide linear range, high sensitivity and accuracy, and can be used for the routine determination of ENX in pharmaceutical preparations and biological fluids. PMID:20355186

Sun, Han-wen; Wu, Yuan-yuan; Li, Li-qing

2009-03-01

304

A low budget luminometer for sensitive chemiluminescent immunoassays.  

PubMed

We have designed a simple luminometer based on a reasonably priced Peltier-cooled charge-coupled device (CCD) camera, housed in a light-tight box, with straightforward lens imaging and a simple platform for a microtitre or other assay format. The quantitative readout of the CCD image is recorded on a PC using customised software. The instrument can be assembled in a standard university workshop for under pound3000, compared with the cheapest commercial instruments retailing at pound10,000 and above. Consistent with the general view on chemiluminescent assays, the sensitivity is 10-100 times greater than that obtained with parallel ELISA's using a chromogenic substrate. A unique feature of the CCD format is that it enables assays to be carried out on arrays of minidots and even nanodots of antigen on the floor of each microtitre well. This permits direct comparison and standardisation of reactivity of a single sample against several antigens and economy in the use of reagents, test sample and technician time; finger-prick samples of blood can be analysed. The instrument should have widespread applicability in developing countries and, indeed, in any laboratories with hard-pressed budgets. PMID:10669767

Porakishvili, N; Fordham, J L; Charrel, M; Delves, P J; Lund, T; Roitt, I M

2000-02-01

305

Chemiluminescence. 1977-April 1980, 1980 (citations from the International Aerospace Abstracts data base). Report for 1977-April 1980  

SciTech Connect

Cited works describe the use of chemiluminescence for aurora and upper-atmosphere analyses, evaluation of chemical laser candidates, studies of jet and combustor dynamics, smog analysis and other work. Sources and forms of chemiluminescence and measurement techniques are described. (Contains 92 citations)

Young, C.G.

1980-05-01

306

The Oxidant-Scavenging Abilities in the Oral Cavity May Be Regulated by a Collaboration among Antioxidants in Saliva, Microorganisms, Blood Cells and Polyphenols: A Chemiluminescence-Based Study  

PubMed Central

Saliva has become a central research issue in oral physiology and pathology. Over the evolution, the oral cavity has evolved the antioxidants uric acid, ascorbate reduced glutathione, plasma-derived albumin and antioxidants polyphenols from nutrients that are delivered to the oral cavity. However, blood cells extravasated from injured capillaries in gingival pathologies, or following tooth brushing and use of tooth picks, may attenuate the toxic activities of H2O2 generated by oral streptococci and by oxidants generated by activated phagocytes. Employing a highly sensitive luminol-dependent chemiluminescence, the DPPH radical and XTT assays to quantify oxidant-scavenging abilities (OSA), we show that saliva can strongly decompose both oxygen and nitrogen species. However, lipophilic antioxidant polyphenols in plants, which are poorly soluble in water and therefore not fully available as effective antioxidants, can nevertheless be solubilized either by small amounts of ethanol, whole saliva or also by salivary albumin and mucin. Plant-derived polyphenols can also act in collaboration with whole saliva, human red blood cells, platelets, and also with catalase-positive microorganisms to decompose reactive oxygen species (ROS). Furthermore, polyphenols from nutrient can avidly adhere to mucosal surfaces, are retained there for long periods and may function as a “slow- release devises” capable of affecting the redox status in the oral cavity. The OSA of saliva is due to the sum result of low molecular weight antioxidants, albumin, polyphenols from nutrients, blood elements and microbial antioxidants. Taken together, saliva and its antioxidants are considered regulators of the redox status in the oral cavity under physiological and pathological conditions. PMID:23658797

Ginsburg, Isaac; Kohen, Ron; Shalish, Miri; Varon, David; Shai, Ella; Koren, Erez

2013-01-01

307

The oxidant-scavenging abilities in the oral cavity may be regulated by a collaboration among antioxidants in saliva, microorganisms, blood cells and polyphenols: a chemiluminescence-based study.  

PubMed

Saliva has become a central research issue in oral physiology and pathology. Over the evolution, the oral cavity has evolved the antioxidants uric acid, ascorbate reduced glutathione, plasma-derived albumin and antioxidants polyphenols from nutrients that are delivered to the oral cavity. However, blood cells extravasated from injured capillaries in gingival pathologies, or following tooth brushing and use of tooth picks, may attenuate the toxic activities of H2O2 generated by oral streptococci and by oxidants generated by activated phagocytes. Employing a highly sensitive luminol-dependent chemiluminescence, the DPPH radical and XTT assays to quantify oxidant-scavenging abilities (OSA), we show that saliva can strongly decompose both oxygen and nitrogen species. However, lipophilic antioxidant polyphenols in plants, which are poorly soluble in water and therefore not fully available as effective antioxidants, can nevertheless be solubilized either by small amounts of ethanol, whole saliva or also by salivary albumin and mucin. Plant-derived polyphenols can also act in collaboration with whole saliva, human red blood cells, platelets, and also with catalase-positive microorganisms to decompose reactive oxygen species (ROS). Furthermore, polyphenols from nutrient can avidly adhere to mucosal surfaces, are retained there for long periods and may function as a "slow-release devises" capable of affecting the redox status in the oral cavity. The OSA of saliva is due to the sum result of low molecular weight antioxidants, albumin, polyphenols from nutrients, blood elements and microbial antioxidants. Taken together, saliva and its antioxidants are considered regulators of the redox status in the oral cavity under physiological and pathological conditions. PMID:23658797

Ginsburg, Isaac; Kohen, Ron; Shalish, Miri; Varon, David; Shai, Ella; Koren, Erez

2013-01-01

308

One-pot synthesis of GO/AgNPs/luminol composites with electrochemiluminescence activity for sensitive detection of DNA methyltransferase activity.  

PubMed

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. PMID:25129507

Zhao, Hui-Fang; Liang, Ru-Ping; Wang, Jing-Wu; Qiu, Jian-Ding

2015-01-15

309

Effect of fuel type on equivalence ratio measurements using chemiluminescence in premixed flames  

NASA Astrophysics Data System (ADS)

Local temporally-resolved measurements of chemiluminescent intensity from OH ?, CH ? and C ?2 radicals were obtained in premixed counterflow flames operating with propane and prevaporised fuels (isooctane, ethanol and methanol), for different equivalence ratios and strain rates. The results quantified independently the effects of fuel type, strain rate and equivalence ratio on chemiluminescent emissions from flames. The ability of chemiluminescent intensity from OH ?, CH ? and C ?2 radicals to indicate heat release rate depends strongly on fuel type. The intensity ratio OH ?/CH ? has a monotonic decrease with equivalence ratio for all fuels and can be used to measure equivalence ratio of the reacting mixture. For propane and isooctane, the OH ?/CH ? ratio remains independent of flame strain rate, whereas some dependence is observed for ethanol and methanol.

Orain, Mikaël; Hardalupas, Yannis

2010-05-01

310

Laboratory Studies of FeO and NiO Chemiluminescence  

NASA Astrophysics Data System (ADS)

Although the terrestrial nightglow spectrum has been studied for over a century, new identifications of spectral features continue to be made. Recently, FeO* continuum emissions in the mesosphere were identified by comparison of results from the OSIRIS spectrometer to existing laboratory spectra [1]. This discovery has sparked a renewal of interest in the reactions of meteoric metals with mesospheric gases [2,3], and has motivated the current study. We report laboratory-based chemiluminescence spectra from the reactions Fe + O3 and Ni + O3 produced under various conditions. Iron and nickel vapor was prepared in a vacuum cell using laser ablation at 248 and 800 nm in the presence of ozone. Emission spectra from FeO* and NiO* were recorded in the region of 450-700 nm using a commercial fiber-coupled spectrometer and compared to previous results using different methods. Knowledge of the excited-state production efficiency of Fe + O3 ? FeO* + O2 and the analogous reaction with Ni is critical in modeling upper atmospheric dynamics of meteoric metal layers. The only relevant experimental study in the literature for iron oxide is from West and Broida [4], who reported a yield of approximately 2% at around 1 Torr, in stark contrast with the 100% efficiency used in relevant model calculations [5]. This work was supported by the National Science Foundation's Aeronomy Program under grant AGS-0637433. References 1. W.F.J. Evans, R.L. Gattinger, T.G. Slanger, D.V. Saran, D.A. Degenstein, and E.J. Llewellyn, Geophys. Res. Lett., 37, L22105 (2010). 2. D.V. Saran, T.G. Slanger, W. Feng, and J.M.C. Plane, J. Geophys. Res. 116, D12303 (2011). 3. R.L. Gattinger, W.F.J. Evans, and E.J. Llewellyn, Canadian Journal of Physics 89, 869 (2011). 4. J.B. West and H.P. Broida, J. Chem. Phys. 62, 2566 (1975 ). 5. C.S. Gardner, J.M.C. Plane, W.L. Pan, T. Vondrak, B.J. Murray, and X.Z. Chu, J. Geophys. Res. 110, D10302 (2005).

Kalogerakis, K. S.; Bartlett, N. C.; Copeland, R. A.; Slanger, T. G.

2013-12-01

311

Highly efficient electrogenerated chemiluminescence of Au38 nanoclusters.  

PubMed

An investigation of mechanisms for the near-infrared (NIR) electrogenerated chemiluminescence/electrochemiluminescence (ECL) of Au38(SC2H4Ph)24 (Au38, SC2H4Ph = 2-phenylethanethiol) nanoclusters both in annihilation and coreactant paths is reported. Essentially, no ECL emission was produced in the annihilation route over the potential range of the accessible redox states of Au38, because of the short lifetime and/or low reactivity of the electrogenerated Au38 intermediates necessary for ECL. Highly efficient light emission with a nominal peak wavelength of 930 nm in the NIR region was observed in the anodic region upon addition of tri-n-propylamine (TPrA) as the coreactant. The ECL mechanisms were elucidated by means of ECL-potential curves and spooling ECL spectroscopy. It was discovered that the Au38(+*) (and also Au38(3+*)) were electrogenerated as the major excited species in the light emission processes. Benzoyl peroxide was also used as a coreactant in the cathodic potential range from which benzoate radicals, with a high oxidizing power, were formed. These radicals accepted electrons from the electrogenerated Au38(2-) HOMO, resulting in the Au38(-*) excited state that emitted light at 930 nm. The photoluminescence of the various Au38 charge states, namely, Au38(2-), Au38(-), Au38(0), Au38(+), Au38(2+), and Au38(4+), electrogenerated in situ, indicated no significant difference in the emission peak wavelength. This information allowed a careful mapping of the relevant ECL mechanisms. It was found that the ECL efficiency could reach an efficiency of 3.5 times as high as that of the Ru(bpy)3(2+)/TPrA system. PMID:25088234

Hesari, Mahdi; Workentin, Mark Steven; Ding, Zhifeng

2014-08-26

312

Electrochemistry and electrogenerated chemiluminescence of three phenanthrene derivatives, enhancement of radical stability, and electrogenerated chemiluminescence efficiency by substituent groups.  

PubMed

The electrochemistry and electrogenerated chemiluminescence (ECL) of three phenanthrene derivatives, 3,6-diphenyl-9,10-bis-(4-tert-butylphenyl)phenanthrene (TphP, T1), 3,6-di(naphthalen-2-yl)-9,10-bis(4-tert-butylphenyl)phenanthrene (TnaP, T2), and 3,6-di(pyrene-1-yl)-9,10-bis(4-tert-butylphenyl)phenanthrene (TpyP, T3), are investigated in an acetonitrile:benzene (v:v = 1:1) solvent. Cyclic voltammetry (CV) of the three derivatives shows reversible reduction waves and less chemically reversible oxidation waves at low scan rates. The CV character becomes more reversible, and the stability of the radical cations increases as the conjugation of the substituent groups appended to the phenanthrene increases. This finding indicates that the radical ion stabilities in phenanthrene derivatives are drastically improved by increasing the conjugation of the substituent groups; thus, electrochemically stable radical ions can be obtained by introducing more conjugated groups to the phenanthrene center. Additionally, ECL is generated for all compounds by radical ion annihilation, and the ECL spectrum shows good agreement with the fluorescence emission, assigned as emission by the S-route. ECL efficiencies for radical ion annihilation are 0.004 for TphP, 0.16 for TnaP, and 0.25 for TpyP, respectively, and the ECL efficiency increases with the conjugation of the substituent groups appended to the phenanthrene increases. Radical ion annihilation produced by potential steps exhibits asymmetric ECL transients in which the cathodic ECL pulse is smaller than the anodic pulse due to the instability of the radical cation. These molecules can produce a stronger ECL, which can be observed by the naked eye in a lighted room, on reduction in the presence of a coreactant (benzoyl peroxide). PMID:23705853

Qi, Honglan; Chen, Yu-Han; Cheng, Chien-Hong; Bard, Allen J

2013-06-19

313

Determination of Catalase Activity at Physiological Hydrogen Peroxide Concentrations  

Microsoft Academic Search

A method for the determination of catalase activity (EC 1.11.1.6.) in homogenates and cell suspensions is described by following the decomposition of H2O2at physiological H2O2levels. This first chemiluminescence assay for catalase activity is based on the reaction of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione) and NaOCl. The chemiluminescence of this reaction specifically depends on the H2O2concentration and shows fast kinetics of less than 2

Sebastian Mueller; Hans-Dieter Riedel; Wolfgang Stremmel

1997-01-01

314

Fabrication technology of chemiluminescent sensitive elements for rocket-borne ozone detectors  

NASA Astrophysics Data System (ADS)

Attention is given to the technology behind the fabrication of chemiluminescent sensitive elements for rocket-borne ozone detectors. High-silica microporous glass is the basic material required for these detectors. It is noted that the luminophor consists of rhodamine-C and gallic acid, and that the desired ratio of these components depends on the sensitivity of a particular specimen to ozone.

Kononkov, V. A.; Lelikova, A. I.; Perov, S. P.

315

Thermal oxidation of hydroxyl-terminated polybutadiene rubber I. Chemiluminescence studies  

Microsoft Academic Search

The chemiluminescence (CL) intensity from a hydroxyl-terminated polybutadiene (HTPB) rubber was measured during isothermal oxidation at temperatures ranging from 70 to 130°C. The CL isotherms were characterised by an approximately constant level of intensity followed by a rapid increase to a maximum intensity. The initial intensity as well as the maximum intensity levels of the different isotherms obeyed an Arrhenius

Gustav Ahlblad; Torbjörn Reitberger; Björn Terselius; Bengt Stenberg

1999-01-01

316

Easy estimation of the progress of artificial weathering of palm fiber-polypropylene composites by chemiluminescence  

Microsoft Academic Search

Date palm leaves were compounded with polypropylene (PP) and UV stabilizers to form composite materials. Residual thermo-oxidation stability of such composites undergone to accelerated weathering in Xenotest has been investigated by chemiluminescence method. It has been found that composites are much more stable than PP alone which was attributed to the direct interaction of cellulose fibres (reinforcing effect) and lignin

B. Abu-Sharkh; J. Rychlý; L. Matisová-Rychlá

2005-01-01

317

Tracermer signal generators: an arborescent approach to the incorporation of multiple chemiluminescent labels.  

PubMed

The synthesis, conjugation, and chemiluminescent evaluation of zero, first, and second order acridinium-based Tracermer signal generators are described. Members of this family of labels have potential use as tracers in diagnostic assays and are structurally similar to arborol dendrimers. Tracermer-BSA conjugates showed up to a sixfold increase in light emission compared to the normal acridinium label. PMID:9934477

Adamczyk, M; Fishpaugh, J; Mattingly, P G; Shreder, K

1998-12-15

318

Selective chemiluminescence method for monitoring of vitamin K homologues in rheumatoid arthritis patients  

Microsoft Academic Search

Vitamin K is a fat-soluble vitamin involved in blood coagulation and bone metabolism. The detection and monitoring of vitamin K homologues in rheumatoid arthritis (RA) patients is a challenging problem due to the smaller concentrations of vitamin K and the presence of several interfering medications. Therefore, this study aimed to develop a new highly sensitive and selective chemiluminescence (CL) method

Sameh Ahmed; Naoya Kishikawa; Kaname Ohyama; Takahiro Imazato; Yukitaka Ueki; Naotaka Kuroda

2011-01-01

319

Efficient electrogenerated chemiluminescence from CdTe quantum dots with coreactants  

Microsoft Academic Search

While quantum dots (QDs) have attracted much interest in electrogenerated chemiluminescence (ECL) as a light emitter due to their high quantum yield and bandgap tunability, the fundamental ECL characteristics of QDs in various conditions still remain elusive. In this study, we investigate the ECL generation from CdTe QDs dispersed in organic solvents in the presence of a coreactant. ECL generation

Ik-Soo Shin; Hasuck Kim; Jin Ho Bang

2011-01-01

320

The Synthesis and Chemiluminescence of a Stable 1,2-Dioxetane.  

ERIC Educational Resources Information Center

Background information, laboratory procedures, and discussion of results are provided for the synthesis and chemiluminescence of adamantylideneadamantane-1,2-dioxetane (I). Results provided were obtained during a normal junior level organic laboratory course. All intermediates and products were identified using routine spectroscopic analysis.…

Meijer, E. W.; Wynberg, Hans

1982-01-01

321

Laser-saturated fluorescence of nitric oxide and chemiluminescence measurements in premixed ethanol flames  

SciTech Connect

In this study, nitric oxide laser-saturated fluorescence (LSF) measurements were acquired from premixed ethanol flames at atmospheric pressure in a burner. NO-LSF experimental profiles for fuel-rich premixed ethanol flames ({phi} = 1.34 and {phi} = 1.66) were determined through the excitation/detection scheme of the Q{sub 2}(26.5) rotational line in the A{sup 2}{sigma}{sup +} - X{sup 2}{pi} (0,0) vibronic band and {gamma}(0,1) emission band. A calibration procedure by NO doping into the flame was applied to establish the NO concentration profiles in these flames. Chemiluminescent emission measurements in the (0, 0) vibronic emission bands of the OH{sup *} (A{sup 2}{sigma}{sup +} - X{sup 2}{pi}) and CH{sup *}(A{sup 2}{delta} - X{sup 2}{pi}) radicals were also obtained with high spatial and spectral resolution for fuel-rich premixed ethanol flames to correlate them with NO concentrations. Experimental chemiluminescence profiles and the ratios of the integrated areas under emission spectra (A{sub CH*}/A{sub CH*}(max.) and A{sub CH*}/A{sub OH*}) were determined. The relationships between chemiluminescence and NO concentrations were established along the premixed ethanol flames. There was a strong connection between CH{sup *} radical chemiluminescence and NO formation and the prompt-NO was identified as the governing mechanism for NO production. The results suggest the optimum ratio of the chemiluminescence of two radicals (A{sub CH*}/A{sub OH*}) for NO diagnostic purposes. (author)

Marques, Carla S.T.; Barreta, Luiz G.; Sbampato, Maria E.; dos Santos, Alberto M. [Aerothermodynamic and Hypersonic Division, Institute of Advanced Studies - General Command of Aerospatial Technology, Rodovia dos Tamoios, km 5.5, 12228-001 Sao Jose dos Campos - SP (Brazil)

2010-11-15

322

7,7,8,8-tetracyanoquinodimethane chemiluminescence sensitized by Rhodamine B on surfactant bilayer membrane assemblies for determination of sulphide by a flow-injection method.  

PubMed

A new chemiluminescence system is described for selective determination of sulphide by a flow-injection method. The weak light emitted from the reaction between 7,7,8,8-tetracyanoquinodimethane and sulphide is efficiently sensitized by Rhodamine B in alkaline solution containing dioctadecyldimethylammonium chloride bilayer membrane aggregates and acetonitrile. The limit of determination is 0.05 ng (injection of 30 mul of 5 x 10(-8)M sulphide), the linear range is two orders of magnitude, the sampling rate is 240/hr, and the relative standard deviation is 3.0% for 0.3 ng of sulphide. Manganese(II), the strongest enhancing species after sulphide ion, provides a signal 1.1% of that for sulphide ion. Manganese(II), iron(II), and species forming precipitates with sulphide ion interfere, but other sulphur anions such as sulphite, sulphate, thiosulphate, and thiocyanate do not. PMID:18964747

Xue-Xin, Q; Yue-Ying, G; Yamada, M; Kobayashi, E; Suzuki, S

1989-04-01

323

Microsomal chemiluminescence of benzo[a]pyrene-7,8-dihydrodiol and its synthetic analogues trans- and cis-1-methoxyvinylpyrene.  

PubMed

The cis- and trans-methoxyvinylpyrene (MVP) analogues of benzo[a]pyrene-7,8-dihydrodiol (7,8-diol) produce specific microsomal chemiluminescence comparable to that produced from 7,8-diol in Aroclor-induced rat liver microsome preparations. The chemiluminescence quantum yields, emission spectra, and the concentration and the temporal kinetics of these three substrates have been examined. Radiolabelled 7,8-diol and t-MVP exhibit significant covalent binding (more than 14%) to microsomal protein when metabolized enzymatically. The extreme quenching of the dioxetane chemiluminescence by both microsomes and phosphatidylcholine, as a model phospholipid, implies that despite the low quantum yield (approx. 10(-8) photons per substrate molecule) for microsomal chemiluminescence of these substrates, a significant fraction of their microsomal oxygenations may proceed via a dioxetane pathway. PMID:3708001

Thompson, A; Biggley, W H; Posner, G H; Lever, J R; Seliger, H H

1986-06-19

324

Synthesis of PbS/PbI2 nanocomposites in mixed solvent and their composition-dependent electrogenerated chemiluminescence performance.  

PubMed

PbS/PbI2 nanocomposites were prepared by choosing K[PbI3] as both a lead salt and an iodide precursor and acetone/water as a reaction medium. It was found that the amount of the PbI2 component could be controlled, to some extent, by varying the amount of water used. Further, this simple bicomponent precursor-based synthetic route can be extended to prepare other lead-containing nanocomposites such as Pb3O4/PbI2 and PbSe/PbI2. Because of the heavy-atom effect, PbS/PbI2 nanocomposites exhibited good and composition-dependent electrogenerated chemiluminescence (ECL) performance, demonstrating their potential in the development of novel ECL sensors for analytical and clinical applications. These interesting findings would encourage us to gain deep insight on these phenomena, which could lead to the further development of these new inorganic materials and their applications. PMID:25083825

Liu, Suli; Zhang, Long; Li, Yanrong; Han, Min; Dai, Zhihui; Bao, Jianchun

2014-08-18

325

Unprecedented hydroxyl radical-dependent two-step chemiluminescence production by polyhalogenated quinoid carcinogens and H2O2  

PubMed Central

Most chemiluminescence (CL) reactions usually generate only one-step CL, which is rarely dependent on the highly reactive and biologically/environmentally important hydroxyl radicals (•OH). Here, we show that an unprecedented two-step CL can be produced by the carcinogenic tetrachloro-1,4-benzoquinone (also known as p-chloranil) and H2O2, which was found to be well-correlated to and directly dependent on its two-step metal-independent production of •OH. We proposed that •OH-dependent formation of quinone-dioxetane and electronically excited carbonyl species might be responsible for this unusual two-step CL production by tetrachloro-1,4-benzoquinone/H2O2. This is a unique report of a previously undefined two-step CL-producing system that is dependent on intrinsically formed •OH. These findings may have potential applications in detecting and quantifying •OH and the ubiquitous polyhalogenated aromatic carcinogens, which may have broad biological and environmental implications for future research on these types of important species. PMID:22988069

Zhu, Ben-Zhan; Mao, Li; Huang, Chun-Hua; Qin, Hao; Fan, Rui-Mei; Kalyanaraman, Balaraman; Zhu, Jun-Ge

2012-01-01

326

A 3D-printed device for a smartphone-based chemiluminescence biosensor for lactate in oral fluid and sweat.  

PubMed

Increasingly, smartphones are used as portable personal computers, revolutionizing communication styles and entire lifestyles. Using 3D-printing technology we have made a disposable minicartridge that can be easily prototyped to turn any kind of smartphone or tablet into a portable luminometer to detect chemiluminescence derived from enzyme-coupled reactions. As proof-of-principle, lactate oxidase was coupled with horseradish peroxidase for lactate determination in oral fluid and sweat. Lactate can be quantified in less than five minutes with detection limits of 0.5 mmol L(-1) (corresponding to 4.5 mg dL(-1)) and 0.1 mmol L(-1) (corresponding to 0.9 mg dL(-1)) in oral fluid and sweat, respectively. A smartphone-based device shows adequate analytical performance to offer a cost-effective alternative for non-invasive lactate measurement. It could be used to evaluate lactate variation in relation to the anaerobic threshold in endurance sport and for monitoring lactic acidosis in critical-care patients. PMID:25343380

Roda, Aldo; Guardigli, Massimo; Calabria, Donato; Calabretta, Maria Maddalena; Cevenini, Luca; Michelini, Elisa

2014-11-10

327

Label-Free Sensitive Electrogenerated Chemiluminescence Aptasensing Based on Chitosan/Ru(bpy)3(2+)/Silica Nanoparticles Modified Electrode.  

PubMed

In this work, a label-free and sensitive electrogenerated chemiluminescence (ECL) aptasensing scheme for K(+) was developed based on G-rich DNA aptamer and chitosan/Ru(bpy)3(2+)/silica (CRuS) nanoparticles (NPs)-modified glass carbon electrode. This ECL aptasensing approach has benefited from the observation that the G-rich DNA aptamer at the unfolded state showed more ECL enhancing signal at CRuS NPs-modified electrode than the binding state with K(+), which folds into G-quadruplex structure. As such, the decreasing ECL signals could be used to detect K(+). Compared to other aptasensing K(+) approaches previously reported, the proposed ECL sensing scheme is a label-free aptasensing strategy, which eliminates the labeling, separation, and immobilization steps, and behaves in a simple, low-cost way. More importantly, because the proposed ECL sensing mechanism utilizes the nanosized ECL active CRuS NPs to sense the nanoscale conformation change from the aptamer binding to target, it is specific. In addition, due to the great conformation changes of the aptamer's G-bases on CRuS NPs and the excellent ECL enhancing effect of guanine bases to the Ru(bpy)3(2+) ECL reaction, a 0.3 nM detection limit for K(+) was achieved with the proposed ECL method. On the basis of these advantages, the proposed ECL aptasensing method was also successfully used to detect K(+) in colorectal cancer cells. PMID:25142310

Dang, Jie; Guo, Zhihui; Zheng, Xingwang

2014-09-16

328

Determination of organothiophosphorus pesticides in water by liquid chromatography and post-column chemiluminescence with cerium(IV).  

PubMed

A new, fast, selective and sensitive method has been developed for the simultaneous determination of nine organothiophosphorus (OTP) pesticides, namely omethoate, dimethoate, disulfoton-sulfoxide, methidathion, phosmet, malathion, diazinon, pirimiphos-methyl and chlorpyrifos. The pesticides were separated on a Kinetex C18 column by gradient elution with acetonitrile:water. A post-column basic hydrolysis of the pesticides and later a chemiluminescence (CL) reaction with cerium (IV) in acid medium was carried out. Hexadecylpyridinium chloride highly enhanced the CL emission. Under optimized conditions, linearity, precision, limits of detection and quantification, and accuracy were determined. Both selectivity and sensitivity were compared with those obtained with UV detection. In combination with SPE, limits of detection in the range 15-80ng/L and 5-30ng/L were obtained when 250mL and 1000mL of solution were treated, respectively. When applied to 250mL of sample the inter-day precision of the method was between 3.5% and 7.3% and the intra-day precision between 2.9% and 6.0%. The method was applied to determine OTP pesticides in spiked water samples from different origins: irrigation, river, sea, ground, spring, mineral and tap waters, being the percentage of recovery of added amounts near 100% form most of the pesticides. PMID:24685163

Catalá-Icardo, Mónica; Lahuerta-Zamora, Luis; Torres-Cartas, Sagrario; Meseguer-Lloret, Susana

2014-05-01

329

A Batch Chemiluminescence Determination of Enoxacin Using a Tris(1,10-phenanthroline)ruthenium(II)–Cerium(IV) System  

Microsoft Academic Search

A batch type chemiluminescence (CL) determination of enoxacin is described. In this work, it was observed that enoxacin could enhance the chemiluminescence (CL) emission Ru(phen)3\\u000a 2+–Ce(IV) system and this enhancement effect was dependent on the concentration of enoxacin, based on which, CL system was established for the determination of enoxacin. Under the optimum experimental conditions, the linear range and detection

Mohammad Mainul Karim; Sang Hak Lee; Hyun Sook Lee; Zun Ung Bae; Kyoung Hye Choi

2006-01-01

330

Linker-mediated modulation of the chemiluminescent signal from N(10)-(3-Sulfopropyl)-N-sulfonylacridinium-9-carboxamide tracers.  

PubMed

Four chemiluminescent N-sulfonylacridinium-9-carboxamide active esters (17-20) were prepared from the corresponding acids and coupled to both of the aminated phenobarbital (13) and N-(6-aminohexyl)phenytoin (16) haptens. The level of signal produced by chemiluminescent N-sulfonylacridinium-9-carboxamide phenobarbital and phenytoin tracers in a solid-phase immunoassay format was found to be modulated by at least 20-fold by the judicious choice of the reactive acridinium-hapten linking group. PMID:10995216

Adamczyk, M; Chen, Y Y; Fishpaugh, J R; Mattingly, P G; Pan, Y; Shreder, K; Yu, Z

2000-01-01

331

On use of CO{sub 2} chemiluminescence for combustion metrics in natural gas fired reciprocating engines.  

SciTech Connect

Flame chemiluminescence is widely acknowledged to be an indicator of heat release rate in premixed turbulent flames that are representative of gas turbine combustion. Though heat release rate is an important metric for evaluating combustion strategies in reciprocating engine systems, its correlation with flame chemiluminescence is not well studied. To address this gap an experimental study was carried out in a single-cylinder natural gas fired reciprocating engine that could simulate turbocharged conditions with exhaust gas recirculation. Crank angle resolved spectra (266-795 nm) of flame luminosity were measured for various operational conditions by varying the ignition timing for MBT conditions and by holding the speed at 1800 rpm and Brake Mean effective Pressure (BMEP) at 12 bar. The effect of dilution on CO*{sub 2}chemiluminescence intensities was studied, by varying the global equivalence ratio (0.6-1.0) and by varying the exhaust gas recirculation rate. It was attempted to relate the measured chemiluminescence intensities to thermodynamic metrics of importance to engine research -- in-cylinder bulk gas temperature and heat release rate (HRR) calculated from measured cylinder pressure signals. The peak of the measured CO*{sub 2} chemiluminescence intensities coincided with peak pressures within {+-}2 CAD for all test conditions. For each combustion cycle, the peaks of heat release rate, spectral intensity and temperature occurred in that sequence, well separated temporally. The peak heat release rates preceded the peak chemiluminescent emissions by 3.8-9.5 CAD, whereas the peak temperatures trailed by 5.8-15.6 CAD. Such a temporal separation precludes correlations on a crank-angle resolved basis. However, the peak cycle heat release rates and to a lesser extent the peak cycle temperatures correlated well with the chemiluminescent emission from CO*{sub 2}. Such observations point towards the potential use of flame chemiluminescence to monitor peak bulk gas temperatures as well as peak heat release rates in natural gas fired reciprocating engines.

Gupta, S. B.; Bihari, B.; Biruduganti, M.; Sekar, R.; Zigan, J. (Energy Systems); (Cummins Technical Center)

2011-01-01

332

Modification of production of reactive oxygen species in mouse peritoneal neutrophils on exposure to low-intensity modulated millimeter wave radiation  

Microsoft Academic Search

The effect of low-intensity modulated electromagnetic radiation of extremely high frequencies (EHF EMR) on the production of reactive oxygen species by mouse peritoneal neutrophils was investigated. The neutrophil activity in synergistic reaction of calcium ionophore A23187 and phorbol ester PMA was estimated by luminol-dependent chemiluminescence technique. The cells were irradiated for 20 min in the far-field zone of the channel

A. B Gapeyev; V. S Yakushina; N. K Chemeris; E. E Fesenko

1998-01-01

333

[The effect of sodium butyrate and luminol on reciprocal exchanges and gene conversion during extrachromosomal DNA recombination in cultured animal cells].  

PubMed

For determination of the extrachromosomal homologous DNA recombination efficiency, somatic cells of various lines have been transformed with plasmid DNAs which contain copies of neo-gene with non-overlapping deletions. Reconstruction of the neo-gene functional activity, which imparts a geneticin-resistant phenotype to cells, indicates that recombination has occurred. If dP1 and dR copies of the neo-gene are used, a single (reciprocal) exchange is necessary for reconstruction of the neo-gene by homologous DNA recombination, but a double exchange (gene conversion) is needed in the case of dP1 and dS copies. It is shown that in human cells of line HeLa and in mouse cells of line LMtk-, in contrast to the Chinese hamster cells of line A238, the frequency of double exchanges is comparable to that of the single DNA exchanges which is an evidence of participation in DNA recombination of gene conversion in addition to a single exchange mechanism. The treatment of cells with sodium butyrate and luminol exerts different influences on the rate of the single DNA exchanges and on that of gene conversion (double exchanges) in cells of lines LMtk- and HeLa, respectively. Essential distinctions in correlation of the single DNA exchange frequency and the gene conversion frequency in cells of the studied lines, and the possibility to distinguish between these mechanisms of recombination, under the treatment by sodium butyrate and luminol, may suggest the existence of two mechanisms of homologous DNA recombination in cultured animal cells, which function independently of one another, to a considerable extent. PMID:7809980

Glebov, O K; Abramian, D S; Romanov, S R; Smagina, L V

1994-01-01

334

A novel flow-injection chemiluminescence method for determination of andrographolide in andrographis tablets.  

PubMed

A novel method for determination of andrographolide using flow-injection chemiluminescence (FI-CL) analysis is described in this paper. The chemiluminescence intensity of the solution was enhanced proportionally while the concentration of andrographolide increased. Under the selected experimental conditions, the calibration curve of andrographolide was linear within the range of 0.2 to 35.0 µg mL(-1) with a linear equation of ?I = 23.391x (µg mL(-1)) + 34.191, R(2) = 0.9965. The detection limit (3?) was 7.42 × 10(-2) µg mL(-1). At the case of continuous determination of andrographolide, the relative standard deviation (RSD, n =11) was less than 1.82%. The method has been successfully applied to the determination of andrographis tablets with satisfactory results. PMID:22517683

Jiang, Zejun; Hao, Zaibin; Wu, Qiong; Li, Yang; Liu, Hongyan; Yan, Li

2013-05-01

335

Design of acridinium-9-carboxamides and anti-acridinium antibodies for chemiluminescent signal enhancement.  

PubMed

A novel system of signal enhancement is presented in which every labeled antibody is capable of generating a signal. Three chemiluminescent acridinium-9-carboxamide haptens (1, 2, and 3) which incorporated differences in charge and location of the linker were designed and synthesized. Anti-acridinium polyclonal antibodies for each hapten were screened using surface plasmon resonance instrumentation to determine specificity for each hapten. Anti-acridinium 2 antibodies were found to be non-cross-reactive to acridinium 1. This property was exploited to design secondary antibody conjugates which would bind to primary antibodies labeled with 2 yet could still be labeled with the structurally similar acridinium 1. Consequently, both layers contributed to the overall chemiluminescent signal. This format is an advance over other signal amplification formats which employ non-signal-generating, labeled antibodies to construct multilayered systems. PMID:11353528

Adamczyk, M; Mattingly, P G; Moore, J A; Pan, Y; Shreder, K; Yu, Z

2001-01-01

336

Use of gas-surface chemiluminescence analyzer for NO and NO sub 2 measurements in combustion  

SciTech Connect

This paper reports on a gas-surface NO{sub 2} chemiluminescent analyzer developed for atmospheric measurements of NO{sub 2} which has been adapted for the first time to measure NO and NO{sub 2} in flames. Its substantial advantages compared with the traditional gas-phase chemiluminescent NO analyzers are (1) direct determinations of NO{sub 2} concentrations, (2) an {approx} 10-fold increase in time response and (3) an {approx}1000 fold-increase in sensitivity. Its primary disadvantage is the need for quantitative sample dilution if the NO concentration is greater than 200 ppb. Its application in laminar premixed flames at atmospheric and elevated pressures are demonstrated.

Drake, M.C.; Ratcliffe, J.W. (Physical Chemistry Dept., General Motors Research Lab., Warren, MI (US))

1991-11-01

337

Chemiluminescence detection of glucose using Ce(IV) oxidation in a batch system.  

PubMed

A chemiluminescence method for the determination of glucose (GC) using a batch system made in our laboratory is proposed. The method is based on measures of the chemiluminesence intensity from a batch of sample GC solutions following the injection of an (NH(4))(2)[Ce(NO(3))(6)]-[Ru(bpy)(3)]Cl(2) solution. The effect of the Ru complex concentration on chemiluminescence was studied. The detection limit was 0.5 × 10(-8) M, and the linear calibration curve reached 10(-7) M. The Ru complex was selected on the basis of its desirable performance compared to those of other photosensitizers. However, flow-injection analysis (FIA) using the Ce-Ru complex reagent was not applicable for the detection of GC. PMID:23303079

Nagai, Megumi; Miyahara, Wakayo; Sagawa, Honami; Yamazaki, Shigeo; Saito, Keiitsu

2013-01-01

338

Immune complex transfer two-site chemiluminescent immunoassay for serum growth hormone in alevin chum salmon.  

PubMed

An immune complex transfer two-site chemiluminescent immunoassay (CLIA) for salmon growth hormone (GH) was developed to measure serum GH in alevin chum salmon (Oncorhynchus keta) using a chemiluminescent acridinium ester as a label. The immune complex transfer method dramatically reduced non-specifically bound of acridinium ester labelled antibody without a decrease in the specific binding. Consequently, we could detect lower levels of GH than achieved previously in a two-site CLIA for salmon GH. The detection limit of the assay was 7.8 fg/ml and the standard curve was linear up to 250 fg/ml. Coefficients of variation were 2.2-7.7% within-assay and 5.3-91% between-assay. We have developed a highly sensitive and reproducible GH method and applied it to measurement of GH in alevin chum salmon. PMID:9633014

Fukada, H; Ban, M; Chiba, H; Hara, A

1998-01-01

339

A high throughput chemiluminescence method for determination of chemical oxygen demand in waters  

Microsoft Academic Search

A novel and high throughput chemiluminescence (CL) method for determination of chemical oxygen demand (COD) in water sample was originally developed based on potassium permanganate–glutaraldehyde CL system. With this method, dissolved organic matter in water samples was digested by excess acid potassium permanganate, the reacted mixture solutions containing surplus KMnO4 were added in wells of a 96-well plate, followed by

Hong Yao; Bin Wu; Haibin Qu; Yiyu Cheng

2009-01-01

340

Chemiluminescence system for automatic determination of chemical oxygen demand using flow injection analysis  

Microsoft Academic Search

A novel chemiluminescence (CL) system for automatic determination of chemical oxygen demand (COD) combined with flow injection analysis is proposed in this paper. In this system, potassium permanganate is reduced to Mn2+ which is first adsorbed on a strongly acid cation-exchange resin mini-column to be concentrated during chemical oxidation of the organic compounds at room temperature, while the excessive MnO4?

Baoxin Li; Zhujun Zhang; Juan Wang; Chunli Xu

2003-01-01

341

Sensitive detection of polynucleotide kinase using rolling circle amplification-induced chemiluminescence.  

PubMed

We develop a new method for the sensitive detection of polynucleotide kinase (PNK) using rolling circle amplification-induced chemiluminescence. This method exhibits high sensitivity with a detection limit of 2.20 × 10(-4) U mL(-1), which is superior to most reported approaches. Moreover, this method can be used to screen both the inhibitors and the activators of PNK, and can be further applied for real sample analysis. PMID:24681834

Tang, Wei; Zhu, Guichi; Zhang, Chun-yang

2014-05-11

342

Analysis of Cationic Surfactants in Household Products by High Performance Liquid Chromatography with Nitrogen Chemiluminescence Detection  

Microsoft Academic Search

For compounds containing less than 10% (wt.\\/wt.) nitrogen, the sensivity of nitrogen chemiluminescence detection is limited to concentrations of greater than 0.1 mg\\/mL under typical operating conditions. For determinations of nitrogen containing surfactants in household products, such sensitivity is not prohibitive due to the high levels of surfactant added to the formulations and is potentially offset by the advantage of

Jennifer Truchan; Henrik T. Rasmussen; Nicholas Omelczenko; Bruce P. McPherson

1996-01-01

343

In situ measurements of stratospheric nitric oxide using a balloon-borne chemiluminescent instrument  

Microsoft Academic Search

In situ nitric oxide mixing ratio measurements were made under high sunlight conditions in the stratosphere over New Mexico (17-30.5 km) using balloon-borne chemiluminescent instrumentation. An increase in mixing ratio with height was observed, with NO mixing ratios ranging from 0.15 ppM at 21.28 km to 3.0 ppM at 30.54 km. No serious sampling errors were encountered either from contamination

B. A. Ridley; H. I. Schiff; A. Shaw; L. R. Megill

1975-01-01

344

A fast chemiluminescent method for H 2O 2 measurement in exhaled breath condensate  

Microsoft Academic Search

Background: Breath condensate can give useful information on volatile compounds produced at alveolar level. Actual concentration of H2O2 in breath condensate is dependent on its production at alveolar level and on the efficacy of the detoxifying systems, catalase, glutathione peroxidase, etc. Methods: In the present paper, a simple chemiluminescent method for the determination of the H2O2 collected in exhaled breath

Bruno Zappacosta; Silvia Persichilli; Flaminio Mormile; Angelo Minucci; Andrea Russo; Bruno Giardina; Pasquale De Sole

2001-01-01

345

Time course of superoxide generation by leukocytes—The MCLA chemiluminescence system  

Microsoft Academic Search

This study was performed to examine the pattern of Superoxide (O2-·) generation from leukocytes using the O2-· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O2-· generation by leukocytes. The time course of O2-· generation obtained

László Prónai; Hiroe Nakazawa; Kohji Ichimori; Yoshinori Saigusa; Tomoichi Ohkubo; Kazuko Hiramatsu; Shigeru Arimori; János Fehér

1992-01-01

346

Characterization of thermo-oxidative stability of polymer optical fibers using chemiluminescence technique  

Microsoft Academic Search

The thermo-oxidative stability of commercially available polymer optical fibers (POFs) and their components (cores and claddings) was investigated. All the bare POFs (core and cladding only) studied here were based on poly(methyl methacrylate) (PMMA) core. The fibers were exposed to 100°C\\/low humidity for about 4200h. Chemiluminescence (CL) technique was applied to investigate the thermo-oxidative stability and for measuring the transmission

Anilkumar Appajaiah; Volker Wachtendorf; Werner Daum

2006-01-01

347

Inkjet nanoinjection for high-thoughput chemiluminescence immunoassay on multicapillary glass plate.  

PubMed

We report a novel chemiluminescence diagnosis system for high-throughput human IgA detection by inkjet nanoinjection on a multicapillary glass plate. As proof-of-concept, microhole-based polydimethylsiloxane (PDMS) sheets were aligned on a multicapillary glass plate to form a microwell array as microreactors for enzyme-linked immunosorbent assay (ELISA). The multicapillary glass plate was utilized as a switch that controlled the holding/passing of the solution. Further, anti-IgA-labeled polystyrene (PS) microbeads was assembled into the microwell array, and an inkjet nanoinjection was specially used to distribute the sample and reagent solution for chemiluminescence ELISA, enabling high-throughput detection of human IgA. As a result, the performance of human IgA tests revealed a wider range for the calibration curve and a lower limit of detection (LOD) of 0.1 ng mL(-1) than the ELISA by a standard 96-well plate. The analysis time and reagent consumption were significantly decreased. The IgA concentrations in saliva samples were determined after 10000-fold dilution by the developed ELISA system showing comparable results by conventional immune assay with 96-wells. Thus, we believe that the inkjet nanoinjection for high-throughput chemiluminescence immunoassay on a multicapillary glass plate will be promising in disease diagnosis. PMID:23815610

Chen, Fengming; Mao, Sifeng; Zeng, Hulie; Xue, Shuhua; Yang, Jianmin; Nakajima, Hizuru; Lin, Jin-Ming; Uchiyama, Katsumi

2013-08-01

348

Chemiluminescence-based pesticide biosensor utilizing the intelligent evolved properties of the enzyme alkaline phosphatase  

SciTech Connect

A methodology is described for immobilizing the enzyme alkaline phosphatase onto a glass surface using a novel biotinylated copolymer, poly(3-undecylthiophene-co-3- methanoithiophene). A streptavidin conjugate of alkaline phosphatase is used in this study. The biotinylated polymer is attached to the silanized glass surface via hydrophobic interactions and the enzyme is interfaced with the polymer through the classical biotin- streptavidin interaction. Alkaline phosphatase catalyzes the dephosphorylation of a macrocyclic compound, chloro-3-(4-methoxy spiro) (1,2 dioxetane-3-2`-tricyclo-) (3.3.1.1 )-(decani-4-yl) phenyl phosphate, to a species which emits energy by chemiluminescence. This chemiluminescence signal can be detected with a photomultiplier tube for enzymatic catalysis with the biocatalyst both in solution and immobilized on a glass surface. The signal generation is inhibited by the organophosphorus based insecticides such as paraoxon as well as nerve agents. We demonstrate in this study that a number of organophosphorus based insecticides inhibit the enzyme-mediated generation of chemiluminescence signal. This is true for the enzyme conjugate both free in solution and immobilized on a glass surface. In solution, the inhibition resembles the case of a partially uncompetitive system. By this type of inhibition we are able to detect pesticides down to about 50 ppb for the enzyme in solution. The pesticide detection limit of immobilized enzyme is currently being investigated. The enzyme is capable of a number of measurement cycles without significant loss of signal level.

Ayyagari, M.; Kamtekar, S.; Pande, R.; Marx, K.; Kumar, J.

1994-12-31

349

Chemiluminescence measurements on irradiated garlic powder by the single photon counting technique  

NASA Astrophysics Data System (ADS)

The feasibility of identifying irradiated garlic powder measuring chemiluminescence by liquid scintillation spectrometry was studied. Samples packed in 100 ?m thick polyethylene bags were irradiated in a 60Co semi-industrial facility, with doses of 10 and 30 kGy. Control and irradiated samples were stored at 20 ± 4°C and 70 ± 10% RH in darkness for 2 years. Assays were performed to establish the best sample concentration and pH of the buffer solution in which garlic powder was to be suspended for its measurement. The water content of garlic samples was also analyzed throughout storage time, as it related to the stability of the species causing luminescence. Chemiluminescence values diminished in every sample over storage time following an exponential pattern. Irradiated samples showed values significantly higher than those of the control samples, according to the radiation dose, throughout the storage period. This does not necessarily imply that the identification of the irradiated samples would be certain, since values of control samples coming from different origins have been found to fluctuate within a rather wide range. Nonetheless, in principle, the method looks promising for the measurement of chemiluminescence in irradiated samples

Narvaiz, P.

1995-02-01

350

Analysis of chemiluminescence measurements by grey-scale ICCD and colour digital cameras  

NASA Astrophysics Data System (ADS)

Spectral, grey-scale and colour chemiluminescence measurements of C2* and CH* radicals' emission are carried out on the flame front of a methane-air premixed flame at different equivalence ratios. To this purpose, properly spatially resolved optical equipment has been implemented in order to reduce the background emission from other burned gas regions. The grey-scale (ICCD + interference filters) and RGB colour (commercial digital camera) approaches have been compared in order to find a correspondence between the C2* and the green component, as well as the CH* and the blue component of the emission intensities. The C2*/CH* chemiluminescence ratio has been investigated at different equivalence ratios and a good correlation has been obtained, showing the possibility of sensing the equivalence ratio in practical systems. The grey-scale and colour chemiluminescence analysis has then been applied to a meso-scale not premixed swirl combustor fuelled with a methane-air mixture and operating at 0.3 MPa. 2D results are presented and discussed in this work.

Migliorini, F.; Maffi, S.; De Iuliis, S.; Zizak, G.

2014-05-01

351

Development of ultrasensitive direct chemiluminescent enzyme immunoassay for determination of aflatoxin M1 in milk.  

PubMed

A direct competitive chemiluminescent enzyme-linked immunosorbent assay (CL-ELISA) for detecting aflatoxin M1 (AFM1) was developed. To improve the sensitivity of the assay, a mixture of 3-(10'-phenothiazinyl)-propane-1-sulfonate (SPTZ) and 4-morpholinopyridine (MORPH) was used to enhance peroxidase-induced CL. The concentrations of the coating anti-AFM1 antibody and the conjugate of AFB1 with horseradish peroxidase the conditions of the chemiluminescent assay were varied to optimise the condition of the chemiluminescent assay. The lower detection limit values and dynamic working range of CL-ELISA of AFM1 were 0.001 ng mL(-1) and 0.002-0.0075 ng mL(-1), respectively. A 20-fold dilution of milk samples prevented a matrix effect of the milk and allowed measurement of AFM1 at concentrations below than the maximum acceptable limit. Values of recovery within and between assays were 81.5-117.6% and 86-110.6%, respectively. The results of using the developed CL-ELISA to analyse samples of six brands of milk that were purchased in Taiwan revealed that AFM1 was absent from all studied samples. PMID:24731347

Vdovenko, Marina M; Lu, Chuan-Chen; Yu, Feng-Yih; Sakharov, Ivan Yu

2014-09-01

352

Chemiluminescent examination of abiotic oxidative stress of watercress.  

PubMed

Watercress (Nasturtium officinale) is an aquatic plant that readily bioaccumulates heavy metals that may be found in contaminated aquatic systems. Toxic effects of contaminants on the physiological processes cause changes in oxidase enzymatic activity in watercress, which can be measured with a luminometer. The luminometer uses the reaction produced when peroxidases break down hydrogen peroxide into water and an oxygen radical. The resulting oxyradical binds to and oxidizes phenolic groups, producing a measureable luminescent reaction. Nasturtium officinale plants were exposed to 3 different concentrations of heavy metals, including lead, nickel, copper, and manganese for 24 h, 48 h, and 72 h. Aquatic exposure to the 4 heavy metals caused a significant increase in oxidative enzyme production. Fluorometric and morphometric measurements were also conducted to compare plant stress with the oxidative enzyme analyses. Fluorometric measurements performed on plants stressed by exposure to heavy metals revealed no significant decreases in photosystem II efficiency. Morphometric measurements of root length showed decreased root growth resulting from exposures to Ni, Cu, and Mn. PMID:24306856

Beals, Christopher; Byl, Thomas

2014-04-01

353

Flow-injection chemiluminescence determination of acetylsalicylic acid based on its enhancing effect on the lucigenin–hydrogen peroxide system.  

PubMed

A sensitive flow-injection chemiluminescence method for the determination of acetylsalicylic acid is described. It is based on the enhanced chemiluminescent emission of the alkaline lucigenin–H2O2 system by acetylsalicylic acid. The difference in chemiluminescent intensity of alkaline lucigenin–H2O2 in the presence of acetylsalicylic acid from that in the absence of acetylsalicylic acid was linear at acetylsalicylic acid concentrations in the range of 0.0029–47.37 ?g/mL, with detection and quantification limits of 0.0011 and 0.0029 ?g/mL, respectively. The correlation coefficient of the working curve was 0.9983. The relative standard deviation (n = 10) for 25 ?g/mL acetylsalicylic acid is 1.95%. All experimental parameters were optimized. The method was successfully applied to the determination of acetylsalicylic acid in pharmaceutical preparations. The recovery results obtained by the method were satisfactory. PMID:25337618

Wabaidur, S M; Alam, S M; Alothmana, Z A; Eldesokya, Gaber

2014-09-01

354

Toward complete miniaturisation of flow injection analysis systems: microfluidic enhancement of chemiluminescent detection.  

PubMed

Conventional flow injection systems for aquatic environmental analysis typically comprise large laboratory benchscale equipment, which place considerable constraints for portable field use. Here, we demonstrate the use of an integrated acoustically driven microfluidic mixing scheme to enhance detection of a chemiluminescent species tris(2,2'-bipyridyl)dichlororuthenium(II) hexahydrate-a common chemiluminescent reagent widely used for the analysis of a wide range of compounds such as illicit drugs, pharmaceuticals, and pesticides-such that rapid in-line quantification can be carried out with sufficient on-chip sensitivity. Specifically, we employ surface acoustic waves (SAWs) to drive intense chaotic streaming within a 100 ?L chamber cast in polydimethoxylsiloxane (PDMS) atop a microfluidic chip consisting of a single crystal piezoelectric material. By optimizing the power, duration, and orientation of the SAW input, we show that the mixing intensity of the sample and reagent fed into the chamber can be increased by one to two orders of magnitude, leading to a similar enhancement in the detection sensitivity of the chemiluminescent species and thus achieving a theoretical limit of detection of 0.02 ppb (0.2 nM) of l-proline-a decade improvement over the industry gold-standard and two orders of magnitude more sensitive than that achievable with conventional systems-simply using a portable photodetector and without requiring sample preconcentration. This on-chip microfluidic mixing strategy, together with the integrated miniature photodetector and the possibility for chip-scale microfluidic actuation, then alludes to the attractive possibility of a completely miniaturized platform for portable field-use microanalytical systems. PMID:25275830

Gracioso Martins, Ana M; Glass, Nick R; Harrison, Sally; Rezk, Amgad R; Porter, Nichola A; Carpenter, Peter D; Du Plessis, Johan; Friend, James R; Yeo, Leslie Y

2014-11-01

355

Attenuation of tumor necrosis factor-induced endothelial cell cytotoxicity and neutrophil chemiluminescence  

SciTech Connect

Our laboratory has previously shown that the administration of tumor necrosis factor (TNF), a cytokine produced by activated mononuclear cells, to guinea pigs produces a syndrome similar to gram-negative sepsis or ARDS. Pentoxifylline (PTX), a methylxanthine, protects against TNF-induced and sepsis-induced acute lung injury in vivo. We now report on in vitro cellular studies of PMN-mediated cellular injury and its attenuation. We studied TNF-induced bovine pulmonary artery endothelial cell (EC) cytotoxicity both with and without PMN. A 51Cr release assay was used to measure EC damage. Further, we investigated PMN function in response to TNF by measuring chemiluminescence. Agents that attenuate EC damage and PMN activation were evaluated in the above assays. Results revealed that TNF causes EC injury (p less than 0.05) and PMN increase TNF-induced EC injury. Furthermore, PTX, aminophylline (AMPH), caffeine, and forskolin attenuate TNF-induced EC cytotoxicity only in the presence of PMN (p less than 0.05). Of interest, dibutyryl cAMP (DBcAMP) protects EC from TNF-induced injury both with and without PMN. Agents that may increase cAMP levels in PMN (PTX, DBcAMP, forskolin, isobutyl methylxanthine, and terbutaline) significantly attenuate TNF-induced PMN chemiluminescence (p less than 0.05). We conclude that TNF causes EC damage and PMN increase this damage. Furthermore, PTX, AMPH, caffeine, and forskolin can attenuate TNF-induced EC injury in the presence of PMN, whereas DBcAMP attenuates TNF-induced EC injury with and without PMN. In addition, agents that may increase intracellular cAMP levels in PMN can attenuate TNF-induced PMN chemiluminescence. Thus, these agents likely attenuate TNF-induced PMN-mediated EC injury through their inhibitory effects on PMN.

Zheng, H.; Crowley, J.J.; Chan, J.C.; Hoffmann, H.; Hatherill, J.R.; Ishizaka, A.; Raffin, T.A. (Stanford Univ. Medical Center, CA (USA))

1990-11-01

356

Thermal chemiluminescence from ?-irradiated polytetrafluoroethylene and its emission mechanism: Investigation by multichannel Fourier-transform luminescence spectroscopy  

NASA Astrophysics Data System (ADS)

Thermal chemiluminescence spectra of polytetrafluoroethylene powder irradiated by ? rays in air at room temperature were measured with a multichannel Fourier-transform chemiluminescence spectrometer. The luminescence appeared immediately after heating the irradiated samples at 160, 180 and 200 °C in dry air and in N2 and then disappeared within a few minutes, whereas virgin samples showed no luminescence. The lifetime of luminescence decreased as the heating temperature increased, but the total amount of luminescence at each temperature was nearly constant. From this observation an emission mechanism was derived with the aid of ESR and IR spectroscopy.

Noguchi, Tsuyoshi; Yamada, Emi; Akai, Nobuyuki; Ishii, Hiroshi; Satoh, Chikahiro; Hironiwa, Takayuki; Millington, Keith R.; Nakata, Munetaka

2014-10-01

357

Molecular assembly of multilayer enzyme on fiber optic surface: toward the development of chemiluminescence-based fiber optic biosensors  

NASA Astrophysics Data System (ADS)

We report here on a technique to immobilize a multilayer enzyme assembly on an optic fiber surface. A multilayer of an enzyme, alkaline phosphatase, was successfully immobilized on an optical fiber surface. Chemiluminescence, ellipsometry, and surface plasmon resonance were used to characterize the structure and activity of the assembly. A chemiluminescence-based fiber optic biosensor utilizing this immobilization technique has been developed for the detection of organophosphorous-based pesticides. Detection of pesticide at sub-ppm level has been achieved for paraoxon.

Chen, Zhongping; Gao, Harry H.; Kumar, Jayant; Marx, Kenneth A.; Tripathy, Sukant K.; Kaplan, David L.

1996-04-01

358

A review of recent advances in chemiluminescence detection using nano-colloidal manganese(IV).  

PubMed

The application of 'soluble' (colloidal) manganese(IV) for chemiluminescence detection is reviewed, focussing on papers published since the last comprehensive review of the subject in 2008. Advances in this reagent system include: the on-line formation of manganese(IV); new insight into the light-producing pathway and selectivity of the reagent; its application to assess total antioxidants in plant derived samples and oxidative stress in biological fluids and tissues; and the replacement of the formaldehyde enhancer with ethanol. PMID:25263111

Adcock, Jacqui L; Smith, Zoe M; Barnett, Neil W; Barbante, Gregory J; Doeven, Egan H; Francis, Paul S

2014-10-27

359

Ultrasensitive detection of cancer cells and glycan expression profiling based on a multivalent recognition and alkaline phosphatase-responsive electrogenerated chemiluminescence biosensor  

NASA Astrophysics Data System (ADS)

A multivalent recognition and alkaline phosphatase (ALP)-responsive electrogenerated chemiluminescence (ECL) biosensor for cancer cell detection and in situ evaluation of cell surface glycan expression was developed on a poly(amidoamine) (PAMAM) dendrimer-conjugated, chemically reduced graphene oxide (rGO) electrode interface. In this strategy, the multivalency and high affinity of the cell-targeted aptamers on rGO provided a highly efficient cell recognition platform on the electrode. The ALP and concanavalin A (Con A) coated gold nanoparticles (Au NPs) nanoprobes allowed the ALP enzyme-catalyzed production of phenols that inhibited the ECL reaction of Ru(bpy)32+ on the rGO electrode interface, affording fast and highly sensitive ECL cytosensing and cell surface glycan evaluation. Combining the multivalent aptamer interface and ALP nanoprobes, the ECL cytosensor showed a detection limit of 38 CCRF-CEM cells per mL in human serum samples, broad dynamic range and excellent selectivity. In addition, the proposed biosensor provided a valuable insight into dynamic profiling of the expression of different glycans on cell surfaces, based on the carbohydrates recognized by lectins applied to the nanoprobes. This biosensor exhibits great promise in clinical diagnosis and drug screening.A multivalent recognition and alkaline phosphatase (ALP)-responsive electrogenerated chemiluminescence (ECL) biosensor for cancer cell detection and in situ evaluation of cell surface glycan expression was developed on a poly(amidoamine) (PAMAM) dendrimer-conjugated, chemically reduced graphene oxide (rGO) electrode interface. In this strategy, the multivalency and high affinity of the cell-targeted aptamers on rGO provided a highly efficient cell recognition platform on the electrode. The ALP and concanavalin A (Con A) coated gold nanoparticles (Au NPs) nanoprobes allowed the ALP enzyme-catalyzed production of phenols that inhibited the ECL reaction of Ru(bpy)32+ on the rGO electrode interface, affording fast and highly sensitive ECL cytosensing and cell surface glycan evaluation. Combining the multivalent aptamer interface and ALP nanoprobes, the ECL cytosensor showed a detection limit of 38 CCRF-CEM cells per mL in human serum samples, broad dynamic range and excellent selectivity. In addition, the proposed biosensor provided a valuable insight into dynamic profiling of the expression of different glycans on cell surfaces, based on the carbohydrates recognized by lectins applied to the nanoprobes. This biosensor exhibits great promise in clinical diagnosis and drug screening. Electronic supplementary information (ESI) available: CV and EIS during the electrode assembly, activity of the nanoprobes and the glycan-binding specificities of the lectins. See DOI: 10.1039/c4nr03053b

Chen, Xiaojiao; He, Yao; Zhang, Youyu; Liu, Meiling; Liu, Yang; Li, Jinghong

2014-09-01

360

Microplate-reader method for the rapid analysis of copper in natural waters with chemiluminescence detection  

PubMed Central

We have developed a method for the determination of copper in natural waters at nanomolar levels. The use of a microplate-reader minimizes sample processing time (~25 s per sample), reagent consumption (~120 ?L per sample), and sample volume (~700 ?L). Copper is detected by chemiluminescence. This technique is based on the formation of a complex between copper and 1,10-phenanthroline and the subsequent emission of light during the oxidation of the complex by hydrogen peroxide. Samples are acidified to pH 1.7 and then introduced directly into a 24-well plate. Reagents are added during data acquisition via two reagent injectors. When trace metal clean protocols are employed, the reproducibility is generally less than 7% on blanks and the detection limit is 0.7 nM for seawater and 0.4 nM for freshwater. More than 100 samples per hour can be analyzed with this technique, which is simple, robust, and amenable to at-sea analysis. Seawater samples from Storm Bay in Tasmania illustrate the utility of the method for environmental science. Indeed other trace metals for which optical detection methods exist (e.g., chemiluminescence, fluorescence, and absorbance) could be adapted to the microplate-reader. PMID:23335917

Durand, Axel; Chase, Zanna; Remenyi, Tomas; Queroue, Fabien

2013-01-01

361

Exhaled nitric oxide monitoring by quantum cascade laser: comparison with chemiluminescent and electrochemical sensors  

NASA Astrophysics Data System (ADS)

Fractional exhaled nitric oxide (FENO) is considered an indicator in the diagnostics and management of asthma. In this study we present a laser-based sensor for measuring FENO. It consists of a quantum cascade laser (QCL) combined with a multi-pass cell and wavelength modulation spectroscopy for the detection of NO at the sub-part-per-billion by volume (ppbv, 1?10-9) level. The characteristics and diagnostic performance of the sensor were assessed. A detection limit of 0.5 ppbv was demonstrated with a relatively simple design. The QCL-based sensor was compared with two market sensors, a chemiluminescent analyzer (NOA 280, Sievers) and a portable hand-held electrochemical analyzer (MINO®, Aerocrine AB, Sweden). FENO from 20 children diagnosed with asthma and treated with inhaled corticosteroids were measured. Data were found to be clinically acceptable within 1.1 ppbv between the QCL-based sensor and chemiluminescent sensor and within 1.7 ppbv when compared to the electrochemical sensor. The QCL-based sensor was tested on healthy subjects at various expiratory flow rates for both online and offline sampling procedures. The extended NO parameters, i.e. the alveolar region, airway wall, diffusing capacity, and flux were calculated and showed a good agreement with the previously reported values.

Mandon, Julien; Högman, Marieann; Merkus, Peter J. F. M.; van Amsterdam, Jan; Harren, Frans J. M.; Cristescu, Simona M.

2012-01-01

362

Amorphous carbon nanoparticle used as novel resonance energy transfer acceptor for chemiluminescent immunoassay of transferrin.  

PubMed

Amorphous carbon nanoparticles (ACNPs) showing highly efficient quenching of chemiluminescence (CL) were prepared from candle soot with a very simple protocol. The prepared ACNP was employed as the novel energy acceptor for a chemiluminescence resonance energy transfer (CRET)-based immunoassay. In this work, ACNP was linked with transferrin (TRF), and horseradish peroxidase (HRP) was conjugated to TRF antibody (HRP-anti-TRF). The immunoreaction rendered the distance between the ACNP acceptor and the HRP-catalyzed CL emitter to be short enough for CRET occurring. In the presence of TRF, this antigen competed with ACNP-TRF for HRP-anti-TRF, thus led to the decreased occurrence of CRET. A linear range of 20-400 ng mL(-1) and a limit of detection of 20 ng mL(-1) were obtained in this immunoassay. The proposed method was successfully applied for detection of TRF levels in human sera, and the results were in good agreement with ELISA method. Moreover, the ACNPs show higher energy transfer efficiency than other conventional nano-scaled energy acceptors such as graphene oxide in CRET assay. It is anticipated that this approach can be developed for determination of other analytes with low cost, simple manipulation and high specificity. PMID:24636417

Gao, Hongfei; Wang, Wenwen; Wang, Zhenxing; Han, Jing; Fu, Zhifeng

2014-03-28

363

COMPARATIVE ASSESSMENT OF QUALITY OF IMMUNORADIOMETRIC ASSAY (IRMA) AND CHEMILUMINESCENCE IMMUNOMETRIC ASSAY (CHEIMA) FOR ESTIMATION OF THYROID STIMULATING HORMONE (TSH)  

Microsoft Academic Search

Biological substances like hormones, vitamins and enzymes are found in minute quantities in blood. Their estimation requires very sensitive and specific methods. The most modern method for estimation of thyroid stimulating hormone in serum is non-isotopic enzyme enhanced chemiluminescence immunometric method. In our laboratory immunoradiometric assay is in routine for the last many years. Recently interest has grown to establish

K. M. SAJID

364

NO sub X destruction by CO in NO sub X to NO converters of chemiluminescent NO analyzers  

NASA Technical Reports Server (NTRS)

An instrument modification for chemiluminescent NO - NOx analyzers was developed which minimizes the NOx destruction in the NOx to NO converters of NO analyzers due to high concentrations of CO. This mechanism causes the NO analyzers to indicate incorrect NOx concentrations when the analyzers are operated in the NOx analysis mode. The modification is applicable to analyzers in which the detection chamber is evacuated.

Summers, R. L.

1976-01-01

365

Ray tracing of chemiluminescence in an unconfined non-premixed turbulent jet flame using large-eddy simulation  

NASA Astrophysics Data System (ADS)

Optical diagnostic techniques, such as chemiluminescence imaging, are commonly used to study turbulent flames. Inherent to turbulent flames is the spatio-temporal variation of the volumetric distribution of temperature and chemical composition. In consequence, the index of refraction varies accordingly and causes distortion of any optical ray intersecting the turbulent flame. This distortion is well known as beam steering. Beam steering may degrade imaging quality by reducing the overall spatial resolution. Its impact of course depends on the actual specifications of the imaging system itself. In this study a methodology is proposed to tackle this issue numerically and is exemplified for chemiluminescence imaging in a well-known turbulent hydrogen-fueled jet flame. Large-eddy simulation (LES) of this unconfined non-premixed flame is used to simulate instantaneous volumetric distributions of the flow and scalar fields including the local index of refraction. This simulation additionally predicts local concentrations of electronically excited chemiluminescent active species. At locations with significantly high concentrations of luminescent species, optical rays are initiated in the direction of the array detector used for recording single chemiluminescence images. Assuming the validity of geometrical optics, these rays are tracked along their pathways. Their direction of propagation changes according to the local instantaneous distribution of the index of refraction. After leaving the computational domain of the ray tracing code which is fed by the LES, each ray is processed by the commercial code ZEMAX® and imaged onto an array detector. Measured and numerically simulated ensemble-averaged chemiluminescence images are compared to each other. Overall, a satisfying agreement is observed. The primary aim of this paper is the exposition of this method where numerical and experimental results are not any more compared in the flame but where this comparison is shifted to the imaging plane. Future extensions to higher pressures in enclosed combustors or internal combustion engines where beam-steering effects are much more pronounced than in atmospheric jet flames are addressed.

Ertem, C. K.; Janicka, J.; Dreizler, A.

2012-06-01

366

Reactions & Rates  

NSDL National Science Digital Library

Explore what makes a reaction happen by colliding atoms and molecules. Design experiments with different reactions, concentrations, and temperatures. When are reactions reversible? What affects the rate of a reaction?

Simulations, Phet I.; Koch, Linda; Lemaster, Ron; Loeblein, Trish; Perkins, Kathy; Gratny, Mindy

2006-12-01

367

Eignung von Thermolumineszenz-, Chemilumineszenz-, ESR- und Viskositaetsmessungen zur Identifizierung strahlenbehandelter Arzneidrogen. (Suitability of thermoluminescence, chemiluminescence, ESR and viscosity measurements as detection method for the irradiation of medicinal herbs).  

National Technical Information Service (NTIS)

Chemiluminescence, electron spin resonance, thermoluminescence and viscosity measurements have been investigated for their suitability as detection method for the irradiation of the medicinal herbs anise seeds (anisi fructus), valerian roots (valerianae r...

C. Schuettler, G. Gebhardt, A. Stock, N. Helle, K. W. Boegl

1993-01-01

368

Ultrasensitive detection of cancer cells and glycan expression profiling based on a multivalent recognition and alkaline phosphatase-responsive electrogenerated chemiluminescence biosensor.  

PubMed

A multivalent recognition and alkaline phosphatase (ALP)-responsive electrogenerated chemiluminescence (ECL) biosensor for cancer cell detection and in situ evaluation of cell surface glycan expression was developed on a poly(amidoamine) (PAMAM) dendrimer-conjugated, chemically reduced graphene oxide (rGO) electrode interface. In this strategy, the multivalency and high affinity of the cell-targeted aptamers on rGO provided a highly efficient cell recognition platform on the electrode. The ALP and concanavalin A (Con A) coated gold nanoparticles (Au NPs) nanoprobes allowed the ALP enzyme-catalyzed production of phenols that inhibited the ECL reaction of Ru(bpy)3(2+) on the rGO electrode interface, affording fast and highly sensitive ECL cytosensing and cell surface glycan evaluation. Combining the multivalent aptamer interface and ALP nanoprobes, the ECL cytosensor showed a detection limit of 38 CCRF-CEM cells per mL in human serum samples, broad dynamic range and excellent selectivity. In addition, the proposed biosensor provided a valuable insight into dynamic profiling of the expression of different glycans on cell surfaces, based on the carbohydrates recognized by lectins applied to the nanoprobes. This biosensor exhibits great promise in clinical diagnosis and drug screening. PMID:25123148

Chen, Xiaojiao; He, Yao; Zhang, Youyu; Liu, Meiling; Liu, Yang; Li, Jinghong

2014-09-12

369

Chemiluminescence determination of fluoroquinolones using Fenton system in the presence of terbium(iii) ions.  

PubMed

A simple new chemiluminescent, CL, method is described for the determination of fluoroquinolones such as: ciprofloxacin (CF), norfloxacin (NF), and ofloxacin (OF). This method is based on the measurement of terbium(iii) emission. This emission follows an energy transfer to the uncomplexed terbium(iii) ions from the excited products of fluoroquinolone oxidations. Under optimum conditions, calibration graphs were obtained for 2 × 10(-8)-2 × 10(-6) mol L(-1) of NF; 3 × 10(-8)-2 × 10(-6) mol L(-1) of CF and 4 × 10(-7)-5 × 10(-5) mol L(-1) of OF. The detection limits are 7 × 10(-9) mol L(-1) norfloxacin, 1 × 10(-8) mol L(-1) ciprofloxacin and 1.5 × 10(-7) mol L(-1) ofloxacin. The method was successfully applied to the determination of these drugs in pharmaceutical formulations. PMID:21519592

Kaczmarek, Ma?gorzata; Lis, Stefan

2011-06-21

370

Direct chemiluminescence of carbon dots induced by potassium ferricyanide and its analytical application  

NASA Astrophysics Data System (ADS)

The chemiluminescence (CL) of water-soluble fluorescent carbon dots (C-dots) induced by direct chemical oxidation was investigated. C-dots were prepared by solvothermal method and characterized by fluorescence spectra and transmission electron microscopy. It was found that K3Fe(CN)6 could directly oxidize C-dots to produce a relatively intense CL emission. The mechanism of CL generation was investigated based on the fluorescence and CL emission spectra and the effect of radical scavengers on the CL intensity. The inhibitive effect of some metal ions and biologically important molecules on the CL intensity of the system was examined and the potential of the system for the determination of these species at trace levels was studied. In order to evaluate the capability of method to real sample analysis, it was applied to the determination of Cr(VI) and adrenaline in water and injection samples, respectively.

Amjadi, Mohammad; Manzoori, Jamshid L.; Hallaj, Tooba; Sorouraddin, Mohammad H.

2014-03-01

371

Absolute rate constant for the O plus NO chemiluminescence in the near infrared  

NASA Technical Reports Server (NTRS)

Infrared chemiluminescence from the process O + NO (+M) NO2 + hv (+M) has been studied between 1.3 and 4.1 micrometer. The wavelength dependence of the continuum between 1.3 and 3.3 micrometer is in fair agreement with previous studies and the measured radiative rate constant at 1.51 micrometer establishes the NO-O glow in this spectral range as a secondary emission standard. Comparison with previous studies of the visible region of the glow implies that the overall radiative rate constant lies in the range (9.4 to 11.2) x 10 to the minus 17 power cu cm sec/1. In the region 3.3 to 4.1 micrometer, the previously observed broad band, peaking at 3.7 micrometer, shows a complex kinetic dependence on O and M.

Golde, M. F.; Roche, A. E.; Kaufman, F.

1973-01-01

372

Electrogenerated chemiluminescence of common organic luminophores in water using an emulsion system.  

PubMed

We describe a method to produce electrogenerated chemiluminescence (ECL) in water using a family of highly hydrophobic polycyclic aromatic hydrocarbon (PAH) luminophores and boron dipyrromethene (BODIPY). This method is based on an oil-in-water emulsion system. Various PAHs (rubrene, 9,10-diphenylanthracene, pyrene, or perylene) and BODIPY were trapped in a toluene and tri-n-propylamine mixed oil-in-water emulsion using an ionic liquid as the supporting electrolyte and emulsifier. ECL was observed for all the aforementioned PAHs and BODIPY, and the rubrene and BODIPY emulsion systems showed adequate light to record an ECL spectrum. ECL was also observed using oxalate as the co-reactant, which was dissolved in the aqueous continuous phase. The emulsions were stable for hours and showed a droplet size distribution that ranged from 275 to 764 nm, in accordance with dynamic light scattering data. PMID:25222019

Dick, Jeffrey E; Renault, Christophe; Kim, Byung-Kwon; Bard, Allen J

2014-10-01

373

Development of a Chemiluminescence Method for Gas-Phase HO2 Detection  

NASA Astrophysics Data System (ADS)

Hydroperoxyl Radical (HO2) is a highly reactive intermediate species that participates in photochemical processes in the troposphere. Accurate measurement of HO2 will facilitate the verification of the ozone production mechanism used by the atmospheric chemistry community. HO2 is also the major source of H2O2, which is responsible for the oxidation of SO2 in droplets. Here, we describe a new HO2 detection method based on flow injection analysis (FIA) with a chemiluminescence detector. Gas-phase HO2 is first scrubbed into a pH 9 borax buffer solution, then injected into a chemiluminescence detector, where HO2 and its conjugate base O2- react with MCLA, a synthetic analog of the luciferin from the crustacean Cypridina, to emit light at 465 nm. This technique shows high sensitivity (DL = 0.1 nM in liquid phase or 1 pptv in gas phase) and selectivity for the HO2 / O2- system. A unique feature of our technique is the calibration with a radiolytic method that uses a 60Co gamma ray source to quantitatively produce stable aqueous HO2 / O2- standards. This calibration method is highly reproducible, producing an instrument response that varies less than 5% from day to day. We tested our instrument in the meteorology field at Brookhaven National Laboratory (BNL), which is considered a clean remote rural site with background ozone levels about 30 ppbv. On July 17, 2003, a clear sunny day, with a steady NW wind, HO2 started to build up after sunrise and reached a maximum of 9 pptv at about 3 pm local time, approximately two hours after the maximum solar intensity. Our technique has the advantages of simplicity, low cost and ease of operation. It is especially suitable for field measurements, where space and energy resources are usually limited.

Zheng, J.; Lloyd, J.; Springston, S.

2003-12-01

374

Development of nanobody-based flow injection chemiluminescence immunoassay for sensitive detection of human prealbumin.  

PubMed

Nanobodies, derived from camelid heavy-chain antibodies, have novel and impactful applications in clinical diagnostics. Our objective is to develop a nanobody-based chemiluminescence immunoassay for sensitive detection of human prealbumin (PA). In this context, a phage display nanobody library is constructed via immunizing dromedary camel with human prealbumin. Three nanobodies have been identified by five successive bio-panning steps. Based on their high expression level and good affinity, two out of three are chosen for further study. Magnetic beads (MBs) were functionalized with PEI by acylamide bond formed between the carboxyl group on the surface of the MB. Then, an anti-PA nanobody (Nb1) can be effectively immobilized onto the surface of the functionalized MB using glutaradehyde as the link. The modified MBs with Nb1 can specifically capture the target PA and reacted with silica nanoparticles with co-immobilized HRP and anti-PA nanobody (Nb2). The concentration of PA was detected by flow injection chemiluminescence. When using MB/PEI as the carrier of anti-PA Nb1, the CL signal significantly increased to 4-fold compared with the signal using MB without PEI modification. The CL signal was further amplified to 5-fold when Si/Nb2 was used as the signal probe. Under optimized conditions, the present immunoassay exhibited a wide quantitative range from 0.05 to 1000 ?g L(-1) with a detection limit of 0.01 ?g L(-1). The sensitivity of the proposed immunoassay offers great promises in providing a sensitive, specific, time saving, and potential method for detecting PA in clinical settings. PMID:24874660

Ma, Lei; Sun, Yanyan; Kang, Xuejun; Wan, Yakun

2014-11-15

375

Multianalyte immunoassay chip for detection of tumor markers by chemiluminescent and colorimetric methods.  

PubMed

Most cancers developed an elevation of the level of at least two markers associated with their incidence. Simultaneous detection of multi-tumor markers associated with a particular type of cancer plays an important role in cancer diagnostic. Here, a multianalyte immunoassay chip for simple and sensitive detection of tumor markers with chemiluminescent and colorimetric methods was proposed, in which carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9) that associated with colorectal cancer were detected as model. The immunoassay chip was fabricated by co-immobilization of CEA/CA19-9 antibody on a glass slide with ?-glycidoxypropyltrimethoxysilane as linkage. Through sandwiched immunoreactions, CEA, CA19-9, and their corresponding enzyme tracers, alkaline phosphatase-labeled anti-CEA and horseradish peroxidase-labeled anti-CA19-9, were introduced on the chip. Then, they were sequentially detected by chemiluminescent method in the range of 0.5-80 ?g/L and 0.5-80 kU/L with the detection limits of 0.41 ?g/L and 0.36 kU/L at 3? for CEA and CA19-9, respectively. They could also be detected by colorimetric method in the range of 1-200 ?g/L and 5-200 kU/L with the detection limits of 0.25 ?g/L and 1.25 kU/L at 3? for CEA and CA19-9, respectively. All these results demonstrated that the present work provided a promising analytical method for tumor markers' analysis with the advantages of simple analytical procedure, small sample volume and lower cost, which made the proposed method potential for high-throughput detection. PMID:21928078

Wei, Wei; Zhang, Chunyan; Qian, Jing; Liu, Songqin

2011-12-01

376

Characterization and validation of a chemiluminescent assay based on 1,2-dioxetanes for rapid detection of viable Escherichia coli  

Microsoft Academic Search

[(4-methoxy-4(3-?-d-galactose-4-chlorophenyl)]spiro[1,2-dioxetane-3-1,3-tricyclo[7.3.1.02,7]tridec-2,7-ene] (“s?-Gal 102”) and sodium [4-methoxy-4(3-?-d-glucuronic acid-4-chlorophenyl)]spiro[1,2-dioxetane-3-1,3-tricyclo[7.3.1.02,7]tridec-2,7-ene] (“s?-Glucor 102”) are carbohydrate-containing 1,2-dioxetane compounds that produce chemiluminescence upon\\u000a enzymatic hydrolysis by ?-d-galactosidase, and ?-d-glucuronidase, respectively. In this study, we have characterized and validated a sensitive detection principle for viable\\u000a Escherichia coli based on enzymatic cleavage of s?-Gal 102 and s?-Glucor 102 (“ColiLight II”). The proposed chemiluminescent assay was optimized\\u000a with respect

Annette S. Bukh; Peter Roslev

2010-01-01

377

Stimulatory effect of some plant extracts used in homeopathy on the phagocytosis induced chemiluminescence of polymorphonuclear leukocytes.  

PubMed

Some plant extracts on a large range of dilutions as used in Homeopathy were tested on the chemiluminescence emission produced by polymorphonuclear leukocytes. The high stimulatory action was noticed when extracts from Uvae Ursi and Saponaria were tested, as the classical effect exerted by zymosan was exceeded. A moderate stimulatory action comparable with that of zymosan was found when extracts from Echmaceea, Aleo and Prumis were used, as well as in the case of Propolis. The relationship between stimulatory effect and the concentration range is modulated as function of the extract source, several peaks being observed for some dilutions (Saponana), but generally no quantitative relations were obtained. By studying the time when a chemiluminescence peak was observed, it is possible to estimate wether the weight of the NADPH oxidase or myeloperoxidase pathways are involved in the stimulatory effect on polymorphonuclear leukocytes. PMID:11712436

Crocnan, D O; Greabu, M; Olinescu, R

2000-01-01

378

High-density assembly of chemiluminescence functionalized gold nanodots on multiwalled carbon nanotubes and their application as biosensing platforms  

NASA Astrophysics Data System (ADS)

A one-step strategy was developed for high-density assembly of N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized gold nanodots onto the sidewalls of chitosan-grafted multiwalled carbon nanotubes (cs-MWCNTs) via the reduction of HAuCl4 with ABEI in the presence of cs-MWCNTs, resulting in novel hybrid nanomaterials with excellent chemiluminescence and electrochemiluminescence properties.A one-step strategy was developed for high-density assembly of N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized gold nanodots onto the sidewalls of chitosan-grafted multiwalled carbon nanotubes (cs-MWCNTs) via the reduction of HAuCl4 with ABEI in the presence of cs-MWCNTs, resulting in novel hybrid nanomaterials with excellent chemiluminescence and electrochemiluminescence properties. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr05574d

Zhang, Hongli; Cui, Hua

2014-02-01

379

The study of chemiluminescence in gastric and colonic carcinoma cell lines treated by anti-tumor drugs  

Microsoft Academic Search

AIM: To study the influence of chemotherapy on proliferation activation of tumor cell by observing the change of chemiluminescence (CL) and cell cycle in various tumor cell lines after mitomycin C treated. METHODS: BGC823 and LoVo cell lines were all cultured in RPMI-1640, and then were adjusted to a concentration of 1×105 cells\\/ml in fresh media and incubated for 24

Che Chen; Fu-Kun Liu; Xiao-Ping Qi; Jie-Shou Li

2003-01-01

380

Simple Chemiluminescence Assays for Free Radicals in Venous Blood and Serum Samples: Results in Atopic, Psoriasis, MCS and Cancer Patients  

Microsoft Academic Search

Summary Objective: To investigate the generation of reactive oxygen species (ROS) in serum and venous blood as well as the serum antioxidative activity (AOA) in patients and healthy controls by means of a simplified chemiluminescence (CL) methodology. Study Participants:48 Atopic eczema, 23 psoriasis, 15 multiple chemical sensitivity (MCS) and 35 cancer patients together with 22 healthy volunteers. Methods:ROS generation\\/photon emission

G. Ionescu; M. Merk; R. Bradford

1999-01-01

381

Determination of vitamin K homologues by high-performance liquid chromatography with on-line photoreactor and peroxyoxalate chemiluminescence detection  

Microsoft Academic Search

A sensitive and highly selective high-performance liquid chromatography (HPLC) method was developed for the determination of vitamin K homologues including phylloquinone (PK), menaquinone-4 (MK-4) and menaquinone-7 (MK-7) in human plasma using post-column peroxyoxalate chemiluminescence (PO-CL) detection following on-line ultraviolet (UV) irradiation. The method was based on ultraviolet irradiation (254nm, 15W) of vitamin K to produce hydrogen peroxide and a fluorescent

Sameh Ahmed; Naoya Kishikawa; Kenichiro Nakashima; Naotaka Kuroda

2007-01-01

382

Chemiluminescence behavior of CdTe-hydrogen peroxide enhanced by sodium hypochlorite and sensitized sensing of estrogens  

PubMed Central

It has been found that sodium hypochlorite enhanced the chemiluminescence (CL) of the CdTe nanocrystal (NC)-hydrogen peroxide system and that estrogens inhibited these CL signals in alkaline solution. CL spectra were used to investigate the mechanism of the CL enhancement. On the basis of the inhibition, a flow-injection CL method has been established for determination of three natural estrogens. PMID:24855461

2014-01-01

383

Determination of organic peroxides by liquid chromatography with on-line post-column ultraviolet irradiation and peroxyoxalate chemiluminescence detection  

Microsoft Academic Search

A HPLC method was developed for the simultaneous determination of organic peroxides and hydrogen peroxide with peroxyoxalate chemiluminescence (PO-CL) detection following on-line UV irradiation. Organic peroxides [i.e., benzoyl peroxide (BP), tert.-butyl hydroperoxide (BHP), tert.-butyl perbenzoate (BPB), cumene hydroperoxide (CHP)] were UV irradiated (254 nm, 15 W) to generate hydrogen peroxide, which was determined by PO-CL detection. The conditions for UV

Mitsuhiro Wada; Keiyu Inoue; Ayuko Ihara; Naoya Kishikawa; Kenichiro Nakashima; Naotaka Kuroda

2003-01-01

384

Chemiluminescent Immunoperoxidase Assay for the Dot Blot Hybridization Detection of Parvovirus B19 DNA Using a Low Light Imaging Device  

Microsoft Academic Search

A new synthetized stable trifluoro-substituted acridan (2?, 3?, 6?-trifluorophenyl 10-methylacridan-9-carboxylate known as Lumigen PS-3) has been applied as chemiluminescent substrate of the horseradish peroxidase (HRP) enzyme (neutral isoenzyme C) in a dot blot hybridization assay for the detection of B19 Parvovirus DNA. The dot blot hybridization assay uses digoxigenin-labeled DNA probes which are immunoenzymatically revealed by anti-digoxigenin Fab fragments conjugated

Stefano Girotti; Monica Musiani; Elida Ferri; Giorgio Gallinella; Marialuisa Zerbini; Aldo Roda; Giovanna Gentilomi; Simona Venturoli

1996-01-01

385

Organic Hydroperoxide-Induced Chemiluminescence of Follicular Fluid and Blood Serum Samples Obtained from Women Pretreated for in vitro Fertilization  

Microsoft Academic Search

The organic hydroperoxide-induced chemiluminescence of follicular fluid obtained from in vitro fertilized patients and its differently separated fractions were evaluated. Peroxidative stress causes a different photo-emission in the samples which alludes to some factors playing a role in the maintenance of the pro-oxidant\\/antioxidant balance. Interactions between the protein compounds of the samples and the organic hydroperoxide associate with formation of

A. Török; P. Németh; B. Török; T. Berki; H.-R. Tinneberg; J. Bódis

2004-01-01

386

Delayed fluorescence spectra of intact leaves photoexcited by sunlight measured with a multichannel Fourier-transform chemiluminescence spectrometer  

NASA Astrophysics Data System (ADS)

Delayed fluorescence spectra of intact leaves of Green pak choi (Brassica rapa var. chinensis) were measured with a multichannel Fourier-transform chemiluminescence spectrometer, which we developed recently. The intact samples, photoexcited by sunlight without artificial light sources, showed delayed fluorescence around 740 nm with a lifetime of ˜6 s. The observed spectra were deconvoluted into two Gaussian bands: the delayed fluorescence from photosystem II and photosystem I complexes. Their relative intensities depended on the chlorophyll concentration, but their wavelengths were unchanged.

Akita, Saeka; Yano, Ayako; Ishii, Hiroshi; Satoh, Chikahiro; Akai, Nobuyuki; Nakata, Munetaka

2013-06-01

387

Pulsed technique for observing infrared emissions from ionic gas phase reactions at low reactant ion concentrations  

NASA Astrophysics Data System (ADS)

A technique has been developed to detect infrared emissions from the products of ionic reactions in plasmas. The technique employs dual-phase digital lock-in amplification and cold filtering to permit the detection of the weak infrared chemiluminescence (IRCL) with a solid-state detector. A novel method of cleanly modulating plasma chemiluminescence by the pulsed introduction of reagent gases has been developed and implemented. This new technique has been tested by studying the well-characterized H-atom reactions, H+Cl2?HCl(v=0-4)+Cl and H+NO2?OH(v=0-3)+NO. Rotational and vibrational distributions have been measured for these two reactions and are presented and compared with previous determinations. Additionally, the associative electron detachment reaction, H+Cl-?HCl(v=0-2)+e, has been studied, demonstrating that IRCL can be collected from reactions occurring at a low number density approaching that of the plasma ionization (˜4×1010cm-3). The resolution, and hence, the information content of the collected emissions from this reaction have been greatly improved over previous work, with which our data are compared.

Williams, T. L.; Decker, B. K.; Babcock, L. M.; Adams, N. G.; Harland, P. W.

2000-05-01

388

Comparability of a hand-held nitric oxide analyser with online and offline chemiluminescence-based nitric oxide measurement.  

PubMed

Practicability is crucial for successful implementation of fractional exhaled nitric oxide (FeNO) measurement into asthma management. The study aimed at comparing a conventional chemiluminescence NO analyser (EcoMedics) with a hand-held device (NIOX MINO) and offline FeNO measurement using a commercially available system in an unselected cohort of children aged 6-16 yr. A secondary objective was to confirm FeNO stability over time in 15 samples from adult volunteers obtained using the offline system. Sixty-six children (mean +/- s.d. age 11.8 +/- 3.0 yr) underwent single breath FeNO measurement in triplets with each device. Offline collected FeNO was measured after offline breath collection into a Mylar balloon and subsequent analysis using the chemiluminescence NO analyser. Variability and between-method agreement were assessed, and stability over time within the Mylar balloons was tested by repeated hourly measurements. FeNO levels ranged from 2 to 113 p.p.b. Intra-class correlation was excellent (r = 0.98, p < 0.001 for each pair). Bland-Altman plots and back-transformation of logarithmic mean differences revealed fair agreement between methods. Stability over time was confirmed over 10 h both at room temperature and when stored under cooling conditions. FeNO values obtained using the chemiluminescence NO analyser, the portable NIOX MINO system and the offline collection technique show between-method agreement within clinically acceptable range. PMID:19682277

Schiller, Barbara; Hammer, Juerg; Barben, Juerg; Trachsel, Daniel

2009-11-01

389

A practical alternative to chemiluminescence-based detection of nitrogen dioxide: cavity attenuated phase shift spectroscopy.  

PubMed

We present results obtained from a greatly improved version of a previously reported nitrogen dioxide monitor (Anal Chem. 2005, 77, 724-728) that utilizes cavity attenuated phase shift spectroscopy (CAPS). The sensor, which detects the optical absorption of nitrogen dioxide within a 20 nm bandpass centered at 440 nm, comprises a blue light emitting diode, an enclosed stainless steel measurement cell (26 cm length) incorporating a resonant optical cavity of near-confocal design and a vacuum photodiode detector. An analog heterodyne detection scheme is used to measure the phase shift in the waveform of the modulated light transmitted through the cell induced by the presence of nitrogen dioxide within the cell. The sensor, which operates at atmospheric pressure, fits into a 19 in.-rack-mounted instrumentation box, weighs 10 kg, and utilizes 70 W of electrical power with pump included. The sensor response to nitrogen dioxide (calculated as the cotangent of the phase shift) is demonstrated to be linear (r2 > 0.9999) within +/- 1 ppb over a range of 0-320 ppb (by volume). The device exhibits a detection limit (3sigma precision) of less than 60 parts per trillion (0.060 ppb) with 10 s integration, a value derived from measurements at NO2 concentration levels of both 0 and 20 ppb; the detection limit improves as the integration time is increased to several hundred seconds. The observed baseline drift is less than +/- 0.5 ppb overthe course of a month. An intercomparison of measurements of ambient NO2 concentrations over several days using this sensor with a quantum cascade laser-based infrared absorption spectrometer and a standard chemiluminescence-based NOx analyzer is presented. The data from the CAPS sensor are highly correlated (r2 > 0.99) with the other two instruments. The absolute agreement between the CAPS and each of the two other instruments is within the expected statistical noise associated with the infrared laser-based absorption spectrometer (+/- 0.3 ppb with 10 s sampling) and chemiluminescence analyzer (+/- 0.4 ppb with 60 s averaging). The major limitation concerning accuracy is a direct spectral interference with phototchemically produced 1,2-dicarbonyl species (e.g., glyoxal, methylglyoxal). However, this interference can be readily removed by shifting the detection band to a slightly longer wavelength and ensuring that the lower edge of the detection band is greater than 455 nm. PMID:18767663

Kebabian, Paul L; Wood, Ezra C; Herndon, Scott C; Freedman, Andrew

2008-08-15

390

Trace analysis of pollutants by use of honeybees, immunoassays, and chemiluminescence detection.  

PubMed

Specific and sensitive analysis to reveal and monitor the wide variety of chemical contaminants polluting all environment compartments, feed, and food is urgently required because of the increasing attention devoted to the environment and health protection. Our research group has been involved in monitoring the presence and distribution of agrochemicals by monitoring beehives distributed throughout the area studied. Honeybees have been used both as biosensors, because the pesticides affect their viability, and as "contaminant collectors" for all environmental pollutants. We focused our research on the development of analytical procedures able to reveal and quantify pesticides in different samples but with a special attention to the complex honeybee matrix. Specific extraction and purification procedures have been developed and some are still under optimization. The analytes of interest were determined by gas or liquid chromatographic methods and by compound-specific or group-specific immunoassays in the ELISA format, the analytical performance of which was improved by introducing luminescence detection. The range of chemiluminescent immunoassays developed was extended to include the determination of completely different pollutants, for example explosives, volatile organic compounds (including benzene, toluene, ethylbenzene, xylenes), and components of plastics, for example bisphenol A. An easier and portable format, a lateral flow immunoassay (LFIA) was added to the ELISA format to increase application flexibility in these assays. Aspects of the novelty, the specific characteristics, the analytical performance, and possible future development of the different chromatographic and immunological methods are described and discussed. PMID:23064670

Girotti, S; Ghini, S; Maiolini, E; Bolelli, L; Ferri, E N

2013-01-01

391

Safety-sparkler wand w/chemiluminescent or electric-light illumination  

US Patent & Trademark Office Database

A juvenile's fantasy-wand so devised as to convey the visual illusion of a sparkedly burning Jul-4th device or fairy-tale magic-wand appearance, by virtue of employing myraid flexible fiberoptic-strands stemming outward from the upper-end of a rigid baton like holding member; whereby two seperate illuminating options are set forth; 1. a minimal weight version employing a substantially conventional expendable chemiluminescent light-cartridge unit set co-axially into the wand body so as to propagate its light outward via an annular light-receptor serving to pipe the light up and outward through the fountain like cluster of billowing fiber-optic strands; 2. an expendable drycell-battery version preferably employing an ultra-bright LED-lamp set co-axially with a cylinderical light-housing so as to efficiently focus light directly into the upper-end abaxially gathered fiber-optic strands, which likewise blossom outward as a billowing array of tiny sparkling tips; --either version including an optional retractably protective-sheath member of tubular shape allowing the user to deploy the fiber-optic strands at will, plus a co-acting off/on switch arrangement in the electric version; both versions thus providing a fantastic visual night-time splendor of shimmering elements in a hand-portable modality which give-off a realistic illusion of an exciting however comparatively dangerous conventional burning sparkler device.

1990-05-08

392

Chemiluminescence and fluorescence spectrum methods for determination of Aflatoxin B1 mediated by FCLA + BSA  

NASA Astrophysics Data System (ADS)

BSA (Bovine Serum Albumin) can enlarge the CL intensity of FCLA(3,7-dihydro-6-{4-{2-(N'-(5-fluoresceinyl) thioureido)ethoxy}phenyl}-2-methylimi-dazo{1,2-a}pyrazin-3-one dosium salt) to 763%. This report presents novel methods for determination of Aflatoxin B1 (AfB1) mediated by FCLA+BSA. The concentration of AFB1 showed an obvious positive correlation with the chemiluminescence (CL) intensity mediated by FCLA+BSA, correlative coefficient R@0.94. This method could measure accurately ng/ml of AfB1 concentration. 365nm as excitated wavelength, 440nm and 520nm-two fluorescence peaks of FCLA+BSA+AfB1 were found. The fluorescence intensity of peak at 440nm showed an obvious positive correlation with the concentration of AFB1, R@0.97; the fluorescence intensity of peak at 520nm showed a positive correlation with the concentration of AFB1, R@0.90. Comparing the peak of FCLA, FCLA+BSA and FCLA+BSA+AfB1 had a 6nm Einstein shift (red shift). The study suggested that CL and fluorescence spectrum methods mediated by FCLA+BSA might be applicable to the determination of AfB1 concentration.

Chen, WenLi; Xing, Da

2005-04-01

393

Carbon nitride quantum dots: a novel chemiluminescence system for selective detection of free chlorine in water.  

PubMed

A facile one-step microwave-assisted approach for the preparation of strong fluorescent carbon nitride quantum dots (g-CNQDs) by using guanidine hydrochloride and EDTA as the precursors was developed. Strong chemiluminescence (CL) emission was observed when NaClO was injected into the prepared g-CNQDs, and a novel CL system for direct detection of free chlorine was established. Free residual chlorine in water was sensitively detected with a detection limit of 0.01 ?M and had a very wide detection range of 0.02 to 10 ?M. On the basis of CL spectral, UV-visible absorption spectral, and electron spin resonance (ESR) spectral studies, as well as investigations on the effects of various free radical scavengers, a possible CL mechanism was proposed. It was suggested that the radiative recombination of oxidant-injected holes and electrons in the g-CNQDs accounted for the CL emission. Meanwhile, (1)O2 on the surface of g-CNQDs, generated from some reactive oxygen species in the g-CNQDs-NaClO system, could transfer energy to g-CNQDs and thus further enhance the CL emission. The CL system is highly sensitive and differentiable, opening a new field for the development of novel CL-emitting species, but also expanding the conventional optical utilizations of g-CNQDs. PMID:24655009

Tang, Yurong; Su, Yingying; Yang, Na; Zhang, Lichun; Lv, Yi

2014-05-01

394

Chemiluminescence of neutrophiles stimulated by opsonized Zymosan in children with bronchial asthma and pneumonia  

NASA Astrophysics Data System (ADS)

Oxygen metabolism of neutrophils after stimulation with opsonized zymosan was examined using chemiluminescence test (in the presence of the patient serum or pooled serum). Into the study 37 children aged from 2 to 12 years were enrolled (20 girls and 17 boys). 10 healthy volunteers comprised the control group (group III). Two groups of patients were established: group I -- children with bronchial asthma (without infection), group II -- children with pneumonia. The examination in both groups was performed twice -- in acute phase and in remission period. The group I in acute phase comprised 16 children and in remission phase 9 children, group II - 21 children in acute phase and 9 children in remission phase, respectively. The following parameters of CL were estimated average value of so called spontaneous CL, maximal excitation of neutrophils after stimulation by zymogen (CLmax), time of zymosan opsonization. The following results were obtained: increased spontaneous CL and CLmax (at the presence of both sera) in acute phase of bronchial asthma and pneumonia in comparison to the control group. In the period of remission both these parameters were insignificantly decreased. The longest time of zymosan opsonization in acute period of disease was observed in children with pneumonia (18 min.). This time did not change during remission phase. Only slightly longer time of opsonization was observed in the patients from group I (in exacerbation) (15 min) than in the control group (13,1 min). This time was prolonged in the clinical remission (20 min).

Lewandowicz-Uszynska, A.; Jankowski, A.

2004-08-01

395

An ultrasensitive streptavidin-functionalized carbon nanotubes platform for chemiluminescent immunoassay.  

PubMed

An ultrasensitive chemiluminescent (CL) immunoassay system was developed for the detection of tumor marker. This sandwich CL assay method was for the first time designed based on a highly efficient streptavidin-functionalized multi-walled carbon nanotubes (MWCNTs) platform. The glass slide was firstly silylanized with 3-gycidoxypropyltrimethoxysilane (GPTMS) to generate surface epoxy group functionality. Subsequently, the MWCNTs/chitosan solution was mixed with streptavidin solution, and a certain amount of the resulting suspension was dropped on the surface of the epoxy-activated glass substrate to form a firm streptavidin-functionalized MWCNTs platform. The biofunctionalized-MWCNTs platform shows large reactive surface area and excellent biocompatibility. The capture antibody can be efficiently immobilized on the biosensing platform surface based on the highly selective recognition of streptavidin to biotinylated antibody. Using ?-fetoprotein (AFP) as model analyte, the proposed method exhibits wide linear range of 0.001-0.1 ng mL(-1) with a low detection limit down to 0.52 pg mL(-1). The CL immunoassay system displays 7.9-fold increase in the detection sensitivity compared to the immunosensor without using MWCNTs. Moreover, the resulting immunosensor demonstrates excellent specificity, good reproducibility, and acceptable stability. This streptavidin-functionalized MWCNTs platform opens a novel and promising avenue for fabricating ultrasensitive CL immunoassay system. PMID:23567121

Yang, Zhanjun; Shen, Juan; Li, Juan; Zhu, Jing; Hu, Xiaoya

2013-04-24

396

Oxidation of small boron agglomerates: formation of and chemiluminescent emission from BBO  

SciTech Connect

A source configuration that lies intermediate to a low-pressure effusing molecular beam and a high-pressure flow device is used to generate boron cluster molecules in a highly oxidizing environment. Using this source operating in an NO/sub 2/ oxidative environment, the authors generate a chemiluminescent emission spectrum, which they attribute to the asymmetric BBO molecule. The observed spectrum is characterized by a strong ..delta nu.. = ..delta nu.. = 40 cm/sup /minus/1/ sequence grouping and a weaker ..delta nu.. = + 1 sequence (..delta nu.. = 40 cm/sup /minus/1/), 440 cm/sup /minus/1/ to higher energy. A second sequence with ..delta nu.. /approximately/ 142 cm/sup /minus/1/ is also observed. Combining the 440-cm/sup /minus/1/ upper-state frequency with the 142-cm/sup /minus/1/ sequence structure implies a lower-state frequency of /approximately/ 582 cm/sup /minus/1/ for the B-B stretch, consistent with ab initio calculation.

Devore, T.C.; Woodward, J.R.; Gole, J.L.

1988-12-01

397

Highly sensitive multianalyte immunochromatographic test strip for rapid chemiluminescent detection of ractopamine and salbutamol.  

PubMed

A novel immunochromatographic assay (ICA) was proposed for rapid and multiple assay of ?2-agonists, by utilizing ractopamine (RAC) and salbutamol (SAL) as the models. Owing to the introduction of chemiluminescent (CL) approach, the proposed protocol shows much higher sensitivity. In this work, the described ICA was based on a competitive format, and horseradish peroxidase-tagged antibodies were used as highly sensitive CL probes. Quantitative analysis of ?2-agonists was achieved by recording the CL signals of the probes captured on the two test zones of the nitrocellulose membrane. Under the optimum conditions, RAC and SAL could be detected within the linear ranges of 0.50-40 and 0.10-50 ng mL(-1), with the detection limits of 0.20 and 0.040 ng mL(-1) (S/N=3), respectively. The whole process for multianalyte immunoassay of RAC and SAL can be completed within 20 min. Furthermore, the test strip was validated with spiked swine urine samples and the results showed that this method was reliable in measuring ?2-agonists in swine urine. This CL-based multianalyte test strip shows a series of advantages such as high sensitivity, ideal selectivity, simple manipulation, high assay efficiency and low cost. Thus, it opens up new pathway for rapid screening and field analysis, and shows a promising prospect in food safety. PMID:25066723

Gao, Hongfei; Han, Jing; Yang, Shijia; Wang, Zhenxing; Wang, Lin; Fu, Zhifeng

2014-08-11

398

Hyperspectral infrared imaging of HF(v, J) chemiluminescence and gain in chemically reacting flowfields.  

PubMed

This paper presents results from investigations of chemically reacting flowfields and optical gain profiles in HF chemical laser media by infrared hyperspectral imaging. Subsonic and supersonic chemiluminescent F+H2 reacting flowfields, produced in high-fluence microwave-driven reactors, were imaged at a series of wavelengths, 2.6-3.1 microm, by a low-order, spectrally scanning Fabry-Perot interferometer mated to an infrared camera. The resulting hyperspectral data cubes define the spectral and spatial distributions of the emission. Spectrally resolved images at high spatial resolution were processed to determine spatial distributions of the excited-state concentrations of the product HF(v, J) molecules, as well as spatial distributions of small-signal gain on specific laser transitions. Additional high-resolution Fourier transform spectroscopy and spectral fitting analysis determined detailed excited-state distributions in the reacting flowfields. The measurements showed that energetic HF(v, J) state distributions were generated by both the supersonic and fast-flow subsonic mixing schemes. In particular, the subsonic reactor produced a spatially distributed field of inverted, near-nascent state populations, with small-signal gains near 2-3%/cm. PMID:17518458

Rawlins, W T; Oakes, D B; Davis, S J

2007-07-26

399

Chemiluminescent microparticle immunoassay based detection and prevalence of HCV infection in district Peshawar Pakistan  

PubMed Central

Background Due to the high rate of asymptomatic infections an advanced screening assay is of prompt importance to be used for the clinical diagnosis of HCV. Early detection of anti HCV is the first step in the management of chronic hepatitis and in the selection of patients needing treatments. In the current study we have first time used the advanced serological diagnostic technique i.e. Chemiluminescent Microparticle Immuno Assay (CMIA) for the detection of HCV infection in Peshawar Pakistan. Methods A total number of 982 samples were collected among the general public belongs to the different areas of district Peshawar. The samples were centrifuged at high speed to obtain a clear supernatant serum. All the samples were run on Architect system a fully automated immuno analyzer CMIA base technology. Results Out of 982 blood samples analyzed in this study, 160 (15.9%) were confirmed to be positive for active HCV infection. The overall prevalence was found to be 13.4%. Gender wise prevalence was recorded to be higher in male (19.1%) than female (12.7%). The age group 21-30 years was identified as the highest risk group among the studied population. Conclusion Among the tested samples, overall prevalence of active HCV infection was found to be 13.4% in the general population of Peshawar Pakistan. The young middle aged population of this region was at higher risk of HCV ailments compared to the other age groups. PMID:25016473

2014-01-01

400

Determination of folates by HPLC-chemiluminescence using a ruthenium(II)-cerium(IV) system, and its application to pharmaceutical preparations and supplements.  

PubMed

A chemiluminescence (CL) reaction of folic acid (FA) with ruthenium (II) and cerium (IV) was applied to quantify FA-related compounds such as FA, dihydrofolic acid, tetrahydrofolic acid, 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolic acid and methotrexate (MTX). Among the FAs, 5-methyltetrahydrofolic acid provided the highest CL intensity. HPLC-CL detection of FA was applied to quantify FA in pharmaceutical preparations and supplements. Analytical samples were separated on a semi-micro ODS column with a mixture of 20?mM phosphate buffer (pH?5.7) and acetonitrile (94 : 6, v/v %). The separated samples were mixed with a post-column CL reagent consisting of 1.5?mM Ru(bipy)3 (2+) and 1.0?mM Ce(SO4 )2 , then the generated CL was monitored. The calibration range for FA was 10-100??M and the limit of detection was 1.34??M (signal-to-noise ratio of 3). Repeatabilities were 4.2, 4.6 and 5.0 RSD% (10, 25, 50??M), and the recoveries for FA supplement, vitamin B complex supplement and FA-containing medication (tablet) were 102.4?±?10.5, 103.3?±?13.3 and 100.3?±?8.5%, respectively. The described method is robust against changes in the chromatographic parameters of?±?3.3 or?±?1.5%. The measured FA content corresponded well to the labeled content of FA-containing products (100.6-104.9%), demonstrating the precision and accuracy of this method for the evaluation of FA pharmaceutical preparations. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24403177

Ikeda, Rie; Ichiyama, Kosuke; Tabuchi, Naoto; Wada, Mitsuhiro; Kuroda, Naotaka; Nakashima, Kenichiro

2014-11-01

401

Enzyme Reactions  

NSDL National Science Digital Library

This video shows an enzyme reaction lab. The teacher demonstrates how the enzyme, catalase, reacts with hydrogen peroxide (a substrate found in cells). The teacher first demonstrates a normal enzyme reaction. He or she then goes on to show how manipulating temperature and pH will affect the reaction of an enzyme.

School, Minerva D.

2011-10-03

402

Reversible Reactions  

NSDL National Science Digital Library

Watch a reaction proceed over time. How does total energy affect a reaction rate? Vary temperature, barrier height, and potential energies. Record concentrations and time in order to extract rate coefficients. Do temperature dependent studies to extract Arrhenius parameters. This simulation is best used with teacher guidance because it presents an analogy of chemical reactions.

Simulations, Phet I.; Barbera, Jack; Koch, Linda; Lemaster, Ron; Adams, Wendy

2005-09-01

403

Nuclear Reactions  

Microsoft Academic Search

Nuclear reactions generate energy in nuclear reactors, in stars, and are responsible for the existence of all elements heavier than hydrogen in the universe. Nuclear reactions denote reactions between nuclei, and between nuclei and other fundamental particles, such as electrons and photons. A short description of the conservation laws and the definition of basic physical quantities is presented, followed by

C. A. Bertulani

2009-01-01

404

Chemical Reactions  

NSDL National Science Digital Library

We don't often stop to think about it, but underlying many of our everyday activities are chemical reactions. From the cooking of an egg to the growth of a child, chemical reactions make things happen. Although many of the reactions that support our lives

National Science Teachers Association (NSTA)

2009-05-01

405

Special Reactions  

NSDL National Science Digital Library

The basics of chemical reactions were covered in the first chemistry book, including how to write and balance chemical equations that represent those reactions. There is also a quick review of chemical reactions in Chapter 1 of this book. We're going to d

Robertson, William C.

2010-03-01

406

Development and validation of a sensitive and fast chemiluminescent enzyme immunoassay for the detection of genetically modified maize.  

PubMed

Proteins from the Cry 1 family, in particular Cry 1Ab, are commonly expressed in genetically modified Bt maize in order to control chewing insect pests. A sensitive chemiluminescent sandwich enzyme immunoassay for the detection of Cry1Ab protein from genetically modified Bt maize has been developed and validated. A Cry1Ab protein-specific antibody was immobilized on 96- or 384-well microtiter plates in order to capture the Cry1Ab toxin in the sample; the bound toxin was then detected by employing a second anti-Cry1Ab antibody and a horseradish peroxidase-labeled anti-antibody, followed by measurement of the enzyme activity with an enhanced chemiluminescent system. The chemiluminescent assay fulfilled all the requirements of accuracy and precision and exhibited limits of detection of a few pg mL(-1) Cry1Ab (3 or 5 pg mL(-1), depending on the assay format), which are significantly lower than that achievable using conventional colorimetric detection of peroxidase activity and also represent an improvement compared to previously developed Cry1Ab immunoassays. High-throughput analysis can be performed using the 384-well microtiter plate format immunoassay, which also allows one to reduce the consumption of samples and reagents. Validation of the assay, performed by analyzing certified reference materials, proved that the immunoassay is able to detect the presence of the Cry1Ab protein in certified reference samples containing as low as 0.1% of MON 810 genetically modified Bt maize. This value is below the threshold requiring mandatory labeling of foods containing genetically modified material according to the actual EU regulation. PMID:16491341

Roda, A; Mirasoli, M; Guardigli, M; Michelini, E; Simoni, P; Magliulo, M

2006-03-01

407

Chemiluminescence detection with water-soluble iridium(iii) complexes containing a sulfonate-functionalised ancillary ligand.  

PubMed

The chemiluminescence from four cyclometalated iridium(iii) complexes containing an ancillary bathophenanthroline-disulfonate ligand exhibited a wide range of emission colours (green to red), and in some cases intensities that are far greater than the commonly employed benchmark reagent, [Ru(bpy)3](2+). A similar complex incorporating a sulfonated triazolylpyridine-based ligand enabled the emission to be shifted into the blue region of the spectrum, but the responses with this complex were relatively poor. DFT calculations of electronic structure and emission spectra support the experimental findings. PMID:25271898

Truong, Josephine; Spilstead, Kara B; Barbante, Gregory J; Doeven, Egan H; Wilson, David J D; Barnett, Neil W; Henderson, Luke C; Altimari, Jarrad M; Hockey, Samantha C; Zhou, Ming; Francis, Paul S

2014-10-15

408

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presented are three demonstrations for chemical education. The activities include: (1) demonstration of vapor pressure; (2) a multicolored luminol-based chemiluminescence demonstration; and (3) a Charles's Law/Vapor pressure apparatus. (RH)

Gilbert, George L., Ed.

1987-01-01

409

Spectroscopic studies on the lanthanide sensitized luminescence and chemiluminescence properties of fluoroquinolone with different structure  

NASA Astrophysics Data System (ADS)

Lanthanide sensitized luminescence and chemiluminescence (CL) are of great importance because of the unique spectral properties, such as long lifetime, large Stokes shifts, and narrow emission bands characteristic to lanthanide ions (Ln 3+). With the fluoroquinolone (FQ) compounds including enoxacin (ENX), norfloxacin (NFLX), lomefloxacin (LMFX), fleroxacin (FLRX), ofloxacin (OFLX), rufloxacin (RFX), gatifloxacin (GFLX) and sparfloxacin (SPFX), the luminescence and CL properties of Tb 3+-FQ and Eu 3+-FQ complexes have been investigated in this contribution. Ce 4+-SO 32- in acidic conditions was taken as the CL system and sensitized CL intensities of Tb 3+-FQ and Eu 3+-FQ complexes were determined by flow-injection analysis. The luminescence and CL spectra of Tb 3+-FQ complexes show characteristic peaks of Tb 3+ at 490 nm, 545 nm, 585 nm and 620 nm. Complexes of Tb 3+-ENX, Tb 3+-NFLX, Tb 3+-LMFX and Tb 3+-FLRX display relatively strong emission intensity compared with Tb 3+-OFLX, Tb 3+-RFX, Tb 3+-GFLX and Tb 3+-SPFX. Quite weak peaks with unique characters of Eu 3+ at 590 nm and 617 nm appear in the luminescence and CL spectra of Eu 3+-ENX, but no notable sensitized luminescence and CL of Eu 3+ could be observed when Eu 3+ is added into other FQ. The distinct differences on emission intensity of Tb 3+-FQ and Eu 3+-FQ might originate from the different energy gap between the triplet levels of FQ and the excited levels of the Ln 3+. The different sensitized luminescence and CL signals among Tb 3+-FQ complexes could be attributed to different optical properties and substituents of these FQ compounds. The detailed mechanism involved in the luminescence and CL properties of Tb 3+-FQ and Eu 3+-FQ complexes has been investigated by analyzing the luminescence and CL spectra, quantum yields, and theoretical calculation results.

Sun, Chunyan; Ping, Hong; Zhang, Minwei; Li, Hongkun; Guan, Fengrui

2011-11-01

410

Spectroscopic studies on the lanthanide sensitized luminescence and chemiluminescence properties of fluoroquinolone with different structure.  

PubMed

Lanthanide sensitized luminescence and chemiluminescence (CL) are of great importance because of the unique spectral properties, such as long lifetime, large Stokes shifts, and narrow emission bands characteristic to lanthanide ions (Ln(3+)). With the fluoroquinolone (FQ) compounds including enoxacin (ENX), norfloxacin (NFLX), lomefloxacin (LMFX), fleroxacin (FLRX), ofloxacin (OFLX), rufloxacin (RFX), gatifloxacin (GFLX) and sparfloxacin (SPFX), the luminescence and CL properties of Tb(3+)-FQ and Eu(3+)-FQ complexes have been investigated in this contribution. Ce(4+)-SO(3)(2-) in acidic conditions was taken as the CL system and sensitized CL intensities of Tb(3+)-FQ and Eu(3+)-FQ complexes were determined by flow-injection analysis. The luminescence and CL spectra of Tb(3+)-FQ complexes show characteristic peaks of Tb(3+) at 490 nm, 545 nm, 585 nm and 620 nm. Complexes of Tb(3+)-ENX, Tb(3+)-NFLX, Tb(3+)-LMFX and Tb(3+)-FLRX display relatively strong emission intensity compared with Tb(3+)-OFLX, Tb(3+)-RFX, Tb(3+)-GFLX and Tb(3+)-SPFX. Quite weak peaks with unique characters of Eu(3+) at 590 nm and 617 nm appear in the luminescence and CL spectra of Eu(3+)-ENX, but no notable sensitized luminescence and CL of Eu(3+) could be observed when Eu(3+) is added into other FQ. The distinct differences on emission intensity of Tb(3+)-FQ and Eu(3+)-FQ might originate from the different energy gap between the triplet levels of FQ and the excited levels of the Ln(3+). The different sensitized luminescence and CL signals among Tb(3+)-FQ complexes could be attributed to different optical properties and substituents of these FQ compounds. The detailed mechanism involved in the luminescence and CL properties of Tb(3+)-FQ and Eu(3+)-FQ complexes has been investigated by analyzing the luminescence and CL spectra, quantum yields, and theoretical calculation results. PMID:21821467

Sun, Chunyan; Ping, Hong; Zhang, Minwei; Li, Hongkun; Guan, Fengrui

2011-11-01

411

Screening for immunomodulators: Effects of xenobiotics on macrophage chemiluminescence in vitro  

SciTech Connect

Macrophage chemiluminescence (CL) was evaluated as a primary screening assay by assessing the modulatory activity of 17 different chemicals. The chemicals were either known immunomodulatory drugs or environmental toxicants with reported immunomodulatory activity. Elicited mouse peritoneal macrophages were exposed to the chemicals in vitro, and CL was measured in response to an opsonized yeast stimulus. Ten chemicals (hydrocortisone, dextran sulfate, di-n-octyltin dichloride, dimethyltin dichloride, azathioprine, lambda carrageenan (l-carrageenan), lead, N-propyl gallate, gallic acid, and indomethacin) were identified as effective modulators of CL. The polyanions dextran sulfate and l-carrageenan either suppressed or enhanced CL, depending on the experimental conditions, while the remaining modulators were inhibitory. A series of secondary assays was used to verify this modulatory activity and to explore different mechanisms of action. Each effective modulator altered only a few specific components of the more complex CL response, and the following general mechanisms were apparent. At least 2 chemicals showed distinct antioxidant activity and thus probably did not alter functional aspects of macrophage CL. Chemicals which blocked Fc receptor function delayed the peak CL of macrophages stimulated by opsonized yeast. Nine of the 10 modulators inhibited hydrogen peroxide release, but only 3 inhibited the release of superoxide. Finally, some effective modulators were chemicals known to interact with cell membranes or specific membrane receptors, and these were able to directly induce a CL response without the addition of opsonized yeast as a stimulus. Thus, macrophage CL was a simple, quantitative, yet sensitive immunotoxicologic screening assay capable of identifying many known immunomodulatory drugs.

Tam, P.E.; Hinsdill, R.D. (Univ. of Wisconsin, Madison (USA))

1990-04-01

412

Synthesis, Electrochemistry and Electrogenerated Chemiluminesce of two BODIPY-Appended Bipyridine Homologues  

PubMed Central

Two new 2,2’-bipyridine (bpy) derivatives containing ancillary BODIPY chromophores attached at the 5- and 5’-positions (BB3) or 6- and 6’-positions (BB4) were prepared and characterized. In this work, the basic photophysics, electrochemistry and electrogenerated chemiluminescence (ECL) of BB3 and BB4 are compared with those previously reported for a related bpy-BODIPY derivative (BB2) (J. Phys. Chem. C 2011, 115, 17993–18001). Cyclic voltammetry revealed that BB3 and BB4 display reversible 2e? oxidation and reduction waves, which consist of two closely spaced (50 – 70 mV) 1e? events. This redox behavior is consistent with the frontier molecular orbitals calculated for BB3 and BB4 and indicates that the 2,2’-bipyridine spacer of each bpy- BODIPY homologue does not facilitate efficient electronic communication between the tethered indacene units. In the presence of a coreactant such as tri-n-propylamine (TPA) or benzoyl peroxide (BPO), BB3 and BB4 exhibit strong ECL and produce spectra that are very similar to their corresponding photoluminescence profiles. The ECL signal obtained under annihilation conditions, however, is significantly different and is characterized by two distinct bands. One of these bands is centered at ~570 nm and is attributed to emission via an S- or T-route. The second band, occurs at longer wavelengths and is centered around ~740 nm. The shape and concentration dependence of this long-wavelength ECL signal is not indicative of emission from an excimer or aggregate, but rather is suggests that a new emissive species is formed from the bpy-BODIPY luminophores during the annihilation process. PMID:23980850

Qi, Honglan; Teesdale, Justin J.; Pupillo, Rachel C.

2014-01-01

413

Interference from digitoxin-like immunoreactive factors reduced in a new monoclonal chemiluminescent digitoxin assay.  

PubMed

Endogenous digoxin-like immunoreactive factors (DLIF) can interfere with some digoxin immunoassays. We looked for similar interference, called digitoxin-like immunoreactive factors (DTLIF) in two digitoxin immunoassays: A new chemiluminescent assay (CLIA), processed on the automated random access immunoassay system ACS:180, and a fluorescent polarization assay (FPIA), processed on the semiautomated TDx batch analyzer. One hundred thirty-seven samples of sera were tested from nondigitalized pregnant women, patients with liver or kidney diseases, and cord blood. The CLIA digitoxin assay uses a murine monoclonal antibody and requires no sample pretreatment; the FPIA digitoxin assay uses a polyclonal rabbit antibody and requires sample precipitation. Both assays have a similar dynamic range and sensitivity and give comparable results with commercial controls and external quality control survey samples. Although the CLIA detected no digitoxin in any sample tested, the FPIA showed apparent digitoxin concentrations of more than 2.0 ng/ml for 100% and 44% among cord blood and liver disease specimens, respectively. The highest DTLIF concentration was found in serum from a patient with liver disease (18.1 ng/ml). When spiked with 32 ng/ml digitoxin, six of the samples containing DTLIF generated FPIA digitoxin values of 6% to 27.5% more than the expected digitoxin levels. Two specimens with no detectable DTLIF activity were run as controls, and when spiked with digitoxin, showed target digitoxin concentrations in the FPIA. The CLIA recovered near the target digitoxin values (32 ng/ml) in all spiked samples. It was concluded that the polyclonal FPIA digitoxin assay may give discordant digitoxin concentrations in some patient groups because of interference from digitoxin-like immunoreactive factors. The CLIA digitoxin assay is not affected by DTLIF interference. PMID:9853984

Datta, P; Dasgupta, A

1998-12-01

414

Synthesis, electrochemistry, and electrogenerated chemiluminescence of two BODIPY-appended bipyridine homologues.  

PubMed

Two new 2,2'-bipyridine (bpy) derivatives containing ancillary BODIPY chromophores attached at the 5- and 5'-positions (BB3) or 6- and 6'-positions (BB4) were prepared and characterized. In this work, the basic photophysics, electrochemistry, and electrogenerated chemiluminescence (ECL) of BB3 and BB4 are compared with those previously reported for a related bpy-BODIPY derivative (BB2) (J. Phys. Chem. C 2011, 115, 17993-18001). Cyclic voltammetry revealed that BB3 and BB4 display reversible 2e(-) oxidation and reduction waves, which consist of two closely spaced (50-70 mV) 1e(-) events. This redox behavior is consistent with the frontier molecular orbitals calculated for BB3 and BB4 and indicates that the 2,2'-bipyridine spacer of each bpy-BODIPY homologue does not facilitate efficient electronic communication between the tethered indacene units. In the presence of a coreactant such as tri-n-propylamine (TPA) or benzoyl peroxide (BPO), BB3 and BB4 exhibit strong ECL and produce spectra that are very similar to their corresponding photoluminescence profiles. The ECL signal obtained under annihilation conditions, however, is significantly different and is characterized by two distinct bands. One of these bands is centered at ?570 nm and is attributed to emission via an S- or T-route. The second band occurs at longer wavelengths and is centered around ?740 nm. The shape and concentration dependence of this long-wavelength ECL signal is not indicative of emission from an excimer or aggregate, but rather it suggests that a new emissive species is formed from the bpy-BODIPY luminophores during the annihilation process. PMID:23980850

Qi, Honglan; Teesdale, Justin J; Pupillo, Rachel C; Rosenthal, Joel; Bard, Allen J

2013-09-11

415

Chemiluminescence Imaging for a Protein Assay via Proximity-Dependent DNAzyme Formation.  

PubMed

An array-based chemiluminescence (CL) imaging method is presented for simple and high throughput detection of protein targets via the formation of a proximity-dependent DNAzyme to produce sensitive CL signal. The protein array is prepared by covalently immobilizing single-stranded guanine-rich nucleic acid 1-labeled antibody 1 (GDNA1-Ab1) or GDNA-thrombin aptamer subunit 1 (Apt-P1) as the capture probe on each sensing site on an aldehyde-functionalized disposable glass chip. In the presence of target protein, hemin, and another GDNA2-Ab2 or Apt-P2 probe, a sandwich complex among the protein and two probes can be formed to trigger the proximity assembly of GDNA1, hemin, and GDNA2, which leads to the formation of hemin-G-quadruplex DNAzyme. At different sensing sites, the DNAzyme-induced CL signals are simultaneously collected by a charge-coupled device for imaging readout of the sensing events. As a proof of concept, the proposed array-based CL imaging strategy is applied to detect carcinoembryonic antigen and thrombin and shows wide linear ranges over 4 and 5 orders of magnitude with the detection limits of 0.15 ng mL(-1) and 0.49 pM, respectively. Benefiting from the one-step proximity-dependent DNAzyme formation, the assay method is extremely simple and can be carried out within 40 min. By using different probes, the array can be easily used to detect more protein analytes. The advantages of easy operation, short assay time, good sensitivity, and versatility make it a promising candidate for point-of-care testing and commercial application. PMID:25181362

Zong, Chen; Wu, Jie; Liu, Mengmeng; Yang, Linlin; Yan, Feng; Ju, Huangxian

2014-10-01

416

A gas-phase chemiluminescence-based analyzer for waterborne arsenic  

USGS Publications Warehouse

We show a practical sequential injection/zone fluidics-based analyzer that measures waterborne arsenic. The approach is capable of differentiating between inorganic As(III) and As(V). The principle is based on generating AsH 3 from the sample in a confined chamber by borohydride reduction at controlled pH, sparging the chamber to drive the AsH3 to a small reflective cell located atop a photomultiplier tube, allowing it to react with ozone generated from ambient air, and measuring the intense chemiluminescence that results. Arsine generation and removal from solution results in isolation from the sample matrix, avoiding the pitfalls encountered in some solution-based analysis techniques. The differential determination of As(III) and As(V) is based on the different pH dependence of the reducibility of these species to AsH3. At pH ???1, both As(III) and As(V) are quantitatively converted to arsine in the presence of NaBH4. At a pH of 4-5, only As(III) is converted to arsine. In the present form, the limit of detection (S/N = 3) is 0.05 ??g/L As at pH ???1 and 0.09 ??g/L As(III) at pH ???4-5 for a 3-mL sample. The analyzer is intrinsically automated and requires 4 min per determination. It is also possible to determine As(III) first at pH 4.5 and then determine the remaining As in a sequential manner; this requires 6 min. There are no significant practical interferences. A new borohydride solution formulation permits month-long reagent stability. ?? 2006 American Chemical Society.

Idowu, A.D.; Dasgupta, P.K.; Genfa, Z.; Toda, K.; Garbarino, J.R.

2006-01-01

417

Rapid, quantitative determination of bacteria in water. [adenosine triphosphate  

NASA Technical Reports Server (NTRS)

A bioluminescent assay for ATP in water borne bacteria is made by adding nitric acid to a water sample with concentrated bacteria to rupture the bacterial cells. The sample is diluted with sterile, deionized water, then mixed with a luciferase-luciferin mixture and the resulting light output of the bioluminescent reaction is measured and correlated with bacteria present. A standard and a blank also are presented so that the light output can be correlated to bacteria in the sample and system noise can be substracted from the readings. A chemiluminescent assay for iron porphyrins in water borne bacteria is made by adding luminol reagent to a water sample with concentrated bacteria and measuring the resulting light output of the chemiluminescent reaction.

Chappelle, E. W.; Picciolo, G. L.; Thomas, R. R.; Jeffers, E. L.; Deming, J. W. (inventors)

1978-01-01

418

Nuclear Reactions  

Microsoft Academic Search

Nuclear reactions generate energy in nuclear reactors, in stars, and are\\u000aresponsible for the existence of all elements heavier than hydrogen in the\\u000auniverse. Nuclear reactions denote reactions between nuclei, and between nuclei\\u000aand other fundamental particles, such as electrons and photons. A short\\u000adescription of the conservation laws and the definition of basic physical\\u000aquantities is presented, followed by

C. A. Bertulani; B. Kinematics

2009-01-01

419

Determination of antimony in environment samples by gas phase chemiluminescence detection following flow injection hydride generation and cryotrapping.  

PubMed

A novel method for the determination of antimony in environmental samples was developed with gas phase chemiluminescence detection following flow injection hydride generation and cryotrapping. The stibine, generated from samples by borohydride reduction of antimony using flow injection technique, was separated by using a new gas-liquid separator, dried with an ice-salt cryogenic bath and concentrated in a glass U-tube immersed in liquid nitrogen. Re-vaporization of stibine based on its boiling point was achieved by allowing the tube to warm at room temperature. A gas phase chemiluminescence signal was produced during the ozonation of the hydride in a reflective chamber. Under optimal conditions, the proposed method was characterized by a wide linear calibration range from 1.0microgL(-1) to 10.0mgL(-1) with a detection limit of 0.18microgL(-1) (n=11). The relative standard deviation for 10.0microgL(-1) antimony was 3.56% (n=11) and the sampling rate was 15 samples h(-1). Blank signal was reduced by the purification of reagents and the interference from transition metal ions was eliminated