Carbonaceous adsorbents derived from textile cotton waste for the removal of Alizarin S dye from aqueous effluent: kinetic and equilibrium studies.

PubMed

Wanassi, Béchir; Hariz, Ichrak Ben; Ghimbeu, Camélia Matei; Vaulot, Cyril; Hassen, Mohamed Ben; Jeguirim, Mejdi

2017-04-01

Recycling cotton waste derived from the textile industry was used as a low-cost precursor for the elaboration of an activated carbon (AC) through carbonization and zinc chloride chemical activation. The AC morphological, textural, and surface chemistry properties were determined using different analytical techniques including Fourier transform infrared, temperature programmed desorption-mass spectroscopy, nitrogen manometry and scanning electron microscopy. The results show that the AC was with a hollow fiber structure in an apparent diameter of about 6.5 μm. These analyses indicate that the AC is microporous and present a uniform pore size distributed centered around 1 nm. The surface area and micropore volume were 292 m 2 .g -1 and 0.11 cm 3 .g -1 , respectively. Several types of acidic and basic oxygenated surface groups were highlighted. The point of zero charge (pH PZC ) of theca was 6.8. The AC performance was evaluated for the removal of Alizarin Red S (ARS) from aqueous solution. The maximum adsorption capacity was 74 mg.g -1 obtained at 25 °C and pH = 3. Kinetics and equilibrium models were used to determine the interaction nature of the ARS with the AC. Statistical tools were used to select the suitable models. The pseudo-second order was found to be the most appropriate kinetic model. The application of two and three isotherm models shows that Langmuir-Freundlich (n = 0.84, K = 0.0014 L.mg -1 , and q = 250 mg.g -1 ) and Sips (n = 0.84, K = 0.003 L.mg -1 , and q = 232.6 mg.g -1 ) were the suitable models. The results demonstrated that cotton waste can be used in the textile industry as a low-cost precursor for the AC synthesis and the removal of anionic dye from textile wastewater.

High surface area mesoporous activated carbon-alginate beads for efficient removal of methylene blue.

PubMed

Nasrullah, Asma; Bhat, A H; Naeem, Abdul; Isa, Mohamed Hasnain; Danish, Mohammed

2018-02-01

High surface area mesoporous activated carbon-alginate (AC-alginate) beads were successfully synthesized by entrapping activated carbon powder derived from Mangosteen fruit peel into calcium-alginate beads for methylene blue (MB) removal from aqueous solution. The structure and surface characteristics of AC-alginate beads were analyzed using Fourier transform infra-red (FTIR) spectroscopy, scanning electron microscopy (SEM) and surface area analysis (S BET ), while thermal properties were tested using thermogravimetric analysis (TGA). The effect of AC-alginate dose, pH of solution, contact time, initial concentration of MB solution and temperature on MB removal was elucidated. The results showed that the maximum adsorption capacity of 230mg/g was achieved for 100mg/L of MB solution at pH 9.5 and temperature 25°C. Furthermore, the adsorption of MB on AC-alginate beads followed well pseudo-second order equation and equilibrium adsorption data were better fitted by the Freundlich isotherm model. The findings reveal the feasibility of AC-alginate beads composite to be used as a potential and low cost adsorbent for removal of cationic dyes. Copyright © 2017 Elsevier B.V. All rights reserved.

Sudan azo dyes and Para Red degradation by prevalent bacteria of the human gastrointestinal tract☆

PubMed Central

Xu, Haiyan; Heinze, Thomas M.; Paine, Donald D.; Cerniglia, Carl E.; Chen, Huizhong

2018-01-01

Sudan azo dyes have genotoxic effects and ingestion of food products contaminated with Sudan I, II, III, IV, and Para Red could lead to exposure in the human gastrointestinal tract. In this study, we examined thirty-five prevalent species of human intestinal bacteria to evaluate their capacity to degrade Sudan dyes and Para Red. Among these tested bacterial strains, 23, 13, 33, 30, and 29 out of 35 species tested were able to reduce Sudan I, II, III, IV, and Para Red, respectively, to some extent. Bifidobacterium infantis, Clostridium indolis, Enterococcus faecalis, Lactobacillus rhamnosus, and Ruminococcus obeum were able to reduce completely all four tested Sudan dyes and Para Red. Escherichia coli and Peptostreptococcus magnus were the only two strains that were not able to reduce any of the tested Sudan dyes and Para Red to any significant extent. Metabolites of the reduction of the tested Sudan dyes and Para Red by E. faecalis were isolated and identified by HPLC and LC/ESI-MS analyses and compared with authentic standards. Thus it appears that the ability to reduce Sudan dyes and Para Red except Sudan II is common among bacteria in the human colon. PMID:19580882

Synthesis of carbon loaded γ-Fe2O3 nanocomposite and their applicability for the selective removal of binary mixture of dyes by ultrasonic adsorption based on response surface methodology.

PubMed

Saad, Muhammad; Tahir, Hajira

2017-05-01

The contemporary problems concerning water purification could be resolved by using nanosorbents. The present studies emphasis on the synthesis of γ-Fe 2 O 3 -activated carbon nanocomposites (γ-Fe 2 O 3 -NP-AC) by sol-gel method. The composition and surface morphology of them were studied by FTIR, EDS, SEM and XRD techniques. Moreover they were employed for the selective removal of binary mixture of dyes including reactive red 223 dye (RR) and Malachite Green dye (MG) by ultrasonic assisted adsorption method. Sonication is the act of applying sound energy to agitate particles in the sample. The ultrasonic frequencies (>20kHz) were used to agitate experimental solutions in current studies. The response surface methodology based on 5 factorial central composite design (CCD) was employed to investigate the optimum parameters of adsorption. The optimum operating parameters (OOP) including sonication time, solution pH, amount of adsorbent, concentration of RR and MG were estimated for the selective removal of mixture of dyes. On OOP conditions of RR, the % removal of RR and MG were observed to be 92.12% and 10.05% respectively. While at OOP of MG, the % removal of MG and RR were observed to be 85.32% and 32.13% from the mixture respectively. Moreover the mechanisms of adsorption of RR and MG on the γ-Fe 2 O 3 -NP-AC were also illustrated. The significance of the RR-γ-Fe 2 O 3 -NP-AC and MG-γ-Fe 2 O 3 -NP-AC adsorption models was affirmed by ANOVA test. The Pareto plots for the selective removal of the RR and MG from the binary mixture also confirm the significance of the factors. Isothermal studies were performed and RR adsorption was observed to follow Langmuir isotherm model whereas MG adsorption was observed to follow Freundlich model. Thermodynamic studies were conducted and the outcomes suggested the spontaneous nature of adsorption processes. The kinetic models were employed to study the kinetics of the process. It was observed that the system followed pseudo second order, intra-particle diffusion and Elovich models as represented by the R 2 values of the respective models. The comparative study from the previously studies revealed that the proposed method is amongst them is the most efficient method to eliminate RR and MG dyes from the aqueous medium. Therefore the current study will be useful in reducing the toxicity of RR and MG contaminated effluent. Copyright © 2016 Elsevier B.V. All rights reserved.

Insight into the effects of modifying chromophores on the performance of quinoline-based dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Mao, Mao; Wang, Jian-Bo; Liu, Xiu-Lin; Wu, Guo-Hua; Fang, Xia-Qin; Song, Qin-Hua

2018-02-01

A series of organic dyes based on quinoline as an electron-deficient π-linker, were designed and synthesized for dye sensitized solar cells (DSSC) application. These push-pull conjugated dyes, sharing same anchoring group with distinctive electron-rich donating groups such as N,N-diethyl (DEA-Q), 3,6-dimethoxy carbazole (CBZ-Q), bis(4-butoxyphenyl)amine (BPA-Q), were synthesized by Riley oxidation of sbnd CH3 followed by Knoevenagel condensation of the corresponding aldehyde precursors 2a-c with cyanoacrylic acid. The optical, electrochemical, theoretical calculation and photovoltaic properties with these three dyes were systematically investigated. Compared to DEA-Q and CBZ-Q, BPA-Q possesses better light harvesting properties with regard to extended conjugate length, red-shifted intramolecular charge transfer band absorption and broaden light-responsive IPCE spectrum, resulting in a greater short circuit photocurrent density output. BPA-Q also has improved open-circuit voltage due to the apparent large charge recombination resistance. Consequently, assembled with iodine redox electrolytes, the device with BPA-Q achieved the best overall conversion efficiency value of 3.07% among three dyes under AM 1.5G standard conditions. This present investigation demonstrates the importance of various N-substituent chromophores in the prevalent D-π-A type organic sensitizers for tuning the photovoltaic performance of their DSSCs.

Protein labeling with red squarylium dyes for analysis by capillary electrophoresis with laser-induced fluorescence detection.

PubMed

Yan, Weiying; Sloat, Amy L; Yagi, Shigeyuki; Nakazumi, Hiroyuki; Colyer, Christa L

2006-04-01

Two new red luminescent asymmetric squarylium dyes (designated "Red-1c and Red-3") have been shown to exhibit absorbance shifts to longer wavelengths upon the addition of protein, along with a concomitant increase in fluorescence emission. Specifically, the absorbance maxima for Red-1c and Red-3 dyes are 607 and 622 nm, respectively, in the absence of HSA, and 642 and 640 nm in the presence of HSA, making the excitation of their protein complexes feasible with inexpensive and robust diode lasers. Fluorescence emission maxima, in the presence of HSA, are 656 and 644 nm for Red-1c and Red-3, respectively. Because of the inherently low fluorescence of the dyes in their free state, Red-1c and Red-3 were used as on-column labels (that is, with the dye incorporated into the separation buffer), thus eliminating the need for sample derivatization prior to injection and separation. A comparison of precolumn and on-column labeling of proteins with these squarylium dyes revealed higher efficiencies and greater sensitivities for on-column labeling, which, when conducted with a basic, high-salt content buffer, permitted baseline resolution of a mixture of five model proteins. LOD for model proteins, such as transferrin, alpha-lactalbumin, BSA, and beta-lactoglobulin A and B, labeled with these dyes and analyzed by CE with LIF detection (CE-LIF) were found to be dependent upon dye concentration and solution pH, and are as low as 5 nM for BSA. Satisfactory linear relationships between peak height (or peak area) and protein concentration were obtained by CE-LIF for this on-column labeling method with Red-3 and Red-1c.

Adsorptive removal of dye using biochar derived from residual algae after in-situ transesterification: Alternate use of waste of biodiesel industry.

PubMed

Nautiyal, Piyushi; Subramanian, K A; Dastidar, M G

2016-11-01

The primary aim of this present study was to utilize the residual biomass (DB) of Spirulina platensis algae, left after in-situ transesterification, for biochar preparation. This is a solid waste residue of biodiesel industry. The biochar (BC) prepared was examined for its capacity to adsorb congo red dye from the aqueous solution. The results were compared with other adsorbents used in the study such as commercial activated carbon (AC), original algae biomass (AB) and DB. The results of proximate analysis of BC showed the decrease in the percentage of volatile matter and an increase in fixed carbon content compared to DB. The physico-chemical properties of BC were studied using elemental analysis, SEM, FTIR and XRD techniques. The AC and BC adsorbents showed better performance in removing 85.4% and 82.6% of dye respectively from solution compared to AB (76.6%) and DB (78.1%). The effect of initial dye concentration, adsorbent dosage and pH of solution on the adsorption phenomena was studied by conducting the batch adsorption experiments. The highest specific uptake for biochar was observed at acidic pH of 2 with 0.2 g/100 ml of adsorbent dosage and 90 mg/l of initial concentration. The equilibrium adsorption data were fitted to three isotherms, namely Langmuir, Freundlich and Temkin. Freundlich model proved to show the best suited results with value of correlation coefficient of 99.12%. Thus, the application of DB for production of biochar as potential adsorbent supports sustainability of algae biodiesel. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis and characterization of natural red dye from Caesalpinia sappan linn

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mulyanto, Subur, E-mail: subur.mulyanto@poltekba.ac.id; Department of Mechanical Engineering, State Polytechnic of Balikpapan, Jl. Soekarno-Hatta Km.8 Balikpapan; Suyitno,, E-mail: suyitno@uns.ac.id

The study reports the synthesis and characterization of natural red dye. The dyes were extracted from woods of Caesalpiniasappanlinn at varied temperatures of 70, 80, 90, and 100°C for three hours. The dry wood chips and water at a ratio of 6:1 were immersed in the reactor of 150 liters. The absorbance spectra of the natural red dyes were measured by ultra-violet-visible spectroscopy. Meanwhile, Fourier transform infrared spectroscopy was used to investigate the functional groups of the natural red dyes. In addition, the basic production cost was calculated and the fastness property towards cotton fabrics was investigated according to themore » Indonesia national standard of 105-C06:2010, 105-B01:2010, and 0288-2008. The results showed that the functional groups found the extracted red dyes indicated the complex bond of brazilein with peak absorbance at a wavelength of 538-540 nm. The extraction temperature also changed the functional group of brazilein. From the color, the absorbance peak, the functional groups, and the main production cost, the best parameter to synthesize the natural red dyes from Caesalpiniasappanlinn was at a temperature of 80°C for two hours. Moreover, the natural red dyes has the fastness to wash resistance, light resistance, and scrub resistance by 4-5, 4, and 3-4, respectively. However, further studies for synthesis the natural red dyes by using a continuous reactor are required to identify the naturally complex compounds in brazilein for improving the fastness properties and for reducing the cost.« less

Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual‐Color Flag

PubMed Central

Oliveira, Elisabete; Bértolo, Emilia; Núñez, Cristina; Pilla, Viviane; Santos, Hugo M.; Fernández‐Lodeiro, Javier; Fernández‐Lodeiro, Adrian; Djafari, Jamila; Capelo, José Luis

2017-01-01

Abstract Red and green are two of the most‐preferred colors from the entire chromatic spectrum, and red and green dyes are widely used in biochemistry, immunohistochemistry, immune‐staining, and nanochemistry applications. Selective dyes with green and red excitable chromophores can be used in biological environments, such as tissues and cells, and can be irradiated with visible light without cell damage. This critical review, covering a period of five years, provides an overview of the most‐relevant results on the use of red and green fluorescent dyes in the fields of bio‐, chemo‐ and nanoscience. The review focuses on fluorescent dyes containing chromophores such as fluorescein, rhodamine, cyanine, boron–dipyrromethene (BODIPY), 7‐nitobenz‐2‐oxa‐1,3‐diazole‐4‐yl, naphthalimide, acridine orange, perylene diimides, coumarins, rosamine, Nile red, naphthalene diimide, distyrylpyridinium, benzophosphole P‐oxide, benzoresorufins, and tetrapyrrolic macrocycles. Metal complexes and nanomaterials with these dyes are also discussed. PMID:29318095

Albumin binds self-assembling dyes as specific polymolecular ligands.

PubMed

Stopa, Barbara; Rybarska, Janina; Drozd, Anna; Konieczny, Leszek; Król, Marcin; Lisowski, Marek; Piekarska, Barbara; Roterman, Irena; Spólnik, Paweł; Zemanek, Grzegorz

2006-12-15

Self-assembling dyes with a structure related to Congo red (e.g. Evans blue) form polymolecular complexes with albumin. The dyes, which are lacking a self-assembling property (Trypan blue, ANS) bind as single molecules. The supramolecular character of dye ligands bound to albumin was demonstrated by indicating the complexation of dye molecules outnumbering the binding sites in albumin and by measuring the hydrodynamic radius of albumin which is growing upon complexation of self-assembling dye in contrast to dyes lacking this property. The self-assembled character of Congo red was also proved using it as a carrier introducing to albumin the intercalated nonbonding foreign compounds. Supramolecular, ordered character of the dye in the complex with albumin was also revealed by finding that self-assembling dyes become chiral upon complexation. Congo red complexation makes albumin less resistant to low pH as concluded from the facilitated N-F transition, observed in studies based on the measurement of hydrodynamic radius. This particular interference with protein stability and the specific changes in digestion resulted from binding of Congo red suggest that the self-assembled dye penetrates the central crevice of albumin.

Optical properties of natural dyes on the dye-sensitized solar cells (DSSC) performance

NASA Astrophysics Data System (ADS)

Pratiwi, D. D.; Nurosyid, F.; Supriyanto, A.; Suryana, R.

2016-11-01

This study reported several natural dyes for application in dye-sensitized solar cells (DSSC). This study aims was to determine the effect of optical absorption properties of natural dyes on efficiency of DSSC. The sandwich structure of DSSC consist of TiO2 as working electrode, carbon layer as counter electrode, natural dyes as photosensitizer, and electrolyte as electron transfer media. The natural dyes used in this experiment were extracted from dragon fruit anthocyanin, mangosteen peels anthocyanin, and red cabbage anthocyanin. The absorbance of dyes solutions and the adsorption of the dye on the surface of TiO2 were characterized using UV-Vis spectrophotometer, the quantum efficiency versus wavelength was characterized using incident photon-to-current efficiency (IPCE) measurement system, and the efficiency of DSSC was calculated using I-V meter. UV-Vis characteristic curves showed that wavelength absorption of anthocyanin dye of red cabbage was 450 - 580 nm, anthocyanin of mangosteen peels was 400 - 480 nm, and anthocyanin of dragon fruit was 400 - 650 nm. Absorption spectra of the dye adsorption on the surface of TiO2 which was resulted in the highest absorbance of red cabbage anthocyanin. IPCE characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted quantum efficiency of 0.058%; 0.047%; and 0.043%, respectively at wavelength maximum about 430 nm. I-V characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted efficiency of 0.054%; 0.042%; and 0.024%, respectively.

Biosorption potential of synthetic dyes by heat-inactivated and live Lentinus edodes CCB-42 immobilized in loofa sponges.

PubMed

Gimenez, Gabriela Gregolin; Ruiz, Suelen Pereira; Caetano, Wilker; Peralta, Rosane Marina; Matioli, Graciette

2014-12-01

Lentinus edodes CCB-42 was immobilized in loofa sponges and applied to the biosorption of the synthetic dyes congo red, bordeaux red and methyl violet. Live immobilized microorganisms achieved average decolorations of congo red, bordeaux red and methyl violet of 97.8, 99.7 and 90.6 %, respectively. The loofa sponge was the support and the coadjuvant promoting dye adsorption. The biosorption conditions were optimized for each dye, yielding 30 °C, pH 5.0 and a 12 h reaction time for congo red; 25 °C, pH 3.0 and 36 h for bordeaux red; and 25 °C, pH 8.0 and 24 h for methyl violet. Operational stability was evaluated over five consecutive cycles, with both bordeaux red and congo red exhibiting decolorations above 90 %, while the decoloration of methyl violet decreased after the third cycle. In the sixth month of storage, congo red, bordeaux red and methyl violet had decolorations of 93.1, 79.4 and 73.8 %, respectively. Biosorption process best fit the pseudo-second-order kinetic and Freundlich isotherm models. Maximum biosorption capacity of heat-treated L. edodes immobilized in loofa sponge was determined as 143.678, 500.00 and 381.679 mg/g for congo red, bordeaux red and methyl violet, respectively. Treatment with immobilized L. edodes reduced the phytotoxicity of the medium containing dyes. FT-Raman experiments suggested the occurrence of interactions between loofa sponge fibers, L. edodes and dye. L. edodes CCB-42 immobilized in loofa sponges represents a promising new mode of treatment of industrial effluents.

Adsorption of dyes by ACs prepared from waste tyre reinforcing fibre. Effect of texture, surface chemistry and pH.

PubMed

Acevedo, Beatriz; Rocha, Raquel P; Pereira, Manuel F R; Figueiredo, José L; Barriocanal, Carmen

2015-12-01

This paper compares the importance of the texture and surface chemistry of waste tyre activated carbons in the adsorption of commercial dyes. The adsorption of two commercial dyes, Basic Astrazon Yellow 7GLL and Reactive Rifafix Red 3BN on activated carbons made up of reinforcing fibres from tyre waste and low-rank bituminous coal was studied. The surface chemistry of activated carbons was modified by means of HCl-HNO3 treatment in order to increase the number of functional groups. Moreover, the influence of the pH on the process was also studied, this factor being of great importance due to the amphoteric characteristics of activated carbons. The activated carbons made with reinforcing fibre and coal had the highest SBET, but the reinforcing fibre activated carbon samples had the highest mesopore volume. The texture of the activated carbons was not modified upon acid oxidation treatment, unlike their surface chemistry which underwent considerable modification. The activated carbons made with a mixture of reinforcing fibre and coal experienced the largest degree of oxidation, and so had more acid surface groups. The adsorption of reactive dye was governed by the mesoporous volume, whilst surface chemistry played only a secondary role. However, the surface chemistry of the activated carbons and dispersive interactions played a key role in the adsorption of the basic dye. The adsorption of the reactive dye was more favored in a solution of pH 2, whereas the basic dye was adsorbed more easily in a solution of pH 12. Copyright © 2015 Elsevier Inc. All rights reserved.

Molecular design of boronic acid-functionalized squarylium cyanine dyes for multiple discriminant analysis of sialic acid in biological samples: selectivity toward monosaccharides controlled by different alkyl side chain lengths.

PubMed

Ouchi, Kazuki; Colyer, Christa L; Sebaiy, Mahmoud; Zhou, Jin; Maeda, Takeshi; Nakazumi, Hiroyuki; Shibukawa, Masami; Saito, Shingo

2015-02-03

We designed a new series of boronic acid-functionalized squarylium cyanine dyes (SQ-BA) with different lengths of alkyl chain residues, suitable for multiple discriminant analysis (MDA) of sialic acid (Neu5Ac) in biological samples. The SQ-BA dyes form aggregates based on hydrophobic interactions, which result in quenched fluorescence in aqueous solutions. When the boronic acid binds with saccharides, the fluorescence intensity increases as a result of dissociation to the emissive monomeric complex. We inferred that different dye aggregate structures (H-aggregates and J-aggregates) were induced depending on the alkyl chain length, so that monosaccharides would be recognized in different ways (especially, multipoint interaction with J-aggregates). A distinctive emission enhancement of SQ-BA dyes with shorter-alkyl-chains in the presence of Neu5Ac was observed (2.4-fold fluorescence enhancement; with formation constant 10(1.7) M(-1)), with no such enhancement for SQ-BA dyes with longer-alkyl-chain. In addition, various enhancement factors for other monosaccharides were observed depending on the alkyl chain length. Detailed thermodynamic and NMR studies of the SQ-BA complexes revealed the unique recognition mechanism: the dye aggregate with a shorter-alkyl-chain causes the slipped parallel structure and forms a stable 2:1 complex with Neu5Ac, as distinct from longer-alkyl-chain dyes, which form a 1:1 monomeric complex. MDA using the four SQ-BA dyes was performed for human urine samples, resulting in the successful discrimination between normal and abnormal Neu5Ac levels characteristic of disease. Thus, we successfully controlled various responses to similar monosaccharides with a novel approach that chemically modified not the boronic acid moiety itself but the length of the alkyl chain residue attached to the dye in order to generate specificity.

Performance of Natural Dye and Counter Electrode from Robusta Coffee Beans Peel Waste for Fabrication of Dye-Sensitized Solar Cell (DSSC)

NASA Astrophysics Data System (ADS)

Setiawan, T.; Subekti, W. Y.; Nur'Adya, S. S.; Ilmiah, K.; Ulfa, S. M.

2018-01-01

The DSSC prototype using activated carbon (AC) and natural dye from Robusta coffee bean peels have been investigated. The natural dye obtained from the extraction of Robusta coffee bean peels is identified as anthocyanin by UV-Vis spectrophotometer at maximum wavelength 219.5 nm and 720.0 nm in methanol. From the FT-IR analysis, the vibration of O-H observed at 3385 cm-1, C=O at 1618 cm-1, and C-O-C at 1065 cm-1. The counter electrode prepared by calcined the peels at 300°C. Surface analyser of AC showed the larger surface area compared prior activation. The DSSC prototype was prepared using FTO glass (2x2 cm) coated with carbon paste in various thickness. The working electrode is coated with the TiO2 paste. The optimum voltage measured was 395mV (300 μL of CA), 334 mV (200 μL AC), and 254 mV (100 μL AC). From this result, we understand that the thickness of counter electrode influent the voltage of the DSSC.

Certification procedures for sirius red F3B (CI 35780, Direct red 80).

PubMed

Dapson, R W; Fagan, C; Kiernan, J A; Wickersham, T W

2011-06-01

Sirius red F3B (CI 35780, Direct red 80) is a polyazo dye used principally in staining methods for collagen and amyloid. For certification by the Biological Stain Commission, a sample of the dye must exhibit an absorption spectrum of characteristic shape with a maximum at 528-529 nm, a small shoulder near 500 nm and narrow peaks at 372, 281-282 and 230-235 nm. Spot tests (color changes with addition of concentrated H(2)SO(4) or HCl and subsequent dilution or neutralization) also are applied. The dye must perform satisfactorily in the picro-sirius red method for collagen by providing red staining of all types of collagen with yellow and green birefringence of fibers. Llewellyn's alkaline sirius red method applied to tissue known to contain amyloid must show red coloration of the products with green birefringence. Dye content, which does not influence significantly the staining properties of sirius red F3B, is not assayed.

Performance of dye-sensitized solar cells fabricated with extracts from fruits of ivy gourd and flowers of red frangipani as sensitizers

NASA Astrophysics Data System (ADS)

Shanmugam, Vinoth; Manoharan, Subbaiah; Anandan, Sambandam; Murugan, Ramaswamy

2013-03-01

Natural dyes extracted from fruits of ivy gourd and flowers of red frangipani were used as sensitizers to fabricate dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FTIR), Fourier transform Raman (FT-Raman) and liquid chromatography-mass spectrometry (LC-MS) studies indicated the presence of β-carotene in the fruits of ivy gourd and anthocyanins in the flowers of red frangipani. The extract of the flowers of red frangipani exhibits higher photosensitized performance compared to the fruits of ivy gourd and this is due to the better charge transfer between the dyes of flowers of red frangipani and the TiO2 photoanode surface.

Analysis of Chameleonic Change of Red Cabbage Depending on Broad pH Range for Dye-Sensitized Solar Cells.

PubMed

Park, Kyung Hee; Kim, Tae Young; Ko, Hyun Seok; Han, Eun Mi; Lee, Suk-Ho; Kim, Jung-Hun; Lee, Jae Wook

2015-08-01

Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from red cabbage as a sensitizer. In this work, we investigated the adsorption characteristics and the electrochemical behavior for harvesting sunlight and electron transfer in red cabbage DSSCs under different solvents and pH. For the red cabbage dye-sensitized electrode adsorbed at pH 3.5, the solar cell yields a short-circuit current density (Jsc) of 1.60 mA/cm2, a photovoltage (Vcc) of 0.46 V, and a fill factor of 0.55, corresponding to an energy conversion efficiency (η) of 0.41%.

Bright and photostable cyanine-styryl chromophores with green and red fluorescence colour for DNA staining

NASA Astrophysics Data System (ADS)

Bohländer, Peggy R.; Wagenknecht, Hans-Achim

2015-12-01

The synthesis and optical characterisation of a series of green- and red-emitting cyanine and cyanine-styryl dyes is presented that were developed based on the cyanine-indole-quinolinium and based on the thiazole red type structure. For the green emitting fluorophores the quinolinium part was replaced by a pyridinium group. The bridge to the indole group was attached either to the 2-position or to the 4-position of the pyridinium moiety. For the red-emitting dyes the connection to the indole moiety is at the 4-position of the quinolinium part. In each set of dyes a methyl group at the indole-NH and/or a phenyl group at the 2-position of the indole part were introduced to tune the optical properties and photostability. Additionally, two dyes were modified with a cyano group to tune the photophysical properties and to enhance the photostabilities. The developed dyes show good photostabilities and bright green or red fluorescence intensities in the presence of DNA. Thus, these dyes represent important and promising candidates for fluorescent molecular imaging of nucleic acids inside living cells.

Optical properties of anthocyanin dyes on TiO2 as photosensitizers for application of dye-sensitized solar cell (DSSC)

NASA Astrophysics Data System (ADS)

Ahliha, A. H.; Nurosyid, F.; Supriyanto, A.; Kusumaningsih, T.

2018-03-01

Dye-sensitized solar cell (DSSC) is one of the alternative energy that can convert light energy into electrical energy. The component of DSSC consists of FTO substrates, TiO2, electrolyte, dye sensitizer, and counter electrode. This study aim was to determine the effect of optical properties of anthocyanin dyes on efficiency of DSSC. The dye sensitizer used can be extracted from anthocyanin pigments such as dragon fruit, black rice, and red cabbage. The red cabbage sensitizer shows lower absorbance value in the visible range (450-580 nm), than dragon fruit and black rice. The chemical structure of each dye molecules has an R group (carbonyl and hydroxyl) that forms a bond with the oxide layer. Red cabbage dye cell has the highest efficiency, 0.06% then dragon fruit and black rice, 0.02% and 0.03%.

Identification of the monobrominated derivative of Acid Red 52 (Food Red No. 106) in pickled vegetables.

PubMed

Ochi, Naoki; Okuda, Tetsuya; Fujii, Hisashi

2016-09-01

Two unknown dyes (purple and purplish-red) were detected by TLC in two pickled vegetable (sakura-zuke daikon) samples containing Acid Red 52 (AR) and New Coccine as food colorants. HPLC with diode-array detection and LC/MS analyses suggested that the purple dye is monobrominated AR and the purplish-red dye is its N-desethyl derivative, which would be generated mainly during sample preparation. For the identification of the purple dye, a reference compound was prepared by bromination of AR followed by isolation of the monobrominated AR, the structure of which was elucidated as 4'-brominated AR (4'BrAR) by LC/ToF-MS and (1)H-NMR spectroscopy. The purple dye was confirmed as 4'BrAR by comparison of its retention time, ultraviolet-visible spectrum and mass spectrum with those of the prepared reference compound. To our knowledge, this is the first report of the detection of 4'BrAR in foods.

Novel Blue Organic Dye for Dye-Sensitized Solar Cells Achieving High Efficiency in Cobalt-Based Electrolytes and by Co-Sensitization.

PubMed

Hao, Yan; Saygili, Yasemin; Cong, Jiayan; Eriksson, Anna; Yang, Wenxing; Zhang, Jinbao; Polanski, Enrico; Nonomura, Kazuteru; Zakeeruddin, Shaik Mohammed; Grätzel, Michael; Hagfeldt, Anders; Boschloo, Gerrit

2016-12-07

Blue and green dyes as well as NIR-absorbing dyes have attracted great interest because of their excellent ability of absorbing the incident photons in the red and near-infrared range region. A novel blue D-π-A dye (Dyenamo Blue), based on the diketopyrrolopyrrole (DPP)-core, has been designed and synthesized. Assembled with the cobalt bipyridine-based electrolytes, the device with Dyenamo Blue achieved a satisfying efficiency of 7.3% under one sun (AM1.5 G). The co-sensitization strategy was further applied on this blue organic dye together with a red D-π-A dye (D35). The successful co-sensitization outperformed a panchromatic light absorption and improved the photocurrent density; this in addition to the open-circuit potential result in an efficiency of 8.7%. The extended absorption of the sensitization and the slower recombination reaction between the blue dye and TiO 2 surface inhibited by the additional red sensitizer could be the two main reasons for the higher performance. In conclusion, from the results, the highly efficient cobalt-based DSSCs could be achieved with the co-sensitization between red and blue D-π-A organic dyes with a proper design, which showed us the possibility of applying this strategy for future high-performance solar cells.

Coumarin-indole conjugate donor-acceptor system: Synthesis, photophysical properties, anion sensing ability, theoretical and biological activity studies of two coumarin-indole based push-pull dyes

NASA Astrophysics Data System (ADS)

Aksungur, Tuğçe; Aydıner, Burcu; Seferoğlu, Nurgül; Özkütük, Müjgan; Arslan, Leyla; Reis, Yasemin; Açık, Leyla; Seferoğlu, Zeynel

2017-11-01

Two coumarin-indole conjugate fluorescent dyes having donor-acceptor-donor (D-A-D) (CI-1 and CI-2) were synthesized, and characterized using IR, 1H/13C NMR and HRMS. The absorption and emission properties of the dyes were determined in different solvents. The anion sensitivity and selectivity of the dyes were studied with some anions (CN-, F-, AcO-, Cl-, Br-, I-, HSO4- and H2PO4-) in DMSO, and their interaction mechanisms were evaluated by spectrophotometric and 1H NMR titration techniques. In addition, the molecular and electronic structures of CI-1, as well as the molecular complexes of CI-1, formed with the anions (F- and AcO-), were obtained theoretically and confirmed by DFT and TD-DFT calculations. CI-1 behaves as a colorimetric chemosensor for selective and sensitive detection of CN- in DMSO/H2O (9:1) over other competing anions such as F- and AcO-. However, only CN- interacts with chromophore CI-2 via Michael addition and the main absorption maxima shifts hypsochromically with an observed distinctive color change from orange to yellow. For using as a optic dye, the thermal stability properties of the dyes was determined by TGA (Thermal Gravimetric Analysis). Antimicrobial, antifungal and DNA-ligand interaction studies of the dyes were also examined. The dyes cause conformational changes on DNA and selectively bind to nucleotides of A/A and G/G.

Adsorption of dissolved Reactive red dye from aqueous phase onto activated carbon prepared from agricultural waste.

PubMed

Senthilkumaar, S; Kalaamani, P; Porkodi, K; Varadarajan, P R; Subburaam, C V

2006-09-01

The adsorption of Reactive red dye (RR) onto Coconut tree flower carbon (CFC) and Jute fibre carbon (JFC) from aqueous solution was investigated. Adsorption studies were carried out at different initial dye concentrations, initial solution pH and adsorbent doses. The kinetic studies were also conducted; the adsorption of Reactive red onto CFC and JFC followed pseudosecond-order rate equation. The effective diffusion coefficient was evaluated to establish the film diffusion mechanism. Quantitative removal of Reactive red dye was achieved at strongly acidic conditions for both the carbons studied. The adsorption isotherm data were fitted well to Langmuir isotherm and the adsorption capacity were found to be 181.9 and 200 mg/g for CFC and JFC, respectively. The overall rate of dye adsorption appeared to be controlled by chemisorption, in this case in accordance with poor desorption studies.

A non-toxic fluorogenic dye for mitochondria labeling.

PubMed

Han, Junyan; Han, Myung Shin; Tung, Ching-Hsuan

2013-11-01

Mitochondria, powerhouses of cells, are responsible for many critical cellular functions, such as cell energy metabolism, reactive oxygen species production, and apoptosis regulation. Monitoring mitochondria morphology in live cells temporally and spatially could help with the understanding of the mechanisms of mitochondrial functional regulation and the pathogenesis of mitochondria-related diseases. A novel non-cytotoxic fluorogenic compound, AcQCy7, was developed as a mitochondria-specific dye. AcQCy7 emitted no fluorescent signal outside of cells, but it became fluorescent after intracellular hydrolysis of the acetyl group. The hydrolyzed fluorescent product was well retained in mitochondria, enabling long-lasting fluorescence imaging of mitochondria without cell washing. A 2-day culture study using AcQCy7 showed no sign of cytotoxicity, whereas a commonly used mitochondria-staining probe, Mitochondria Tracker Green, caused significant cell death even at a much lower concentration. Apoptosis-causing mitochondria fission was monitored clearly in real time by AcQCy7. A simple add-and-read mitochondria specific dye AcQCy7 has been validated in various cell models. Bright mitochondria specific fluorescent signal in treated cells lasted several days without noticeable toxicity. The probe AcQCy7 has been proofed to be a non-toxic agent for long-term mitochondria imaging. © 2013.

A Non-Toxic Fluorogenic Dye for Mitochondria Labeling

PubMed Central

Han, Junyan; Han, Myung Shin; Tung, Ching-Hsuan

2013-01-01

Background Mitochondria, powerhouses of cells, are responsible for many critical cellular functions, such as cell energy metabolism, reactive oxygen species production, and apoptosis regulation. Monitoring mitochondria morphology in live cells temporally and spatially could help with understanding of the mechanisms of mitochondrial functional regulation and the pathogenesis of mitochondria-related diseases. Methods A novel non-cytotoxic fluorogenic compound, AcQCy7, was developed as a mitochondria-specific dye. Results AcQCy7 emitted no fluorescent signal outside of cells, but it became fluorescent after intracellular hydrolysis of the acetyl group. The hydrolyzed fluorescent product was well retained in mitochondria, enabling long-lasting fluorescence imaging of mitochondria without cell washing. A 2-day culture study using AcQCy7 showed no sign of cytotoxicity, whereas a commonly used mitochondria-staining probe, Mitochondria Tracker Green, caused significant cell death even at a much lower concentration. Apoptosis-causing mitochondria fission was monitored clearly in real time by AcQCy7. Conclusions A simple add-and-read mitochondria specific dye AcQCy7 has been validated in various cell models. Bright mitochondria specific fluorescent signal in treated cells lasted several days without noticeable toxicity. General Significance The probe AcQCy7 has been proofed to be a non-toxic agent for long-term mitochondria imaging. PMID:23850639

Comparison of static and shake culture in the decolorization of textile dyes and dye effluents by Phanerochaete chrysoporium.

PubMed

Sani, R K; Azmi, W; Banerjee, U C

1998-01-01

Decolorization of several dyes (Red HE-8B, Malachite Green, Navy Blue HE-2R, Magenta, Crystal Violet) and an industrial effluent with growing cells of Phanerochaete chrysosporium in shake and static culture was demonstrated. All the dyes and the industrial effluent were decolorized to some extent with varying percentages of decolorization (20-100%). The rate of decolorization was very rapid with Red HE-8B, an industrial dye. Decolorization rates for all the dyes in static condition were found to be less than the shake culture and also dependent on biomass concentration.

Multiexcitation Fluorogenic Labeling of Surface, Intracellular, and Total Protein Pools in Living Cells

PubMed Central

2016-01-01

Malachite green (MG) is a fluorogenic dye that shows fluorescence enhancement upon binding to its engineered cognate protein, a fluorogen activating protein (FAP). Energy transfer donors such as cyanine and rhodamine dyes have been conjugated with MG to modify the spectral properties of the fluorescent complexes, where the donor dyes transfer energy through Förster resonance energy transfer to the MG complex resulting in binding-conditional fluorescence emission in the far-red region. In this article, we use a violet-excitable dye as a donor to sensitize the far-red emission of the MG-FAP complex. Two blue emitting fluorescent coumarin dyes were coupled to MG and evaluated for energy transfer to the MG-FAP complex via its secondary excitation band. 6,8-Difluoro-7-hydroxycoumarin-3-carboxylic acid (Pacific blue, PB) showed the most efficient energy transfer and maximum brightness in the far-red region upon violet (405 nm) excitation. These blue-red (BluR) tandem dyes are spectrally varied from other tandem dyes and are able to produce fluorescence images of the MG-FAP complex with a large Stokes shift (>250 nm). These dyes are cell-permeable and are used to label intracellular proteins. Used together with a cell-impermeable hexa-Cy3-MG (HCM) dye that labels extracellular proteins, we are able to visualize extracellular, intracellular, and total pools of cellular protein using one fluorogenic tag that combines with distinct dyes to effect different spectral characteristics. PMID:27159569

One step effective removal of Congo Red in chitosan nanoparticles by encapsulation

NASA Astrophysics Data System (ADS)

Alver, Erol; Bulut, Mehmet; Metin, Ayşegül Ülkü; Çiftçi, Hakan

2017-01-01

Chitosan nanoparticles (CNPs) were prepared with ionotropic gelation between chitosan and tripolyphosphate for the removal of Congo Red. The production of chitosan nanoparticles and the dye removal process was carried out in one-step. The removal efficiency of Congo Red by encapsulation within chitosan from the aqueous solution and its storage stability are examined at different pH values. The influence of some parameters such as the initial dye concentration, pH value of the dye solution, electrolyte concentration, tripolyphosphate concentration, mixing time and speed on the encapsulation is examined. Congo Red removal efficiency and encapsulation capacity of chitosan nanoparticles were determined as above 98% and 5107 mg Congo Red/g chitosan, respectively.

Role of the oxyallyl substructure in the near infrared (NIR) absorption in symmetrical dye derivatives: A computational study.

PubMed

Prabhakar, Ch; Chaitanya, G Krishna; Sitha, Sanyasi; Bhanuprakash, K; Rao, V Jayathirtha

2005-03-24

It is well-known from experimental studies that the oxyallyl-substructure-based squarylium and croconium dyes absorb in the NIR region of the spectrum. Recently, another dye has been reported (J. Am. Chem. Soc. 2003, 125, 348) which contains the same basic chromophore, but the absorption is red-shifted by at least 300 nm compared to the former dyes and is observed near 1100 nm. To analyze the reasons behind the large red shift, in this work we have carried out symmetry-adapted cluster-configuration interaction (SAC-CI) studies on some of these NIR dyes which contain the oxyallyl substructure. From this study, contrary to the earlier reports, it is seen that the donor groups do not seem to play a major role in the red-shift of the absorption. On the other hand, on the basis of the results of the high-level calculations carried out here and using qualitative molecular orbital theory, it is observed that the orbital interactions play a key role in the red shift. Finally, design principles for the oxyallyl-substructure-based NIR dyes are suggested.

Evaluation of Aluminium Dross as Adsorbent for Removal of Carcinogenic Congo Red Dye in Wastewater

NASA Astrophysics Data System (ADS)

Zakaria, Mohamad Zulfika Hazielim b.; Zauzi, Nur Syuhada Ahmad; Baini, Rubiyah; Sutan, Norsuzailina Mohamed; Rezaur Rahman, Md

2017-06-01

In this study, aluminium dross waste generated from aluminium smelting industries was employed as adsorbent in removing of congo red dye in aqueous solution. The raw aluminium dross as adsorbent was characterized using Scanning Electron Microscope (SEM), Brunauer-Emmett-Teller (BET) for surface area and X-Ray Fluorescence (XRF) Spectroscopy. Adsorption experiments were carried out by batch system at different adsorbent mass, pH, and initial dye concentration. The results showed that the per cent removal of dye increased as adsorbent mass increased. It was found that 0.4 gram of adsorbent can remove approximately 100 % of dye at pH 9 for dye concentration 20 and 40 ppm. Therefore, it can be concluded that raw aluminium dross without undergone any treatment can be effectively used for the adsorption of congo red in textile wastewater related industries.

On the molecular interaction between lactoferrin and the dye Red HE-3B. A novel approach for docking a charged and highly flexible molecule to protein surfaces

NASA Astrophysics Data System (ADS)

Grasselli, Mariano; Cascone, Osvaldo; Anspach, F. Birger; Delfino, Jose M.

2002-12-01

Lactoferrin (Lf) is a non-heme, iron binding protein present in many physiological fluids of vertebrates where its main role is the microbicidal activity. It has been isolated by different methods, including dye-affinity chromatography. Red HE-3B is one of the most common triazinic dyes applied in protein purification, but scant knowledge is available on structural details and on the energetics of its interaction with proteins. In this work we present a computational approach useful for identifying possible binding sites for Red HE-3B in apo and holo forms of Lfs from human and bovine source. A new geometrical description of Red HE-3B is introduced which greatly simplifies the conformational analysis. This approach proved to be of particular advantage for addressing conformational ensembles of highly flexible molecules. Predictions from this analysis were correlated with experimentally observed dye-binding sites, as mapped by protection from proteolysis in Red HE-3B/Lf complexes. This method could bear relevance for the screening of possible dye-binding sites in proteins whose structure is known and as a potential tool for the design of engineered protein variants which could be purified by dye-affinity chromatography.

On the molecular interaction between lactoferrin and the dye Red HE-3b. A novel approach for docking a charged and highly flexible molecule to protein surfaces.

PubMed

Grasselli, Mariano; Cascone, Osvaldo; Birger Anspach, F; Delfino, Jose M

2002-12-01

Lactoferrin (Lf) is a non-heme, iron binding protein present in many physiological fluids of vertebrates where its main role is the microbicidal activity. It has been isolated by different methods, including dye-affinity chromatography. Red HE-3B is one of the most common triazinic dyes applied in protein purification, but scant knowledge is available on structural details and on the energetics of its interaction with proteins. In this work we present a computational approach useful for identifying possible binding sites for Red HE-3B in apo and holo forms of Lfs from human and bovine source. A new geometrical description of Red HE-3B is introduced which greatly simplifies the conformational analysis. This approach proved to be of particular advantage for addressing conformational ensembles of highly flexible molecules. Predictions from this analysis were correlated with experimentally observed dye-binding sites, as mapped by protection from proteolysis in Red HE-3B/Lf complexes. This method could bear relevance for the screening of possible dye-binding sites in proteins whose structure is known and as a potential tool for the design of engineered protein variants which could be purified by dye-affinity chromatography.

The increased flexibility of CDR loops generated in antibodies by Congo red complexation favors antigen binding.

PubMed

Krol, Marcin; Roterman, Irena; Drozd, Anna; Konieczny, Leszek; Piekarska, Barbara; Rybarska, Janina; Spolnik, Paweł; Stopa, Barbara

2006-02-01

The dye Congo red and related self-assembling compounds were found to stabilize immune complexes by binding to antibodies currently engaged in complexation to antigen. In our simulations, it was shown that the site that becomes accessible for binding the supramolecular dye ligand is located in the V domain, and is normally occupied by the N-terminal polypeptide chain fragment. The binding of the ligand disrupts the beta-structure in the domain, increasing the plasticity of the antigen-binding site. The higher fluctuation of CDR-bearing loops enhances antigen binding, and allows even low-affinity antibodies to be engaged in immune complexes. Experimental observations of the enhancement effect were supported by theoretical studies using L lambda chain (4BJL-PDB identification) and the L chain from the complex of IgM-rheumatoid factor bound to the CH3 domain of the Fc fragment (1ADQ-PDB identification) as the initial structures for theoretical studies of dye-induced changes. Commercial IgM-type rheumatoid factor (human) and sheep red blood cells with coupled IgG (human) were used for experimental tests aimed to reveal the dye-enhancement effect in this system. The specificity of antigen-antibody interaction enhanced by dye binding was studied using rabbit anti-sheep red cell antibodies to agglutinate red cells of different species. Red blood cells of hoofed mammals (horse, goat) showed weak enhancement of agglutination in the presence of Congo red. Neither agglutination nor enhancement were observed in the case of human red cells. The dye-enhancement capability in the SRBC-antiSRBC system was lost after pepsin-digestion of antibodies producing (Fab)2 fragments still agglutinating red cells. Monoclonal (myeloma) IgG, L lambda chain and ovoalbumin failed to agglutinate red cells, as expected, and showed no enhancement effect. This indicates that the enhancement effect is specific.

Treatment of industrial wastewater containing Congo Red and Naphthol Green B using low-cost adsorbent.

PubMed

Attallah, M F; Ahmed, I M; Hamed, Mostafa M

2013-02-01

The present work investigates the potential use of metal hydroxides sludge (MHS) generated from hot dipping galvanizing plant for adsorption of Congo Red and Naphthol Green B dyes from aqueous solutions. Characterization of MHS included infrared and X-ray fluorescence analysis. The effect of shaking time, initial dye concentration, temperature, adsorbent dosage and pH has been investigated. The results of adsorption experiments indicate that the maximum capacity of Congo Red and Naphthol Green B dyes at equilibrium (q(e)) and percentage of removal at pH 6 are 40 mg/g, 93 %, and 10 mg/g, 52 %, respectively. Some kinetic models were used to illustrate the adsorption process of Congo Red and Naphthol Green B dyes using MHS waste. Thermodynamic parameters such as (ΔG, ΔS, and ΔH) were also determined.

The color removal of dye wastewater by magnesium chloride/red mud (MRM) from aqueous solution.

PubMed

Wang, Qi; Luan, Zhaokun; Wei, Ning; Li, Jin; Liu, Chengxi

2009-10-30

In this study, the MgCl2/red mud system (MRM) was used to investigate the color removal efficiency of dye solutions. Parameters such as the effect of the dosage of red mud (RM) and MgCl2 have been studied. The effect of pH on the conversion rate of Mg2+ has also been studied. The color removal efficiency of MRM was compared with that of PAC/RM and PAC/NaOH. Meanwhile, the color removal efficiency of RM was compared with that of NaOH. The results show that the MRM system can remove more than 98% of the coloring material at a dosage of 25 g RM/L dye solution and a volume of 1.5 mL MgCl2/L dye solution in the decolorization process of reactive dye, acid dye and direct dye. The color removal efficiency was better than PAC/RM and PAC/NaOH system. The adsorption data have been analyzed using Langmuir and Freundlich isotherms. The results indicated that both models provide the best correlation of the experimental data. The decolorization mechanism of MRM was discussed, too. The MRM system was a viable alternative to some of the more conventional forms of chemical treatment of dye solutions and also provided another way to make use of industrial waste red mud.

Calcium Sensitive Fluorescent Dyes Fluo-4 and Fura Red under Pressure: Behaviour of Fluorescence and Buffer Properties under Hydrostatic Pressures up to 200 MPa.

PubMed

Schneidereit, D; Vass, H; Reischl, B; Allen, R J; Friedrich, O

2016-01-01

The fluorescent Ca2+ sensitive dyes Fura Red (ratiometric) and Fluo-4 (non-ratiometric) are widely utilized for the optical assessment of Ca2+ fluctuations in vitro as well as in situ. The fluorescent behavior of these dyes is strongly depends on temperature, pH, ionic strength and pressure. It is crucial to understand the response of these dyes to pressure when applying calcium imaging technologies in the field of high pressure bioscience. Therefore, we use an optically accessible pressure vessel to pressurize physiological Ca2+-buffered solutions at different fixed concentrations of free Ca2+ (1 nM to 25.6 μM) and a specified dye concentration (12 μM) to pressures of 200 MPa, and record dye fluorescence intensity. Our results show that Fluo-4 fluorescence intensity is reduced by 31% per 100 MPa, the intensity of Fura Red is reduced by 10% per 100 MPa. The mean reaction volume for the dissociation of calcium from the dye molecules [Formula: see text] is determined to -17.8 ml mol-1 for Fluo-4 and -21.3 ml mol-1 for Fura Red. Additionally, a model is presented that is used to correct for pressure-dependent changes in pH and binding affinity of Ca2+ to EGTA, as well as to determine the influence of these changes on dye fluorescence.

Effect of electron withdrawing unit for dye-sensitized solar cell based on D-A-π-A organic dyes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Dong Yuel; Chang, Dong Min; Kim, Young Sik, E-mail: youngkim@hongik.ac.kr

2014-10-15

Highlights: • To gain the red-shifted absorption spectra, withdrawing unit was substituted in dye. • By the introduction of additional withdrawing unit, LUMOs level of dye are decreased. • Decreasing LUMOs level of dye caused the red-shifted absorption spectra of dye. • Novel acceptor, DCRD, showed better photovoltaic properties than cyanoacetic acid. - Abstract: In this work, two novel D-A-π-A dye sensitizers with triarylamine as an electron donor, isoindigo and cyano group as electron withdrawing units and cyanoacetic acid and 2-(1,1-dicyanomethylene) rhodanine as an electron acceptor for an anchoring group (TICC, TICR) were designed and investigated with the ID6 dyemore » as the reference. The difference in HOMO and LUMO levels were compared according to the presence or absence of isoindigo in ID6 (TC and ID6). To gain insight into the factors responsible for photovoltaic performance, we used density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. Owing to different LUMO levels for each acceptor, the absorption band and molar extinction coefficient of each dye was different. Among the dyes, TICR showed more red-shifted and broader absorption spectra than other dyes and had a higher molar extinction coefficient than the reference. It is expected that TICR would show better photovoltaic properties than the other dyes, including the reference dye.« less

Decolourisation of Red 5 MB dye by microbes isolated from textile dye effluent.

PubMed

Subashini, P; Hiranmaiyadav, R; Premalatha, M S

2010-07-01

One of the major environmental problems is the presence of dye materials in textile wastewater, which need to be removed before releasing into the environment. Some dyes are toxic and carcinogenic in nature. The discharge of the textile effluent into rivers and lakes leads to higher BOD causing threat to aquatic life. Development of efficient dye degradation requires suitable strain and its use under favorable condition to realize the degradation potential. In this study, three microorganisms were isolated from the Red 5 MB dye containing textile wastewater. They were identified and tested for the dye decolourisation provided with different sugars as carbon source. The percentage of dye decolorized by Bacillus subtilis, Aspergillus flavus and Aspergillus fumigatus were found to be about 40%, 75% and 53.8% respectively.

Deep-red to near-infrared fluorescent dyes: Synthesis, photophysical properties, and application in cell imaging

NASA Astrophysics Data System (ADS)

Li, Qi; Liu, Weimin; Wu, Jiasheng; Zhou, Bingjiang; Niu, Guangle; Zhang, Hongyan; Ge, Jiechao; Wang, Pengfei

2016-07-01

More and more attention has been paid to the design of new fluorescent imaging agents with good photostability and water solubility, especially those with emissions in the deep-red and near-infrared regions. In this work, we designed and synthesized four novel fluorescent dyes with deep-red or NIR fluorescence by hybridizing coumarin and pyronin moieties based on our previous work. Introduction of carboxylic acid in the dyes not only imparted the dyes with water solubility but also provided a versatile sensing platform for designing the fluorescent probes and sensors of biomolecules. The photophysical properties of these new dyes were investigated through absorption and fluorescence spectroscopy. Cell imaging experiments showed that esterification products could selectively stain lysosomes with good photostability, thereby indicating that they could be useful in the development of fluorescent probes for bioimaging.

Extraction and Quantitation of FD&C Red Dye #40 from Beverages Containing Cranberry Juice: A College-Level Analytical Chemistry Experiment

ERIC Educational Resources Information Center

Rossi, Henry F., III; Rizzo, Jacqueline; Zimmerman, Devon C.; Usher, Karyn M.

2012-01-01

A chemical separation experiment can be an interesting addition to an introductory analytical chemistry laboratory course. We have developed an experiment to extract FD&C Red Dye #40 from beverages containing cranberry juice. After extraction, the dye is quantified using colorimetry. The experiment gives students hands-on experience in using solid…

Adsorption of allura red dye by cross-linked chitosan from shrimp waste.

PubMed

Sánchez-Duarte, Reyna G; Sánchez-Machado, Dalia I; López-Cervantes, Jaime; Correa-Murrieta, Ma A

2012-01-01

The present study was designed to evaluate the chitosan, which has been obtained by deacetylation of chitin, as a biosorbent. The chitin was isolated from fermented shrimp waste by an important local industrial food biopolymer. The aim of this work was the characterization of chitosan and preparation of cross-linked chitosan- tripolyphosphate (chitosan-TPP) beads for the removal of allura red food dye from aqueous solutions. Conditions of batch adsorption such as pH, time and adsorbent dose were examined. The effectiveness of cross-linked chitosan beads for dye removal was found to be higher for pH 2 (98%, percentage of dye removal) and tends to decrease at pHs of 3 to 11 (up to 49%). The values of percentage removal show that the adsorption capacity increases with time of contact and dosage of chitosan-TPP, but red dye adsorption is mainly influenced by pH level. The cross-linked chitosan-TPP beads can significantly adsorb allura red monoazo dye from aqueous solutions even at acidic pHs unlike raw chitosan beads that tend to dissolve in acidic solutions. Consequently, this modified chitosan has characteristics that allow minimization of environmental pollution and widening the valorization of shrimp waste.

Preparation of Activated Carbon/N-doped Titania Composite for Synergistic Adsorption-photocatalytic Oxidation of Batik Dye

NASA Astrophysics Data System (ADS)

Aziz, A. A.; Ibrahim, S.

2018-05-01

A synergetic improved composite TiO2 photocatalysts was successfully synthesized by using nitrogen (N) as a dopant and activated carbon (AC) as synergetic compound. Two different types of AC prepared from Garcinia mangostana shell and commercial AC obtained from palm shell were chosen as synergetic compound. Thus synthesized composites was further characterized by Brunauer-Emmett-Teller (BET) surface analyzer and UV-visible light spectroscope. The doping of N resulted in a better solar light utilization potential. Furthermore, synergizing with AC contributed for the improved BET surface area and pore size distribution. The synergetic adsorption-photocatalytic activity was investigated by removing a commercial batik dye namely Remazol Brilliant Blue (RBB) under direct solar irradiation. The synergetic experiments showed that commercial AC synergized with N-TiO2 resulted with a maximum removal efficiency of ∼80% in 6 h.

Investigating the effect of various extracting solvents on the potential use of red-apple skin (Malus domestica) as natural sensitizer for dye-sensitized solar cell

NASA Astrophysics Data System (ADS)

Saputro, Aldhi; Mizan, Adlan; Sofyan, Nofrijon; Yuwono, Akhmad Herman

2017-03-01

In the current investigation, the natural dye extracted from red-apple (Malus domestica) skin was used as natural sensitizer for dye sensitized solar cell (DSSC) application. The present study was specifically aimed at observing the effect of different solvents, i.e. deionized water, ethanol, and acidified ethanol, on the performance of the natural dye and thus the DSSC. For synthesis purposes, red-apple skin was peeled off, dried, crushed and furthermore extracted with ratio red-apple skin powder to solvent 1:20 w/v for 2 hours at 50°C under mechanical stirring. Subsequently, the resulting natural dyes with different solvents were examined by Fourier transform infrared (FTIR) to analyze their functional groups, UV-Vis spectroscopy to observe their absorption spectra for a wide range of wavelength, while TiO2 nanoparticle used as the semiconductor oxide layer in the device was characterized by field emission scanning electron microscope (FESEM). The FTIR results showed that the red-apple skin has anthocyanin group which functions as the sensitizer agent for photon energy absorption from the sunlight. The UV-Vis spectroscopy results showed that ethanol solvent has higher absorption of sunlight wavelength as compared to those of deionized water and acidified ethanol solvents. The performance test of the fabricated DSSC showed the prototype made of the red apple skin dye extracted by ethanol solvent can provide the highest open circuit voltage (Voc) up to 324 mV and efficiency around 0.046%. On the basis of investigation, it has been found that ethanol was the best solvent to extract anthocyanin from the red-apple skin.

Tuning the light emission of novel donor-acceptor phenoxazine dye-based materials towards the red spectral range

NASA Astrophysics Data System (ADS)

Damaceanu, Mariana-Dana; Constantin, Catalin-Paul

2018-04-01

A novel red fluorescent push-pull system able to generate an intramolecular charge-transfer (ICT) complex was synthesized. The novel dye (R-POX) combines some structural features which are rarely encountered in the design of other push-pull systems: hexyl-substituted phenoxazine as donor moiety, divinylketone as π-linker, and p-fluorobenzene as electron acceptor group. The relationship between the structural motif, photo-physical and electrochemical properties by UV-Vis absorption, photoluminescence and cyclic voltammetry was thoroughly investigated both as red dopant in poly(methylmethacrylate) (PMMA) or polyimide (PI) matrix, and non-doped host emitter. The molecular rigid cores of the synthesized dye formed supramolecular rod-like structures in condensed phase with a strong impact on the emissive centers. The aggregation was totally suppressed when the dye was used as dopant in an amorphous polymeric matrix, such as PMMA or PI. Electrochemical measurements revealed the dye ability for both hole and electron injection and transport. The fluorescence emission was found to be highly sensitive to solvent polarity, rendering blue-green, yellow, orange and red light emission in different organic solvents. The absolute fluorescence quantum yield reached 39.57% in solution, and dropped to 1.2% in solid state and to 14.01% when the dye was used as dopant in PMMA matrix. According to the available CIE 1931 standard, R-POX emitted pure and saturated red light of single wavelength with chromaticity coordinates very close to those of National Television System Committee (NTSC) standard red colour. The R-POX photo-optical features were compared to those of the commercial red emitter 6, 13-diphenylpentacene.

Sugarcane bagasse powder as biosorbent for reactive red 120 removals from aqueous solution

NASA Astrophysics Data System (ADS)

Ahmad, S.; Wong, Y. C.; Veloo, K. V.

2018-04-01

Reactive red 120 is used as a textile dye for fabric coloring. The dye waste is produced during textile finishing process subsequently released directly to water bodies which giving harmful effects to the environment due to the carcinogenic characteristic. Adsorption process becomes an effective treatment to treat textile dye. This research emphasizes the treatment of textile dye namely reactive red 120 (RR120) by using sugarcane bagasse powder. The batch study was carried out under varying parameters such as 60 minutes contact time, pH (1-8), dye concentration (5-25 mg/L), particle size (125-500 μm) and biosorbent dosage (0.01-0.2 g/L). The maximum adsorption percentage of RR120 was 94.62%. The adsorption of dye was increased with the decreasing of pH, initial dye concentration and particle size. Sugarcane bagasse powder as low-cost biosorbent was established using Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM). This locally agricultural waste could be upgraded into useful material which is biosorbent that promising for decolorization of colored textile wastewater.

Mycoremediation of congo red dye by filamentous fungi.

PubMed

Bhattacharya, Sourav; Das, Arijit; G, Mangai; K, Vignesh; J, Sangeetha

2011-10-01

Azo, anthroquinone and triphenylmethane dyes are the major classes of synthetic colourants, which are difficult to degrade and have received considerable attention. Congo red, a diazo dye, is considered as a xenobiotic compound, and is recalcitrant to biodegradative processes. Nevertheless, during the last few years it has been demonstrated that several fungi, under certain environmental conditions, are able to transfer azo dyes to non toxic products using laccases. The aim of this work was to study the factors influencing mycoremediation of Congo red. Several basidiomycetes and deuteromycetes species were tested for the decolourisation of Congo red (0.05 g/l) in a semi synthetic broth at static and shaking conditions. Poor decolourisation was observed when the dye acted as the sole source of nitrogen, whereas semi synthetic broth supplemented with fertilizer resulted in better decolourisation. Decolourisation of Congo red was checked in the presence of salts of heavy metals such as mercuric chloride, lead acetate and zinc sulphate. Decolourisation parameters such as temperature, pH, and rpm were optimized and the decolourisation obtained at optimized conditions varied between 29.25- 97.28% at static condition and 82.1- 100% at shaking condition. Sodium dodecyl sulphate polyacrylamide gel electrophoretic analysis revealed bands with molecular weights ranging between 66.5 to 71 kDa, a characteristic of the fungal laccases. High efficiency decolourisation of Congo red makes these fungal forms a promising choice in biological treatment of waste water containing Congo red.

Adsorption of the diazo dye Direct Red 23 onto a zinc oxide surface: A spectroscopic study

NASA Astrophysics Data System (ADS)

Lucilha, Adriana Campano; Bonancêa, Carlos Eduardo; Barreto, Wagner José; Takashima, Keiko

2010-01-01

The adsorption of the diazo dye Direct Red 23 onto a zinc oxide surface at 30 °C in the dark was investigated. The color reduction was monitored by spectrophotometry at 503 nm. The FTIR and Raman spectra of the Direct Red 23 adsorption as a function of ZnO concentration were registered. From the PM3 semi-empirical calculations of the atomic charge density and dipole moment of the Direct Red 23 molecule, it was demonstrated that the azo dye molecule may be adsorbed onto the ZnO surface through molecule geometry modifications, enhancing the interfacial area causing a variation in the bonding frequencies.

Molecular mechanism of tau aggregation induced by anionic and cationic dyes.

PubMed

Lira-De León, Karla I; García-Gutiérrez, Ponciano; Serratos, Iris N; Palomera-Cárdenas, Marianela; Figueroa-Corona, María Del P; Campos-Peña, Victoria; Meraz-Ríos, Marco A

2013-01-01

Abnormal tau filaments are a hallmark of Alzheimer's disease. Anionic dyes such as Congo Red, Thiazine Red, and Thioflavin S are able to induce tau fibrillization in vitro. SH-SY5Y cells were incubated with each dye for seven days leading to intracellular aggregates of tau protein, with different morphological characteristics. Interestingly, these tau aggregates were not observed when the Methylene Blue dye was added to the cell culture. In order to investigate the molecular mechanisms underlying this phenomenon, we developed a computational model for the interaction of the tau paired helical filament (PHF) core with every dye by docking analysis. The polar/electrostatic and nonpolar contribution to the free binding energy in the tau PHF core-anionic dye interaction was determined. We found that the tau PHF core can generate a positive net charge within the binding site localized at residuesLys311 and Lys340 (numbering according to the longest isoform hTau40). These residues are important for the binding affinity of the negative charges present in the anionic dyes causing an electrostatic environment that stabilizes the complex. Tau PHF core protofibril-Congo Red interaction has a stronger binding affinity compared to Thiazine Red or Thioflavin S. By contrast, the cationic dye Methylene Blue does not bind to nor stabilize the tau PHF core protofibrils. These results characterize the driving forces responsible for the binding of tau to anionic dyes leading to their self-aggregation and suggest that Methylene Blue may act as a destabilizing agent of tau aggregates.

Calcium Sensitive Fluorescent Dyes Fluo-4 and Fura Red under Pressure: Behaviour of Fluorescence and Buffer Properties under Hydrostatic Pressures up to 200 MPa

PubMed Central

Vass, H.; Reischl, B.; Allen, R. J.; Friedrich, O.

2016-01-01

The fluorescent Ca2+ sensitive dyes Fura Red (ratiometric) and Fluo-4 (non-ratiometric) are widely utilized for the optical assessment of Ca2+ fluctuations in vitro as well as in situ. The fluorescent behavior of these dyes is strongly depends on temperature, pH, ionic strength and pressure. It is crucial to understand the response of these dyes to pressure when applying calcium imaging technologies in the field of high pressure bioscience. Therefore, we use an optically accessible pressure vessel to pressurize physiological Ca2+-buffered solutions at different fixed concentrations of free Ca2+ (1 nM to 25.6 μM) and a specified dye concentration (12 μM) to pressures of 200 MPa, and record dye fluorescence intensity. Our results show that Fluo-4 fluorescence intensity is reduced by 31% per 100 MPa, the intensity of Fura Red is reduced by 10% per 100 MPa. The mean reaction volume for the dissociation of calcium from the dye molecules Δdv¯ is determined to -17.8 ml mol-1 for Fluo-4 and -21.3 ml mol-1 for Fura Red. Additionally, a model is presented that is used to correct for pressure-dependent changes in pH and binding affinity of Ca2+ to EGTA, as well as to determine the influence of these changes on dye fluorescence. PMID:27764134

The application of sensitizers from red frangipani flowers and star gooseberry leaves in dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Almaz Dhafina, Wan; Salleh, Hasiah; Zalani Daud, Muhamad; Ali, Nora’aini

2018-05-01

Nowadays natural based dyes for dye-sensitized solar cells (DSSCs) have been in research field attention due to its advantages over other type of dyes such as low-cost, low-toxicity, completely biodegradable and abundance of resources. Natural dyes can be produced via the simple extraction method of pigments from plant parts such as flower, fruits, leaves, tuber etc. In this feature article, the natural dyes which composed of anthocyanin pigment from red frangipani flowers and chlorophyll from star gooseberry leaves were applied in zinc oxide, (ZnO) based-DSSC. The ZnO photoanode of the DSSCs sample were sensitized in each dye with different duration. It was observed that DSSCs which has chlorophyll pigment as dye had better performance with power conversion efficiency (PCE) of 0.007%.

Why Congo red binding is specific for amyloid proteins - model studies and a computer analysis approach.

PubMed

Roterman, I; KrUl, M; Nowak, M; Konieczny, L; Rybarska, J; Stopa, B; Piekarska, B; Zemanek, G

2001-01-01

The complexing of Congo red in two different ligand forms - unimolecular and supramolecular (seven molecules in a micelle) - with eight deca-peptides organized in a b-sheet was tested by computational analysis to identify its dye-binding preferences. Polyphenylananine and polylysine peptides were selected to represent the specific side chain interactions expected to ensure particularly the stabilization of the dye-protein complex. Polyalanine was used to verify the participation of non-specific backbone-derived interactions. The initial complexes for calculation were constructed by intercalating the dye between the peptides in the middle of the beta-sheet. The long axis of the dye molecule (in the case of unimolecular systems) or the long axis of the ribbon-like micelle (in the case of the supramolecular dye form) was oriented parallel to the peptide backbone. This positioning maximally reduced the exposure of the hydrophobic diphenyl (central dye fragment) to water. In general the complexes of supramolecular Congo red ligands appeared more stable than those formed by individual dye molecules. Specific interactions (electrostatic and/or ring stacking) dominated as binding forces in the case of the single molecule, while non-specific surface adsorption seemed decisive in complexing with the supramolecular ligand. Both the unimolecular and supramolecular versions of the dye ligand were found to be likely to form complexes of sufficient stability with peptides. The low stability of the protein and the gap accessible to penetration in the peptide sheet seem sufficient for supramolecular ligand binding, but the presence of positively charged or hydrophobic amino acids may strengthen binding significantly. The need for specific interaction makes single-molecule Congo red binding rather unusual as a general amyloid protein ligand. The structural feature of Congo red, which enables specific and common interaction with amyloid proteins, probably derives from the ribbon-like self-assembled form of the dye.

Analyses of the genotoxic and mutagenic potential of the products formed after the biotransformation of the azo dye Disperse Red 1.

PubMed

Chequer, Farah Maria Drumond; Lizier, Thiago Mescoloto; de Felício, Rafael; Zanoni, Maria Valnice Boldrin; Debonsi, Hosana Maria; Lopes, Norberto Peporine; Marcos, Ricard; de Oliveira, Danielle Palma

2011-12-01

Azo dyes constitute the largest class of synthetic dyes. Following oral exposure, these dyes can be reduced to aromatic amines by the intestinal microflora or liver enzymes. This work identified the products formed after oxidation and reduction of the dye Disperse Red 1, simulating hepatic biotransformation and evaluated the mutagenic potential of the resultant solution. Controlled potential electrolysis was carried out on dye solution using a Potentiostat/Galvanostat. HPLC-DAD and GC/MS were used to determine the products generated after the oxidation/reduction process. The Salmonella/microsome assay with the strains TA98 and YG1041 without S9, and the mouse lymphoma assay (MLA) using the thymidine kinase (Tk) gene, were used to evaluate the mutagenicity of the products formed. Sulfate 2-[(4-aminophenyl)ethylamino]-ethanol monohydrate, nitrobenzene, 4-nitro-benzamine and 2-(ethylphenylamino)-ethanol were detected. This dye has already being assigned as mutagenic in different cell system. In addition, after the oxidation/reduction process the dye still had mutagenic activity for the Salmonella/microsome assay. Nevertheless, both the original dye Disperse Red 1 and its treated solutions showed negative results in the MLA. The present results suggest that the ingestion of water and food contaminated with this dye may represent human and environmental health problem, due to the generation of harmful compounds after biotransformation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Ultrasonically assisted hydrothermal synthesis of activated carbon-HKUST-1-MOF hybrid for efficient simultaneous ultrasound-assisted removal of ternary organic dyes and antibacterial investigation: Taguchi optimization.

PubMed

Azad, F Nasiri; Ghaedi, M; Dashtian, K; Hajati, S; Pezeshkpour, V

2016-07-01

Activated carbon (AC) composite with HKUST-1 metal organic framework (AC-HKUST-1 MOF) was prepared by ultrasonically assisted hydrothermal method and characterized by FTIR, SEM and XRD analysis and laterally was applied for the simultaneous ultrasound-assisted removal of crystal violet (CV), disulfine blue (DSB) and quinoline yellow (QY) dyes in their ternary solution. In addition, this material, was screened in vitro for their antibacterial actively against Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAO1) bacteria. In dyes removal process, the effects of important variables such as initial concentration of dyes, adsorbent mass, pH and sonication time on adsorption process optimized by Taguchi approach. Optimum values of 4, 0.02 g, 4 min, 10 mg L(-1) were obtained for pH, AC-HKUST-1 MOF mass, sonication time and the concentration of each dye, respectively. At the optimized condition, the removal percentages of CV, DSB and QY were found to be 99.76%, 91.10%, and 90.75%, respectively, with desirability of 0.989. Kinetics of adsorption processes follow pseudo-second-order model. The Langmuir model as best method with high applicability for representation of experimental data, while maximum mono layer adsorption capacity for CV, DSB and QY on AC-HKUST-1 estimated to be 133.33, 129.87 and 65.37 mg g(-1) which significantly were higher than HKUST-1 as sole material with Qm to equate 59.45, 57.14 and 38.80 mg g(-1), respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Cadmium telluride nanoparticles loaded on activated carbon as adsorbent for removal of sunset yellow

NASA Astrophysics Data System (ADS)

Ghaedi, M.; Hekmati Jah, A.; Khodadoust, S.; Sahraei, R.; Daneshfar, A.; Mihandoost, A.; Purkait, M. K.

2012-05-01

Adsorption is a promising technique for decolorization of effluents of textile dyeing industries but its application is limited due to requirement of high amounts of adsorbent required. The objective of this study was to assess the potential of cadmium telluride nanoparticles loaded onto activated carbon (CdTN-AC) for the removal of sunset yellow (SY) dye from aqueous solution. Adsorption studies were conducted in a batch mode varying solution pH, contact time, initial dye concentration, CdTN-AC dose, and temperature. In order to investigate the efficiency of SY adsorption on CdTN-AC, pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion kinetic models were studied. It was observed that the pseudo-second-order kinetic model fits better than other kinetic models with good correlation coefficient. Equilibrium data were fitted to the Langmuir model. Thermodynamic parameters such as enthalpy, entropy, activation energy, and sticking probability were also calculated. It was found that the sorption of SY onto CdTN-AC was spontaneous and endothermic in nature. The proposed adsorbent is applicable for SY removal from waste of real effluents including pea-shooter, orange drink and jelly banana with efficiency more than 97%.

Design of Far-Red Sensitizing Squaraine Dyes Aiming Towards the Fine Tuning of Dye Molecular Structure.

PubMed

Morimoto, Takuya; Fujikawa, Naotaka; Ogomi, Yuhei; Pandey, Shyam S; Ma, Tingli; Hayase, Shuzi

2016-04-01

Model squaraine dyes having sharp and narrow absorptions mainly in the far-red wavelength region has been logically designed, synthesized and used for their application as sensitizer in the dyesensitized solar cells (DSSC). In order to have fine control on energetics, dyes having same mother core and alkyl chain length varying only in molecular symmetry and position of substituent were designed. It has been found that even keeping all other structural factor constant, only positional variation of substituent leads to not only in the variation of energetics by 0.1 eV but affects the photovoltaic characteristics also. Optimum concentration of dye de-aggregating agent was found to be 100 times with respect to the sensitizing dye concentration. Amongst dyes utilized in this work best performance was obtained for unsymmetrical dye SQ-40 giving a photoconversion efficiency of 4.01% under simulated solar irradiation at global AM 1.5.

Influence of polar solvents on photovoltaic performance of Monascusred dye-sensitized solar cell

NASA Astrophysics Data System (ADS)

Lee, Jae Wook; Kim, Tae Young; Ko, Hyun Seok; Han, Shin; Lee, Suk-Ho; Park, Kyung Hee

Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (Jsc) of 1.23 mA/cm2, a photovoltage (Voc) of 0.75 V, and a fill factor of 0.72, corresponding to an energy conversion efficiency (η) of 0.66%.

Congo red dye affects survival and reproduction in the cladoceran Ceriodaphnia dubia. Effects of direct and dietary exposure.

PubMed

Hernández-Zamora, Miriam; Martínez-Jerónimo, Fernando; Cristiani-Urbina, Eliseo; Cañizares-Villanueva, Rosa Olivia

2016-12-01

Nearly 7 00000 tons of dyes are produced annually throughout the world. Azo dyes are widely used in the textile and paper industries due to their low cost and ease of application. Their extensive use results in large volumes of wastewater being discharged into aquatic ecosystems. Large volume discharges constitute a health risk since many of these dyes, such as Congo Red, are elaborated with benzidine, a known carcinogenic compound. Information regarding dye toxicity in aquatic ecosystems is limited. Therefore, the aim of the present study was to evaluate the effect of Congo Red on survival and reproduction of Ceriodaphnia dubia. We determined the 48 h median lethal concentration (LC 50 ) and evaluated the effects of sublethal concentrations in subchronic exposures by using as food either fresh algae or algae previously exposed to the dye. LC 50 was 13.58 mg L -1 . In subchronic assays, survival was reduced to 80 and 55 %, and fertility to 40 and 70 %, as compared to the control, in C. dubia fed with intoxicated cells or with the mix of intoxicated + fresh algae, respectively, so the quantity and type of food had a significant effect. We determined that Congo Red is highly toxic to C. dubia since it inhibits survival and fertility in concentrations exceeding 3 mg L -1 . Our results show that this dye produces negative effects at very low concentrations. Furthermore, our findings warn of the risk associated with discharging dyes into aquatic environments. Lastly, the results emphasize the need to regulate the discharge of effluents containing azo dyes.

Identification of natural red and purple dyes on textiles by Fiber-optics Reflectance Spectroscopy

NASA Astrophysics Data System (ADS)

Maynez-Rojas, M. A.; Casanova-González, E.; Ruvalcaba-Sil, J. L.

2017-05-01

Understanding dye chemistry and dye processes is an important issue for studies of cultural heritage collections and science conservation. Fiber Optics Reflectance Spectroscopy (FORS) is a powerful technique, which allows preliminary dye identification, causing no damage or mechanical stress on the artworks subjected to analysis. Some information related to specific light scattering and absorption can be obtained in the UV-visible and infrared range (300-1400 nm) and it is possible to discriminate the kind of support fiber in the near infrared region (1000-2500 nm). The main spectral features of natural dye fibers samples, such as reflection maxima, inflection points and reflection minima, can be used in the differentiation of various red natural dyes. In this work, a set of dyed references were manufactured following Mexican recipes with red dyes (cochineal and brazilwood) in order to determine the characteristic FORS spectral features of fresh and aged dyed fibers for their identification in historical pieces. Based on these results, twenty-nine indigenous textiles belonging to the National Commission for the Development of Indigenous People of Mexico were studied. Cochineal and brazilwood were successfully identified by FORS in several pieces, as well as the mixture of cochineal and indigo for purple color.

Synthesis and spectroscopic properties of silica-dye-semiconductor nanocrystal hybrid particles.

PubMed

Ren, Ting; Erker, Wolfgang; Basché, Thomas; Schärtl, Wolfgang

2010-12-07

We prepared silica-dye-nanocrystal hybrid particles and studied the energy transfer from semiconductor nanocrystals (= donor) to organic dye molecules (= acceptor). Multishell CdSe/CdS/ZnS semiconductor nanocrystals were adsorbed onto monodisperse Stöber silica particles with an outer silica shell of thickness 2-23 nm containing organic dye molecules (Texas Red). The thickness of this dye layer has a strong effect on the energy transfer efficiency, which is explained by the increase in the number of dye molecules homogeneously distributed within the silica shell, in combination with an enhanced surface adsorption of nanocrystals with increasing dye amount. Our conclusions were underlined by comparison of the experimental results with numerically calculated FRET efficiencies and by control experiments confirming attractive interaction between the nanocrystals and Texas Red freely dissolved in solution.

Photoelectric characterization of fabricated dye-sensitized solar cell using dye extracted from red Siahkooti fruit as natural sensitizer

NASA Astrophysics Data System (ADS)

Mozaffari, Sayed Ahmad; Saeidi, Mahsa; Rahmanian, Reza

2015-05-01

Natural dye extracted from Siahkooti fruit with/without purification by solid phase extraction (SPE) technique was used in the fabrication of DSSC as natural sensitizer. The UV-Vis absorption spectroscopy and Fourier transform infrared (FTIR) were employed to indicate the presence of anthocyanins in the fruit of red Siahkooti. The photoelectrochemical performance and the efficiency of assembled DSSC using Siahkooti fruit dye extract were evaluated and efficiency enhancement was obtained by a preliminary purification of extracted dye. The efficiency and fill factor of the DSSC using purified Siahkooti fruit dye were 0.32% and 0.73%, respectively. The results successfully showed that the DSSC, using Siahkooti fruit extract as a dye sensitizer, is useful for the preparation of environmentally friendly, low-cost, renewable and clean sources of energy.

Adsorption of Congo red dye onto antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels.

PubMed

El-Harby, Nouf F; Ibrahim, Shaimaa M A; Mohamed, Nadia A

2017-11-01

Adsorption capacity of three antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels for Congo red dye removal from its aqueous solution has been investigated for the first time in this work. These hydrogels were prepared by reacting chitosan with various amounts of terephthaloyl diisothiocyanate cross-linker. The effect of the hydrogel structural variations and several dye adsorption processing parameters to achieve the best adsorption capacity were investigated. The hydrogels' structural variations were obtained by varying their terephthaloyl thiourea moieties content. The processing variables included initial concentration of the dye solution, temperature and time of exposure to the dye. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by the pseudo-second-order equation and the Langmuir equation, respectively. On the basis of the Langmuir analysis Congo red dye gave the maximum sorption capacity of 44.248 mg/g. The results obtained confirmed that the sorption phenomena are most likely to be controlled by chemisorption process. The adsorption reaction was endothermic and spontaneous according to the calculated results of adsorption thermodynamics.

Effects of a Red Marker Dye on Aedes and Culex Larvae: Are There Implications for Operational Mosquito Control?

PubMed

Unlu, Isik; Leisnham, Paul T; Williams, Gregory M; Klingler, Kim; Dow, Garrett W; Kirchoff, Nicole; Jin, Sophie; Delisi, Nicholas; Montenegro, Katherine; Faraji, Ary

2015-12-01

Marker dyes are often mixed with liquid insecticide formulations prior to field applications to accurately determine the characteristics and penetration of droplets into targeted habitats. We have been using FD&C Red 40 Granular DM food dye at the rate of 20 g/liter in liquid solutions of Bacillus thuringiensis israelensis (Bti) for area-wide larvicide applications against the Asian tiger mosquito, Aedes albopictus. The Bti and dye mix ratio has been recommended by pesticide manufacturers for testing under operational conditions, but no data exist on the effects of the dye itself on mosquito larvae. We tested the effects of the FD&C Red 40 food dye in laboratory bioassays against different strains of Ae. albopictus (New Jersey and Maryland) and Culex pipiens pipiens (Utah) at rates of 0.039 to 80.0 g/liter. We also conducted field application trials to measure dye concentrations up to 100 m downwind when mixed and applied according to manufacturer instructions. In laboratory bioassays, we found that mean survival in cups with dye were significantly different from the controls beginning at 10.0 g/liter for New Jersey Ae. albopictus and at 20.0 g/liter for Maryland Ae. albopictus and Utah Cx. p. pipiens. In field application trials, we recorded a maximum volume density of 1,152.8 nl/cm(2) and calculated the maximum concentration of dye at 9.09 × 10(-3) g/liter. Our results showed that although we detected greater effects of dye on Ae. albopictus in New Jersey experiments than Ae. albopictus in Maryland and Cx. p. pipiens from Utah, concentrations of the dye during operational applications were at least 1,100 times below concentrations that exhibited toxic effects for either species in the laboratory, suggesting that the dye will not interfere with accuracy of field bioassays. Our results conclusively demonstrate that the addition of the FD&C Red 40 marker dye does not alter the efficacy of the pesticide formulation by skewing results, but rather provides a valuable addition to accurately determine pesticide penetration and spectrum by discriminating between intended pesticide and other potential pollutants.

Dye-sensitized solar cells using natural dyes as sensitizers from Malaysia local fruit `Buah Mertajam'

NASA Astrophysics Data System (ADS)

Hambali, N. A. M. Ahmad; Roshidah, N.; Hashim, M. Norhafiz; Mohamad, I. S.; Saad, N. Hidayah; Norizan, M. N.

2015-05-01

We experimentally demonstrate the high conversion efficiency, low cost, green technology and easy to fabricate dye-sensitized solar cells (DSSCs) using natural anthocyanin dyes as sensitizers. The DSSCs was fabricated by using natural anthocyanin dyes which were extracted from different parts of the plants inclusive `Buah Mertajam', `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. The natural anthocyanin dyes that found in flower, leaves and fruits were extracted by the simple procedures. This anthocyanin dye is used to replace the expensive chemical synthetic dyes due to its ability to effectively attach into the surface of Titanium dioxide (TiO2). A natural anthocyanin dyes molecule adsorbs to each particle of the TiO2 and acts as the absorber of the visible light. A natural anthocyanin dye from Buah Mertajam shows the best performance with the conversion efficiency of 5.948% and fill factor of 0.708 followed by natural anthocyanin dyes from `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. Buah Mertajam or scientifically known as eriglossum rubiginosum is a local Malaysia fruit.

Adsorption Properties of p -Methyl Red Monomeric-to-Pentameric Dye Aggregates on Anatase (101) Titania Surfaces: First-Principles Calculations of Dye/TiO 2 Photoanode Interfaces for Dye-Sensitized Solar Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Lei; Cole, Jacqueline M.

2014-08-29

The optical and electronic properties of dye aggregates of p-methyl red on a TiO2 anatase (101) surface were modeled as a function of aggregation order (monomer to pentameric dye) via first principles calculations. A progressive red-shifting and intensity increase toward the visible region in UV/vis absorption spectra is observed from monomeric-to-tetrameric dyes, with each molecule in a given aggregate binding to one of the four possible TiO2 (101) adsorption sites. The pentamer exhibits a blue-shifted peak wave- length in the UV/vis absorption spectra and less absorption intensity in the visible region in comparison; a corresponding manifestation of H-aggregation occurs sincemore » one of these five molecules cannot occupy an adsorption site. This finding is consistent with experiment. Calculated density of states (DOS) and partial DOS spectra reveal similar dye…TiO2 nanocomposite conduction band characteristics but different valence band features. Associated molecular orbital distributions reveal dye-to-TiO2 interfacial charge transfer in all five differing aggregate orders; meanwhile, the level of intramolecular charge transfer in the dye becomes progressively localized around its azo- and electron-donating groups, up to the tetrameric dye/TiO2 species. Dye adsorption energies and dye coverage levels are calculated and compared with experiment. Overall, the findings of this case study serve to aid the molecular design of azo dyes towards better performing DSSC devices wherein they are incorporated. In addition, they provide a helpful example reference for understanding the effects of dye aggregation on the adsorbate…TiO2 interfacial optical and electronic properties.« less

Photophysical investigations of squaraine and cyanine dyes and their interaction with bovine serum albumin

NASA Astrophysics Data System (ADS)

Saikiran, M.; Sato, D.; Pandey, S. S.; Kato, T.

2016-04-01

A model far-red sensitive symmetrical squaraine dye (SQ-3) and unsymmetrical near infra-red sensitive cyanine dye (UCD-1) bearing direct-COOH functionalized indole ring were synthesized, characterized and subjected to photophysical investigations including their interaction with bovine serum albumin (BSA) as a model protein in phosphate buffer solution (PBS). Both of the dyes exhibit strong interaction with BSA in phosphate buffer with high apparent binding constant. A judicious tuning of hydrophobic main backbone with reactive functionality for associative interaction with active site of BSA has been found to be necessary for BSA detection in PBS.

Variations in thermo-optical properties of neutral red dye with laser ablated gold nanoparticles

NASA Astrophysics Data System (ADS)

Prakash, Anitha; Pathrose, Bini P.; Mathew, S.; Nampoori, V. P. N.; Radhakrishnan, P.; Mujeeb, A.

2018-05-01

We have investigated the thermal and optical properties of neutral red dye incorporated with different weight percentage of gold nanoparticles prepared by laser ablation method. Optical absorption studies confirmed the production of spherical nanoparticles and also the interactions of the dye molecules with gold nanoparticles. The quenching of fluorescence and the reduction in the lifetime of gold incorporated samples were observed and was due to the non-radiative energy transfer between the dye molecules and gold nanoparticles. Dual beam thermal lens technique has been employed to measure the heat diffusion in neutral red with various weight percentage of gold nano sol dispersed in ethanol. The significant outcome of the experiment is that, the overall heat diffusion is slower in the presence of gold nano sol compared to that of dye alone sample. Brownian motion is suggested to be the main mechanism of heat transfer under the present conditions. The thermal diffusivity variations of samples with respect to different excitation power of laser were also studied.

Decolorization of Congo Red by Phanerochaete chrysosporium: the role of biosorption and biodegradation.

PubMed

Bosco, Francesca; Mollea, Chiara; Ruggeri, Bernardo

2017-10-01

The degradation of Congo Red by means of Phanerochaete chrysosporium BKM-F-1767 is reported in this work. Solid and liquid cultures have been prepared to evaluate in vivo biodegradation as well as the role of biosorption phenomena on mycelium. Moreover, in vitro tests have been performed to define the influence of MnP on dye decolorization. P. chrysosporium, cultivated on Malt Extract Agar in the presence of Congo Red 0.005% (w/v), has shown good growth and the ability to decolorize the dye in the 25-39°C temperature range. It has also been cultivated in a low NMM liquid medium with the aforementioned dye concentration in immobilized stationary cultures inducted for Lignin Peroxidase (LiP) and Manganese Peroxidase (MnP) production. Congo Red was absorbed on the biomass and then decolorized (93% and 85% for the LiP and MnP cultures, respectively). The cultures with added Congo Red have shown a higher MnP synthesis rate than a control without the dye. The enzymatic degradation of Congo Red has also been investigated by means of the extracellular fluid for different MnP activities (0-300 IU/l); the decolorization percentage has been found to be clearly related to the enzyme concentration up to a value of about 200 IU/l.

Influence of polar solvents on photovoltaic performance of Monascusred dye-sensitized solar cell.

PubMed

Lee, Jae Wook; Kim, Tae Young; Ko, Hyun Seok; Han, Shin; Lee, Suk-Ho; Park, Kyung Hee

2014-05-21

Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (Jsc) of 1.23mA/cm(2), a photovoltage (Voc) of 0.75V, and a fill factor of 0.72, corresponding to an energy conversion efficiency (η) of 0.66%. Copyright © 2014 Elsevier B.V. All rights reserved.

Mechanism of triphenylmethane Cresol Red degradation by Trichoderma harzianum M06.

PubMed

Nor, Nurafifah Mohd; Hadibarata, Tony; Zubir, Meor Mohd Fikri Ahmad; Lazim, Zainab Mat; Adnan, Liyana Amalina; Fulazzaky, Mohamad Ali

2015-11-01

Cresol Red belongs to the triphenylmethane (TPM) class of dyes which are potentially carcinogenic or mutagenic. However, very few studies on biodegradation of Cresol Red were investigated as compared to other type dyes such as azo and anthraquinone dye. The aim of this work is to evaluate triphenylmethane dye Cresol Red degradation by fungal strain isolated from the decayed wood in Johor Bahru, Malaysia. Detailed taxonomic studies identified the organisms as Trichoderma species and designated as strain Trichoderma harzianum M06. In this study, Cresol Red was decolorized up to 88% within 30 days under agitation condition by Trichoderma harzianum M06. Data analysis revealed that a pH value of 3 yielded a highest degradation rate among pH concentrations (73%), salinity concentrations of 100 g/L (73%), and a volume of 0.1 mL of Tween 80 (79%). Induction in the enzyme activities of manganese peroxidase, lignin peroxidase, laccase, 1,2- and 2,3-dioxygenase indicates their involvement in Cresol Red removal. Various analytical studies such as Thin-Layer Chromatography (TLC), UV-Vis spectrophotometer, and Gas chromatography mass spectrometry (GC-MS) confirmed the biotransformation of Cresol Red by the fungus. Two metabolites were identified in the treated medium: 2,4-dihydroxybenzoic acid (t R 7.3 min and m/z 355) and 2-hydroxybenzoic acid (t R 8.6 min and m/z 267). Based on these products, a probable pathway has been proposed for the degradation of Cresol Red by Trichoderma harzianum M06.

Concept Evaluation of Visual Cleaning Performance Indicators (VCPI) for Real Time Cleaning Verification

DTIC Science & Technology

2002-03-15

Dyes Used § ORO § Food Green 3 § Alizarin § Natural Red 4 (Carminic Acid) § ORO § FG3 § ALZ § NR4 (or CAR) Panel Materials § Al2024...with Natural Red 4 (NR4) dye . Blank panels were not contaminated or labeled. The following protocol based on T.O.1-1-691 was used to clean the...Preliminary Estimate of Dye Use Level Required for the VCPI Technique ................................................................................30

Photoelectric characterization of fabricated dye-sensitized solar cell using dye extracted from red Siahkooti fruit as natural sensitizer.

PubMed

Mozaffari, Sayed Ahmad; Saeidi, Mahsa; Rahmanian, Reza

2015-05-05

Natural dye extracted from Siahkooti fruit with/without purification by solid phase extraction (SPE) technique was used in the fabrication of DSSC as natural sensitizer. The UV-Vis absorption spectroscopy and Fourier transform infrared (FTIR) were employed to indicate the presence of anthocyanins in the fruit of red Siahkooti. The photoelectrochemical performance and the efficiency of assembled DSSC using Siahkooti fruit dye extract were evaluated and efficiency enhancement was obtained by a preliminary purification of extracted dye. The efficiency and fill factor of the DSSC using purified Siahkooti fruit dye were 0.32% and 0.73%, respectively. The results successfully showed that the DSSC, using Siahkooti fruit extract as a dye sensitizer, is useful for the preparation of environmentally friendly, low-cost, renewable and clean sources of energy. Copyright © 2015 Elsevier B.V. All rights reserved.

Curcumin as an amyloid-indicator dye in E. coli.

PubMed

McCrate, Oscar A; Zhou, Xiaoxue; Cegelski, Lynette

2013-05-14

We have demonstrated that curcumin is an amyloid-specific dye in E. coli. Curcumin binds to curliated whole cells and to isolated curli amyloid fibers. Similar to Congo red, curcumin exhibits a red-shift in absorbance and a significant increase in fluorescence upon binding to isolated curli.

Curcumin as an Amyloid-indicator Dye in E. coli †

PubMed Central

McCrate, Oscar A.; Zhou, Xiaoxue; Cegelski, Lynette

2013-01-01

We have demonstrated that curcumin is an amyloid-specific dye in E. coli. Curcumin binds to curliated whole cells and to isolated curli amyloid fibers. Similar to Congo red, curcumin exhibits a red-shift in absorbance and a significant increase in fluorescence upon binding to isolated curli. PMID:23287899

Photocatalytic degradation and photo-Fenton oxidation of Congo red dye pollutants in water using natural chromite—response surface optimization

NASA Astrophysics Data System (ADS)

Shaban, Mohamed; Abukhadra, Mostafa R.; Ibrahim, Suzan S.; Shahien, Mohamed. G.

2017-12-01

Refined natural Fe-chromite was characterized by XRD, FT-IR, reflected polarized microscope, XRF and UV spectrophotometer. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye by Fe-chromite was investigated using 1 mL H2O2. The degradation of dye was studied as a function of illumination time, chromite mass, initial dye concentration, and pH. Fe-chromite acts as binary oxide system from chromium oxide and ferrous oxide. Thus, it exhibits photocatalytic properties under UV illumination and photo-Fenton oxidation after addition of H2O2. The degradation in the presence of H2O2 reached the equilibrium stage after 8 h (59.4%) but in the absence of H2O2 continued to 12 h (54.6%). Photocatalytic degradation results fitted well with zero, first order and second order kinetic model but it represented by second order rather than by the other models. While the photo-Fenton oxidation show medium fitting with the second order kinetic model only. The values of kinetic rate constants for the photo-Fenton oxidation were greater than those for the photocatalytic degradation. Thus, degradation of Congo red dye using chromite as catalyst is more efficient by photo-Fenton oxidation. Based on the response surface analysis, the predicted optimal conditions for maximum removal of Congo red dye by photocatalytic degradation (100%) were 12 mg/l, 0.14 g, 3, and 11 h for dye concentration, chromite mass, pH, and illumination time, respectively. Moreover, the optimum condition for photo-Fenton oxidation of dye (100%) is 13.5 mg/l, 0.10 g, 4, and 10 h, respectively.

Decolorization and mineralization of Allura Red AC aqueous solutions by electrochemical advanced oxidation processes.

PubMed

Thiam, Abdoulaye; Sirés, Ignasi; Garrido, José A; Rodríguez, Rosa M; Brillas, Enric

2015-06-15

The decolorization and mineralization of solutions containing 230 mg L(-1) of the food azo dye Allura Red AC at pH 3.0 have been studied upon treatment by electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with a stirred tank reactor containing a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode to generate H2O2. The main oxidants were hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between H2O2 and added Fe(2+). The oxidation ability increased in the sequence EO-H2O2 < EF < PEF and faster degradation was always obtained using BDD. PEF process with BDD yielded almost total mineralization following similar trends in SO4(2-), ClO4(-) and NO3(-) media, whereas in Cl(-) medium, mineralization was inhibited by the formation of recalcitrant chloroderivatives. GC-MS analysis confirmed the cleavage of the −N=N− bond with formation of two main aromatics in SO4(2-) medium and three chloroaromatics in Cl(-) solutions. The effective oxidation of final oxalic and oxamic acids by BDD along with the photolysis of Fe(III)-oxalate species by UVA light accounted for the superiority of PEF with BDD. NH4(+), NO3(-) and SO4(2-) ions were released during the mineralization. Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of natural red and purple dyes on textiles by Fiber-optics Reflectance Spectroscopy.

PubMed

Maynez-Rojas, M A; Casanova-González, E; Ruvalcaba-Sil, J L

2017-05-05

Understanding dye chemistry and dye processes is an important issue for studies of cultural heritage collections and science conservation. Fiber Optics Reflectance Spectroscopy (FORS) is a powerful technique, which allows preliminary dye identification, causing no damage or mechanical stress on the artworks subjected to analysis. Some information related to specific light scattering and absorption can be obtained in the UV-visible and infrared range (300-1400nm) and it is possible to discriminate the kind of support fiber in the near infrared region (1000-2500nm). The main spectral features of natural dye fibers samples, such as reflection maxima, inflection points and reflection minima, can be used in the differentiation of various red natural dyes. In this work, a set of dyed references were manufactured following Mexican recipes with red dyes (cochineal and brazilwood) in order to determine the characteristic FORS spectral features of fresh and aged dyed fibers for their identification in historical pieces. Based on these results, twenty-nine indigenous textiles belonging to the National Commission for the Development of Indigenous People of Mexico were studied. Cochineal and brazilwood were successfully identified by FORS in several pieces, as well as the mixture of cochineal and indigo for purple color. Copyright © 2017 Elsevier B.V. All rights reserved.

Immobilized laccase mediated dye decolorization and transformation pathway of azo dye acid red 27.

PubMed

Chhabra, Meenu; Mishra, Saroj; Sreekrishnan, Trichur Ramaswamy

2015-01-01

Laccases have good potential as bioremediating agents and can be used continuously in the immobilized form like many other enzymes. In the present study, laccase from Cyathus bulleri was immobilized by entrapment in Poly Vinyl Alcohol (PVA) beads cross-linked with either nitrate or boric acid. Immobilized laccase was used for dye decolorization in both batch and continuous mode employing a packed bed column. The products of degradation of dye Acid Red 27 were identified by LC MS/MS analysis. The method led to very effective (90%) laccase immobilization and also imparted significant stability to the enzyme (more than 70% after 5 months of storage at 4°C). In batch decolorization, 90-95% decolorization was achieved of the simulated dye effluent for up to 10-20 cycles. Continuous decolorization in a packed bed bioreactor led to nearly 90% decolorization for up to 5 days. The immobilized laccase was also effective in decolorization and degradation of Acid Red 27 in the presence of a mediator. Four products of degradation were identified by LC-MS/MS analysis. The immobilized laccase in PVA-nitrate was concluded to be an effective agent in treatment of textile dye effluents.

Fluorescent measurements in whole blood and plasma using red-emitting dyes

NASA Astrophysics Data System (ADS)

Abugo, Omoefe O.; Herman, Petr; Lakowicz, Joseph R.

2000-04-01

We have determined the fluorescence characteristics of albumin blue 670 and Rhodamine 800 in plasma and blood in order to test the feasibility of making direct fluorescence sensing measurements in blood. These dyes were used because of their absorption in the red/NIR where absorption by hemoglobin is minimized. Front face illumination and detection was used to minimize absorption and scattering during measurement. Fluorescence emission was observed for these dyes in plasma and blood. Attenuation of the fluorescence emission was observed in blood because of hemoglobin absorption. Using frequency domain fluorometry, we recovered the expected lifetime parameters for both dyes in blood and plasma. We were able to quantify HSA concentrations using changes in the mean lifetime of AB670, a dye previously shown to bind preferentially to HSA. Rh800 concentrations in plasma and blood were also determined using modulation sensing. Anisotropy measurements revealed high Anisotropy for these dyes in plasma and blood. It also showed an increase in the anisotropy of AB670 with increase in HSA concentration in the presence of red blood cells. These results indicate that qualitative and quantitative fluorescence measurements can be made directly in blood without the need to process the blood.

Evidence for significantly enhancing reduction of Azo dyes in Escherichia coli by expressed cytoplasmic Azoreductase (AzoA) of Enterococcus faecalis.

PubMed

Feng, J; Heinze, T M; Xu, H; Cerniglia, C E; Chen, H

2010-05-01

Although cytoplasmic azoreductases have been purified and characterized from various bacteria, little evidence demonstrating that these azoreductases are directly involved in azo dye reduction in vivo is known. In order to evaluate the contribution of the enzyme to azo dye reduction in vivo, experiments were conducted to determine the effect of a recombinant cytoplasmic azoreductase (AzoA) from Enterococcus faecalis expressed in Escherichia coli on the rate of metabolism of Methyl Red, Ponceau BS and Orange II. The intact cells that contained IPTG induced AzoA had a higher rate of dye reduction with increases of 2 (Methyl Red), 4 (Ponceau BS) and 2.6 (Orange II)-fold compared to noninduced cells, respectively. Metabolites of Methyl Red isolated from induced cultures were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid through liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) analyses. In conclusion, our data demonstrate that AzoA from Ent. faecalis is capable of increasing the reduction of azo dyes in intact E. coli cells and that cytoplasmic azoreductase is involved in bacterial dye degradation in vivo.

Evidence for Significantly Enhancing Reduction of Azo Dyes in Escherichia coli by Expressed Cytoplasmic Azoreductase (AzoA) of Enterococcus faecalis

PubMed Central

Feng, Jinhui; Heinze, Thomas M.; Xu, Haiyan; Cerniglia, Carl E.; Chen, Huizhong

2018-01-01

Although cytoplasmic azoreductases have been purified and characterized from various bacteria, little evidence demonstrating that these azoreductases are directly involved in azo dye reduction in vivo is known. In order to evaluate the contribution of the enzyme to azo dye reduction in vivo, experiments were conducted to determine the effect of a recombinant cytoplasmic azoreductase (AzoA) from Enterococcus faecalis expressed in Escherichia coli on the rate of metabolism of Methyl Red, Ponceau BS and Orange II. The intact cells that contained IPTG induced AzoA had a higher rate of dye reduction with increases of 2 (Methyl Red), 4 (Ponceau BS) and 2.6 (Orange II)-fold compared to noninduced cells, respectively. Metabolites of Methyl Red isolated from induced cultures were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid through liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) analyses. In conclusion, our data demonstrate that AzoA from Ent. faecalis is capable of increasing the reduction of azo dyes in intact E. coli cells and that cytoplasmic azoreductase is involved in bacterial dye degradation in vivo. PMID:19663804

Gamma irradiation and steam pretreatment of jute stick powder for the enhancement of dye adsorption efficiency

NASA Astrophysics Data System (ADS)

Parvin, Fahmida; Sultana, Nargis; Habib, S. M. Ahsan; Bhoumik, Nikhil Chandra

2017-11-01

The aim of this study is to find out the facile and effective pretreatment technique to enhance the capacity of jute stick powder (JSP) in adsorbing dye from raw textile effluent. Hence, different pretreatment techniques, i.e., radiation treatment, alkali treatment, ammonia treatment, steam treatment and CaCl2 treatment were applied to JSP and the adsorbing performance were examined for synthetic dye solutions (Blue FCL and Red RL dye). Different gamma radiation doses were applied on JSP and optimum dye removal efficiency was found at 500 krad in removing these two dyes (50 ppm) from solutions. Among the different pretreatment techniques, gamma irradiated JSP (500 Krad) exhibits highest dye uptake capacity for RED RL dye, whereas steam-treated JSP shows highest performance in adsorbing blue FCL dye. Subsequently, we applied the gamma irradiated and steam-treated JSP on real textile effluent (RTE) and these two techniques shows potentiality in adsorbing dye from raw textile effluent and in reducing BOD5, COD load and TOC to some extent as well. Fourier transform infrared spectroscopy (FTIR) analysis also proved that dye has been adsorbed on pretreated JSP.

Media composition and incubation temperature affect Congo red dye affinity of Shiga toxin-producing Escherichia coli

USDA-ARS?s Scientific Manuscript database

Background: Escherichia coli biofilm formation is dependent on curli fimbriae and cellulose, and the expression of both varies among Shiga toxin-producing E. coli (STEC). Curli and cellulose expression are often identified by their affinity for Congo red dye (CR) but media composition and incubation...

Accelerated decolorization of azo dye Congo red in a combined bioanode-biocathode bioelectrochemical system with modified electrodes deployment.

PubMed

Kong, Fanying; Wang, Aijie; Cheng, Haoyi; Liang, Bin

2014-01-01

In this study, BES with bioanode and biocathode was applied to decolorize an azo dye Congo red (CR). Results showed that the Congo red decolorization efficiency (CR-DE) within 23 h in a combined bioanode-biocathode single chamber BES was 98.3±1.3%, significantly higher than that of mixed solution in a dual chamber BES (67.2±3.5%) (P<0.005). Various electrodes deployments (horizontal, vertical and surrounding) in the combined bioanode-biocathode BES were further compared based on the decolorization performance and electrochemical characterization. Results indicated that CR-DE within 11h improved from 87.4±1.3% to 97.5±2.3%, meanwhile the internal resistance decreased from 236.6 to 42.2Ω as modifying the horizontal deployment to be a surrounding deployment. It proved that the combination of bioanode and biocathode with suitable electrodes deployment could accelerate the decolorization of azo dye Congo red, which would be great potential for the application of bioelectrochemical technology in azo dye wastewater treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dyed in the Wool.

ERIC Educational Resources Information Center

Kinsey, Lori Jean

1984-01-01

Procedures for dying and mordanting wool fibers and for preparing dyes from red onion skin, purple cabbage, pine needles, and purple lilac are presented. Information on the history of dyes and on how dyes work is included. (JN)

Protein determination by microchip capillary electrophoresis using an asymmetric squarylium dye: noncovalent labeling and nonequilibrium measurement of association constants.

PubMed

Sloat, Amy L; Roper, Michael G; Lin, Xiuli; Ferrance, Jerome P; Landers, James P; Colyer, Christa L

2008-08-01

In response to a growing interest in the use of smaller, faster microchip (mu-chip) methods for the separation of proteins, advancements are proposed that employ the asymmetric squarylium dye Red-1c as a noncovalent label in mu-chip CE separations. This work compares on-column and precolumn labeling methods for the proteins BSA, beta-lactoglobulin B (beta-LB), and alpha-lactalbumin (alpha-LA). Nonequilibrium CE of equilibrium mixtures (NECEEM) represents an efficient method to determine equilibrium parameters associated with the formation of intermolecular complexes, such as those formed between the dye and proteins in this work, and it allows for the use of weak affinity probes in protein quantitation. In particular, nonequilibrium methods employing both mu-chip and conventional CE systems were implemented to determine association constants governing the formation of noncovalent complexes of the red luminescent squarylium dye Red-1c with BSA and beta-LB. By our mu-chip NECEEM method, the association constants K(assoc) for beta-LB and BSA complexes with Red-1c were found to be 3.53 x 10(3) and 1.65 x 10(5) M(-1), respectively, whereas association constants found by our conventional CE-LIF NECEEM method for these same protein-dye systems were some ten times higher. Despite discrepancies between the two methods, both confirmed the preferential interaction of Red-1c with BSA. In addition, the effect of protein concentration on measured association constant was assessed by conventional CE methods. Although a small decrease in K(assoc) was observed with the increase in protein concentration, our studies indicate that absolute protein concentration may affect the equilibrium determination less than the relative concentration of protein-to-dye.

Adsorption of C.I. Reactive Red 228 and Congo Red dye from aqueous solution by amino-functionalized Fe3O4 particles: kinetics, equilibrium, and thermodynamics.

PubMed

Yan, Ting-guo; Wang, Li-Juan

2014-01-01

A magnetic adsorbent was synthesized by γ-aminopropyltriethoxysilane (APTES) modification of Fe(3)O(4) particles using a two-step process. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and vibration sample magnetometry were used to characterize the obtained magnetic adsorbent. EDS and XPS showed that APTES polymer was successfully introduced onto the as-prepared Fe(3)O(4)/APTES particle surfaces. The saturation magnetization of the magnetic adsorbent was around 65 emu g(-1), which indicated that the dye can be removed fast and efficiently from aqueous solution with an external magnetic field. The maximum adsorption capacities of Fe(3)O(4)/APTES for C.I. Reactive Red 228 (RR 228) and Congo Red (CR) were 51.4 and 118.8 mg g(-1), respectively. The adsorption of C.I. Reactive Red 228 (RR 228) and Congo Red (CR) on Fe(3)O(4)/APTES particles corresponded well to the Langmuir model and the Freundlich model, respectively. The adsorption processes for RR 228 and CR followed the pseudo-second-order model. The Boyd's film-diffusion model showed that film diffusion also played a major role in the studied adsorption processes for both dyes. Thermodynamic study indicated that both of the adsorption processes of the two dyes are spontaneous exothermic.

Color and COD degradation in photocatalytic process of procion red by using TiO2 catalyst under solar irradiation

NASA Astrophysics Data System (ADS)

Sari, Melati Ireng; Agustina, Tuty Emilia; Melwita, Elda; Aprianti, Tine

2017-11-01

Increasing textile industries in Indonesia resulted in increasing the utilization of dyes. The use of synthetic dyes are still dominating because they have many advantages. But, synthetic dyes are difficult to decompose in nature so they can cause potential pollution if discharged directly into the environment. In this study, Procion Red was used as a model of synthetic dye wastewater. The objective of this research is to study the effect of TiO2 catalyst concentration and irradiation time on the degradation of Procion Red under solar irradiation. Photo degradation takes place by using TiO2 catalyst powder in the various concentration of Procion Red of 150-300 ppm. The various concentrations of TiO2 catalyst of 0.5-8 g/l were used. The color and COD degradation of Procion Red for 12 hours of solar irradiation were investigated. Color degradation was measured by using a spectrophotometer. While COD degradation was measured by using Ferrous Ammonium Sulfate (FAS) analysis method. The result showed when using Procion Red of 150 ppm, the highest color degradation of 100% was achieved by using TiO2 catalyst of 6 g/l and the highest COD degradation of 62% was obtained by using TiO2 catalyst of 8 g/l, under 12 hours of solar irradiation

Comparison of activated carbon and iron/cerium modified activated carbon to remove methylene blue from wastewater.

PubMed

Cheng, Song; Zhang, Libo; Ma, Aiyuan; Xia, Hongying; Peng, Jinhui; Li, Chunyang; Shu, Jianhua

2018-03-01

The methylene blue (MB) removal abilities of raw activated carbon and iron/cerium modified raw activated carbon (Fe-Ce-AC) by adsorption were researched and compared. The characteristics of Fe-Ce-AC were examined by N 2 adsorption, zeta potential measurement, FTIR, Raman, XRD, XPS, SEM and EDS. After modification, the following phenomena occurred: The BET surface area, average pore diameter and total pore volume decreased; the degree of graphitization also decreased. Moreover, the presence of Fe 3 O 4 led to Fe-Ce-AC having magnetic properties, which makes it easy to separate from dye wastewater in an external magnetic field and subsequently recycle. In addition, the equilibrium isotherms and kinetics of MB adsorption on raw activated carbon and Fe-Ce-AC were systematically examined. The equilibrium adsorption data indicated that the adsorption behavior followed the Langmuir isotherm, and the pseudo-second-order model matched the kinetic data well. Compared with raw activated carbon, the maximum monolayer adsorption capacity of Fe-Ce-AC increased by 27.31%. According to the experimental results, Fe-Ce-AC can be used as an effective adsorbent for the removal of MB from dye wastewater. Copyright © 2017. Published by Elsevier B.V.

Kiss-and-Run Is a Significant Contributor to Synaptic Exocytosis and Endocytosis in Photoreceptors

PubMed Central

Wen, Xiangyi; Saltzgaber, Grant W.; Thoreson, Wallace B.

2017-01-01

Accompanying sustained release in darkness, rod and cone photoreceptors exhibit rapid endocytosis of synaptic vesicles. Membrane capacitance measurements indicated that rapid endocytosis retrieves at least 70% of the exocytotic membrane increase. One mechanism for rapid endocytosis is kiss-and-run fusion where vesicles briefly contact the plasma membrane through a small fusion pore. Release can also occur by full-collapse in which vesicles merge completely with the plasma membrane. We assessed relative contributions of full-collapse and kiss-and-run in salamander photoreceptors using optical techniques to measure endocytosis and exocytosis of large vs. small dye molecules. Incubation with small dyes (SR101, 1 nm; 3-kDa dextran-conjugated Texas Red, 2.3 nm) loaded rod and cone synaptic terminals much more readily than larger dyes (10-kDa Texas Red, 4.6 nm; 10-kDa pHrodo, 4.6 nm; 70-kDa Texas Red, 12 nm) consistent with significant uptake through 2.3–4.6 nm fusion pores. By using total internal reflection fluorescence microscopy (TIRFM) to image individual vesicles, when rods were incubated simultaneously with Texas Red and AlexaFluor-488 dyes conjugated to either 3-kDa or 10-kDa dextran, more vesicles loaded small molecules than large molecules. Using TIRFM to detect release by the disappearance of dye-loaded vesicles, we found that SR101 and 3-kDa Texas Red were released from individual vesicles more readily than 10-kDa and 70-kDa Texas Red. Although 10-kDa pHrodo was endocytosed poorly like other large dyes, the fraction of release events was similar to SR101 and 3-kDa Texas Red. We hypothesize that while 10-kDa pHrodo may not exit through a fusion pore, release of intravesicular protons can promote detection of fusion events by rapidly quenching fluorescence of this pH-sensitive dye. Assuming that large molecules can only be released by full-collapse whereas small molecules can be released by both modes, our results indicate that 50%–70% of release from rods involves kiss-and-run with 2.3–4.6 nm fusion pores. Rapid retrieval of vesicles by kiss-and-run may limit membrane disruption of release site function during ongoing release at photoreceptor ribbon synapses. PMID:28979188

Development of a Direct Spectrophotometric and Chemometric Method for Determining Food Dye Concentrations.

PubMed

Arroz, Erin; Jordan, Michael; Dumancas, Gerard G

2017-07-01

An ultraviolet visible (UV-Vis) spectrophotometric and partial least squares (PLS) chemometric method was developed for the simultaneous determination of erythrosine B (red), Brilliant Blue, and tartrazine (yellow) dyes. A training set (n = 64) was generated using a full factorial design and its accuracy was tested in a test set (n = 13) using a Box-Behnken design. The test set garnered a root mean square error (RMSE) of 1.79 × 10 -7 for blue, 4.59 × 10 -7 for red, and 1.13 × 10 -6 for yellow dyes. The relatively small RMSE suggests only a small difference between predicted versus measured concentrations, demonstrating the accuracy of our model. The relative error of prediction (REP) for the test set were 11.73%, 19.52%, 19.38%, for blue, red, and yellow dyes, respectively. A comparable overlay between the actual candy samples and their replicated synthetic spectra were also obtained indicating the model as a potentially accurate method for determining concentrations of dyes in food samples.

Removal of Congo red dye from aqueous solutions using a halloysite-magnetite-based composite.

PubMed

Ferrarini, F; Bonetto, L R; Crespo, Janaina S; Giovanela, M

2016-01-01

Adsorption has been considered as one of the most effective methods to remove dyes from aqueous solutions due to its ease of operation, high efficiency and wide adaptability. In view of all these aspects, this study aimed to evaluate the adsorption capacity of a halloysite-magnetite-based composite in the removal of Congo red dye from aqueous solutions. The effects of stirring rate, pH, initial dye concentration and contact time were investigated. The results revealed that the adsorption kinetics followed the pseudo-second-order model, and equilibrium was well represented by the Brunauer-Emmett-Teller isotherm. The thermodynamic data showed that dye adsorption onto the composite was spontaneous and endothermic and occurred by physisorption. Finally, the composite could also be regenerated at least four times by calcination and was shown to be a promising adsorbent for the removal of this dye.

Biosorption of Congo Red from aqueous solution by Bacillus weihenstephanensis RI12; effect of SPB1 biosurfactant addition on biodecolorization potency.

PubMed

Mnif, Inès; Fendri, Raouia; Ghribi, Dhouha

2015-01-01

Bacillus weihenstephanensis RI12, isolated from hydrocarbon contaminated soil, was assessed for Congo Red bio-treatment potency. Results suggested the potential of this bacterium for use in effective treatment of Congo Red contaminated wastewaters under shaking conditions at acidic and neutral pH value. The strain could tolerate higher doses of dyes as it could decolorize up to 1,000 mg/l of Congo Red. When used as microbial surfactant to enhance Congo Red biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized the decolorization efficiency at an optimal concentration of biosurfactant of about 0.075%. Studies ensured that Congo Red removal by this strain could be due to an adsorption phenomena. Germination potencies of tomato seeds using the treated dyes under different conditions showed the efficient biotreatment of the azo dye Congo Red especially with the addition of SPB1 biosurfactant. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing the effective decolorization period; the biosurfactant stimulated bacterial decolorization method may provide a highly efficient, inexpensive and time-saving procedure in the treatment of textile effluents.

Effective removal of Congo red dye from aqueous solution using modified xanthan gum/silica hybrid nanocomposite as adsorbent.

PubMed

Ghorai, Soumitra; Sarkar, Amit Kumar; Panda, A B; Pal, Sagar

2013-09-01

The aim of this work is to study the feasibility of XG-g-PAM/SiO2 nanocomposite towards its potential application as high performance adsorbent for removal of Congo red (CR) dye from aqueous solution. The surface area, average pore size and total pore volume of the developed nanocomposite has been determined. The efficiency of CR dye adsorption depends on various factors like pH, temperature of the solution, equilibrium time of adsorption, agitation speed, initial concentration of dye and adsorbent dosage. It has been observed that the nanocomposite is having excellent CR dye adsorption capacity (Q0=209.205 mg g(-1)), which is considerably high. The dye adsorption process is controlled by pseudo-second order and intraparticle diffusion kinetic models. The adsorption equilibrium data correlates well with Langmuir isotherm. Desorption study indicates the efficient regeneration ability of the dye loaded nanocomposite. Copyright © 2013 Elsevier Ltd. All rights reserved.

Certification procedures for nuclear fast red (Kernechtrot), CI 60760.

PubMed

Frank, M; Dapson, Rw; Wickersham, Tw; Kiernan, Ja

2007-02-01

Nuclear fast red (CI 60760), also known as Kernechtrot, is commonly used in conjunction with an excess of aluminum ions as a red nuclear counterstain following histochemical procedures that yield blue products. The dye has also been used as a histochemical and colorimetric reagent for calcium. Unsatisfactory samples of nuclear fast red are encountered occasionally, and confusion has resulted from applying the name of the dye to neutral red (CI 50040), an unrelated compound with different properties. Tests for the identity and performance of nuclear fast red have been developed in the laboratory of the Biological Stain Commission. The Commission will now accept samples submitted by vendors for certification. We describe here the spectrophotometric, chromatographic and biological staining methods that are used to identify and test nuclear fast red.

Molecular dynamics study of biodegradation of azo dyes via their interactions with AzrC azoreductase.

PubMed

Haghshenas, Hamed; Kay, Maryam; Dehghanian, Fariba; Tavakol, Hossein

2016-01-01

Azo dyes are one of the most important class of dyes, which have been widely used in industries. Because of the environmental pollution of azo dyes, many studies have been performed to study their biodegradation using bacterial systems. In present work, the AzrC of mesophilic gram-positive Bacillus sp. B29 has been considered to study its interaction with five common azo dyes (orange G, acid red 88, Sudan I, orange I, and methyl red). The molecular dynamics simulations have been employed to study the interaction between AzrC and azo dyes. The trajectory was confirmed using root mean square deviation and the root mean square fluctuation analyses. Then, the hydrogen bond and alanine scanning analyses were performed to reveal active site residues. Phe105 (A), Phe125 (B), Phe172 (B), and Pro132 (B) have been found as the most important hydrophobic residues whereas Asn104 (A), Tyr127 (B), and Asn187 (A) have key role in making hydrogen bond. The results of molecular mechanics Poisson-Boltzmann surface area and molecular mechanics generalized Born surface area calculations proved that the hydrophobic azo dyes like Acid red 88 binds more tightly to the AzrC protein. The calculated data suggested MR A 121 (B) I as a potential candidate for improving the AzrC-MR interactions.

Effect of light on the kinetics and equilibrium of the textile dye (Reactive Red 120) adsorption by Helianthus annuus hairy roots.

PubMed

Srikantan, Chitra; Suraishkumar, G K; Srivastava, Smita

2018-06-01

The study demonstrates for the first time that light influences the adsorption equilibrium and kinetics of a dye by root culture system. The azo dye (Reactive Red 120) adsorption by the hairy roots of H. annuus followed a pseudo first-order kinetic model and the adsorption equilibrium parameters were best estimated using Langmuir isotherm. The maximum dye adsorption capacity of the roots increased 6-fold, from 0.26 mg g -1 under complete dark conditions to 1.51 mg g -1 under 16/8 h light/dark photoperiod. Similarly, adsorption rate of the dye and removal (%) also increased in the presence of light, irrespective of the initial concentration of the dye (20-110 mg L -1 ). The degradation of the azo dye upon adsorption by the hairy roots of H. annuus was also confirmed. In addition, a strategy for simultaneous dye removal and increased alpha-tocopherol (industrially relevant) production by H. annuus hairy root cultures has been proposed and demonstrated. Copyright © 2018 Elsevier Ltd. All rights reserved.

Retinal Pigmented Epithelial Cells Cytotoxicity and Apoptosis through Activation of the Mitochondrial Intrinsic Pathway: Role Of Indocyanine Green, Brilliant Blue and Implications for Chromovitrectomy

PubMed Central

Penha, Fernando M.; Pons, Marianne; Costa, Elaine Fiod; Barros, Nilana Meza Tenório; Rodrigues, Eduardo B.; Cardoso, Emmerson Badaró; Dib, Eduardo; Maia, Mauricio; Marin-Castaño, Maria E.; Farah, Michel Eid

2013-01-01

Purpose To investigate the in vitro effect of four vital dyes on toxicity and apoptosis in a human retinal pigment epithelial (RPE) cell line. Methods ARPE-19 cells were exposed to brilliant blue (BriB), methyl blue (MetB), acid violet (AcV) and indocyanine green (ICG). Balanced salt solution was used as control. Five different concentrations of each dye (1, 0.5, 0.25, 0.05 and 0.005 mg/mL) and two exposure times (3 and 30 min) were tested. Cell viability was determined by cell count and MTS assay and cell toxicity by LDH assay. Real-time PCR and Western blotting were used to access the apoptosis process. Results ICG significantly reduced cell viability after 3 minutes of exposure at all concentrations (p<0.01). BriB was safe at concentrations up to 0.25 mg/mL and MetB at concentrations up to 0.5 mg/mL, while AcV was safe up to 0.05 mg/ml, after 3 minutes of exposure. Toxicity was higher, when the cells were treated for 30 minutes. Expression of Bax, cytochrome c and caspase-9 was upregulated at the mRNA and protein level after ICG exposure, while Bcl-2 was downregulated. AcV and MetB were similar to control. However, BriB resulted in upregulation of Bcl-2, an antiapoptotic protein. Conclusions The safest dye used on RPE cells was MetB followed by BriB and AcV. ICG was toxic at all concentrations and exposure times tested. Moreover, ICG was the only dye that induced apoptosis in ARPE-19 cells. BriB significantly increased Bcl-2 protein levels, which might protect against the apoptosis process. PMID:23675521

Wood (Bagassa guianensis Aubl) and green coconut mesocarp (cocos nucifera) residues as textile dye removers (Remazol Red and Remazol Brilliant Violet).

PubMed

Monteiro, Mônica S; de Farias, Robson F; Chaves, José Alberto Pestana; Santana, Sirlane A; Silva, Hildo A S; Bezerra, Cícero W B

2017-12-15

In this work the efficiency of two lignocellulosic waste materials, wood residues and coconut mesocarp, were investigated as adsorbents towards two representative textile dyes (Remazol Red, RR and Remazol Brilliant Violet, RBV). The moisture, carbohydrate, protein, lipid, ash and fiber contents of both natural matrices were characterized. The materials were also characterized by infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, specific surface area analysis and thermogravimetry. The adsorption of dyes was monitored by using UV-Vis spectrophotometry. It was verified that both, coconut mesocarp (CM) and wood residues can act as effective adsorbents towards the investigated dyes. It is verified that the maximum adsorption capacity Γ M (mg g -1 ) for RBV and RR are 7.28 and 3.97 towards CM and 0.64 and 0.71 towrads SD. Furthermore, it was verified that the adsorption is strongly pH dependent and, as a general behavior, an increase in the pH value is associated with a decrease of the total amount of adsorbed dye. The adsorption of violet dye onto coconut mesocarp is well described by the Langmuir model, while all the remazol red fitted better with the Freundlich equation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Decolorization of acid, disperse and reactive dyes by Trametes versicolor CBR43.

PubMed

Yang, Seung-Ok; Sodaneath, Hong; Lee, Jung-In; Jung, Hyekyeng; Choi, Jin-Hee; Ryu, Hee Wook; Cho, Kyung-Suk

2017-07-29

The mycoremediation has been considered as a promising method for decolorizing dye wastewater. To explore new bioresource for mycoremediation, a new white-rot fungus that could decolorize various dyes commonly used in textile industries was isolated, and its ligninolytic enzyme activity and decolorization capacity were characterized. The isolated CBR43 was identified as Trametes versicolor based on the morphological properties of its fruit body and spores, as well as through partial 18S rDNA gene sequences. Isolated CBR43 displayed high activities of laccase and Mn-dependent peroxidase, whereas its lignin peroxidase activity was relatively low. These ligninolytic enzyme activities in potato dextrose broth (PDB) medium were enhanced by the addition of yeast extract (1-10 g L -1 ). In particular, lignin peroxidase activity was increased more than 5 times in the PDB medium amended with 10 g L -1 of yeast extract. The CBR43 decolorized more than 90% of 200 mg L -1 acid dyes (red 114, blue 62 and black 172) and reactive dyes (red 120, blue 4, orange 16 and black 5) within 6 days in the PDB medium. CBR43 decolorized 67% of 200 mg L -1 acid orange 7 within 9 days. The decolorization efficiencies for disperse dyes (red 1, orange 3 and black 1) were 51-80% within 9 days. The CBR43 could effectively decolorize high concentrations of acid blue 62 and acid black 172 (500-700 mg L -1 ). The maximum dye decolorization rate was obtained at 28°C, pH 5, and 150 rpm in the PDB medium. T. versicolor CBR43 had high laccase and Mn-dependent peroxidase activities, and could decolorize a wide variety of dyes such as acid, disperse and reactive textile dyes. This fungus had decolorizing activities of azo-type dyes as well as anthraquinone-type dyes. T. versicolor CBR43 is one of promising bioresources for the decolorization of textile wastewater including various dyes.

TiO 2 -Assisted Photoisomerization of Azo Dyes Using Self-Assembled Monolayers: Case Study on para -Methyl Red Towards Solar-Cell Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Lei; Cole, Jacqueline M.

2014-02-18

The optical and electronic properties of a TiO2 nanoparticle-assisted photo-isomerizable surface, prepared by an azo dye/TiO2 nanocomposite film, are examined experimentally and computationally. The azo dye, para-methyl red, undergoes photoisomerization at room temperature, catalyzed by the TiO2 nanoparticle supports, while it exhibits negligible photoisomerization in solvents under otherwise identical conditions. Density functional theory and time-dependent density functional theory are employed to explain the origin of this photoisomerization in these dye…TiO2 nanoparticle self-assembled monolayers (SAMs). The device performance of these SAMs when embedded into dye-sensitized solar cells is used to further elucidate the nature of this azo dye photoisomerization and relatemore » it to the ensuing optoelectronic properties.« less

Visible to near infra red absorption in natural dye (Mondo Grass Berry) for Dye Sensitized Solar Cell

NASA Astrophysics Data System (ADS)

Pitigala, Duleepa; Desilva, L. A. A.; Perera, A. G. U.

2012-03-01

The development of dye sensitized solar cells (DSSC) is an exciting field in the low cost renewable energy production. Two major draw backs in the DSSCs are the narrow spectral response and the short term stability. Research on development of artificial dyes for broadening the response is important in finding a solution. Work presented here shows a broad spectral response with a natural dye extracted from a Mondo Grass berry (Ophiopogonjaponicus).The dye is extracted by crushing the berries and filtering to remove the pulp. A DSSC sensitized with Mondo Grass dye, and with TiO2 film screen printed on a Florien doped Tin Oxide (FTO) glass and baked for 30 minutes at 450 C as the working electrode and Iodine/triiodide red-ox electrolyte as the hole collector was tested for its performance. An open circuit photovoltage of 495 mV and a short circuit photocurrent of 0.6 mA/cm2were observed under a simulated lamp equivalent to 1 sun illumination. The broad spectral response from 400 nm to 750 nm was also observed for the Mondo Grass dye compared to other natural dyes consists of anthocyanins or tannins.

Photophysical Characterization and BSA Interaction of Direct Ring Carboxy Functionalized Symmetrical squaraine Dyes

NASA Astrophysics Data System (ADS)

Saikiran, Maryala; Pandey, Shyam S.; Hayase, Shuzi; Kato, Tamaki

2017-11-01

A series of far-red sensitive symmetrical squaraine dyes bearing direct -COOH functionalized indole ring were synthesized, characterized and subjected to photophysical investigations. These symmetrical squaraine dyes were then subjected to investigate their interaction with bovine serum albumin (BSA) in Phosphate buffer solutions. All the squaraine dyes under investigation exhibit intense and sharp optical absorption mainly in the far-red wavelength region from 550 nm -700 nm having very high molar extinction coefficients from 1.3 × 105 dm3.mol-1.cm-1. A very small Stokes shift of 10-17 nm indicates the rigid conformational structure of squaraine chromophore. Interaction of these dyes with BSA leads to not only enhanced emission intensity but also bathochromically shifted absorption maximum due to formation of dye-BSA conjugate. These dyes bind strongly with BSA having about an order of magnitude higher binding constant as compared to the reported squaraine dyes. Amongst the symmetrical squaraine dyes investigated in this work one bearing substituents like trifluorobutyl as alkyl chain at N-position of indole ring and carboxylic acid on benzene ring at the terminal (SQ-26) exhibited highest association with the BSA having very high binding constant 8.01 × 106 M-1.

Performance evaluation of two Aspergillus spp. for the decolourization of reactive dyes by bioaccumulation and biosorption.

PubMed

Mathur, Megha; Gola, Deepak; Panja, Rupobrata; Malik, Anushree; Ahammad, Shaikh Ziauddin

2018-01-01

A biological method was adopted to decolourize textile dyes, which is an economic and eco-friendly technology for textile wastewater remediation. Two fungal strains, i.e. Aspergillus lentulus and Aspergillus fumigatus, were used to study the removal of low to high concentrations (25 to 2000 mg L -1 ) of reactive remazol red, reactive blue and reactive yellow dyes by biosorption and bioaccumulation. The biosorption was successful only at the lower concentrations. A. lentulus was capable of removing 67-85% of reactive dyes during bioaccumulation mode of treatment at 500 mg L -1 dye concentration with an increased biomass uptake capacity. To cope up with the high dye concentration of 2000 mg L -1 , a novel combined approach was successful in case of A. lentulus, where almost 76% removal of reactive remazol red dye was observed during bioaccumulation followed by biosorption. The scanning electron microscopy also showed the accumulation of dye on the surface of fungal mycelium. The results signify the application of such robust fungal strains for the removal of high concentration of dyes in the textile wastewaters.

Diffusion and imaging properties of three new lipophilic tracers, NeuroVue ™ Maroon, NeuroVue ™ Red and NeuroVue ™ Green and their use for double and triple labeling of neuronal profile.

PubMed Central

Fritzsch, B.; Muirhead, K.A.; Feng, Feng; D.Gray, B.; Ohlsson-Wilhelm, B. M.

2006-01-01

We describe here diffusion and imaging properties of three new lipophilic tracers, NeuroVue ™ Maroon (near infrared), NeuroVue ™ Red and NeuroVue ™ Green. Using pair wise comparisons between the new dyes and existing dyes (DiI, DiA, DiD, DiO, PKH2, PKH26) applied to the left and the right side of fixed spinal cord preparations, we show that NeuroVue Maroon (excitation max 647 nm) surpasses all other dyes in this study in signal to noise ratio. We also present data showing the utility of these new dyes for both double labeling and triple labeling in combination with each other or existing lipophilic tracers. Using mice bearing the PLP-eGFP transgene, we demonstrate that either NeuroVue Maroon or NeuroVue Red can readily be combined with eGFP labeling. Double labeling experiments using NeuroVue Red and eGFP allowed us to demonstrate that every fiber in the neonatal ear is surrounded by developing Schwann cells. PMID:16023922

Fabrication of core-shell structured magnetic nanocellulose base polymeric ionic liquid for effective biosorption of Congo red dye.

PubMed

Beyki, Mostafa Hossein; Bayat, Mehrnoosh; Shemirani, Farzaneh

2016-10-01

Ionic liquids are considered to be a class of environmentally friendly compounds as combination of them with bioresource polymeric substances such as; cellulose, constitute emerging coating materials. Biosorption by polymeric ionic liquids exhibits an attractive green way that involves low cost and irrespective of toxicity. As a result, a novel polymeric ionic liquid has been developed by the reaction of one step synthesized Fe3O4-cellulose nanohybrid, epichlorohydrin and 1-methylimidazole and employed as a green sorbent for efficient biosorption of Congo red dye. Effective parameters on dye removing as well as their interactions were determined with response surface methodology (RSM). Congo red adsorption showed fast equilibrium time (11min) with maximum uptake of 131mgg(-1). Isotherm study revealed that Langmuir adsorption model can better describe dye adsorption behavior. Regeneration of the sorbent was performed with a mixture of methanol-acetone-NaOH (3.0molL(-1)) solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dimeric fluorescent energy transfer dyes comprising asymmetric cyanine azole-indolenine chromophores

DOEpatents

Glazer, Alexander N.; Benson, Scott C.

1996-01-01

Novel fluorescent DNA-staining dyes are provided combining asymmetric cyanine azole-indolenine dyes, which provide for strong DNA affinity, large Stokes shifts and emission in the red region of the spectrum. The dyes find particular application in gel electrophoresis and for labels which may be bound to a variety of compositions in a variety of contexts.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weeks, J.M.; Svendsen, C.

A simple subcellular histochemical staining technique employing the lysosomal probe neutral red has been developed for use with the epiendogeic earthworm Lumbricus rubellus Hoffmeister. Coelomocytes extracted from the coelomic cavity of earthworms into an isotonic earthworm Ringer solution were allowed to adhere to a microscope slide for 30 s before the application of a neutral red dye. This red dye was rapidly accumulated within the lysosomes. Observation of the loss of this dye from these lysosomes into the surrounding cytosol has enabled the quantification of the degree of lysosomal damage caused to earthworms with exposure to an increasing range ofmore » soil copper concentrations, in both laboratory and mesocosm studies. This simple in vitro biomarker has potential for the rapid assessment of the toxic effects to earthworms from soils contaminated with heavy metals and metalloids.« less

Toxicity of xanthene food dyes by inhibition of human drug-metabolizing enzymes in a noncompetitive manner.

PubMed

Mizutani, Takaharu

2009-01-01

The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC(50) values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC(50) values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of (1)O(2) originating on xanthene dyes by light irradiation, because inhibition was prevented by (1)O(2) quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin.

Toxicity of Xanthene Food Dyes by Inhibition of Human Drug-Metabolizing Enzymes in a Noncompetitive Manner

PubMed Central

Mizutani, Takaharu

2009-01-01

The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of 1O2 originating on xanthene dyes by light irradiation, because inhibition was prevented by 1O2 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin. PMID:20041016

Mechanisms of Alizarin Red S and Methylene blue biosorption onto olive stone by-product: Isotherm study in single and binary systems.

PubMed

Albadarin, Ahmad B; Mangwandi, Chirangano

2015-12-01

The biosorption process of anionic dye Alizarin Red S (ARS) and cationic dye methylene blue (MB) as a function of contact time, initial concentration and solution pH onto olive stone (OS) biomass has been investigated. Equilibrium biosorption isotherms in single and binary systems and kinetics in batch mode were also examined. The kinetic data of the two dyes were better described by the pseudo second-order model. At low concentration, ARS dye appeared to follow a two-step diffusion process, while MB dye followed a three-step diffusion process. The biosorption experimental data for ARS and MB dyes were well suited to the Redlich-Peterson isotherm. The maximum biosorption of ARS dye, qmax = 16.10 mg/g, was obtained at pH 3.28 and the maximum biosorption of MB dye, qmax = 13.20 mg/g, was observed at basic pH values. In the binary system, it was indicated that the MB dye diffuses firstly inside the biosorbent particle and occupies the biosorption sites forming a monodentate complex and then the ARS dye enters and can only bind to untaken sites; forms a tridentate complex with OS active sites. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cross-linked beads of activated oil palm ash zeolite/chitosan composite as a bio-adsorbent for the removal of methylene blue and acid blue 29 dyes.

PubMed

Khanday, W A; Asif, M; Hameed, B H

2017-02-01

Cross-linked beads of activated oil palm ash zeolite/chitosan (Z-AC/C) composite were prepared through the hydrothermal treatment of NaOH activated oil palm ash followed by beading with chitosan. The effects of initial dye concentration (50-400mg/L), temperature (30°C-50°C) and pH (3-13) on batch adsorption of methylene blue (MB) and acid blue 29 (AB29) were studied. Adsorption of both dyes was better described by Pseudo-second-order kinetics and Freundlich isotherm model. The maximum adsorption capacities of Z-AC/C were 151.51, 169.49, and 199.20mg/g for MB and 212.76, 238.09, and 270.27mg/g for AB29 at 30°C, 40°C, and 50°C, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Carbon composite lignin-based adsorbents for the adsorption of dyes.

PubMed

Wang, Xiaohong; Jiang, Chenglong; Hou, Bingxia; Wang, Yingying; Hao, Chen; Wu, Jingbo

2018-05-10

Carbon composite lignin-based adsorbent were prepared through hydrothermal method with glucose as carbon source, calcium lignosulfonate and triethylene tetramine as raw materials, respectively. The optimum synthesis conditions were determined by investigating the addition of carbon and triethylene tetramine. The adsorbent was used for the adsorption of azo dyes Congo red and Eriochrome blue black R, and the five factors affecting the adsorption were discussed, including pH of dyes, initial concentration, adsorption time, adsorption temperature and adsorbent dosage. The corresponding adsorption mechanism such as pseudo first order kinetics, pseudo second order kinetics, intraparticle diffusion, Langmuir adsorption isotherm, Freundlich isotherm, Temkin isotherm, Dubinin-Radushkevich adsorption isotherm, thermodynamics were also studied. When the dye concentration is 40 mg L -1 , Congo red and Eriochrome blue black R dye removal rates reach 99%. Moreover, the adsorption process of two kinds of dyes follow the pseudo second order kinetics and the Langmuir adsorption isotherm. Copyright © 2018 Elsevier Ltd. All rights reserved.

On the heterogeneity of fluorescence lifetime of room temperature ionic liquids: onset of a journey for exploring red emitting dyes.

PubMed

Ghosh, Anup; Chatterjee, Tanmay; Mandal, Prasun K

2012-06-25

An excitation and emission wavelength dependent non-exponential fluorescence decay behaviour of room temperature ionic liquids (RTILs) has been noted. Average fluorescence lifetimes have been found to vary by a factor of three or more. Red emitting dyes dissolved in RTILs are found to follow hitherto unobserved single exponential fluorescence decay behaviour.

Organic pollutants removal from 2,4,6-trinitrotoluene (TNT) red water using low cost activated coke.

PubMed

Zhang, Mohe; Zhao, Quanlin; Ye, Zhengfang

2011-01-01

We treated 2,4,6-trinitrotoluene (TNT) red water from the Chinese explosive industry with activated coke (AC) from lignite. Since the composition of TNT red water was very complicated, chemical oxygen demand (COD) was used as the index for evaluating treatment efficiency. This study focused on sorption kinetics and equilibrium sorption isotherms of AC for the removal of COD from TNT red water, and the changes of water quality before and after adsorption were evaluated using high performance liquid chromatography, UV-Vis spectra and gas chromatography/mass spectroscopy. The results showed that the sorption kinetics of COD removal from TNT red water onto AC fitted well with the pseudo second-order model. The adsorption process was an exothermic and physical process. The sorption isotherm was in good agreement with Redlich-Peterson isotherm. At the conditions of initial pH = 6.28, 20 degrees C and 3 hr of agitation, under 160 g/L AC, 64.8% of COD was removed. The removal efficiencies of 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO3-) and 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO3-) were 80.5% and 84.3%, respectively. After adsorption, the acute toxicity of TNT red water reduced greatly, compared with that of unprocessed TNT red water.

Magnetic removal of dyes from aqueous solution using multi-walled carbon nanotubes filled with Fe2O3 particles.

PubMed

Qu, Song; Huang, Fei; Yu, Shaoning; Chen, Gang; Kong, Jilie

2008-12-30

The Fe2O3 nanoparticles have been introduced into the multi-walled carbon nanotubes (MWCNTs) via wet chemical method. The resulting products are characterized by TEM, EDX, XRD and VSM. The magnetic MWCNTs have been employed as adsorbent for the magnetic separation of dye contaminants from water. The adsorption test of dyes (Methylene Blue and Neutral Red) demonstrates that it only takes 60min to attain equilibrium and the adsorption capacities for Methylene Blue and Neutral Red in the concentration range studied are 42.3 and 77.5mg/g, respectively. The magnetic MWCNTs can be easily manipulated in magnetic field for desired separation, leading to the removal of dyes from polluted water. The integration of MWCNTs with Fe2O3 nanoparticles has great potential application to remove organic dyes from polluted water.

New physicochemical interpretations for the adsorption of food dyes on chitosan films using statistical physics treatment.

PubMed

Dotto, G L; Pinto, L A A; Hachicha, M A; Knani, S

2015-03-15

In this work, statistical physics treatment was employed to study the adsorption of food dyes onto chitosan films, in order to obtain new physicochemical interpretations at molecular level. Experimental equilibrium curves were obtained for the adsorption of four dyes (FD&C red 2, FD&C yellow 5, FD&C blue 2, Acid Red 51) at different temperatures (298, 313 and 328 K). A statistical physics formula was used to interpret these curves, and the parameters such as, number of adsorbed dye molecules per site (n), anchorage number (n'), receptor sites density (NM), adsorbed quantity at saturation (N asat), steric hindrance (τ), concentration at half saturation (c1/2) and molar adsorption energy (ΔE(a)) were estimated. The relation of the above mentioned parameters with the chemical structure of the dyes and temperature was evaluated and interpreted. Copyright © 2014 Elsevier Ltd. All rights reserved.

FluoroMyelin™ Red is a bright, photostable and non-toxic fluorescent stain for live imaging of myelin

PubMed Central

Monsma, Paula C.; Brown, Anthony

2012-01-01

FluoroMyelin™ Red is a commercially available water-soluble fluorescent dye that has selectivity for myelin. This dye is marketed for the visualization of myelin in brain cryosections, though it is also used widely to stain myelin in chemically fixed tissue. Here we have investigated the suitability of FluoroMyelin™ Red as a vital stain for live imaging of myelin in myelinating co-cultures of Schwann cells and dorsal root ganglion neurons. We show that addition of FluoroMyelin™ Red to the culture medium results in selective staining of myelin sheaths, with an optimal staining time of 2 hours, and has no apparent adverse effect on the neurons, their axons, or the myelinating cells at the light microscopic level. The fluorescence is bright and photostable, permitting long-term time-lapse imaging. After rinsing the cultures with medium lacking FluoroMyelin™ Red, the dye diffuses out of the myelin with a half life of about 130 minutes resulting in negligible fluorescence remaining after 18–24 hours. In addition, the large Stokes shift exhibited by FluoroMyelin™ Red makes it possible to readily distinguish it from popular and widely used green and red fluorescent probes such as GFP and mCherry. Thus FluoroMyelin™ Red is a useful reagent for live fluorescence imaging studies on myelinated axons. PMID:22743799

Jute stick powder as a potential biomass for the removal of congo red and rhodamine B from their aqueous solution.

PubMed

Panda, Gopal C; Das, Sujoy K; Guha, Arun K

2009-05-15

Jute stick powder (JSP) has been found to be a promising material for adsorptive removal of congo red (C.I. 22120) and rhodamine B (C.I. 45170) from aqueous solutions. Physico-chemical parameters like dye concentration, solution pH, temperature and contact time have been varied to study the adsorption phenomenon. Favorable adsorption occurs at around pH 7.0 whereas temperature has no significant effect on adsorption of both the dyes. The maximum adsorption capacity has been calculated to be 35.7 and 87.7mg/g of the biomass for congo red and rhodamine B, respectively. The adsorption process is in conformity with Freundlich and Langmuir isotherms for rhodamine B whereas congo red adsorption fits well to Langmuir isotherm only. In both the cases, adsorption occurs very fast initially and attains equilibrium within 60min. Kinetic results suggest the intra-particle diffusion of dyes as rate limiting step.

Sorption of hydrophilic dyes on anodic aluminium oxide films and application to pH sensing.

PubMed

Silina, Yuliya E; Kuchmenko, Tatyana A; Volmer, Dietrich A

2015-02-07

The sorption of selected hydrophilic pH-sensitive dyes (bromophenol blue, bromothymol blue, bromocresol purple, alizarin red, methyl orange, congo red, rhodamine 6G) on films of anodized aluminium oxide (AAO) was investigated in this study. Depth and pore structure of the AAO channels were adjusted by changing electrolysis time and current density during treatment of aluminium foil in oxalic acid, sulfosalycilic acid and sulfuric acid at concentration levels between 0.2 and 0.6 M. The dyes were immobilized on the AAO surface by direct saturation of the films in dye solutions. It was shown by scanning electron microscopy and X-ray spectral analysis that the dyes penetrated into the AAO channels by more than 1.5 μm, even at static saturation conditions. The anionic dyes linked to the porous AAO surface exhibited differential shifts of the UV absorption bands in their acidic/basic forms. By combining several dyes, the films have an application range between pH = 0.5-9 in aqueous media. The dye-modified AAO film was a simple, portable, inexpensive and reusable pH sensor with very fast response time and clear colour transitions.

Bioremoval of the azo dye Congo Red by the microalga Chlorella vulgaris.

PubMed

Hernández-Zamora, Miriam; Cristiani-Urbina, Eliseo; Martínez-Jerónimo, Fernando; Perales-Vela, Hugo Virgilio; Ponce-Noyola, Teresa; Montes-Horcasitas, María del Carmen; Cañizares-Villanueva, Rosa Olivia

2015-07-01

Discharge of dye-containing wastewater by the textile industry can adversely affect aquatic ecosystems and human health. Bioremoval is an alternative to industrial processes for detoxifying water contaminated with dyes. In this work, active and inactive biomass of the microalga Chlorella vulgaris was assayed for the ability to remove Congo Red (CR) dye from aqueous solutions. Through biosorption and biodegradation processes, Chlorella vulgaris was able to remove 83 and 58 % of dye at concentrations of 5 and 25 mg L(-1), respectively. The maximum adsorption capacity at equilibrium was 200 mg g(-1). The Langmuir model best described the experimental equilibrium data. The acute toxicity test (48 h) with two species of cladocerans indicated that the toxicity of the dye in the effluent was significantly decreased compared to the initial concentrations in the influent. Daphnia magna was the species less sensitive to dye (EC50 = 17.0 mg L(-1)), followed by Ceriodaphnia dubia (EC50 = 3.32 mg L(-1)). These results show that Chlorella vulgaris significantly reduced the dye concentration and toxicity. Therefore, this method may be a viable option for the treatment of this type of effluent.

Comparative study on ultrasonic assisted adsorption of dyes from single system onto Fe3O4 magnetite nanoparticles loaded on activated carbon: Experimental design methodology.

PubMed

Bagheri, Ahmad Reza; Ghaedi, Mehrorang; Asfaram, Arash; Bazrafshan, Ali Akbar; Jannesar, Ramin

2017-01-01

The present study the ultrasound assisted adsorption of dyes in single system onto Fe 3 O 4 magnetite nanoparticles loaded on activated carbon (Fe 3 O 4 -MNPs-AC) was described following characterization and identification of this adsorbent by conventional techniques likes field emission scanning electron microscopy, transmission electron microscopy, particle-size distribution, X-ray diffraction and Fourier transform infrared spectroscopy. A central composite design in conjunction with a response surface methodology according to f-test and t-test for recognition and judgment about significant term led to construction of quadratic model which represent relation among responses and effective terms. This model has unique ability to predict adsorption data behavior over a large space around central and optimum point. Accordingly Optimum conditions for well and quantitative removal of present dyes was obtained best operation and conditions: initial SY, MB and EB dyes concentration of 15, 15 and 25mgL -1 , 4.0, 6.0 and 5.0 of pH, 360, 360 and 240s sonication time and 0.04, 0.03 and 0.032g of Fe 3 O 4 -MNPs-AC. Replication of similar experiment (N=5) guide that average removal percentage of SY, MB and EB were found to be 96.63±2.86%, 98.12±1.67% and 99.65±1.21% respectively. Good agreement and closeness of Predicted and experimental result and high adsorption capacity of dyes in short time strongly confirm high suitability of present method for waste water treatment, while easy separation of present nanoparticle and its good regeneration all support good applicability of Fe 3 O 4 -MNPs-AC for waste water treatment. The kinetic study can be represented by combination of pseudo second-order and intraparticle diffusion. The obtained maximum adsorption capacities correspond to Langmuir as best model for representation of experimental data correspond to dyes adsorption onto Fe 3 O 4 -MNPs-AC were 76.37, 78.76 and 102.00mgg -1 for SY, MB and EB, respectively. In addition, the performance comparison of ultrasound-assisted, magnetic stirrer assisted and vortex assisted adsorption methods demonstrates that ultrasound is an effective and good choice for facilitation of adsorption process via. Compromise of simple and facile diffusion. Copyright © 2016 Elsevier B.V. All rights reserved.

Experimental design and modeling of ultrasound assisted simultaneous adsorption of cationic dyes onto ZnS: Mn-NPs-AC from binary mixture.

PubMed

Asfaram, Arash; Ghaedi, Mehrorang; Yousefi, Fakhri; Dastkhoon, Mehdi

2016-11-01

The manganese impregnated zinc sulfide nanoparticles deposited on activated carbon (ZnS: Mn-NPs-AC) which fully was synthesized and characterized successfully applied for simultaneous removal of malachite green and methylene blue in binary situation. The effects of variables such as pH (2.0-10.0), sonication time (1-5min), adsorbent mass (0.005-0.025g) and MB and MG concentration (4-20mgL(-1)) on their removal efficiency was studied dy central composite design (CCD) to correlate dyes removal percentage to above mention variables that guides amongst the maximum influence was seen by changing the sonication time and adsorbent mass. Sonication time, adsorbent mass and pH in despite of dyes concentrations has positive relation with removal percentage. Multiple regression analysis of the experimental results is associated with 3-D response surface and contour plots that guide setting condition at pH of 7.0, 3min sonication time, 0.025g Mn: ZnS-NPs-AC and 15mgL(-1) of MB and MG lead to achievement of removal efficiencies of 99.87% and 98.56% for MG and MB, respectively. The pseudo-second-order model as best choice efficiency describe the dyes adsorption behavior, while MG and MB maximum adsorption capacity according to Langmuir was 202.43 and 191.57mgg(-1). Copyright © 2016 Elsevier B.V. All rights reserved.

Extended Fluorescent Resonant Energy Transfer in DNA Constructs

NASA Astrophysics Data System (ADS)

Oh, Taeseok

This study investigates the use of surfactants and metal cations for the enhancement of long range fluorescent resonant energy transfer (FRET) and the antenna effect in DNA structures with multiple fluorescent dyes. Double-stranded (ds) DNA structures were formed by hybridization of 21mer DNA oligonucleotides with different arrangements of three fluorescent TAMRA donor dyes with two different complementary 21mer oligonucleotides with one fluorescent TexasRed acceptor dye. In such DNA structures, hydrophobic interactions between the fluorescent dyes in close proximity produces dimerization which along with other quenching mechanisms leads to significant reduction of fluorescent emission properties. Addition of the surfactants Triton X-100, cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) along with sodium cations (Na+) and divalent magnesium cations (Mg 2+) were tested for their ability to reduce quenching of the fluorescent dyes and improve overall fluorescent emission, the long range FRET and the antenna effect properties. When the neutral (uncharged) surfactant Triton X-100 was added to the FRET ds-DNA hybrid structures with three TAMRA donors and one TexasRed acceptor, dye dimerization and emission quenching remained unaffected. However, for the positively charged CTAB surfactant at concentrations of 100 uM or higher, the neutralization of the negatively charged ds-DNA backbone by the cationic surfactant micelles was found to reduce TAMRA dye dimerization and emission quenching and improve TexasRed quantum yield, resulting in much higher FRET efficiencies and an enhanced antenna effect. This improvement is likely due to the CTAB molecules covering or sheathing the fluorescent donor and acceptor dyes which breaks up the dimerized dye complexes and prevents further quenching from interactions with water molecules and guanine bases in the DNA structure. While the negatively charged SDS surfactant alone was not able to reduce dimerization and emission quenching due to repulsive forces between DNA and SDS micelles, the addition of cations such as sodium ions (Na+) and divalent magnesium ions (Mg2+) did lead to a significant reduction in the dimerization and emission quenching resulting in much higher FRET efficiency and an enhanced antenna effect. It appears that when the repulsive electrostatic forces are screened by the cations (Mg2+ in particular), the SDS micelles can approach the FRET ds-DNA structures thereby sheathing or insulating the TAMRA and TexasRed dyes. Overall, the study provides a viable strategy for using combinations of surfactants and cations to reduce adverse fluorescent dye and other quenching mechanisms and improve the overall long distance FRET efficiency and the antenna effect in DNA structures with multi-donor and single acceptor fluorescent dye groups.

Energy transfer by way of an exciplex intermediate in flexible boron dipyrromethene-based allosteric architectures.

PubMed

Mula, Soumyaditya; Elliott, Kristopher; Harriman, Anthony; Ziessel, Raymond

2010-10-07

We have designed and synthesized a series of modular, dual-color dyes comprising a conventional boron dipyrromethene (Bodipy) dye, as a yellow emitter, and a Bodipy dye possessing extended conjugation that functions as a red emitter. A flexible tether of variable length, built from ethylene glycol residues, connects the terminal dyes. A critical design element of this type of dyad relates to a secondary amine linkage interposed between the conventional Bodipy and the tether. Cyclic voltammetry shows both Bodipy dyes to be electroactive and indicates that the secondary amine is quite easily oxidized. The ensuing fluorescence quenching is best explained in terms of the rapid formation of an intermediate charge-transfer state. In fact, exciplex-type emission is observed in weakly polar solvents and over a critical temperature range. In the dual-color dyes, direct excitation of the yellow emitter results in the appearance of red fluorescence, indicating that the exciplex is likely involved in the energy-transfer event, and provides for a virtual Stokes shift of 5000 cm(-1). Replacing the red emitter with a higher energy absorber (namely, pyrene) facilitates the collection of near-UV light and extends the virtual Stokes shift to 8000 cm(-1). Modulation of the efficacy of intramolecular energy transfer is achieved by preorganization of the connector in the presence of certain cations. This latter behavior, which is fully reversible, corresponds to an artificial allosteric effect.

Effect of Molecular Coupling on Ultrafast Electron-Transfer and Charge-Recombination Dynamics in a Wide-Gap ZnS Nanoaggregate Sensitized by Triphenyl Methane Dyes.

PubMed

Debnath, Tushar; Maity, Partha; Dana, Jayanta; Ghosh, Hirendra N

2016-03-03

Wide-band-gap ZnS nanocrystals (NCs) were synthesized, and after sensitizing the NCs with series of triphenyl methane (TPM) dyes, ultrafast charge-transfer dynamics was demonstrated. HRTEM images of ZnS NCs show the formation of aggregate crystals with a flower-like structure. Exciton absorption and lumimescence, due to quantum confinement of the ZnS NCs, appear at approximately 310 and 340 nm, respectively. Interestingly, all the TPM dyes (pyrogallol red, bromopyrogallol red, and aurin tricarboxylic acid) form charge-transfer complexes with the ZnS NCs, with the appearance of a red-shifted band. Electron injection from the photoexcited TPM dyes into the conduction band of the ZnS NCs is shown to be a thermodynamically viable process, as confirmed by steady-state and time-resolved emission studies. To unravel charge-transfer (both electron injection and charge recombination) dynamics and the effect of molecular coupling, femtosecond transient absorption studies were carried out in TPM-sensitized ZnS NCs. The electron-injection dynamics is pulse-width-limited in all the ZnS/TPM dye systems, however, the back electron transfer differs, depending on the molecular coupling of the sensitizers (TPM dyes). The detailed mechanisms for the above-mentioned processes are discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In-situ spectroscopic analysis of the traditional dyeing pigment Turkey red inside textile matrix

NASA Astrophysics Data System (ADS)

Meyer, M.; Huthwelker, T.; Borca, C. N.; Meßlinger, K.; Bieber, M.; Fink, R. H.; Späth, A.

2018-03-01

Turkey red is a traditional pigment for textile dyeing and its use has been proven for various cultures within the last three millennia. The pigment is a dye-mordant complex consisting of Al and an extract from R. tinctorum that contains mainly the anthraquinone derivative alizarin. The chemical structure of the complex has been analyzed by various spectroscopic and crystallographic techniques for extractions from textiles or directly in solution. We present an in-situ study of Turkey red by means of μ-XRF mapping and NEXAFS spectroscopy on textile fibres dyed according to a traditional process to gain insight into the coordination chemistry of the pigment in realistic matrix. We find an octahedral coordination of Al that corresponds well to the commonly accepted structure of the Al alizarin complex derived from ex-situ studies.

Improving dyeability of modified cotton fabrics by the natural aqueous extract from red cabbage using ultrasonic energy.

PubMed

Ben Ticha, Manel; Haddar, Wafa; Meksi, Nizar; Guesmi, Ahlem; Mhenni, M Farouk

2016-12-10

The concern regarding sustainable utilization of available resources is growing due to its global importance. In this paper, the dyeability of cotton fabrics with natural colorant extracted from red cabbage was improved by applying cationic groups on cotton fibers. Modification of cotton was carried using acid tannic, Rewin Os, Denitex BC and Sera Fast as cationic agents. The dyeing process was done by ultrasonic energy. The effects of the cationising agent amount, the dye bath pH, the dyeing temperature and duration, on the sonicator dyeing quality were studied. The performances of this process were evaluated by measuring the colour yield (K/S) and the dyeing fastness of the coloured cotton. Besides, modified cotton fibers were characterized by morphology analysis (SEM) and Fourier transform infrared (FTIR) spectra and compared to untreated cotton. Moreover, a two-level full factorial design was employed to optimize the sonicator dyeing process. Mathematical model equation and statistical analysis were derived by computer simulation programming applying the least squares method using Minitab 15. Best dyeing conditions were found to be: 10%, pH 11, 60min and 100°C respectively for the Sera Fast amount, dye bath pH, dyeing duration and temperature. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study of porous silicon optical waveguides impregnated with organic dyes

NASA Astrophysics Data System (ADS)

Pirasteh, P.; Charrier, J.; Dumeige, Y.; Chaillou, A.; Guendouz, M.; Haji, L.

2007-01-01

Planar waveguides were made using oxidised porous silicon layers. Then, they were impregnated with Congo Red or Disperse Red 1 dyes. Optical losses were investigated before and after impregnation. In our case, the losses of impregnated waveguides were always higher than those of non-impregnated ones. In order to achieve a better understanding of the origin of these losses, we not only studied the absorbance of solutions which would impregnate the porous layers but also the reflectance spectra of the obtained composite materials. According to the measurements, the increase in losses in the visible spectrum depends on the intrinsic absorption of the dye while in NIR, the increase would be due to an accumulation of dried dye on the surface of the waveguide which would give rise to the surface scattering losses.

Application of contact glow discharge electrolysis method for degradation of batik dye waste Remazol Red by the addition of Fe2+ ion

NASA Astrophysics Data System (ADS)

Saksono, Nelson; Puspita, Indah; Sukreni, Tulus

2017-03-01

Contact Glow Discharge Electrolysis (CGDE) has been shown to degrade much weight organic compounds such as dyes because the production of hydroxil radical (•OH) is excess. This research aims to degrade batik dye waste Remazol Red, using CGDE method with the addition of Fe2+ ion. The addition of iron salt compounds has proven to increase process efficiency. Dye degradation is known by measure its absorbances with Spectrophotometer UV-Vis. The result of study showed that percentage degradation was 99.92% in 20 minutes which obtained by using Na2SO4 0.01 M, with addition FeSO4 0,1 gram, applied voltage 860 volt, and 1 wolfram anode 5 mm depth.

RADIATION DOSIMETER AND DOSIMETRIC METHODS

DOEpatents

Taplin, G.V.

1958-10-28

The determination of ionizing radiation by means of single fluid phase chemical dosimeters of the colorimetric type is presented. A single fluid composition is used consisting of a chlorinated hydrocarbon, an acidimetric dye, a normalizer and water. Suitable chlorinated hydrocarbons are carbon tetrachloride, chloroform, trichloroethylene, trichlorethane, ethylene dichioride and tetracbloroethylene. Suitable acidimetric indicator dyes are phenol red, bromcresol purple, and creosol red. Suitable normallzers are resorcinol, geraniol, meta cresol, alpha -tocopberol, and alpha -naphthol.

Treatability studies with granular activated carbon (GAC) and sequencing batch reactor (SBR) system for textile wastewater containing direct dyes.

PubMed

Sirianuntapiboon, Suntud; Sansak, Jutarat

2008-11-30

The GAC-SBR efficiency was decreased with the increase of dyestuff concentration or the decrease of bio-sludge concentration. The system showed the highest removal efficiency with synthetic textile wastewater (STWW) containing 40 mg/L direct red 23 or direct blue 201 under MLSS of 3,000 mg/L and hydraulic retention time (HRT) of 7.5 days. But, the effluent NO(3)(-) was higher than that of the influent. Direct red 23 was more effective than direct blue 201 to repress the GAC-SBR system efficiency. The dyes removal efficiency of the system with STWW containing direct red 23 was reduced by 30% with the increase of direct red 23 from 40 mg/L to 160 mg/L. The system with raw textile wastewater (TWW) showed quite low BOD(5) TKN and dye removal efficiencies of only 64.7+/-4.9% and 50.2+/-6.9%, respectively. But its' efficiencies could be increased by adding carbon sources (BOD(5)). The dye removal efficiency with TWW was increased by 30% and 20% by adding glucose (TWW+glucose) or Thai rice noodle wastewater (TWW+TRNWW), respectively. SRT of the systems were 28+/-1 days and 31+/-2 days with TWW+glucose and TWW+TRNWW, respectively.

Chromatic shifts in the fluorescence emitted by murine thymocytes stained with Hoechst 33342.

PubMed

Petersen, Timothy W; Ibrahim, Sherrif F; Diercks, Alan H; van den Engh, Ger

2004-08-01

Many methods in flow cytometry rely on staining DNA with a fluorescent dye to gauge DNA content. From the relative intensity of the fluorescence signature, one can then infer position in cell cycle, amount of DNA (i.e., for sperm selection), or, as in the case of flow karyotyping, to distinguish individual chromosomes. This work examines the staining of murine thymocytes with a common DNA dye, Hoechst 33342, to investigate nonlinearities in the florescence intensity as well as chromatic shifts. Murine thymocytes were stained with Hoechst 33342 and measured in a flow cytometer at two fluorescence emission bands. In other measurements, cells were stained at different dye concentrations, and then centrifuged. The supernatant was then used for a second round of staining to test the amount of dye uptake. Finally, to test for resonant energy transfer, we measured fluorescence anisotropy at two different wavelengths. The fluorescence of cells stained with Hoechst 33342 is a nonlinear process that shows an overall decrease in intensity with increased dye uptake, and spectral shift to the red. Along with the spectral shift of the fluorescence to the longer wavelengths, we document decreases in the fluorescence anisotropy that may indicate resonant energy transfer. At low concentrations, Hoechst 33342 binds to the minor groove of DNA and shows an increase in fluorescence and a blue shift upon binding. At higher concentrations, at which the dye molecules can no longer bind without overlapping, the blue fluorescence decreases and the red fluorescence increases until there is approximately one dye molecule per DNA base pair. The ratio of the blue fluorescence to the red fluorescence is an accurate indicator of the cellular dye concentration.

Textile dye decolorization using cyanobacteria.

PubMed

Parikh, Amit; Madamwar, Datta

2005-03-01

Cyanobacterial cultures isolated from sites polluted by industrial textile effluents were screened for their ability to decolorize cyclic azo dyes. Gloeocapsa pleurocapsoides and Phormidium ceylanicum decolorized Acid Red 97 and FF Sky Blue dyes by more than 80% after 26 days. Chroococcus minutus was the only culture which decolorized Amido Black 10B (55%). Chlorophyll a synthesis in all cultures was strongly inhibited by the dyes. Visible spectroscopy and TLC confirmed that color removal was due to degradation of the dyes.

Adsorption of Reactive Red M-2BE dye from water solutions by multi-walled carbon nanotubes and activated carbon.

PubMed

Machado, Fernando M; Bergmann, Carlos P; Fernandes, Thais H M; Lima, Eder C; Royer, Betina; Calvete, Tatiana; Fagan, Solange B

2011-09-15

Multi-walled carbon nanotubes and powdered activated carbon were used as adsorbents for the successful removal of Reactive Red M-2BE textile dye from aqueous solutions. The adsorbents were characterised by infrared spectroscopy, N(2) adsorption/desorption isotherms and scanning electron microscopy. The effects of pH, shaking time and temperature on adsorption capacity were studied. In the acidic pH region (pH 2.0), the adsorption of the dye was favourable using both adsorbents. The contact time to obtain equilibrium at 298K was fixed at 1h for both adsorbents. The activation energy of the adsorption process was evaluated from 298 to 323K for both adsorbents. The Avrami fractional-order kinetic model provided the best fit to the experimental data compared with pseudo-first-order or pseudo-second-order kinetic adsorption models. For Reactive Red M-2BE dye, the equilibrium data were best fitted to the Liu isotherm model. Simulated dyehouse effluents were used to check the applicability of the proposed adsorbents for effluent treatment. Copyright © 2011 Elsevier B.V. All rights reserved.

On-line SPE-UHPLC method using fused core columns for extraction and separation of nine illegal dyes in chilli-containing spices.

PubMed

Khalikova, Maria A; Satínský, Dalibor; Smidrkalová, Tereza; Solich, Petr

2014-12-01

The presented work describes the development of a simple, fast and effective on-line SPE-UHPLC-UV/vis method using fused core particle columns for extraction, separation and quantitative analysis of the nine illegal dyes, most frequently found in chilli-containing spices. The red dyes Sudan I-IV, Sudan Red 7B, Sudan Red G, Sudan Orange G, Para Red, and Methyl Red were separated and analyzed in less than 9 min without labor-consuming pretreatment procedure. The chromatographic separation was performed on Ascentis Express RP-Amide column with gradient elution using mixture of acetonitrile and water, as a mobile phase at a flow rate of 1.0 mL min(-1) and 55°C of temperature. As SPE sorbent for cleanup and pre-concentration of illegal dyes short guard fused core column Ascentis Express F5 was used. The applicability of proposed method was proven for three different chilli-containing commercial samples. Recoveries for all compounds were between 90% and 108% and relative standard deviation ranged from 1% to 4% for within- and from 2% to 6% for between-day. Limits of detection showed lower values than required by European Union regulations and were in the range of 3.3-10.3 µg L(-1) for standard solutions, 5.6-235.6 µg kg(-1) for chilli-containing spices. Copyright © 2014 Elsevier B.V. All rights reserved.

Synthesis of a Far-Red Photoactivatable Silicon-Containing Rhodamine for Super-Resolution Microscopy.

PubMed

Grimm, Jonathan B; Klein, Teresa; Kopek, Benjamin G; Shtengel, Gleb; Hess, Harald F; Sauer, Markus; Lavis, Luke D

2016-01-26

The rhodamine system is a flexible framework for building small-molecule fluorescent probes. Changing N-substitution patterns and replacing the xanthene oxygen with a dimethylsilicon moiety can shift the absorption and fluorescence emission maxima of rhodamine dyes to longer wavelengths. Acylation of the rhodamine nitrogen atoms forces the molecule to adopt a nonfluorescent lactone form, providing a convenient method to make fluorogenic compounds. Herein, we take advantage of all of these structural manipulations and describe a novel photoactivatable fluorophore based on a Si-containing analogue of Q-rhodamine. This probe is the first example of a "caged" Si-rhodamine, exhibits higher photon counts compared to established localization microscopy dyes, and is sufficiently red-shifted to allow multicolor imaging. The dye is a useful label for super-resolution imaging and constitutes a new scaffold for far-red fluorogenic molecules. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Tracking living decapod larvae: mass staining of eggs with neutral red prior to hatching.

PubMed

Øresland, V; Horobin, R W

2012-04-01

Mass staining of decapod females carrying eggs, with subsequent identification of hatched larvae in the environment, is a research tool with great potential for field ecologists wishing to track the movements of larvae. For this to be achieved, however, numerous requirements must be met. These include adequate dye solubility, short staining time, dye penetration through different tissues, dye retention within the organism, absence of toxic and behavioral effects, low visibility to predators of stained larvae, no loss of staining owing to preservatives and low cost. The dye, neutral red, appears to meet most of these requirements. This dye was used in aliquots of 0.7 g/770 ml seawater applied to the females of Norway lobster (Nephrops norvegicus) and European lobster (Homarus gammarus) for 10 min. This procedure stained lobster eggs and embryos so that hatched larvae could be distinguished easily by fluorescence microscopy from larvae that hatched from unstained eggs. Stained larvae that were preserved in 4% formaldehyde in seawater were still stained after 1 year. Larvae should not come in contact with ethanol, because it extracts the dye rapidly.

Infiltration in unsaturated layered fluvial deposits at Rio Bravo : photo essay and data summary.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brainard, James Robert; Glass, Robert John, Jr.

2007-08-01

An infiltration and dye transport experiment was conducted to visualize flow and transport processes in a heterogeneous, layered, sandy-gravelly fluvial deposit adjacent to Rio Bravo Boulevard in Albuquerque, NM. Water containing red dye followed by blue-green dye was ponded in a small horizontal zone ({approx}0.5 m x 0.5 m) above a vertical outcrop ({approx}4 m x 2.5 m). The red dye lagged behind the wetting front due to slight adsorption thus allowing both the wetting front and dye fronts to be observed in time at the outcrop face. After infiltration, vertical slices were excavated to the midpoint of the infiltrometermore » exposing the wetting front and dye distribution in a quasi three-dimensional manner. At small-scale, wetting front advancement was influenced by the multitude of local capillary barriers within the deposit. However at the scale of the experiment, the wetting front appeared smooth with significant lateral spreading {approx} twice that in the vertical, indicating a strong anisotropy due to the pronounced horizontal layering. The dye fronts exhibited appreciably more irregularity than the wetting front, as well as the influence of preferential flow features (a fracture) that moved the dye directly to the front, bypassing the fresh water between.« less

Pollinator Competition as a Driver of Floral Divergence: An Experimental Test.

PubMed

Temeles, Ethan J; Newman, Julia T; Newman, Jennifer H; Cho, Se Yeon; Mazzotta, Alexandra R; Kress, W John

2016-01-01

Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants.

Pollinator Competition as a Driver of Floral Divergence: An Experimental Test

PubMed Central

Temeles, Ethan J.; Newman, Julia T.; Newman, Jennifer H.; Cho, Se Yeon; Mazzotta, Alexandra R.; Kress, W. John

2016-01-01

Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants. PMID:26814810

In vitro photoacoustic measurement of hemoglobin oxygen saturation using a single pulsed broadband supercontinuum laser source.

PubMed

Lee, Changho; Jeon, Mansik; Jeon, Min Yong; Kim, Jeehyun; Kim, Chulhong

2014-06-20

We have utilized a single pulsed broadband supercontinuum laser source to photoacoustically sense total hemoglobin concentration (HbT) and oxygen saturation of hemoglobin (SO2) in bloods in vitro. Unlike existing expensive and bulky laser systems typically used for functional photoacoustic imaging (PAI), our laser system is relatively cost-effective and compact. Instead of using two single wavelengths, two wavelength bands were applied to distinguish the concentrations of two different chromophores in the mixture. In addition, we have successfully extracted the total dye concentration and the ratio of the red dye concentration to the total dye concentration in mixed red and blue dye solutions in phantoms. The results indicate that PAI with a cheap and compact fiber based laser source can potentially provide HbT and SO2 in live animals in vivo.

Low frequency sonochemical synthesis of nanoporous amorphous manganese dioxide (MnO2) and adsorption of remazol reactive dye

NASA Astrophysics Data System (ADS)

Hasan, Siti Zubaidah; Yusop, Muhammad Rahimi; Othman, Mohamed Rozali

2015-09-01

Nanoporous amorphous-MnO2 was synthesized by sonochemical process (sonication) on the solid manganese (II) acetate tetrahydrate (Mn(CH3COO)2.4H2O) in 0.1 M KMnO4. The product was characterized by X-ray diffraction (XRD), morphology of the material was scanned by Field Emission Scanning Electron Microscopy (FE-SEM) and absorptions of MnO2 bonding was characterized by Fourier Transform Infra-Red Spectrometer (FT-IR). Remazol reactive dye or Red 3BS, was used in the adsorption study using nanoporous amorphous-MnO2. In batch experiment, 10 ppm of Remazol reactive dye was used and experiment was carried out at room temperature. Adsorption of Remazol dye on 0.2g synthesized nanoporous amorphous-MnO2 showed 99 - 100% decolorization.

Degradation of dye Procion Red MX-5B by electrolytic and electro-irradiated technologies using diamond electrodes.

PubMed

Cotillas, Salvador; Clematis, Davide; Cañizares, Pablo; Carpanese, Maria Paola; Rodrigo, Manuel A; Panizza, Marco

2018-05-01

This work focuses on the treatment of synthetic wastewater polluted with dye Procion Red MX-5B by different Electrochemical Advanced Oxidation Processes (EAOP) based on diamond anodes. The influence of the current density and the supporting electrolyte has been studied on dye removal and total mineralization of the organic matter. Results show that electrolysis with diamond electrodes is a suitable technology for an efficient degradation of dye. Nonetheless, the process efficiency increases when using chloride as supporting electrolyte because of the electrochemical generation of hypochlorite in wastewater which significantly contribute to dye removal. On the contrary, the total mineralization of the organic matter is more efficient in sulfate media. In this case, large amounts of peroxodisulfate are electrogenerated, favoring the complete removal of total organic carbon (TOC). On the other hand, lower current densities (10 mA cm -2 ) lead to a more efficient removal of both dye and TOC due to the mass transfer limitations of the technology. Finally, the coupling of UV light irradiation or ultrasound to electrolysis significantly improves the process performance, being photoelectrolysis the most efficient technology for the treatment of wastewater polluted with Procion Red MX-5B. This fact is due to the potential production of free chlorine or sulfate radicals that takes place by the activation of the electrogenerated oxidants. These species are more reactive than oxidants and, therefore, they quickly attack the organic matter present in wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

Decolourization and biodegradation of azo dye methyl red by Rhodococcus strain UCC 0016.

PubMed

Maniyam, Maegala Nallapan; Ibrahim, Abdul Latif; Cass, Anthony E G

2018-06-20

In the present study, locally isolated Rhodococcus strains were attempted as biological tools for methyl red removal, a mutagenic azo dye posing threat to the environment if left untreated. Rhodococcus strain UCC 0016 demonstrated superior methyl red-decolourizing activity of 100% after 24 hours at static condition in comparison to Rhodococcus strain UCC 0008 which recorded 65% decolourization after 72 hours. Optimization of physicochemical parameters at 30 °C, pH 7 and supplementing glucose as the carbon source resulted in improved methyl red-decolourizing activity at static condition and reduced the time taken to achieve complete decolourization by 80%. Higher concentration of methyl red (5 g/L) was able to be decolourized completely within 10 hours by adopting the technology of immobilization. The encapsulated cells of Rhodococcus strain UCC 0016 demonstrated higher substrate affinity (K m =0.6995 g/L) and accelerated rate of disappearance of methyl red (V max = 0.3203 g/L/h) compared to the free cells. Furthermore, the gellan gum beads could be reused up to 9 batches without substantial loss in the catalytic activity indicating the economic importance of this protocol. Analysis of methyl red degradation products revealed no germination inhibition on Triticum aestivum and Vigna radiata demonstrating complete toxicity removal of the parent dye after biological treatment. The occurrence of new and altered peaks (UV-Vis and FTIR) further supported the notion that the removal of methyl red by Rhodococcus strain UCC 0016 was indeed through biodegradation. Therefore, this strain has a huge potential as a candidate for efficient bioremediation of wastewater containing methyl red.

Decolorization of textile dyes in an air-lift bioreactor inoculated with Bjerkandera adusta OBR105.

PubMed

Sodaneath, Hong; Lee, Jung-In; Yang, Seung-Ok; Jung, Hyekyeng; Ryu, Hee Wook; Cho, Kyung-Suk

2017-09-19

A new decolorizing white-rot fungus, OBR105, was isolated from Mount Odae in South Korea and identified by the morphological characterization of its fruit body and spores and partial 18s rDNA sequences. The ligninolytic enzyme activity of OBR105 was studied to characterize their decolorizing mechanism using a spectrophotometric enzyme assay. For the evaluation of the decolorization capacity of OBR105, the isolate was incubated in an erlenmeyer flask and in an airlifte bioreator with potato dextrose broth (PDB) medium supplemented with each dye. In addition, the decolorization efficiency of real textile wastewater was evaluated in an airlift bioreactor inoculated with the isolate. The isolate was identified as Bjerkandera adusta and had ligninolytic enzymes such as laccase, lignin peroxidase (LiP), and Mn-dependent peroxidase (MnP). Its LiP activity was higher than its MnP and laccase activities. B. adusta OBR105 successfully decolorized reactive dyes (red 120, blue 4, orange 16, and black 5) and acid dyes (red 114, blue 62, orange 7, and black 172). B. adusta OBR105 decolorized 91-99% of 200 mg L -1 of each dye (except acid orange 7) within 3 days in a PDB medium at 28°C, pH 5, and 150 rpm. This fungus decolorized only 45% of 200 mg L -1 acid orange 7 (single azo-type dye) within 3 days, and the decolorization efficiency did not increase by prolonging the cultivation time. In the air-lift bioreactor, B. adusta OBR105 displayed a high decolorization capacity, greater than 90%, for 3 acid dyes (red 114, blue 62, and black 172) and 1 reactive dye (blue 4) within 10-15 h of treatment. B. adusta OBR105 could decolorize real textile wastewater in the air-lift bioreactor. This result suggests that an air-lift reactor employing B. adusta OBR105 is a promising bioreactor for the treatment of dye wastewater.

The structure and protein binding of amyloid-specific dye reagents.

PubMed

Stopa, Barbara; Piekarska, Barbara; Konieczny, Leszek; Rybarska, Janina; Spólnik, Paweł; Zemanek, Grzegorz; Roterman, Irena; Król, Marcin

2003-01-01

The self-assembling tendency and protein complexation capability of dyes related to Congo red and also some dyes of different structure were compared to explain the mechanism of Congo red binding and the reason for its specific affinity for beta-structure. Complexation with proteins was measured directly and expressed as the number of dye molecules bound to heat-aggregated IgG and to two light chains with different structural stability. Binding of dyes to rabbit antibodies was measured indirectly as the enhancement effect of the dye on immune complex formation. Self-assembling was tested using dynamic light scattering to measure the size of the supramolecular assemblies. In general the results show that the supramolecular form of a dye is the main factor determining its complexation capability. Dyes that in their compact supramolecular organization are ribbon-shaped may adhere to polypeptides of beta-conformation due to the architectural compatibility in this unique structural form. The optimal fit in complexation seems to depend on two contradictory factors involving, on the one hand, the compactness of the non-covalently stabilized supramolecular ligand, and the dynamic character producing its plasticity on the other. As a result, the highest protein binding capability is shown by dyes with a moderate self-assembling tendency, while those arranging into either very rigid or very unstable supramolecular entities are less able to bind.

Decolorization of Mordant red 73 azo dye in water using H2O2/UV and photo-Fenton treatment.

PubMed

Elmorsi, Taha M; Riyad, Yasser M; Mohamed, Zeinhom H; Abd El Bary, Hassan M H

2010-02-15

Decolorization of the Mordant red 73 (MR73) azo dye in water was investigated in laboratory-scale experiments using UV/H(2)O(2) and photo-Fenton treatments. Photodegradation experiments were carried out in a stirred batch photoreactor equipped with a low-pressure mercury lamp as UV source at 254 nm. The effect of operating parameters such as pH, [H(2)O(2)](,) [dye] and the presence of inorganic salts (NaNO(3), NaCl and Na(2)CO(3)) were also investigated. The results indicated that complete dye decolorization was obtained in less than 60 min under optimum conditions. Furthermore, results showed that dye degradation was dependent upon pH, [H(2)O(2)] and initial dye concentration. The presence of chloride ion led to large decreases in the photodegradation rate of MR73 while both nitrate and carbonate ions have a slight effect. The photo-Fenton treatment, in the presence of Fe powder as a source of Fe(2+) ions, was highly efficient and resulted in 99% decolorization of the dye in 15 min. Mineralization of MR73 dye was investigated by determining chemical oxygen demand (COD). In a 3h photoperiod "65%" of the dye was mineralized by the H(2)O(2)/UV process, while the photo-Fenton treatment was more efficient producing 85% mineralization over the same 3-h period.

Preconcentration of aqueous dyes through phase-transfer liquid-phase microextraction with a room-temperature ionic liquid.

PubMed

Chen, Hsiu-Liang; Chang, Shuo-Kai; Lee, Chia-Ying; Chuang, Li-Lin; Wei, Guor-Tzo

2012-09-12

In this study, we employed the room-temperature ionic liquid [bmim][PF(6)] as both ion-pair agent and an extractant in the phase-transfer liquid-phase microextraction (PTLPME) of aqueous dyes. In the PTLPME method, a dye solution was added to the extraction solution, comprising a small amount of [bmim][PF(6)] in a relatively large amount of CH(2)Cl(2), which serves as the disperser solvent to an extraction solution. Following extraction, CH(2)Cl(2) was evaporated from the extractant, resulting in the extracted dyes being concentrated in a small volume of the ionic liquid phase to increase the enrichment factor. The enrichment factors of for the dye Methylene Blue, Neutral Red, and Methyl Red were approximately 500, 550 and 400, respectively; their detection limits were 0.014, 0.43, and 0.02 μg L(-1), respectively, with relative standard deviations of 4.72%, 4.20%, and 6.10%, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

Flow and thermal characteristics of high Reynolds number (2800-17,000) dye cell: simulation and experiment.

PubMed

Mishra, G K; Kumar, Abhay; Prakash, O; Biswal, R; Dixit, S K; Nakhe, S V

2015-04-10

This paper presents computational and experimental studies on wavelength/frequency fluctuation characteristics of a high pulse repetition rate (18 kHz) dye laser pumped by a frequency-doubled Nd:YAG laser (532 nm). The temperature gradient in the dye solution is found to be responsible for wavelength fluctuations of the dye laser at low flow rates (2800

Maintenance of residual activity of Bt toxin by using natural and synthetic dyes: a novel approach for sustainable mosquito vector control.

PubMed

Chandrashekhar, Patil; Rahul, Suryawanshi; Hemant, Borase; Chandrakant, Narkhede; Bipinchandra, Salunke; Satish, Patil

2015-01-01

Mosquito control protein from Bacillus thuringiensis gets inactivated with exposure to sunlight. To address this issue, the potential of synthetic and natural dye was investigated as sunlight protectants. Bt SV2 in absence of dyes when exposed to sunlight showed reduced effectiveness against the fourth instars of mosquito larvae. Whereas acriflavin, congo red and violacein were able to maintain 86.4%, 91.6% and 82.2% mosquito larvicidal efficacy of Bt SV2 against IVth instars larvae of Anopheles stephensi Meigen after exposure to sunlight. Similarly, beetroot dye, acriflavin, congo red and violacein maintained 98.4%, 97.1%, 90.8% and 70.7% larvicidal activities against Aedes aegypti Linnaeus after sunlight exposure. Prodigiosin was found to be the best photo-protectant by simultaneously protecting and enhancing Bt activity by 6.16% and 22.16% against A. stephensi and A. aegypti, respectively. Combination of dyes with Bt formulations can be a good strategy for mosquito control programmes in tropical and sub-tropical regions.

Properties of electronically excited states of four squaraine dyes and their complexes with fullerene C70: A theoretical investigation

NASA Astrophysics Data System (ADS)

Zhang, Jian; Li, Tingyu

2017-09-01

Solar cells sensitized by polypyridyl Ru(II) complexes exhibit relatively high efficiency, however those photo-sensitizers did not absorb the photons in the far-red and near-infrared region. At present, squaraine dyes have received considerable attention as their attractively intrinsic red light absorption and unusual high molar extinction coefficient. Here we applied density functional theory and time dependent density functional theory to investigate the properties of electronically excited states of four squaraine dyes and their complexes with fullerene C70. The influences of different functionals, basis sets and solvent effects are evaluated. To understand the photophysical properties, the investigations are basing on a classification method which splits the squaraine dyes and their complexes with fullerene C70 into two units to characterize the intramolecular density distribution. We present the signatures of their electronically excited states which are characterized as local excitation or charge-transfer excitation. The relationship between open-circuit voltage and the number of intramolecular hydrogen bonds in squaraine dyes are discussed.

Detail study on ac-dc magnetic and dye absorption properties of Fe3O4 hollow spheres for biological and industrial application.

PubMed

Sarkar, Debasish; Mandal, Kalyan; Mandal, Madhuri

2014-03-01

Here solvo-thermal technique has been used to synthesize hollow-nanospheres of magnetite. We have shown that PVP plays an important role to control the particle size and also helps the particles to take the shape of hollow spheres. Structural analysis was done by XRD measurement and morphological measurements like SEM and TEM were performed to confirm the hollow type spherical particles formation and their shape and sizes were also investigated. The detail ac-dc magnetic measurements give an idea about the application of these nano spheres for hyperthermia therapy and spontaneous dye adsorption properties (Gibbs free energy deltaG0 = -0.526 kJ/mol for Eosin and -1.832 kJ/mol for MB) of these particles indicate its use in dye manufacturing company. Being hollow in structure and magnetic in nature such materials will also be useful in other application fields like in drug delivery, arsenic and heavy metal removal by adsorption technique, magnetic separation etc.

Enhanced photocatalytic activity of Fe-doped TiO2 coated on N-doped activated carbon composites for photocatalytic degradation of dyeing wastewater

NASA Astrophysics Data System (ADS)

Zhou, Jie; Zhu, Beibei; Wang, Lu; Li, Ya; Qiao, Qichen

2017-10-01

Fe-doped TiO2 coated on N-doped activated carbon (Fe-TiO2/N-AC, FTNA) composites were synthesized simply by a straightforward two-step procedure. The obtained materials were characterized by X-ray diffractometry (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and FT-IR spectroscopies. Through the degradation of dyeing wastewater, the photocatalytic activity of FTNA was investigated under ultraviolet light irradiation. The results showed that containing N functional groups were successfully introduced onto the surface of the activated carbon. Compared with Fe-TiO2/AC (FTA), FTNA with average particle size of TiO2 13.6 nm and surface area 1007.89 m2/g showed a higher photoactivity. Additionally, for the photocatalytic degradation of dyeing wastewater, the optimum N content and catalyst content were 0.8% and 5g/L, respectively. Moreover, the photoactivity and photo stability of the catalyst after many runs was also evaluated.

An ensemble and single-molecule fluorescence microscopy investigation of phase-separated monolayer films stained with Nile Red.

PubMed

Lu, Yin; Porterfield, Robyn; Thunder, Terri; Paige, Matthew F

2011-01-01

Phase-separated Langmuir-Blodgett monolayer films prepared from mixtures of arachidic acid (C19H39COOH) and perfluorotetradecanoic acid (C13F27COOH) were stained via spin-casting with the polarity sensitive phenoxazine dye Nile Red, and characterized using a combination of ensemble and single-molecule fluorescence microscopy measurements. Ensemble fluorescence microscopy and spectromicroscopy showed that Nile Red preferentially associated with the hydrogenated domains of the phase-separated films, and was strongly fluorescent in these areas of the film. These measurements, in conjunction with single-molecule fluorescence imaging experiments, also indicated that a small sub-population of dye molecules localizes on the perfluorinated regions of the sample, but that this sub-population is spectroscopically indistinguishable from that associated with the hydrogenated domains. The relative importance of selective dye adsorption and local polarity sensitivity of Nile Red for staining applications in phase-separated LB films as well as in cellular environments is discussed in context of the experimental results. Copyright © 2010 Elsevier B.V. All rights reserved.

Ultrasonic dyeing of cellulose nanofibers.

PubMed

Khatri, Muzamil; Ahmed, Farooq; Jatoi, Abdul Wahab; Mahar, Rasool Bux; Khatri, Zeeshan; Kim, Ick Soo

2016-07-01

Textile dyeing assisted by ultrasonic energy has attained a greater interest in recent years. We report ultrasonic dyeing of nanofibers for the very first time. We chose cellulose nanofibers and dyed with two reactive dyes, CI reactive black 5 and CI reactive red 195. The cellulose nanofibers were prepared by electrospinning of cellulose acetate (CA) followed by deacetylation. The FTIR results confirmed complete conversion of CA into cellulose nanofibers. Dyeing parameters optimized were dyeing temperature, dyeing time and dye concentrations for each class of the dye used. Results revealed that the ultrasonic dyeing produced higher color yield (K/S values) than the conventional dyeing. The color fastness test results depicted good dye fixation. SEM analysis evidenced that ultrasonic energy during dyeing do not affect surface morphology of nanofibers. The results conclude successful dyeing of cellulose nanofibers using ultrasonic energy with better color yield and color fastness results than conventional dyeing. Copyright © 2016 Elsevier B.V. All rights reserved.

A Transient Cell-shielding Method for Viable MSC Delivery Within Hydrophobic Scaffolds Polymerized in situ

DTIC Science & Technology

2015-03-27

cell nutrients and wastes than swollen hydrogels. While hydrophobic biomaterials such as PUR provide a generalizable, biodegradable platform for tissue...Culture of cellularized PUR scaffolds Rat BMSCs were stained with a cytoplasmic dye (VyBrant® CFDA SE Cell Tracer Kit, Life Technologies, per the...growth, adipogenic, or osteo- genic media for up to 21 days and stained with Oil Red O or Alizarin Red S. After staining, dyes were dissolved in

Methylene blue, curcumin and ion pairing nanoparticles effects on photodynamic therapy of MDA-MB-231 breast cancer cell.

PubMed

Hosseinzadeh, Reza; Khorsandi, Khatereh

2017-06-01

The aim of current study was to use methylene blue-curcumin ion pair nanoparticles and single dyes as photosensitizer for comparison of photodynamic therapy (PDT) efficacy on MDA-MB-231 cancer cells, also various light sources effect on activation of photosensitizer (PS) was considered. Ion pair nanoparticles were synthesized using opposite charge ions precipitation and lyophilized. The PDT experiments were designed and the effect of PSs and light sources (Red LED (630nm; power density: 30mWcm -2 ) and blue LED (465nm; power density: 34mWcm -2 )) on the human breast cancer cell line were examined. The effect of PS concentration (0-75μg.mL -1 ), incubation time, irradiation time and light sources, and priority in irradiation of blue or red lights were determined. The results show that the ion pairing of methylene blue and curcumin enhance the photodynamic activity of both dyes and the cytotoxicity of ion pair nanoparticles on the MDA-231 breast cancer cell line. Blue and red LED light sources were used for photo activation of photosensitizers. The results demonstrated that both dyes can activate using red light LED better than blue light LED for singlet oxygen producing. Nano scale ion pair precipitating of methylene blue-curcumin enhanced the cell penetrating and subsequently cytotoxicity of both dyes together. Copyright © 2017 Elsevier B.V. All rights reserved.

The influence of surface plasmons on fluorescence of the dye Lumogen F red 300 in condensed phase

NASA Astrophysics Data System (ADS)

Reisfeld, Renata; Levchenko, Viktoria

2017-01-01

The paper is divided to two parts one is a short description of scientific activity of Georges Boulon and my long standing friendship with him, the second part consists of the new findings of increasing fluorescence by surface plasmons studies performed recently in Jerusalem. We describe the synthesis of copper nanoparticles and their incorporation into polyvinylpyrrolidone and into sol-gel matrix co-doped with the fluorescent dye Lumogen F Red 300. The absorption and emission spectra of samples undoped and co-doped with nanoparticles reveal the increase of fluorescence of the dye in presence of copper nanoparticles. The phenomenon arises from scattered light by the nanoparticles.

Fabrication and characterization of dichroic fine crystals by the reprecipitation method

NASA Astrophysics Data System (ADS)

Iino, Tatsuya; Mori, Shunsuke; Shito, Keiji; Kimura, Ayaka; Morishita, Yoshii; Chiba, Takayuki; Katagiri, Hiroshi; Okada, Shuji; Masuhara, Akito

2018-06-01

Suspended particle devices can rapidly switch from a dark blue state to a clear state by applying AC voltage, but their maximum transmittance has to be improved. In this work, we have targeted dichroic dyes and applied the reprecipitation method to KPD-503, a trisazo dye showing little dichroism in bulk crystals despite the dye molecules having large dichroism. As a result, microcrystals showing large dichroism were obtained. These microcrystals were considered to have a kinetically stable structure and oriented by voltage in a dispersing medium.

A study of Reactive Red 198 adsorption on iron filings from aqueous solutions.

PubMed

Azhdarpoor, Abooalfazl; Nikmanesh, Roya; Khademi, Fahime

2014-01-01

In recent years, reactive dyes have been widely used in textile industries with particular efficiency. They dyes are often toxic, carcinogenic and mutagenic. Improper treatment and non-scientific disposal of dyed wastewater from these industries into water sources has created many environmental problems and concerns around the world. The purpose of the present study is to investigate the efficiency of iron filings in adsorption of Reactive Red 198 from aqueous solutions. This study was conducted using an experimental method at the laboratory scale. In this study, the effects of operating parameters such as pH (1-11), initial dye concentration (40-400 mg/L), contact time (5-120 min) and iron dose (0.1-1 g) with a mesh of<100 were studied. Dye concentration was determined using a spectrophotometer at a wavelength of 520 nm. The results indicated that maximum adsorption capacity of the dye in question was obtained at pH 3, contact time of 60 min and adsorbent dose of 1 g. At initial dye concentration of 100 and 200 mg/L, by increasing the dose of waste iron from 0.1 to 1 g, the removal percentage increased from approximately 76.89% to 97.28% and from 22.64% to 68.03%, respectively. At pH 3, contact time of 5 min and constant waste iron dose of 0.8 g, the dye removal efficiency was 85.34%. By increasing the contact time to 120 min, the removal efficiency increased to 99.2%. Welding iron waste as an inexpensive and available adsorbent has an optimum ability for adsorption of Reactive Red 198 from aqueous solutions.

Structure and reactivity of thiazolium azo dyes: UV-visible, resonance Raman, NMR, and computational studies of the reaction mechanism in alkaline solution.

PubMed

Abbott, Laurence C; Batchelor, Stephen N; Moore, John N

2013-03-07

UV-visible absorption, resonance Raman, and (1)H NMR spectroscopy, allied with density functional theory (DFT) calculations, have been used to study the structure, bonding, and alkaline hydrolysis mechanism of the cationic thiazloium azo dye, 2-[2-[4-(diethylamino)phenyl]diazenyl]-3-methyl-thiazolium (1a), along with a series of six related dyes with different 4-dialkylamino groups and/or other phenyl ring substituents (2a-c, 3a-c) and the related isothiazolium azo dye, 5-[2-[4-(dimethylamino)phenyl]diazenyl]-2-methyl-isothiazolium (4). These diazahemicyanine dyes are calculated to have a similar low-energy structure that is cis, trans at the (iso)thiazolium-azo group, and for which the calculated Raman spectra provide a good match with the experimental data; the calculations on these structures are used to assign and discuss the transitions giving rise to the experimental spectra, and to consider the bonding and its variation between the dyes. UV-visible, Raman, and NMR spectra recorded from minutes to several weeks after raising the pH of an aqueous solution of 1a to ca. 11.5 show that the dominant initial step in the reaction is loss of diethylamine to produce a quinonimine (ca. hours), with subsequent reactions occurring on longer time scales (ca. days to weeks); kinetic analyses give a rate constant of 2.6 × 10(-2) dm(3) mol(-1) s(-1) for reaction of 1a with OH(-). UV-visible spectra recorded on raising the pH of the other dyes in solution show similar changes that are attributed to the same general reaction mechanism, but with different rate constants for which the dependence on structure is discussed.

Characterisation of interaction between food colourant allura red AC and human serum albumin: multispectroscopic analyses and docking simulations.

PubMed

Wu, Di; Yan, Jin; Wang, Jing; Wang, Qing; Li, Hui

2015-03-01

Binding interaction of human serum albumin (HSA) with allura red AC, a food colourant, was investigated at the molecular level through fluorescence, ultraviolet-visible, circular dichroism (CD) and Raman spectroscopies, as well as protein-ligand docking studies to better understand the chemical absorption, distribution and transportation of colourants. Results show that allura red AC has the ability to quench the intrinsic fluorescence of HSA through static quenching. The negative values of the thermodynamic parameters ΔG, ΔH, and ΔS indicated that hydrogen bond and van der Waals forces are dominant in the binding between the food colourant and HSA. The CD and Raman spectra showed that the binding of allura red AC to HSA induces the rearrangement of the carbonyl hydrogen-bonding network of polypeptides, which changes the HSA secondary structure. This colourant is bound to HSA in site I, and the binding mode was further analysed with the use of the CDOCKER algorithm in Discovery Studio. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preparation of low cost activated carbon from Myrtus communis and pomegranate and their efficient application for removal of Congo red from aqueous solution

NASA Astrophysics Data System (ADS)

Ghaedi, Mehrorang; Tavallali, Hossein; Sharifi, Mahdi; Kokhdan, Syamak Nasiri; Asghari, Alireza

2012-02-01

In this research, the potential applicability of activated carbon prepared from Myrtus communis (AC-MC) and pomegranate (AC-PG) as useful adsorbents for the removal of Congo red (CR) from aqueous solutions in batch method was investigated. The effects of pH, contact time, agitation time and amount of adsorbents on removal percentage of Congo red on both adsorbents were examined. Increase in pH up to 6 for AC-MC and pH 7 for AC-PG increase the adsorption percentage (capacity) and reach equilibrium within 30 min of contact time. Fitting the experimental data to conventional isotherm models like Freundlich, Langmuir, Tempkin and Dubinin-Radushkevich show that the experimental data fitted very well to the Freundlich isotherm for AC-MC and Langmuir isotherm for AC-PG. Fitting the experimental data to different kinetic models such as pseudo first-order, pseudo second-order, Elovich and intraparticle diffusion mechanism showed the applicability of a pseudo second-order with involvement of intraparticle diffusion model for interpretation of experimental data for both adsorbents. The adsorption capacity of AC-PG and AC-MC for the removal of CR was found to be 19.231 and 10 mg g -1. These results clearly indicate the efficiency of adsorbents as a low cost adsorbent for treatment of wastewater containing CR.

Preparation of low cost activated carbon from Myrtus communis and pomegranate and their efficient application for removal of Congo red from aqueous solution.

PubMed

Ghaedi, Mehrorang; Tavallali, Hossein; Sharifi, Mahdi; Kokhdan, Syamak Nasiri; Asghari, Alireza

2012-02-01

In this research, the potential applicability of activated carbon prepared from Myrtus communis (AC-MC) and pomegranate (AC-PG) as useful adsorbents for the removal of Congo red (CR) from aqueous solutions in batch method was investigated. The effects of pH, contact time, agitation time and amount of adsorbents on removal percentage of Congo red on both adsorbents were examined. Increase in pH up to 6 for AC-MC and pH 7 for AC-PG increase the adsorption percentage (capacity) and reach equilibrium within 30 min of contact time. Fitting the experimental data to conventional isotherm models like Freundlich, Langmuir, Tempkin and Dubinin-Radushkevich show that the experimental data fitted very well to the Freundlich isotherm for AC-MC and Langmuir isotherm for AC-PG. Fitting the experimental data to different kinetic models such as pseudo first-order, pseudo second-order, Elovich and intraparticle diffusion mechanism showed the applicability of a pseudo second-order with involvement of intraparticle diffusion model for interpretation of experimental data for both adsorbents. The adsorption capacity of AC-PG and AC-MC for the removal of CR was found to be 19.231 and 10 mg g(-1). These results clearly indicate the efficiency of adsorbents as a low cost adsorbent for treatment of wastewater containing CR. Copyright © 2011 Elsevier B.V. All rights reserved.

Low frequency sonochemical synthesis of nanoporous amorphous manganese dioxide (MnO{sub 2}) and adsorption of remazol reactive dye

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasan, Siti Zubaidah; Yusop, Muhammad Rahimi; Othman, Mohamed Rozali, E-mail: rozali@ukm.edu.my

2015-09-25

Nanoporous amorphous-MnO{sub 2} was synthesized by sonochemical process (sonication) on the solid manganese (II) acetate tetrahydrate (Mn(CH{sub 3}COO){sub 2}.4H{sub 2}O) in 0.1 M KMnO{sub 4}. The product was characterized by X-ray diffraction (XRD), morphology of the material was scanned by Field Emission Scanning Electron Microscopy (FE-SEM) and absorptions of MnO{sub 2} bonding was characterized by Fourier Transform Infra-Red Spectrometer (FT-IR). Remazol reactive dye or Red 3BS, was used in the adsorption study using nanoporous amorphous-MnO{sub 2}. In batch experiment, 10 ppm of Remazol reactive dye was used and experiment was carried out at room temperature. Adsorption of Remazol dye onmore » 0.2g synthesized nanoporous amorphous-MnO{sub 2} showed 99 – 100% decolorization.« less

The fluorescence theatre: a cost-effective device using theatre gels for fluorescent protein and dye screening.

PubMed

Heil, John R; Nordeste, Ricardo F; Charles, Trevor C

2011-04-01

Here we report a simple cost-effective device for screening colonies on plates for expression of the monomeric red fluorescent protein mRFP1 and the fluorescent dye Nile red. This device can be built from any simple light source, in our case a Quebec Colony Counter, and cost-effective theatre gels. The device can be assembled in as little as 20 min, and it produces excellent results when screening a large number of colonies.

3D-QSPR Method of Computational Technique Applied on Red Reactive Dyes by Using CoMFA Strategy

PubMed Central

Mahmood, Uzma; Rashid, Sitara; Ali, S. Ishrat; Parveen, Rasheeda; Zaheer-ul-Haq; Ambreen, Nida; Khan, Khalid Mohammed; Perveen, Shahnaz; Voelter, Wolfgang

2011-01-01

Cellulose fiber is a tremendous natural resource that has broad application in various productions including the textile industry. The dyes, which are commonly used for cellulose printing, are “reactive dyes” because of their high wet fastness and brilliant colors. The interaction of various dyes with the cellulose fiber depends upon the physiochemical properties that are governed by specific features of the dye molecule. The binding pattern of the reactive dye with cellulose fiber is called the ligand-receptor concept. In the current study, the three dimensional quantitative structure property relationship (3D-QSPR) technique was applied to understand the red reactive dyes interactions with the cellulose by the Comparative Molecular Field Analysis (CoMFA) method. This method was successfully utilized to predict a reliable model. The predicted model gives satisfactory statistical results and in the light of these, it was further analyzed. Additionally, the graphical outcomes (contour maps) help us to understand the modification pattern and to correlate the structural changes with respect to the absorptivity. Furthermore, the final selected model has potential to assist in understanding the charachteristics of the external test set. The study could be helpful to design new reactive dyes with better affinity and selectivity for the cellulose fiber. PMID:22272108

Solid waste from leather industry as adsorbent of organic dyes in aqueous-medium.

PubMed

Oliveira, Luiz C A; Gonçalves, Maraísa; Oliveira, Diana Q L; Guerreiro, Mário C; Guilherme, Luiz R G; Dallago, Rogério M

2007-03-06

The industrial tanning of leather usually produces considerable amounts of chromium-containing solid waste and liquid effluents and raises many concerns on its environmental effect as well as on escalating landfill costs. Actually, these shortcomings are becoming increasingly a limiting factor to this industrial activity that claims for alternative methods of residue disposals. In this work, it is proposed a novel alternative destination of the solid waste, based on the removal of organic contaminants from the out coming aqueous-residue. The adsorption isotherm pattern for the wet blue leather from the Aurea tanning industry in Erechim-RS (Brazil) showed that these materials present high activity on adsorbing the reactive red textile dye as well as other compounds. The adsorbent materials were characterized by IR spectroscopy and SEM and tested for the dye adsorption (reactive textile and methylene blue dyes). The concentrations of dyes were measured by UV-vis spectrophotometry and the chromium extraction from leather waste was realized by basic hydrolysis and determined by atomic absorption. As a low cost abundant adsorbent material with high adsorption ability on removing dye methylene blue (80mgg(-1)) and textile dye reactive red (163mgg(-1)), the leather waste is revealed to be a interesting alternative relatively to more costly adsorbent materials.

Application of acidic treated pumice as an adsorbent for the removal of azo dye from aqueous solutions: kinetic, equilibrium and thermodynamic studies

PubMed Central

2012-01-01

Colored effluents are one of the important environment pollution sources since they contain unused dye compounds which are toxic and less-biodegradable. In this work removal of Acid Red 14 and Acid Red 18 azo dyes was investigated by acidic treated pumice stone as an efficient adsorbent at various experimental conditions. Removal of dye increased with increase in contact time and initial dye concentration, while decreased for increment in solution temperature and pH. Results of the equilibrium study showed that the removal of AR14 and AR18 followed Freundlich (r2>0.99) and Langmuir (r2>0.99) isotherm models. Maximum sorption capacities were 3.1 and 29.7 mg/g for AR 14 and AR18, namely significantly higher than those reported in the literature, even for activated carbon. Fitting of experimental data onto kinetic models showed the relevance of the pseudo-second order (r2>0.99) and intra-particle diffusion (r2>0.98) models for AR14 and AR18, respectively. For both dyes, the values of external mass transfer coefficient decreased for increasing initial dye concentrations, showing increasing external mass transfer resistance at solid/liquid layer. Desorption experiments confirmed the relevance of pumice stone for dye removal, since the pH regeneration method showed 86% and 89% regeneration for AR14 and AR18, respectively. PMID:23369579

Mineralization and Detoxification of the Carcinogenic Azo Dye Congo Red and Real Textile Effluent by a Polyurethane Foam Immobilized Microbial Consortium in an Upflow Column Bioreactor.

PubMed

Lade, Harshad; Govindwar, Sanjay; Paul, Diby

2015-06-16

A microbial consortium that is able to grow in wheat bran (WB) medium and decolorize the carcinogenic azo dye Congo red (CR) was developed. The microbial consortium was immobilized on polyurethane foam (PUF). Batch studies with the PUF-immobilized microbial consortium showed complete removal of CR dye (100 mg·L-1) within 12 h at pH 7.5 and temperature 30 ± 0.2 °C under microaerophilic conditions. Additionally, 92% American Dye Manufactureing Institute (ADMI) removal for real textile effluent (RTE, 50%) was also observed within 20 h under the same conditions. An upflow column reactor containing PUF-immobilized microbial consortium achieved 99% CR dye (100 mg·L-1) and 92% ADMI removal of RTE (50%) at 35 and 20 mL·h-l flow rates, respectively. Consequent reduction in TOC (83 and 79%), COD (85 and 83%) and BOD (79 and 78%) of CR dye and RTE were also observed, which suggested mineralization. The decolorization process was traced to be enzymatic as treated samples showed significant induction of oxidoreductive enzymes. The proposed biodegradation pathway of the dye revealed the formation of lower molecular weight compounds. Toxicity studies with a plant bioassay and acute tests indicated that the PUF-immobilized microbial consortium favors detoxification of the dye and textile effluents.

Mineralization and Detoxification of the Carcinogenic Azo Dye Congo Red and Real Textile Effluent by a Polyurethane Foam Immobilized Microbial Consortium in an Upflow Column Bioreactor

PubMed Central

Lade, Harshad; Govindwar, Sanjay; Paul, Diby

2015-01-01

A microbial consortium that is able to grow in wheat bran (WB) medium and decolorize the carcinogenic azo dye Congo red (CR) was developed. The microbial consortium was immobilized on polyurethane foam (PUF). Batch studies with the PUF-immobilized microbial consortium showed complete removal of CR dye (100 mg·L−1) within 12 h at pH 7.5 and temperature 30 ± 0.2 °C under microaerophilic conditions. Additionally, 92% American Dye Manufactureing Institute (ADMI) removal for real textile effluent (RTE, 50%) was also observed within 20 h under the same conditions. An upflow column reactor containing PUF-immobilized microbial consortium achieved 99% CR dye (100 mg·L−1) and 92% ADMI removal of RTE (50%) at 35 and 20 mL·h−l flow rates, respectively. Consequent reduction in TOC (83 and 79%), COD (85 and 83%) and BOD (79 and 78%) of CR dye and RTE were also observed, which suggested mineralization. The decolorization process was traced to be enzymatic as treated samples showed significant induction of oxidoreductive enzymes. The proposed biodegradation pathway of the dye revealed the formation of lower molecular weight compounds. Toxicity studies with a plant bioassay and acute tests indicated that the PUF-immobilized microbial consortium favors detoxification of the dye and textile effluents. PMID:26086710

Adsorptive amputation of hazardous azo dye Congo red from wastewater: a critical review.

PubMed

Raval, Nirav P; Shah, Prapti U; Shah, Nisha K

2016-08-01

Increasing amount of dyes in an ecosystem has propelled the search of various methods for dye removal. Amongst all the methods, adsorption occupies a prominent place in dye removal. Keeping this in mind, many adsorbents used for the removal of hazardous anionic azo dye Congo red (CR) from aqueous medium were reviewed by the authors. The main objectives behind this review article are to assemble the information on scattered adsorbents and enlighten the wide range of potentially effective adsorbents for CR removal. Thus, CR sorption by various adsorbents such as activated carbon, non-conventional low-cost materials, nanomaterials, composites and nanocomposites are surveyed and critically reviewed as well as their sorption capacities are also compared. This review also explores the grey areas of the adsorption performance of various adsorbents with reference to the effects of pH, contact time, initial dye concentration and adsorbent dosage. The equilibrium adsorption isotherm, kinetic and thermodynamic data of different adsorbents used for CR removal were also analysed. It is evident from a literature survey of more than 290 published papers that nanoparticle and nanocomposite adsorbents have demonstrated outstanding adsorption capabilities for CR. Graphical abstract ᅟ.

Optical coherence tomography using images of hair structure and dyes penetrating into the hair.

PubMed

Tsugita, Tetsuya; Iwai, Toshiaki

2014-11-01

Hair dyes are commonly evaluated by the appearance of the hair after dyeing. However, this approach cannot simultaneously assess how deep the dye has penetrated into hair. For simultaneous assessment of the appearance and the interior of hair, we developed a visible-range red, green, and blue (RGB) (three primary colors)-optical coherence tomography (OCT) using an RGB LED light source. We then evaluated a phantom model based on the assumption that the sample's absorbability in the vertical direction affects the tomographic imaging. Consistent with theory, our device showed higher resolution than conventional OCT with far-red light. In the experiment on the phantom model, we confirmed that the tomographic imaging is affected by absorbability unique to the sample. Furthermore, we verified that permeability can be estimated from this tomographic image. We also identified for the first time the relationship between penetration of the dye into hair and characteristics of wavelength by tomographic imaging of dyed hair. We successfully simultaneously assessed the appearance of dyed hair and inward penetration of the dye without preparing hair sections. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Adsorption of C.I. Natural Red 4 onto Spongin Skeleton of Marine Demosponge

PubMed Central

Norman, Małgorzata; Bartczak, Przemysław; Zdarta, Jakub; Tylus, Włodzimierz; Szatkowski, Tomasz; Stelling, Allison L.; Ehrlich, Hermann; Jesionowski, Teofil

2014-01-01

C.I. Natural Red 4 dye, also known as carmine or cochineal, was adsorbed onto the surface of spongin-based fibrous skeleton of Hippospongia communis marine demosponge for the first time. The influence of the initial concentration of dye, the contact time, and the pH of the solution on the adsorption process was investigated. The results presented here confirm the effectiveness of the proposed method for developing a novel dye/biopolymer hybrid material. The kinetics of the adsorption of carmine onto a marine sponge were also determined. The experimental data correspond directly to a pseudo-second-order model for adsorption kinetics (r2 = 0.979–0.999). The hybrid product was subjected to various types of analysis (FT-IR, Raman, 13C CP/MAS NMR, XPS) to investigate the nature of the interactions between the spongin (adsorbent) and the dye (the adsorbate). The dominant interactions between the dye and spongin were found to be hydrogen bonds and electrostatic effects. Combining the dye with a spongin support resulted with a novel hybrid material that is potentially attractive for bioactive applications and drug delivery systems. PMID:28787926

Assessment of molecularly imprinted polymers (MIPs) in the preconcentration of disperse red 73 dye prior to photoelectrocatalytic treatment.

PubMed

Franco, Jefferson Honorio; Aissa, Alejandra Ben; Bessegato, Guilherme Garcia; Fajardo, Laura Martinez; Zanoni, Maria Valnice Boldrin; Pividori, María Isabel; Del Pilar Taboada Sotomayor, Maria

2017-02-01

Magnetic molecularly imprinted polymers (MMIPs) have become a research hotspot due to their two important characteristics: target recognition and magnetic separation. This paper presents the preparation, characterization, and optimization of an MMIP for the preconcentration of disperse red 73 dye (DR73) and its subsequent efficient degradation by photoelectrocatalytic treatment. The MMIPs were characterized by scanning electron microscopy (SEM), which revealed homogeneous distribution of the particles. Excellent encapsulation of magnetite was confirmed by transmission electron microscopy (TEM). A study of dye binding showed that the dye was retained more selectively in the MIP, compared to the NIP. The release of DR73 from the imprinted polymers into methanol and acetic acid was analyzed by UV-Vis spectrophotometry. The extracts showed higher absorbance values for MMIP, compared to MNIP, confirming greater adsorption of dye in the MMIP material. The extracts were then subjected to photoelectrocatalytic treatment. LC-MS/MS analysis following this treatment showed that the dye was almost completely degraded. Hence, the combination of MMIP extraction and photoelectrocatalysis offers an alternative way of selectively removing an organic contaminant, prior to proceeding with its complete degradation.

Evaluation of the chitin-binding dye Congo red as a selection agent for the isolation, classification, and enumeration of ascomycete yeasts.

PubMed

Linder, Tomas

2018-05-01

Thirty-nine strains of ascomycete yeasts representing 35 species and 33 genera were tested for their ability to grow on solid agar medium containing increasing concentrations of the chitin-binding dye Congo red. Six strains were classified as hypersensitive (weak or no growth at 10 mg/l Congo red), five were moderately sensitive (weak or no growth at 50 mg/l), three were moderately tolerant (weak or no growth at 100 mg/l), while the remaining 25 strains were classified as resistant (robust growth at ≥ 100 mg/l) with 20 of these strains classified as hyper-resistant (robust growth at 200 mg/l). Congo red growth phenotypes were consistent within some families but not others. The frequency of Congo red resistance among ascomycete yeasts was deemed too high for the practical use of Congo red as a selection agent for targeted isolation, but can be useful for identification and enumeration of yeasts.

Ultrasonic-assisted dyeing of Nylon-6 nanofibers.

PubMed

Jatoi, Abdul Wahab; Ahmed, Farooq; Khatri, Muzamil; Tanwari, Anwaruddin; Khatri, Zeeshan; Lee, Hoik; Kim, Ick Soo

2017-11-01

We first time report ultrasonic dyeing of the Nylon 6 nanofibers with two disperse dyes CI Disperse blue 56 and CI Disperse Red 167:1 by utilising ultrasonic energy during dyeing process. The Nylon 6 nanofibers were fabricated via electrospinning and dyed via batchwise method with and without sonication. Results revealed that ultrasonic dyeing produce higher color yield (K/S values) and substantially reduces dyeing time from 60min for conventional dyeing to 30min can be attributed to breakage of dye aggregate, transient cavitation near nanofiber surface and mass transfer within/between nanofibers. Color fastness results exhibited good to very good dye fixation. SEM images exhibit insignificant effect of sonication on morphology of the nanofibers. Our research results demonstrate ultrasonic dyeing as a better dyeing technique for Nylon 6 nanofibers with higher color yield and substantially reduced dyeing time. Copyright © 2017 Elsevier B.V. All rights reserved.

Enzymatic reduction of azo and indigoid compounds.

PubMed

Pricelius, S; Held, C; Murkovic, M; Bozic, M; Kokol, V; Cavaco-Paulo, A; Guebitz, G M

2007-11-01

A customer- and environment-friendly method for the decolorization azo dyes was developed. Azoreductases could be used both to bleach hair dyed with azo dyes and to reduce dyes in vat dyeing of textiles. A new reduced nicotinamide adenine dinucleotide-dependent azoreductase of Bacillus cereus, which showed high potential for reduction of these dyes, was purified using a combination of ammonium sulfate precipitation and chromatography and had a molecular mass of 21.5 kDa. The optimum pH of the azoreductase depended on the substrate and was within the range of pH 6 to 7, while the maximum temperature was reached at 40 degrees C. Oxygen was shown to be an alternative electron acceptor to azo compounds and must therefore be excluded during enzymatic dye reduction. Biotransformation of the azo dyes Flame Orange and Ruby Red was studied in more detail using UV-visible spectroscopy, high-performance liquid chromatography, and mass spectrometry (MS). Reduction of the azo bonds leads to cleavage of the dyes resulting in the cleavage product 2-amino-1,3 dimethylimidazolium and N approximately 1 approximately ,N approximately 1 approximately -dimethyl-1,4-benzenediamine for Ruby Red, while only the first was detected for Flame Orange because of MS instability of the expected 1,4-benzenediamine. The azoreductase was also found to reduce vat dyes like Indigo Carmine (C.I. Acid Blue 74). Hydrogen peroxide (H(2)O(2)) as an oxidizing agent was used to reoxidize the dye into the initial form. The reduction and oxidation mechanism of Indigo Carmine was studied using UV-visible spectroscopy.

Artificial neural network (ANN) method for modeling of sunset yellow dye adsorption using zinc oxide nanorods loaded on activated carbon: Kinetic and isotherm study.

PubMed

Maghsoudi, M; Ghaedi, M; Zinali, A; Ghaedi, A M; Habibi, M H

2015-01-05

In this research, ZnO nanoparticle loaded on activated carbon (ZnO-NPs-AC) was synthesized simply by a low cost and nontoxic procedure. The characterization and identification have been completed by different techniques such as SEM and XRD analysis. A three layer artificial neural network (ANN) model is applicable for accurate prediction of dye removal percentage from aqueous solution by ZnO-NRs-AC following conduction of 270 experimental data. The network was trained using the obtained experimental data at optimum pH with different ZnO-NRs-AC amount (0.005-0.015 g) and 5-40 mg/L of sunset yellow dye over contact time of 0.5-30 min. The ANN model was applied for prediction of the removal percentage of present systems with Levenberg-Marquardt algorithm (LMA), a linear transfer function (purelin) at output layer and a tangent sigmoid transfer function (tansig) in the hidden layer with 6 neurons. The minimum mean squared error (MSE) of 0.0008 and coefficient of determination (R(2)) of 0.998 were found for prediction and modeling of SY removal. The influence of parameters including adsorbent amount, initial dye concentration, pH and contact time on sunset yellow (SY) removal percentage were investigated and optimal experimental conditions were ascertained. Optimal conditions were set as follows: pH, 2.0; 10 min contact time; an adsorbent dose of 0.015 g. Equilibrium data fitted truly with the Langmuir model with maximum adsorption capacity of 142.85 mg/g for 0.005 g adsorbent. The adsorption of sunset yellow followed the pseudo-second-order rate equation. Copyright © 2014 Elsevier B.V. All rights reserved.

Artificial neural network (ANN) method for modeling of sunset yellow dye adsorption using zinc oxide nanorods loaded on activated carbon: Kinetic and isotherm study

NASA Astrophysics Data System (ADS)

Maghsoudi, M.; Ghaedi, M.; Zinali, A.; Ghaedi, A. M.; Habibi, M. H.

2015-01-01

In this research, ZnO nanoparticle loaded on activated carbon (ZnO-NPs-AC) was synthesized simply by a low cost and nontoxic procedure. The characterization and identification have been completed by different techniques such as SEM and XRD analysis. A three layer artificial neural network (ANN) model is applicable for accurate prediction of dye removal percentage from aqueous solution by ZnO-NRs-AC following conduction of 270 experimental data. The network was trained using the obtained experimental data at optimum pH with different ZnO-NRs-AC amount (0.005-0.015 g) and 5-40 mg/L of sunset yellow dye over contact time of 0.5-30 min. The ANN model was applied for prediction of the removal percentage of present systems with Levenberg-Marquardt algorithm (LMA), a linear transfer function (purelin) at output layer and a tangent sigmoid transfer function (tansig) in the hidden layer with 6 neurons. The minimum mean squared error (MSE) of 0.0008 and coefficient of determination (R2) of 0.998 were found for prediction and modeling of SY removal. The influence of parameters including adsorbent amount, initial dye concentration, pH and contact time on sunset yellow (SY) removal percentage were investigated and optimal experimental conditions were ascertained. Optimal conditions were set as follows: pH, 2.0; 10 min contact time; an adsorbent dose of 0.015 g. Equilibrium data fitted truly with the Langmuir model with maximum adsorption capacity of 142.85 mg/g for 0.005 g adsorbent. The adsorption of sunset yellow followed the pseudo-second-order rate equation.

Rapid and high-capacity ultrasonic assisted adsorption of ternary toxic anionic dyes onto MOF-5-activated carbon: Artificial neural networks, partial least squares, desirability function and isotherm and kinetic study.

PubMed

Askari, Hanieh; Ghaedi, Mehrorang; Dashtian, Kheibar; Azghandi, Mohammad Hossein Ahmadi

2017-07-01

The present paper focused on the ultrasonic assisted simultaneous removal of fast green (FG), eosin Y (EY) and quinine yellow (QY) from aqueous media following using MOF-5 as a metal organic framework and activated carbon hybrid (AC-MOF-5). The structure and morphology of AC-MOF-5 was identified by SEM, FTIR and XRD analysis. The interactive and main effects of variables such as pH, initial dyes concentration (mgL -1 ), adsorbent dosage (mg) and sonication time (min) on removal percentage were studied by central composite design (CCD), subsequent desirability function (DF) permit to achieved real variable experimental condition. Optimized values were found 7.06, 5.68, 7.59 and 5.04mgL -1 , 0.02g and 2.55min for pH, FG, EY and QY concentration, adsorbent dosage and sonication time, respectively. Under this conditions removal percentage were obtained 98.1%, 98.1% and 91.91% for FG, EY and QY, respectively. Two models, namely partial least squares (PLS) and multi-layer artificial neural network (ANN) model were used for building up to construct an empirical model to predict the dyes under study removal behavior. The obtained results show that ANN and PLS model is a powerful tool for prediction of under-study dyes adsorption by AC-MOF-5. The evaluation and estimation of equilibrium data from traditional isotherm models display that the Langmuir model indicated the best fit to the equilibrium data with maximum adsorption capacity of 21.230, 20.242 and 18.621mgg -1 , for FG, EY and QY, respectively, while the adsorption rate efficiently follows the pseudo-second-order model. Copyright © 2016 Elsevier B.V. All rights reserved.

Biosorption of food dyes onto Spirulina platensis nanoparticles: equilibrium isotherm and thermodynamic analysis.

PubMed

Dotto, G L; Lima, E C; Pinto, L A A

2012-01-01

The biosorption of food dyes FD&C red no. 40 and acid blue 9 onto Spirulina platensis nanoparticles was studied at different conditions of pH and temperature. Four isotherm models were used to evaluate the biosorption equilibrium and the thermodynamic parameters were estimated. Infra red analysis (FT-IR) and energy dispersive X-ray spectroscopy (EDS) were used to verify the biosorption behavior. The maximum biosorption capacities of FD&C red no. 40 and acid blue 9 were found at pH 4 and 298 K, and the values were 468.7 mg g(-1) and 1619.4 mg g(-1), respectively. The Sips model was more adequate to fit the equilibrium experimental data (R2>0.99 and ARE<5%). Thermodynamic study showed that the biosorption was exothermic, spontaneous and favorable. FT-IR and EDS analysis suggested that at pH 4 and 298 K, the biosorption of both dyes onto nanoparticles occurred by chemisorption. Copyright © 2011 Elsevier Ltd. All rights reserved.

Distinct Interfacial Fluorescence in Oil-in-Water Emulsions via Exciton Migration of Conjugated Polymers.

PubMed

Koo, Byungjin; Swager, Timothy M

2017-09-01

Commercial dyes are extensively utilized to stain specific phases for the visualization applications in emulsions and bioimaging. In general, dyes emit only one specific fluorescence signal and thus, in order to stain various phases and/or interfaces, one needs to incorporate multiple dyes and carefully consider their compatibility to avoid undesirable interactions with each other and with the components in the system. Herein, surfactant-type, perylene-endcapped fluorescent conjugated polymers that exhibit two different emissions are reported, which are cyan in water and red at oil-water interfaces. The interfacially distinct red emission results from enhanced exciton migration from the higher-bandgap polymer backbone to the lower-bandgap perylene endgroup. The confocal microscopy images exhibit the localized red emission exclusively from the circumference of oil droplets. This exciton migration and dual fluorescence of the polymers in different physical environments can provide a new concept of visualization methods in many amphiphilic colloidal systems and bioimaging. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Column performance of carbon nanotube packed bed for methylene blue and orange red dye removal from waste water

NASA Astrophysics Data System (ADS)

Gill, G. K.; Mubarak, N. M.; Nizamuddin, S.; Al-Salim, H. S.; Sahu, J. N.

2017-06-01

Environmental issues have always been a major issue among human kind for the past decades. As the time passes by, the technology field has grown and has helped a lot in order to reduce these environmental issues. Industries such as metal plating facilities, mining operations and batteries production are a few examples that involves in the environmental issues. Carbon nanotube is proven to possess excellent adsorption capacity for the removal of methylene blue and orange red dyes. The effect of process parameters such as pH and contact time was investigated The results revealed that optimized conditions for the highest removal for methylene blue (MB) (97%) and orange red (94%) are at pH 10, CNTs dosage of 1 grams, and 15 minutes for each dyes removal respectively. The equilibrium adsorption data obtained was best fit to Freundlich model, while kinetic data can be characterized by the pseudo second-order rate kinetics.

Understanding the degradation of Congo red and bacterial diversity in an air-cathode microbial fuel cell being evaluated for simultaneous azo dye removal from wastewater and bioelectricity generation.

PubMed

Sun, Jian; Li, Youming; Hu, Yongyou; Hou, Bin; Zhang, Yaping; Li, Sizhe

2013-04-01

We investigated the mechanism of Congo red degradation and bacterial diversity in a single-chambered microbial fuel cell (MFC) incorporating a microfiltration membrane and air-cathode. The MFC was operated continuously for more than 4 months using a mixture of Congo red and glucose as fuel. We demonstrated that the Congo red azo bonds were reduced at the anode to form aromatic amines. This is consistent with the known mechanism of anaerobic biodegradation of azo dyes. The MFC developed a less dense biofilm at the anode in the presence of Congo red compared to its absence indicating that Congo red degradation negatively affected biofilm formation. Denaturing gradient gel electrophoresis and direct 16S ribosomal DNA gene nucleotide sequencing revealed that the microbial communities differed depending on whether Congo red was present in the MFC. Geobacter-like species known to generate electricity were detected in the presence or absence of Congo red. In contrast, Azospirillum, Methylobacterium, Rhodobacter, Desulfovibrio, Trichococcus, and Bacteroides species were only detected in its presence. These species were most likely responsible for degrading Congo red.

Decolorizing of azo dye Reactive red 24 aqueous solution using exfoliated graphite and H2O2 under ultrasound irradiation.

PubMed

Li, Mei; Li, Ji-Tai; Sun, Han-Wen

2008-07-01

At its natural pH (6.95), the decolorization of Reactive red 24 in ultrasound, ultrasound/H2O2, exfoliated graphite, ultrasound/exfoliated graphite, exfoliated graphite/H2O2 and ultrasound/exfoliated graphite/H2O2 systems were compared. An enhancement was observed for the decolorization in ultrasound/exfoliated graphite/H2O2 system. The effect of solution pH, H2O2 and exfoliated graphite dosages, and temperature on the decolorization of Reactive red 24 was investigated. The sonochemical treatment in combination with exfoliated graphite/H2O2 showed a synergistic effect for the decolorization of Reactive red 24. The results indicated that under proper conditions, there was a possibility to remove Reactive red 24 very efficient from aqueous solution. The decolorization of other azo dyes (Reactive red 2, Methyl orange, Acid red 1, Acid red 73, Acid red 249, Acid orange 7, Acid blue 113, Acid brown 75, Acid green 20, Acid yellow 42, Acid mordant brown 33, Acid mordant yellow 10 and Direct green 1) was also investigated, at their natural pH.

Effect of methyl red dye on dielectric and conductivity properties of PEO/CdCl{sub 2} electrolytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamath, Archana; Devendrappa, H., E-mail: dehu2010@gmail.com

2016-05-06

In this report the conductivity and dielectric properties of polyethylene oxide-cadmium chloride (PEO/CdCl{sub 2}) polymer electrolyte films doped with an azo dye methyl red (MR) are discussed. The films were prepared by solution casting technique at different concentrations of the dye in PEO/CdCl{sub 2} electrolyte. The thermal behavior, chemical interaction of the dye with the electrolyte and surface morphology were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) respectively. The conductivity and dielectric properties were measured as a function of composition and temperature using complex impedance spectroscopy. The temperature dependent electrical conductivitymore » of the films exhibited Arrhenius type behavior. Conductivity and dielectric results also signify the enhancement in the amorphous phase of the polymer electrolyte dye systems. The value of highest conductivity observed is 1.21x10{sup −4} at 343K and the conductivity of the film was enhanced by a three orders of magnitude.« less

A simple system for the identification of fluorescent dyes capable of reporting differences in secondary structure and hydrophobicity among amyloidogenic protein oligomers

NASA Astrophysics Data System (ADS)

Yates, Emma

2012-02-01

Thioflavin T and Congo Red are fluorescent dyes that are commonly used to identify the presence of amyloid structures, ordered protein aggregates. Despite the ubiquity of their use, little is known about their mechanism of interaction with amyloid fibrils, or whether other dyes, whose photophysics indicate that they may be more responsive to differences in macromolecular secondary structure and hydrophobicity, would be better suited to the identification of pathologically relevant oligomeric species in amyloid diseases. In order to systematically address this question, we have designed a strategy that discretely introduces differences in secondary structure and hydrophobicity amidst otherwise identical polyamino acids. This strategy will enable us to quantify and compare the affinities of Thioflavin T, Congo Red, and other, incompletely explored, fluorescent dyes for different secondary structural elements and hydrophobic motifs. With this information, we will identify dyes that give the most robust and quantitative information about structural differences among the complex population of oligomeric species present along an aggregation pathway between soluble monomers and amyloid fibrils, and correlate the resulting structural information with differential oligomeric toxicity.

Utilization of a new optical sensor unit to monitor the electrochemical elimination of selected dyes in water

NASA Astrophysics Data System (ADS)

Valica, M.; Černá, T.; Hostin, S.

2017-10-01

This paper presents results obtained by developed optical sensor, which consist from multi-wavelength LED light source and two photodetectors capable of measuring the change in optical signal along two different optical paths (absorbance and reflectance measurements). Arduino microcomputer was used for light source management and optical signal data measuring and recording. Analytical validation of developed optical sensor is presented in this paper. The performance of the system has been tested with varying water solution of dyes (malachite green, methyl orange, trypan red). These results show strong correlations between the optical signal response and colour change from the dyes. Sensor was used for continual in-situ monitoring of electrochemical elimination of selected dyes (current density 15.7 mA cm-2, electrolyte volume 4 L and NaCl concentration 2 g L-1). Maximum decolorization level varies with each dye. For malachite green was obtain 92,7 % decolorization (25 min); methyl orange 90,8% (8,5 min) and trypan red 84,7% decolorization after 33 min of electrochemical treatment.

Green synthesis of palm oil mill effluent-based graphenic adsorbent for the treatment of dye-contaminated wastewater.

PubMed

Teow, Yeit Haan; Nordin, Nadzirah Ilyiani; Mohammad, Abdul Wahab

2018-05-12

Textile wastewater contains methylene blue (MB), a major coloring agent in textile industry. Activated carbon (AC) is the most widely used adsorbent in removing dyes from industrial wastewater. However, high production cost of AC is the major obstacle for its wide application in dye wastewater treatment. In this study, a sustainable approach in synthesizing graphenic adsorbent from palm oil mill effluent (POME), a potential carbonaceous source, has been explored. This new development in adsorption technique is considered as green synthesis as it does not require any binder during the synthesis process, and at the same time, it helps to solve the bottleneck of palm oil industry as POME is the main cause contributed to Malaysia's water pollution problem. The synthesized GSC was characterized through XRD, FESEM, and EDX. The adsorption performance of the synthesized GSC was evaluated by adsorption of MB. The effect of initial concentration of synthetic MB solution (1-20 mg/L) and weight of GSC (5-20 g) were investigated. A remarkable change in color of synthetic MB solution from blue to crystal clear was observed at the end of adsorption study. High efficiency of the synthesized GSC for dye-contaminated wastewater treatment is concluded.

Antimicrobial evaluation of red, phytoalexin-rich sorghum food biocolorant

PubMed Central

den Besten, Heidy M. W.; Kayodé, A. P. Polycarpe; Fogliano, Vincenzo; Linnemann, Anita R.

2018-01-01

Sorghum (Sorghum bicolor) extract is traditionally used as red biocolorant in West Africa to colour foods, among which wagashi, a soft cheese. This biocolorant is a source of the phytoalexin apigeninidin and phenolic acids, and users claim that it has preservative effects next to its colouring properties. If such a claim can be scientifically substantiated, it adds a valuable functional property to this natural red colorant, thereby increasing its potential applications in the food industry. Hence, the present study evaluated the antimicrobial properties of dye sorghum extracts using challenge tests in broth and wagashi as a model of a popular food application. The alkaline extract and hot aqueous extract were used for dyeing wagashi by 87.7% and 12.3% of the traders, respectively. The dyeing procedure is perceived as a preservation strategy, and is also a means to maximise the revenues. However, results demonstrated that the application of sorghum biocolorant on wagashi had no inhibitory effect on the growth of fungi (Penicillium chrysogenum, Cladosporium macrocarpum) and Escherichia coli O157:H7. Furthermore, sorghum biocolorant in broth had no effect on growth of Listeria monocytogenes and Escherichia coli O157:H7. Consequently, the commonly used extracts for colouring soft West-African cheese did not show a preservative effect. In addition, dyeing did not affect the physico-chemical properties of wagashi. Still, the red colour hampered visual detection of microbial growth, thus clarifying the preservative effect reported by users. PMID:29561885

Antimicrobial evaluation of red, phytoalexin-rich sorghum food biocolorant.

PubMed

Akogou, Folachodé U G; Besten, Heidy M W den; Kayodé, A P Polycarpe; Fogliano, Vincenzo; Linnemann, Anita R

2018-01-01

Sorghum (Sorghum bicolor) extract is traditionally used as red biocolorant in West Africa to colour foods, among which wagashi, a soft cheese. This biocolorant is a source of the phytoalexin apigeninidin and phenolic acids, and users claim that it has preservative effects next to its colouring properties. If such a claim can be scientifically substantiated, it adds a valuable functional property to this natural red colorant, thereby increasing its potential applications in the food industry. Hence, the present study evaluated the antimicrobial properties of dye sorghum extracts using challenge tests in broth and wagashi as a model of a popular food application. The alkaline extract and hot aqueous extract were used for dyeing wagashi by 87.7% and 12.3% of the traders, respectively. The dyeing procedure is perceived as a preservation strategy, and is also a means to maximise the revenues. However, results demonstrated that the application of sorghum biocolorant on wagashi had no inhibitory effect on the growth of fungi (Penicillium chrysogenum, Cladosporium macrocarpum) and Escherichia coli O157:H7. Furthermore, sorghum biocolorant in broth had no effect on growth of Listeria monocytogenes and Escherichia coli O157:H7. Consequently, the commonly used extracts for colouring soft West-African cheese did not show a preservative effect. In addition, dyeing did not affect the physico-chemical properties of wagashi. Still, the red colour hampered visual detection of microbial growth, thus clarifying the preservative effect reported by users.

Solvent-free fluidic organic dye lasers.

PubMed

Choi, Eun Young; Mager, Loic; Cham, Tran Thi; Dorkenoo, Kokou D; Fort, Alain; Wu, Jeong Weon; Barsella, Alberto; Ribierre, Jean-Charles

2013-05-06

We report on the demonstration of liquid organic dye lasers based on 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, doped with green- and red-emitting laser dyes. Both waveguide and Fabry-Perot type microcavity fluidic organic dye lasers were prepared by capillary action under solvent-free conditions. Cascade Förster-type energy transfer processes from liquid carbazole to laser dyes were employed to achieve color-variable amplified spontaneous emission and lasing. Overall, this study provides the first step towards the development of solvent-free fluidic organic semiconducting lasers and demonstrates a new kind of optoelectronic applications for liquid organic semiconductors.

Panel Discussion: Red Lake Forestry Greenhouse Operations

Treesearch

Gloria Whitefeather-Spears

2006-01-01

The tribal lands of the Red Lake Band of the Chippewa Indians are comprised of four districts in north central Minnesota. The Diminished Reservation, where most tribal members live and work, is approximately 532,000 ac (215,290 ha) in size and includes forests, wetlands, and grasslands. An additional 262,000 ac (106,030 ha) comprise ceded lands, called the Northwest...

Efficient azo dye decolorization in a continuous stirred tank reactor (CSTR) with built-in bioelectrochemical system.

PubMed

Cui, Min-Hua; Cui, Dan; Gao, Lei; Cheng, Hao-Yi; Wang, Ai-Jie

2016-10-01

A continuous stirred tank reactor with built-in bioelectrochemical system (CSTR-BES) was developed for azo dye Alizarin Yellow R (AYR) containing wastewater treatment. The decolorization efficiency (DE) of the CSTR-BES was 97.04±0.06% for 7h with sludge concentration of 3000mg/L and initial AYR concentration of 100mg/L, which was superior to that of the sole CSTR mode (open circuit: 54.87±4.34%) and the sole BES mode (without sludge addition: 91.37±0.44%). The effects of sludge concentration and sodium acetate (NaAc) concentration on azo dye decolorization were investigated. The highest DE of CSTR-BES for 4h was 87.66±2.93% with sludge concentration of 12,000mg/L, NaAc concentration of 2000mg/L and initial AYR concentration of 100mg/L. The results in this study indicated that CSTR-BES could be a practical strategy for upgrading conventional anaerobic facilities against refractory wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optical Sensor based Chemical Modification as a Porous Cellulose Acetate Film and Its Application for Ethanol Sensor

NASA Astrophysics Data System (ADS)

Mulijani, S.; Iswantini, D.; Wicaksono, R.; Notriawan, D.

2018-03-01

A new approach to design and construction of an optical ethanol sensor has been developed by immobilizing a direct dye at a porous cellulosic polymer fllm. This sensor was fabricated by binding Nile Red to a cellulose acetate membrane that had previously been subjected to an exhaustive base hydrolysis. The prepared optical ethanol sensor was enhanced by adding pluronic as a porogen in the membrane. The addition of pluronic surfactant into cellulose acetate membrane increased the hydrophilic and porous properties of membrane. Advantageous features of the design include simple and easy of fabrication. Variable affecting sensor performance of dye concentration have been fully evaluated and optimized. The rapid response results from the porous structure of the polymeric support, which minimizes barriers to mass transport. Signal of optical sensor based on reaction of dye nile red over the membrane with ethanol and will produce the purple colored product. Result was obtained that maximum intensity of dye nile red reacted with alcohol is at 630-640 nm. Linear regression equation (r2), limit of detection, and limit of quantitation of membrane with 2% dye was 0.9625, 0.29%, and 0.97%. Performance of optical sensor was also evaluated through methanol, ethanol and propanol. This study was purposed to measure the polarity and selectivity of optic sensor toward the alcohol derivatives. Fluorescence intensity of optic sensor membrane for methanol 5%, ethanol 5% and propanol 5% was 15113.56, 16573.75 and 18495.97 respectively.

Quantitative Determination of Four Azo Dyes in Rat Plasma with Solid-Phase Extraction and UFLC-MS-MS Analysis: Application to a Pharmacokinetic Study.

PubMed

Zhu, Hao; Huang, Changshun; Chen, Yijun; Lu, Zihui; Zhou, Haidong; Chen, Chunru; Wu, Jin; Chen, Xiaohong; Jin, Micong

2016-06-05

A rapid and sensitive ultra-fast liquid chromatography tandem mass spectrometry method, followed by simple protein precipitation and solid-phase extraction, has been developed and validated for the quantitative determination of four azo dyes (Para red, Solvent yellow 2, Solvent red 1 and Sudan red 7B) in rat plasma using D 5 -Sudan I as the internal standard. The optimal separation was accomplished on an Agilent Eclipse Plus C18 column (100 × 2.1 mm, 1.8 μm) with gradient elution using the mobile phase including acetonitrile and water (containing 0.1% formic acid). The flow rate was 0.45 mL/min. The detection was conducted by means of electrospray ionization mass spectrometry in positive ion mode with multiple reaction monitoring. The calibration curves showed good linearity, with correlation coefficients >0.998 for all of the analytes within the concentration range. The lower limits of quantification (LLOQs) of Para red, Solvent yellow 2, Solvent red 1 and Sudan red 7B in rat plasma were 1.0, 0.1, 0.1 and 0.1 μg/L, respectively. The intra- and interday relative standard deviations were ≤9.6 and ≤12.4%, respectively, and the accuracy was in the range of -5.8 to -9.5%. The average recoveries were between 81.49 and 118.65%, and the matrix effects were satisfactory in the biological matrices. The fully validated method has been successfully applied in measuring levels of the four azo dyes in rat plasma following oral administration of 20.0 mg/kg of analytes in rats, which was suitable for the pharmacokinetic studies of the azo dyes. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Accuracy of acromioclavicular joint injections.

PubMed

Wasserman, Bradley R; Pettrone, Sarah; Jazrawi, Laith M; Zuckerman, Joseph D; Rokito, Andrew S

2013-01-01

Injection to the acromioclavicular (AC) joint can be both diagnostic and therapeutic. The purpose of this study was to evaluate the accuracy of in vivo AC joint injections. Case series; Level of evidence, 4. Thirty patients with pain localized to the AC joint were injected with 1 mL of 1% lidocaine and 0.5 mL of radiographic contrast material (Isovue). Radiographs of the AC joint were taken after the injection. Each radiograph was reviewed by a musculoskeletal radiologist and graded as intra-articular, extra-articular, or partially intra-articular. Of the 30 injections performed, 13 (43.3%) were intra-articular, 7 (23.3%) were partially articular, and 10 (33.3%) were extra-articular. When the intra-articular and the partially articular groups were combined, 20 patients (66.7%) had some contrast dye in the AC joint. This study demonstrates that despite the relatively superficial location of the AC joint, the clinical accuracy of AC joint injections remains relatively low.

Tuning the band gap of TiO2 by tungsten doping for efficient UV and visible photodegradation of Congo red dye.

PubMed

Ullah, Irfan; Haider, Ali; Khalid, Nasir; Ali, Saqib; Ahmed, Sajjad; Khan, Yaqoob; Ahmed, Nisar; Zubair, Muhammad

2018-06-13

Tungsten-doped TiO 2 (W@TiO 2 ) nanoparticles, with different percentages of atomic tungsten dopant levels (range of 0 to 6 mol%) have been synthesized by the sol-gel method and characterized by UV-Visible spectroscopy, XRD, SEM, EDX, ICP-OES and XPS analysis. By means of UV-Vis spectroscopy, it has been observed that with 6 mol% tungsten doping the wavelength range of excitation of TiO 2 has extended to the visible portion of spectrum. Therefore, we evaluated the photocatalytic activity of W@TiO 2 catalysts for the degradation of Congo red dye under varying experimental parameters such as dopant concentration, catalyst dosage, dye concentrations and pH. Moreover, 6 mol% W@TiO 2 catalyst was deposited on a glass substrate to form thin film using spin coating technique in order to make the photocatalyst effortlessly reusable with approximately same efficiency. The results compared with standard titania, Degussa P25 both in UV- and visible light, suggest that 6 mol% W@TiO 2 can be a cost-effective choice for visible light induced photocatalytic degradation of Congo red dye. Copyright © 2018 Elsevier B.V. All rights reserved.

Theoretical Study of Effect of Introducing π-Conjugation on Efficiency of Dye-Sensitized Solar Cell.

PubMed

Lee, Geon Hyeong; Kim, Young Sik

2018-09-01

In this study, phenoxazine (PXZ)-based dye sensitizers with triphenylamine (TPA) as a dual-electron donor and thiophen and benzothiadiazole (BTD) or 4,7-diethynylbenzo[c][1,2,5]thiadiazole (DEBT) as an electron acceptor (dye1, dye2, and dye3) were designed and investigated. dye3 can significantly stabilize the lowest unoccupied molecular orbital (LUMO) energy level of an organic dye. We used density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations to better understand the factors responsible for the photovoltaic performance. The absorption spectrum of the dyes showed different forms because of the different energy levels of the molecular orbital (MO) of each dye and the intramolecular energy transfer (EnT). Among the three dyes, dye3 showed greater red-shift, broader absorption spectra, and higher molar extinction coefficient. These results indicate that adding a withdrawing unit and π-conjugation to a dye can result in good photovoltaic properties for dye-sensitized solar cells (DSSCs).

Congo red agar, a differential medium for Aeromonas salmonicida, detects the presence of the cell surface protein array involved in virulence.

PubMed Central

Ishiguro, E E; Ainsworth, T; Trust, T J; Kay, W W

1985-01-01

Strains of the fish pathogen Aeromonas salmonicida which possess the cell surface protein array known as the A-layer (A+) involved in virulence formed deep red colonies on tryptic soy agar containing 30 micrograms of Congo red per ml. These were readily distinguished from colorless or light orange colonies of avirulent mutants lacking A-layer (A-). The utility of Congo red agar for quantifying A+ and A- cells in the routine assessment of culture virulence was demonstrated. Intact A+ cells adsorbed Congo red, whereas A- mutants did not bind Congo red unless first permeabilized with EDTA. The dye-binding component of A+ cells was shown to be the 50,000-Mr A-protein component of the surface array. Purified A-protein avidly bound Congo red at a dye-to-protein molar ratio of about 30 by a nonspecific hydrophobic mechanism enhanced by high salt concentrations. Neither A+ nor A- cells adsorbed to Congo red-Sepharose columns at low salt concentrations. On the other hand, A+ (but not A-) cells were avidly bound at high salt concentrations. Images PMID:3934141

Adsorption of Methyl Red by water-hyacinth (Eichornia crassipes) biomass.

PubMed

Tarawou, Temi; Horsfall, Michael; Vicente, José L

2007-09-01

The surface characteristics and adsorbent properties of biomass, obtained from low-cost and environmentally problematic water hyacinth, were determined. Optimum conditions for the elimination of the industrial dye Methyl Red (1) from aqueous solution were established by means of a batch adsorption technique. The ultimate adsorption capacity of water-hyacinth biomass in terms of the elimination of 1 was calculated from a Langmuir-type isotherm as 8.85x10(-2) mol g(-1) at 30 degrees and at an optimum solution pH of 8.0. Dye elimination was found to be associated with strong electrostatic forces (physisorption), the overall process being slightly endergonic (deltaG>0). Our study shows that water hyacinth has a great potential of removing color from wastewater and other dye-polluted aquatic systems.

Thermoresponsive cellulose ether and its flocculation behavior for organic dye removal.

PubMed

Tian, Ye; Ju, Benzhi; Zhang, Shufen; Hou, Linan

2016-01-20

A thermoresponsive polymer, 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC), was prepared by grafting butyl glycidyl ether (BGE) onto hydroxyethyl cellulose (HEC). The lower critical solution temperature (LCST) and critical flocculation temperature (CFT) of HBPEC were varied by changing the molar substitution (MS) and salt concentrations. Transmission electron microscopy (TEM) images and fluorescence spectroscopy showed that HBPEC can assemble into micelles. Additionally, using Nile Red as a model dye, the performance of HBPEC for the removing Nile Red from aqueous solutions via cloud point extraction procedures was investigated in detail. The encapsulation behavior of dye in the aqueous solution of HBPEC was studied by fluorescence spectroscopy and fluorescence microscope. The experimental results indicated that 99.4% of dye was removed from the aqueous solutions, and the HBPEC was recycled and reused easily, Furthermore, the recycle efficiency (RE) and maximum loading capacity portrayed little loss with the number of cycles. Copyright © 2015 Elsevier Ltd. All rights reserved.

Toxicity of tomato red, a popular food dye blend on male albino mice.

PubMed

Sharma, Shipra; Goyal, Rajendra P; Chakravarty, Geetanjali; Sharma, Anjali

2008-06-01

Colour in food is an integral part of our culture and is also indispensable to the modern day consumer. During the past several decades, the technology of food processing has changed dramatically and the growth in the use of synthetic food colours as an individual dye or in the form of blends has increased enormously. In the present investigation, an attempt has been made to evaluate the toxic effects of a commonly used dye blend, tomato red on male Swiss albino mice. The mice were treated orally with 2 and 6g/kg body weight/day for 42 days. The present study revealed an increase in the body weight and liver weight. However, a decrease was recorded in the weights of kidneys and testes. Histopathological study revealed severe degenerative changes in the liver, kidney and testes. In conclusion, the use of the dye blend in various food items has adverse effect on the vital organs.

Removal of Direct Red 12B by garlic peel as a cheap adsorbent: Kinetics, thermodynamic and equilibrium isotherms study of removal

NASA Astrophysics Data System (ADS)

Asfaram, A.; Fathi, M. R.; Khodadoust, S.; Naraki, M.

2014-06-01

The removal of dyes from industrial waste is very important from health and hygiene point of view and for environmental protection. In this work, efficiency and performance of garlic peel (GP) adsorbent for the removal of Direct Red 12B (DR12B) from wastewater was investigated. The influence of variables including pH, concentration of the dye and amount of adsorbent, particle size, contact time and temperature on the dye removal has been investigated. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient and the equilibrium data fitted well with the Langmuir model. More than 99% removal efficiency was obtained within 25 min at adsorbent dose of 0.2 g per 50 ml for initial dye concentration of 50 mg L-1. Calculation of various thermodynamic parameters such as, Gibb's free energy, entropy and enthalpy of the on-going adsorption process indicate feasibility and endothermic nature of DR12B adsorption.

Ultra-high-performance liquid chromatography/tandem high-resolution mass spectrometry analysis of sixteen red beverages containing carminic acid: identification of degradation products by using principal component analysis/discriminant analysis.

PubMed

Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Mastroianni, Rita; Marengo, Emilio

2015-01-15

The study investigates the sunlight photodegradation process of carminic acid, a natural red colourant used in beverages. For this purpose, both carminic acid aqueous standard solutions and sixteen different commercial beverages, ten containing carminic acid and six containing E120 dye, were subjected to photoirradiation. The results show different patterns of degradation, not only between the standard solutions and the beverages, but also from beverage to beverage. Due to the different beverage recipes, unpredictable reactions take place between the dye and the other ingredients. To identify the dye degradation products in a very complex scenario, a methodology was used, based on the combined use of principal component analysis with discriminant analysis and ultra-high-performance liquid chromatography coupled with tandem high resolution mass spectrometry. The methodology is unaffected by beverage composition and allows the degradation products of carminic acid dye to be identified for each beverage. Copyright © 2014 Elsevier Ltd. All rights reserved.

Near-infrared absorption in symmetric squarylium and croconate dyes: a comparative study using symmetry-adapted cluster-configuration interaction methods.

PubMed

Prabhakar, Ch; Yesudas, K; Krishna Chaitanya, G; Sitha, Sanyasi; Bhanuprakash, K; Rao, V Jayathirtha

2005-09-29

Symmetric croconate (CR) and squarylium dyes (SQ) are well-known near-infrared (NIR) dyes and, in general, are considered to be donor-acceptor-donor type molecules. It is established in the literature that CR dyes absorb in a longer wavelength region than the corresponding SQ dyes. This has been attributed to the CR ring being a better acceptor than the SQ ring. Thus increasing the donor capacity should lead to a bathochromic shift in both SQ and CR. On the other hand, some experiments reported in the literature have revealed that increasing the conjugation in the donor part of the SQ molecule leads first to red shift, which upon a further increase of the conjugation changes to a blue shift. Hence, to understand the role of the central ring and the substitutions in the absorption of these dyes, we carried out high-level symmetry-adapted cluster-configuration interaction (SAC-CI) calculations of some substituted SQ and CR dyes and compare the absorption energy with the existing experimental data. We found that there is very good agreement. We also carried out SAC-CI calculations of some smaller model molecules, which contain the main oxyallyl substructure. We varied the geometry (angle) of the oxyallyl subgroup and the substitution in these model molecules to establish a correlation with the bathochromic shift. We found that the charge transfer is very small and does not play the key role in the red shift, but on the other hand, the perturbation of the HOMO-LUMO gap (HLG) from both the geometry and substitution seems to be responsible for this shift. We suggest as a design principle that increasing the donor capacity of the groups may not help in the red shift, but introducing groups which perturb the HLG and decrease it without changing the MO character should lead to a larger bathochromic shift.

Allergic conjunctivitis and dry eye syndrome.

PubMed

Hom, Milton M; Nguyen, Andrew L; Bielory, Leonard

2012-03-01

Allergic conjunctivitis (AC) and dry eye syndrome (DES) are 2 of the most common anterior inflammatory disorders of the ocular surface and one does not preclude the coexistence of the other. To examine the potential overlap between AC and DES as comorbidities. Using the validated questionnaire known as Subjective Evaluation of Symptom of Dryness, we studied self-reported itchiness, dryness, and redness. In an outpatient optometric setting, 689 patients treated from January 1, 2007, to January 1, 2011, were surveyed for their ocular history and categorized according to their reported level of discomfort of itchiness, dryness, and redness. Patients ranged in age from 5 to 90 years (median age, 25 years; 39.5% male; 60.5% female). In the studied 689 patients, clinically significant itchiness was found in 194 (28.2%), dry eyes in 247 (35.8%), and redness in 194 (28.2%). Symptom overlap was demonstrated in many of the patients. Of the 194 patients with itchiness, 112 (57.7%) had clinically significant dryness. In the 247 patients with dry eyes, 112 (45.3%) had clinically significant itch. Redness was apparent in 120 of the 194 patients with itch (61.9%) and 122 of the 247 patients with dryness (49.4%). Statistical analysis demonstrated that self-reported itchiness, dryness, and redness were not independent of each other (P<.001; Pearson χ(2) test). The odds of patients with "itchy eyes" also experiencing dry eyes were 2.11 times and the odds of these patients also experiencing redness were 7.34 times that of patients with nonitchy eyes. Most patients with "itchy eyes" consistent with AC also have dry eyes and redness. These results suggest that some symptomatic patients concomitantly have features of AC and DES. Copyright © 2012 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Degradation of Remazol Red in batik dye waste water by contact glow discharge electrolysis method using NaOH and NaCl electrolytes

NASA Astrophysics Data System (ADS)

Saksono, Nelson; Putri, Dita Amelia; Suminar, Dian Ratna

2017-03-01

Contact Glow Discharge Electrolysis (CGDE) method is one of Plasma Electrolysis technology which has been approved to degrade organic waste water because it is very productive in producing hydroxyl radical. This study aims to degrade Remazol Red by CGDE method and evaluate important parameters that have influent in degradation process of Remazol Red in Batik dye waste water in batch system. The kind of electrolyte (acid and base) and the addition of metal ion such as Fe2+ have affected Remazol Red degradation percentage. Ultraviolet-Visible (UV-Vis) absorption spectra were used to monitor the degradation process. The result of study showed that percentage degradation was 99.97% which obtained by using NaCl 0.02 M with addition Fe2+ 20 ppm, applied voltage 700 volt, anode depth 0.5 cm, initial concentration of Remazol Red 250 ppm and the temperature of solutions was maintained 50-60 ˚C.

Physiological and biochemical responses of Chlorella vulgaris to Congo red.

PubMed

Hernández-Zamora, Miriam; Perales-Vela, Hugo Virgilio; Flores-Ortíz, César Mateo; Cañizares-Villanueva, Rosa Olivia

2014-10-01

Extensive use of synthetic dyes in many industrial applications releases large volumes of wastewater. Wastewaters from dying industries are considered hazardous and require careful treatment prior to discharge into receiving water bodies. Dyes can affect photosynthetic activities of aquatic flora and decrease dissolved oxygen in water. The aim of this study was to evaluate the effect of Congo red on growth and metabolic activity of Chlorella vulgaris after 96h exposure. Exposure of the microalga to Congo red reduced growth rate, photosynthesis and respiration. Analysis of chlorophyll a fluorescence emission showed that the donor side of photosystem II was affected at high concentrations of Congo red. The quantum yield for electron transport (φEo), the electron transport rate (ETR) and the performance index (PI) also decreased. The reduction in the ability to absorb and use the quantum energy increased non-photochemical (NPQ) mechanisms for thermal dissipation. Overall, Congo red affects growth and metabolic activity in photosynthetic organisms in aquatic environments. Copyright © 2014 Elsevier Inc. All rights reserved.

A switchable digital microfluidic droplet dye-laser.

PubMed

Kuehne, Alexander J C; Gather, Malte C; Eydelnant, Irwin A; Yun, Seok-Hyun; Weitz, David A; Wheeler, Aaron R

2011-11-07

Digital microfluidic devices allow the manipulation of droplets between two parallel electrodes. These electrodes can act as mirrors generating a micro-cavity, which can be exploited for a droplet dye-laser. Three representative laser-dyes with emission wavelengths spanning the whole visible spectrum are chosen to show the applicability of this concept. Sub-microlitre droplets of laser-dye solution are moved in and out of a lasing site on-chip to down-convert the UV-excitation light into blue, green and red laser-pulses. This journal is © The Royal Society of Chemistry 2011

Low roll-off and high efficiency orange OLEDs using green and red dopants in an exciplex forming co-host

NASA Astrophysics Data System (ADS)

Lee, Sunghun; Kim, Kwon-Hyeon; Yoo, Seung-Jun; Park, Young-Seo; Kim, Jang-Joo

2013-09-01

We present high efficiency orange emitting OLEDs with low driving voltage and low roll-off of efficiency using an exciplex forming co-host by (1) co-doping of green and red emitting phosphorescence dyes in the host and (2) red and green phosphorescent dyes doped in the host as separate red and green emitting layers. The orange OLEDs achieved a low turn-on voltage of 2.4 V and high external quantum efficiencies (EQE) of 25.0% and 22.8%, respectively. Moreover, the OLEDs showed low roll-off of efficiency with an EQE of over 21% and 19.6% at 10,000 cd/m2, respectively. The devices displayed good orange color with very little color shift with increasing luminance. The transient electroluminescence of the OLEDs indicated that both energy transfer and direct charge trapping took place in the devices.

Ultrathin nondoped emissive layers for efficient and simple monochrome and white organic light-emitting diodes.

PubMed

Zhao, Yongbiao; Chen, Jiangshan; Ma, Dongge

2013-02-01

In this paper, highly efficient and simple monochrome blue, green, orange, and red organic light emitting diodes (OLEDs) based on ultrathin nondoped emissive layers (EMLs) have been reported. The ultrathin nondoped EML was constructed by introducing a 0.1 nm thin layer of pure phosphorescent dyes between a hole transporting layer and an electron transporting layer. The maximum external quantum efficiencies (EQEs) reached 17.1%, 20.9%, 17.3%, and 19.2% for blue, green, orange, and red monochrome OLEDs, respectively, indicating the universality of the ultrathin nondoped EML for most phosphorescent dyes. On the basis of this, simple white OLED structures are also demonstrated. The demonstrated complementary blue/orange, three primary blue/green/red, and four color blue/green/orange/red white OLEDs show high efficiency and good white emission, indicating the advantage of ultrathin nondoped EMLs on constructing simple and efficient white OLEDs.

Multispectral visualization of surgical safety-margins using fluorescent marker seeds

PubMed Central

Chin, Patrick TK; Beekman, Chantal AC; Buckle, Tessa; Josephson, Lee; van Leeuwen, Fijs WB

2012-01-01

Optical guidance provided by luminescent marker seeds may be suitable for intraoperative determination of appropriate resection margins. In phantom studies we compared the tissue penetration of several organic dyes and inorganic particles (quantum dots; QDs) after incorporation in experimental marker seeds. The tissue penetration of (near infra-) red organic dyes was much better than the penetration of dyes and QDs with an emission in the visible range. By combining 3 dyes in a single marker seed we were able to distinguish four depth ranges. The difference in tissue penetration between the dyes and QDS enabled depth estimation via a ‘traffic light’ approach. PMID:23133810

Predicting solvatochromic shifts and colours of a solvated organic dye: The example of nile red

NASA Astrophysics Data System (ADS)

Zuehlsdorff, T. J.; Haynes, P. D.; Payne, M. C.; Hine, N. D. M.

2017-03-01

The solvatochromic shift, as well as the change in colour of the simple organic dye nile red, is studied in two polar and two non-polar solvents in the context of large-scale time-dependent density-functional theory (TDDFT) calculations treating large parts of the solvent environment from first principles. We show that an explicit solvent representation is vital to resolve absorption peak shifts between nile red in n-hexane and toluene, as well as acetone and ethanol. The origin of the failure of implicit solvent models for these solvents is identified as being due to the strong solute-solvent interactions in form of π-stacking and hydrogen bonding in the case of toluene and ethanol. We furthermore demonstrate that the failures of the computationally inexpensive Perdew-Burke-Ernzerhof (PBE) functional in describing some features of the excited state potential energy surface of the S1 state of nile red can be corrected for in a straightforward fashion, relying only on a small number of calculations making use of more sophisticated range-separated hybrid functionals. The resulting solvatochromic shifts and predicted colours are in excellent agreement with experiment, showing the computational approach outlined in this work to yield very robust predictions of optical properties of dyes in solution.

Efficient Covalent Modification of Multiwalled Carbon Nanotubes with Diazotized Dyes in Water at Room Temperature.

PubMed

Bensghaïer, Asma; Lau Truong, Stéphanie; Seydou, Mahamadou; Lamouri, Aazdine; Leroy, Eric; Mičušik, Matej; Forro, Klaudia; Beji, Mohamed; Pinson, Jean; Omastová, Mária; Chehimi, Mohamed M

2017-07-11

Tetrafluoroborate salts of diazotized Azure A (AA-N 2 + ), Neutral Red (NR-N 2 + ) and Congo Red (CR-N 2 + ) dyes were prepared and reacted with multiwalled carbon nanotubes (MWCNTs) at room temperature, in water without any reducing agent. The as-modified MWCNTs were examined by IRATR, Raman spectroscopy, XPS, TGA, TEM, and cyclic voltammetry. The diazonium band located at ∼2350 cm -1 in the diazotized dye IR spectra vanished after attachment to the nanotubes whereas the Raman D/G peak ratio slightly increased after dye covalent attachment at a high initial diazonium/CNT mass ratio. XPS measurements show the loss of F 1s from the BF 4 - anion together with a clear change in the high-resolution C 1s region from the modified nanotubes. Thermogravimetric analyses proved substantial mass loadings of the organic grafts leveling off at 40.5, 34.3, and 50.7 wt % for AA, NR, and CR, respectively. High-resolution TEM pictures confirmed the presence of 1.5-7-nm-thick continuous amorphous layers on the nanotubes assigned to the aryl layers from the dyes. Cyclic voltammetry studies in acetonitrile (ACN) confirmed the grafting of the dyes; the latter retain their electrochemical behavior in the grafted state. The experimental results correlate remarkably well with quantum chemical calculations that indicate high binding energies between the dyes and the CNTs accounting for true covalent bonding (140-185 kJ/mol with the CNT-aryl distance <1.6 nm), though attachment by π stacking also contributes to obtaining stable hybrids. Finally, the pH-responsive character of the robust hybrids was demonstrated by a higher degree of protonation of Neutral Red-grafted CNTs at pH 2 compared to that of the neutral aqueous medium. This work demonstrates that diazotized dyes can be employed for the surface modification of MWCNTs in a very simple and efficient manner in water and at room temperature. The hybrids could be employed for many purposes such as optically pH-responsive materials, biosensors, and optothermal composite actuators to name a few.

Fundamental Investigations into the Infrared Properties of Carbon Nanotubes

DTIC Science & Technology

2013-01-23

Judy Wu. Development of Nanopatterned Fluorine-Doped Tin Oxide Electrodes for Dye-Sensitized Solar Cells with Improved Light Trapping, ACS Applied...heterojunction solar cell photocurrent enhancement, Nanoscale, (06 2012): 0. doi: 10.1039/c2nr30735a 08/30/2011 1.00 Rongtao Lu, Rayyan Kamal, Judy Z Wu...Jun Li, Judy Wu. The effect of annealing on the photoconductivity of carbon nanofiber/TiO2core-shell nanowires for use in dye-sensitized solar cells

Treatment of simulated wastewater containing Reactive Red 195 by zero-valent iron/activated carbon combined with microwave discharge electrodeless lamp/sodium hypochlorite.

PubMed

Fu, Jie; Xu, Zhen; Li, Qing-Shan; Chen, Song; An, Shu-Qing; Zeng, Qing-Fu; Zhu, Hai-Liang

2010-01-01

A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon (ZVI/AC), microwave discharge electrodeless lamp/sodium hypochlorite (MDEL/NaClO) and the combination of ZVI/AC-MDEL/NaClO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher degradation efficiency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%. The effects of operational parameters, including initial pH value of simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic effect between ZVI/AC and MEDL/NaClO, we found that in the ZVI/AC-MEDL/NaClO process, ZVI/AC could break the azo bond firstly and then MEDL/NaClO degraded the aromatic amine products effectively. Reversing the order would reduce the degradation efficiency.

Removal of anionic dye Congo red from aqueous solution by raw pine and acid-treated pine cone powder as adsorbent: equilibrium, thermodynamic, kinetics, mechanism and process design.

PubMed

Dawood, Sara; Sen, Tushar Kanti

2012-04-15

Pine cone a natural, low-cost agricultural by-product in Australia has been studied for its potential application as an adsorbent in its raw and hydrochloric acid modified form. Surface study of pine cone and treated pine cone was investigated using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The modification process leads to increases in the specific surface area and decreases mean particle sizes of acid-treated pine cone when compared to raw pine cone biomass. Batch adsorption experiments were performed to remove anionic dye Congo red from aqueous solution. It was found that the extent of Congo red adsorption by both raw pine cone biomass and acid-treated biomass increased with initial dye concentration, contact time, temperature but decreased with increasing solution pH and amount of adsorbent of the system. Overall, kinetic studies showed that the dye adsorption process followed pseudo-second-order kinetics based on pseudo-first-order and intra-particle diffusion models. The different kinetic parameters including rate constant, half-adsorption time, and diffusion coefficient were determined at different physico-chemical conditions. Equilibrium data were best represented by Freundlich isotherm model among Langmuir and Freundlich adsorption isotherm models. It was observed that the adsorption was pH dependent and the maximum adsorption of 32.65 mg/g occurred at pH of 3.55 for an initial dye concentration of 20 ppm by raw pine cone, whereas for acid-treated pine cone the maximum adsorption of 40.19 mg/g for the same experimental conditions. Freundlich constant 'n' also indicated favourable adsorption. Thermodynamic parameters such as ∆G(0), ∆H(0), and ∆S(0) were calculated. A single-stage batch absorber design for the Congo red adsorption onto pine cone biomass also presented based on the Freundlich isotherm model equation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sorption Behavior of Dye Compounds onto Natural Sediment of Qinghe River.

PubMed

Liu, Ruixia; Liu, Xingmin; Tang, Hongxiao; Su, Yongbo

2001-07-15

The objective of this study is to assess the adsorption behavior of C.I. Basic Yellow X-5GL, C.I. Basic Red 13, C.I. Direct Blue 86, C.I. Vat Yellow 2, and C.I. Mordant Black 11 on natural sediment and to identify sediment characteristics that play a predominant role in the adsorption of the dyes. The potentiometric titration experiment is used to investigate acid-base properties of the sediment surface with a constant capacitance surface complexation model. The parameters controlling the sorption such as solution pH and ion strength, as well as the influence of organic carbon and Ca(2+) ion on the adsorption, are evaluated. It is shown that the titration data can be successfully described by the surface protonation and deprotonation model with the least-squares FITEQL program 2.0. The sorption isotherm data are fitted to the Freundlich equation in a nonlinear form (1/n=0.3-0.9) for all tested dyes. With increasing pH value, the sorption of C.I. Mordant Black 11 and C.I. Direct Blue 86 on the sediment decreases, while for C.I. Basic Yellow X-5GL and C.I. Basic Red 13, the extent of sorption slightly increases. In addition, ion strength also exhibits a considerably different effect on the sorption behavior of these dye compounds. The addition of Ca(2+) can greatly reduce the sorption of C.I. Basic Red 13 on the sediment surface, while it enhances the sorption of C.I. Direct Blue 6. The removal of organic carbon decreases the sorption of C.I. Mordant Black 11 and C.I. Direct Blue 86. In contrast, the sorption of C.I. Basic Red 13 and C.I. Basic Yellow X-5GL is obviously enhanced after the removal of organic carbon. The differences in adsorption behavior are mainly attributed to the physicochemical properties of these dye compounds. Copyright 2001 Academic Press.

Discoloration and detoxicification of a Congo red dye solution by means of ozone treatment for a possible water reuse.

PubMed

Khadhraoui, M; Trabelsi, H; Ksibi, M; Bouguerra, S; Elleuch, B

2009-01-30

The objective of this study was to investigate the degradation and mineralization of an azo-dye, the Congo red, in aqueous solutions using ozone. Phytotoxicity and the inhibitory effects on the microbial activity of the raw and the ozonated solutions were also carried out with the aim of water reuse and environment protection. Decolorization of the aqueous solutions, disappearance of the parent compound, chemical oxygen demand (COD) and total organic carbon (TOC) removal were the main parameters monitored in this study. To control the mineralization of the Congo red, pH of the ozonated solution and heteroatoms released from the mother molecule such NH(4)(+), NO(3)(-) and SO(4)(2-) were determined. It was concluded that ozone by itself is strong enough to decolorize these aqueous solutions in the early stage of the oxidation process. Nonetheless, efficient mineralization had not been achieved. Significant drops in COD (54%) were registered. The extent of TOC removal was about 32%. Sulfur heteroatom was totally oxidized to SO(4)(2-) ions while the central -NN- azo ring was partially converted to NH(4)(+) and NO(3)(-). Results of the kinetic studies showed that ozonation of the selected molecule was a pseudo-first-order reaction with respect to dye concentration. The obtained results also demonstrate that ozone process reduced the phytotoxicity of the raw solution and enhanced the biodegradability of the treated azo-dyes-wastewater. Hence, this show that ozone remains one of the effective technologies for the discoloration and the detoxification of organic dyes in wastewater.

Spatially variant red blood cell crenation in alternating current non-uniform fields.

PubMed

An, Ran; Wipf, David O; Minerick, Adrienne R

2014-03-01

Alternating-current (AC) electrokinetics involve the movement and behaviors of particles or cells. Many applications, including dielectrophoretic manipulations, are dependent upon charge interactions between the cell or particle and the surrounding medium. Medium concentrations are traditionally treated as spatially uniform in both theoretical models and experiments. Human red blood cells (RBCs) are observed to crenate, or shrink due to changing osmotic pressure, over 10 min experiments in non-uniform AC electric fields. Cell crenation magnitude is examined as functions of frequency from 250 kHz to 1 MHz and potential from 10 Vpp to 17.5 Vpp over a 100 μm perpendicular electrode gap. Experimental results show higher peak to peak potential and lower frequency lead to greater cell volume crenation up to a maximum volume loss of 20%. A series of experiments are conducted to elucidate the physical mechanisms behind the red blood cell crenation. Non-uniform and uniform electrode systems as well as high and low ion concentration experiments are compared and illustrate that AC electroporation, system temperature, rapid temperature changes, medium pH, electrode reactions, and convection do not account for the crenation behaviors observed. AC electroosmotic was found to be negligible at these conditions and AC electrothermal fluid flows were found to reduce RBC crenation behaviors. These cell deformations were attributed to medium hypertonicity induced by ion concentration gradients in the spatially nonuniform AC electric fields.

Bi-fluorescence imaging for estimating accurately the nuclear condition of Rhizoctonia spp.

USDA-ARS?s Scientific Manuscript database

Aims: To simplify the determination of the nuclear condition of the pathogenic Rhizoctonia, which currently needs to be performed either using two fluorescent dyes, thus is more costly and time-consuming, or using only one fluorescent dye, and thus less accurate. Methods and Results: A red primary ...

Extrinsic Fluorescent Dyes as Tools for Protein Characterization

PubMed Central

Hawe, Andrea; Sutter, Marc

2008-01-01

Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are affected by the environment and by interactions of the dyes with proteins. In recent time, the use of extrinsic fluorescent dyes such as ANS, Bis-ANS, Nile Red, Thioflavin T and others has increased, because of their versatility, sensitivity and suitability for high-throughput screening. The intention of this review is to give an overview of available extrinsic dyes, explain their spectral properties, and show illustrative examples of their various applications in protein characterization. PMID:18172579

Photodynamic Inactivation of Acinetobacter baumannii Using Phenothiazinium Dyes: In Vitro and In Vivo Studies

PubMed Central

Ragàs, Xavier; Dai, Tianhong; Tegos, George P.; Agut, Montserrat; Nonell, Santi; Hamblin, Michael R.

2010-01-01

Background and Objective Phenothiazinium dyes have been reported to be effective photosensitizers inactivating a wide range of microorganisms in vitro after illumination with red light. However, their application in vivo has not extensively been explored. This study evaluates the bactericidal activity of phenothiazinium dyes against multidrug-resistant Acinetobacter baumannii both in vitro and in vivo. Study Design/Materials and Methods We report the investigation of toluidine blue O, methylene blue, 1,9-dimethylmethylene blue, and new methylene blue for photodynamic inactivation of multidrug-resistant A. baumannii in vitro. The most effective dye was selected to carry out in vivo studies using third-degree mouse burns infected with a bioluminescent A. baumannii strain, upon irradiation with a 652 nm noncoherent light source. The mice were imaged daily for 2 weeks to observe differences in the bioluminescence–time curve between the photodynamic therapy (PDT)-treated mice in comparison with untreated burns. Results All the dyes were effective in vitro against A. baumannii after 30 J/cm2 irradiation of 635 or 652 nm red light had been delivered, with more effective killing when the dye remained in solution. New methylene blue was the most effective of the four dyes, achieving a 3.2-log reduction of the bacterial luminescence during PDT in vivo after 360 J/cm2 and an 800 μM dye dose. Moreover, a statistically significant reduction of the area under the bioluminescence–time curve of PDT-treated mice was observed showing that the infection did not recur after PDT. Conclusions Phenothiazinium dyes, and especially new methylene blue, are potential photosensitizers for PDT to treat burns infected with multidrug-resistant A. baumannii in vivo. PMID:20583252

Artificial neural network and particle swarm optimization for removal of methyl orange by gold nanoparticles loaded on activated carbon and Tamarisk.

PubMed

Ghaedi, M; Ghaedi, A M; Ansari, A; Mohammadi, F; Vafaei, A

2014-11-11

The influence of variables, namely initial dye concentration, adsorbent dosage (g), stirrer speed (rpm) and contact time (min) on the removal of methyl orange (MO) by gold nanoparticles loaded on activated carbon (Au-NP-AC) and Tamarisk were investigated using multiple linear regression (MLR) and artificial neural network (ANN) and the variables were optimized by partial swarm optimization (PSO). Comparison of the results achieved using proposed models, showed the ANN model was better than the MLR model for prediction of methyl orange removal using Au-NP-AC and Tamarisk. Using the optimal ANN model the coefficient of determination (R2) for the test data set were 0.958 and 0.989; mean squared error (MSE) values were 0.00082 and 0.0006 for Au-NP-AC and Tamarisk adsorbent, respectively. In this study a novel and green approach were reported for the synthesis of gold nanoparticle and activated carbon by Tamarisk. This material was characterized using different techniques such as SEM, TEM, XRD and BET. The usability of Au-NP-AC and activated carbon (AC) Tamarisk for the methyl orange from aqueous solutions was investigated. The effect of variables such as pH, initial dye concentration, adsorbent dosage (g) and contact time (min) on methyl orange removal were studied. Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models indicate that the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed Au-NP-AC and activated carbon (0.015 g and 0.75 g) is applicable for successful removal of methyl orange (>98%) in short time (20 min for Au-NP-AC and 45 min for Tamarisk-AC) with high adsorption capacity 161 mg g(-1) for Au-NP-AC and 3.84 mg g(-1) for Tamarisk-AC. Copyright © 2014 Elsevier B.V. All rights reserved.

Artificial neural network and particle swarm optimization for removal of methyl orange by gold nanoparticles loaded on activated carbon and Tamarisk

NASA Astrophysics Data System (ADS)

Ghaedi, M.; Ghaedi, A. M.; Ansari, A.; Mohammadi, F.; Vafaei, A.

2014-11-01

The influence of variables, namely initial dye concentration, adsorbent dosage (g), stirrer speed (rpm) and contact time (min) on the removal of methyl orange (MO) by gold nanoparticles loaded on activated carbon (Au-NP-AC) and Tamarisk were investigated using multiple linear regression (MLR) and artificial neural network (ANN) and the variables were optimized by partial swarm optimization (PSO). Comparison of the results achieved using proposed models, showed the ANN model was better than the MLR model for prediction of methyl orange removal using Au-NP-AC and Tamarisk. Using the optimal ANN model the coefficient of determination (R2) for the test data set were 0.958 and 0.989; mean squared error (MSE) values were 0.00082 and 0.0006 for Au-NP-AC and Tamarisk adsorbent, respectively. In this study a novel and green approach were reported for the synthesis of gold nanoparticle and activated carbon by Tamarisk. This material was characterized using different techniques such as SEM, TEM, XRD and BET. The usability of Au-NP-AC and activated carbon (AC) Tamarisk for the methyl orange from aqueous solutions was investigated. The effect of variables such as pH, initial dye concentration, adsorbent dosage (g) and contact time (min) on methyl orange removal were studied. Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models indicate that the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed Au-NP-AC and activated carbon (0.015 g and 0.75 g) is applicable for successful removal of methyl orange (>98%) in short time (20 min for Au-NP-AC and 45 min for Tamarisk-AC) with high adsorption capacity 161 mg g-1 for Au-NP-AC and 3.84 mg g-1 for Tamarisk-AC.

Instability of monoclonal myeloma protein may be identified as susceptibility to penetration and binding by newly synthesized Congo red derivatives.

PubMed

Spólnik, Paweł; Konieczny, Leszek; Piekarska, Barbara; Rybarska, Janina; Stopa, Barbara; Zemanek, Grzegorz; Król, Marcin; Roterman, Irena

2004-06-01

Monoclonal myeloma proteins often have an abnormal, unstable structure, and tend to aggregate with fatal clinical consequences. A method for early clinical identification of this aggregation tendency is impatiently awaited. This work proposes the use of supramolecular dyes as specific ligands to reveal protein instability. Disclosure of excessive polypeptide chain flexibility in unstable monoclonal proteins, leading to increased susceptibility to penetration by foreign compounds, appeared possible when new supramolecular Congo red-derived dyes with different protein-binding capabilities were used for complexation. Two basic protein instability levels, local and global, were differentiated by comparing the extent of protein loading with dye and the subsequent electrophoretic migration rate of the complexes. A simple electrophoretic test is proposed for assessment of the instability of monoclonal proteins in clinical conditions.

Visible light photoactivity of Polypropylene coated Nano-TiO2 for dyes degradation in water

PubMed Central

Giovannetti, R.; Amato, C. A. D’; Zannotti, M.; Rommozzi, E.; Gunnella, R.; Minicucci, M.; Di Cicco, A.

2015-01-01

The use of Polypropylene as support material for nano-TiO2 photocatalyst in the photodegradation of Alizarin Red S in water solutions under the action of visible light was investigated. The optimization of TiO2 pastes preparation using two commercial TiO2, Aeroxide P-25 and Anatase, was performed and a green low-cost dip-coating procedure was developed. Scanning electron microscopy, Atomic Force Microscopy and X-Ray Diffraction analysis were used in order to obtain morphological and structural information of as-prepared TiO2 on support material. Equilibrium and kinetics aspects in the adsorption and successive photodegradation of Alizarin Red S, as reference dye, are described using polypropylene-TiO2 films in the Visible/TiO2/water reactor showing efficient dyes degradation. PMID:26627118

Photodynamic therapy: a synergy between light and colors

NASA Astrophysics Data System (ADS)

Merigo, Elisabetta; Sozzi, Michele; Ciociola, Tecla; Conti, Stefania; Fornaini, Carlo; Vescovi, Paolo; Selleri, Stefano; Cucinotta, Annamaria

2015-02-01

In this work the application of different laser wavelengths, in combination with different photosensitizing dyes, to bacterial cultures, in liquid or solid mean, has been investigated. Two types of Streptococcus mutans cultures have been used for the experiments, inside agar and saline solution. Three different laser wavelengths have been applied to the bacterial cultures together with a photosensitizing dye: red diode (650 nm) on cultures stained with Toluidine Blue, blueviolet diode (450 nm) on cultures stained with Curcumin and KTP laser (532 nm) on cultures stained with Erythrosine. The choice of the dye has been made considering the color affinity with the used wavelength. Tests without dyes have also been performed. Experimental results show that the maximum inhibition of bacterial growth with the blue laser has been obtained in a saline solution with a growth of 40.77%. While the combination with Curcumin lead to an inhibition growth of about 99.1%, for a laser fluence of 30J/cm2. No inhibition has been observed using the red laser in saline solution without dye, while the combination with Toluidine Blue resulted in a 100% inhibition growth for 20 and 30 J/cm2 fluences. An inhibition growth of just 16.26% has been obtained with the use of KTP laser in saline solution without dye. The use of Erythrosine had the effect of a complete inhibition growth. From the obtained results it is possible to observe that the combination of laser wavelength with a particular photosensitizing dye can dramatically increase the bacterial growth.

The Bioluminescence Resonance Energy Transfer from Firefly Luciferase to a Synthetic Dye and its Application for the Rapid Homogeneous Immunoassay of Progesterone.

PubMed

Smirnova, Daria V; Samsonova, Jeanne V; Ugarova, Natalia N

2016-01-01

The sensitive BRET system for the homogeneous immunoassay of a low-molecular weight antigen was developed using progesterone as an example. Two thermostable mutants of the Luciola mingrelica firefly luciferase (Luc)-the "red" mutant with λmax.em = 590 nm (RedLuc) and the "green" mutant with λmax.em = 550 nm (GreenLuc)-were tested as the donors. The water-soluble Alexa Fluor 610× (AF) dye was selected as the acceptor because its two absorption maxima, located at 550 and 610 nm, are close to the bioluminescence maxima of the GreenLuc and RedLuc, respectively. The methods for the synthesis of the luciferase-progesterone (Luc-Pg) conjugate and the conjugate of the dye and the polyclonal antiprogesterone antibody (AF-Ab) were developed. Both conjugates retained their functional properties, had high antigen-antibody binding activity, and demonstrated a high BRET signal. The homogeneous immunoassay system based on the BRET from the firefly luciferase to the synthetic dye was established to assay progesterone as a model antigen. Optimization of the assay conditions, the composition of the reaction mixture, and the concentrations of the donor and the acceptor made it possible to reach the minimum detectable progesterone concentration of 0.5 ng mL(-1) . © 2015 The American Society of Photobiology.

Sequential decolorization of azo dye and mineralization of decolorization liquid coupled with bioelectricity generation using a pH self-neutralized photobioelectrochemical system operated with polarity reversion.

PubMed

Sun, Jian; Hu, Yongyou; Li, Wanjun; Zhang, Yaping; Chen, Jie; Deng, Feng

2015-05-30

A novel photobioelectrochemical system (PBES) was developed by acclimating algal-bacterial biofilm in both anode and cathode using Chlorella vulgaris and indigenous wastewater bacteria as inoculums. The PBES was operated in polarity reversion mode depend on dark/light alternate reaction to achieve simultaneous pH self-neutralization, azo dye degradation (Congo red) and bioelectricity generation. The anodic accumulated acidity and cathodic accumulated alkalinity were self-neutralized after polarity reversion and hence eliminate the membrane pH gradient. The Congo red was first decolored in the dark anode and the resultant decolorization liquid was subsequently mineralized after the dark anode changing to the photo-biocathode. The presence of C. vulgaris significantly enhanced the two-stage degradation of Congo red, with 93% increases in decolorization rates and 8% increases in mineralization compared to the algae-free BES. The PBES continuously generated stable voltage output over four months under repeatedly reversion of polarity. The maximum power density produced before and after polarity reversion was 78 and 61 mW/m(2), respectively. The synergy between C. vulgaris and mixed bacteria was responsible for the successful operation of the PBES which can be potentially applied to treat wastewater containing azo dye with benefits of enhanced azo dye degradation, high net power output and buffer minimization. Copyright © 2015 Elsevier B.V. All rights reserved.

Grafting of aniline derivatives onto chitosan and their applications for removal of reactive dyes from industrial effluents.

PubMed

Abbasian, Mojtaba; Jaymand, Mehdi; Niroomand, Pouneh; Farnoudian-Habibi, Amir; Karaj-Abad, Saber Ghasemi

2017-02-01

A series of chitosan-grafted polyaniline derivatives {chitosan-g-polyaniline (CS-g-PANI), chitosan-g-poly(N-methylaniline) (CS-g-PNMANI), and chitosan-g-poly(N-ethylaniline) (CS-g-PNEANI)} were synthesized by in situ chemical oxidation polymerization method. The synthesized copolymers were analyzed by means of Fourier transform infrared (FTIR), and ultraviolet-visible (UV-vis) spectroscopies, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FE-SEM). These copolymers were applied as adsorbent for removal of acid red 4 (AR4) and direct red 23 (DR23) from aqueous solutions. The adsorption processes were optimized in terms of pH, adsorbent amount, and dyes concentrations. The maximum adsorption capacities (Q m ) for the synthesized copolymers were calculated, and among them the CS-g-PNEANI sample showed highest Q m for both AR4 (98mgg -1 ) and DR23 (112mgg -1 ) dyes. The adsorption kinetics of AR4 and DR23 dyes follow the pseudo-second order kinetic model. The regeneration and reusability tests revealed that the synthesized adsorbents had the relatively good reusability after five repetitions of the adsorption-desorption cycles. As the results, it is expected that the CS-g-PANIs find application for removal of reactive dyes (especially anionic dyes) from industrial effluents mainly due to their low production costs and high adsorption effectiveness. Copyright © 2016 Elsevier B.V. All rights reserved.

Hierarchically porous silicon–carbon–nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes

PubMed Central

Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

2015-01-01

The hierarchically macro/micro-porous silicon–carbon–nitrogen (Si–C–N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp2-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7 mg·g−1 and 1084.5 mg·g−1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si–C–N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants. PMID:25604334

Isolation, cloning and characterization of an azoreductase from the halophilic bacterium Halomonas elongata.

PubMed

Eslami, Maryam; Amoozegar, Mohammad Ali; Asad, Sedigheh

2016-04-01

Azo dyes are a major class of colorants used in various industries including textile, paper and food. These dyes are regarded as pollutant since they are not readily reduced under aerobic conditions. Halomonas elongata, a halophilic bacterium, has the ability to decolorize different mono and di-azo dyes in anoxic conditions. In this study the putative azoreductase gene of H. elongata, formerly annotated as acp, was isolated, heterologously expressed in Escherichia coli, purified and characterized. The gene product, AzoH, was found to have a molecular mass of 22 kDa. The enzyme requires NADH, as an electron donor for its activity. The apparent Km was 63 μM for NADH and 12 μM for methyl red as a mono-azo dye substrate. The specific activity for methyl red was 0.27 μmol min(-1)mg(-1). The optimum enzyme activity was achieved in 50mM sodium phosphate buffer at pH 6. Although increased salinity resulted in reduced activity, AzoH could decolorize azo dye at NaCl concentrations up to 15% (w/v). The enzyme was also shown to be able to decolorize remazol black B as a representative of di-azo dyes. This is the first report describing the sequence and activity of an azo-reducing enzyme from a halophilic bacterium. Copyright © 2015 Elsevier B.V. All rights reserved.

Biosorption of Azo dyes by spent Rhizopus arrhizus biomass

NASA Astrophysics Data System (ADS)

Salvi, Neeta A.; Chattopadhyay, S.

2017-10-01

In the present study, spent Rhizopus arrhizus biomass was used for the removal of six azo dyes from aqueous solutions. The dye removal capacity of the biomass was evaluated by conducting batch tests as a function of contact time, biomass dosage, pH and initial dye concentrations. The pseudo-second-order kinetic model fitted well with the experimental data with correlation coefficients greater than 0.999, suggesting that chemisorptions might be the rate limiting step. The equilibrium sorption data showed good fit to the Langmuir isotherm model. Among the six dyes tested, the maximum monolayer adsorption capacity for fast red A and metanil yellow was found to be 108.8 and 128.5 mg/g, respectively. These encouraging results suggest that dead Rhizopus arrhizus biomass could be a potential biomaterial for the removal of azo dyes from aqueous dye solution.

Masked red-emitting carbopyronine dyes with photosensitive 2-diazo-1-indanone caging group.

PubMed

Kolmakov, Kirill; Wurm, Christian; Sednev, Maksim V; Bossi, Mariano L; Belov, Vladimir N; Hell, Stefan W

2012-03-01

Caged near-IR emitting fluorescent dyes are in high demand in optical microscopy but up to now were unavailable. We discovered that the combination of a carbopyronine dye core and a photosensitive 2-diazo-1-indanone residue leads to masked near-IR emitting fluorescent dyes. Illumination of these caged dyes with either UV or visible light (λ < 420 nm) efficiently generates fluorescent compounds with absorption and emission at 635 nm and 660 nm, respectively. A high-yielding synthetic route with attractive possibilities for further dye design is described in detail. Good photostability, high contrast, and a large fluorescence quantum yield after uncaging are the most important features of the new compounds for non-invasive imaging in high-resolution optical microscopy. For use in immunolabelling the caged dyes were decorated with a (hydrophilic) linker and an (activated) carboxyl group.

Electroluminescent Properties in Organic Light-Emitting Diode Doped with Two Guest Dyes

NASA Astrophysics Data System (ADS)

Mori, Tatsuo; Kim, Hyeong-Gweon; Mizutani, Teruyoshi; Lee, Duck-Chool

2001-09-01

An organic light-emitting diode (OLED) with a squarylium dye-doped aluminium quinoline (Alq3) emission layer prepared by vapor deposition method has a pure red emission. However, since its luminance and electroluminescence (EL) efficiency is poor, the authors attended to improve the EL efficiency by doping a photosensitizer dye (a styryl dye, DCM) in an emission layer. The EL efficiency and luminance of DCM- and Sq-doped OLEDs are 2-3 times higher than those of only Sq-doped OLEDs. It was found that the excited energy is transferred from Alq3 to Sq through DCM.

Ag nanoparticle-filled TiO2 nanotube arrays prepared by anodization and electrophoretic deposition for dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Wei, Xing; Sugri Nbelayim, Pascal; Kawamura, Go; Muto, Hiroyuki; Matsuda, Atsunori

2017-03-01

A layer of TiO2 nanotube (TNT) arrays with a thickness of 13 μm is synthesized by a two-step anodic oxidation from Ti metal foil. Surface charged Ag nanoparticles (NPs) are prepared by chemical reduction. After a pretreatment of the TNT arrays by acetone vapor, Ag NP filled TNT arrays can be achieved by electrophoretic deposition (EPD). Effects of the applied voltage during EPD such as DC-AC difference, frequency and waveform are investigated by quantitative analysis using atomic absorption spectroscopy. The results show that the best EPD condition is using DC 2 V + AC 4 V and a square wave of 1 Hz as the applied voltage. Back illuminated dye-sensitized solar cells are fabricated from TNT arrays with and without Ag NPs. The efficiency increased from 3.70% to 5.01% by the deposition of Ag NPs.

Degradation products of the artificial azo dye, Allura red, inhibit esterase activity of carbonic anhydrase II: A basic in vitro study on the food safety of the colorant in terms of enzyme inhibition.

PubMed

Esmaeili, Sajjad; Ashrafi-Kooshk, Mohammad Reza; Khaledian, Koestan; Adibi, Hadi; Rouhani, Shohre; Khodarahmi, Reza

2016-12-15

Allura red is a widely used food colorant, but there is debate on its potential security risk. In the present study, we found that degradation products of the dye were more potent agents with higher carbonic anhydrase inhibitory action than the parent dye. The mechanism by which the compounds inhibit the enzyme activity has been determined as competitive mode. In addition, the enzyme binding properties of the compounds were investigated employing different spectroscopic techniques and molecular docking. The analyses of fluorescence quenching data revealed the existence of the same binding site for the compounds on the enzyme molecule. The thermodynamic parameters of ligand binding were not similar, which indicates that different interactions are responsible in binding of the parent dye and degradation products to the enzyme. It appears that enzyme inhibition should be considered, more seriously, as a new opened dimension in food safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

"siRNA traffic lights": arabino-configured 2'-anchors for fluorescent dyes are key for dual color readout in cell imaging.

PubMed

Steinmeyer, Jeannine; Walter, Heidi-Kristin; Bichelberger, Mathilde A; Schneider, Violetta; Kubař, Tomáš; Rönicke, Franziska; Olshausen, Bettina; Nienhaus, Karin; Nienhaus, Gerd Ulrich; Schepers, Ute; Elstner, Marcus; Wagenknecht, Hans-Achim

2018-05-23

Two fluorescent dyes covalently attached in diagonal interstrand orientation to siRNA undergo energy transfer and thereby enable a dual color fluorescence readout (red/green) for hybridization. Three different structural variations were carried out and compared by their optical properties, including (i) the base surrogate approach with an acyclic linker as a substitute of the 2-deoxyriboside between the phosphodiester bridges, (ii) the 2'-modification of conventional ribofuranosides and (iii) the arabino-configured 2'-modification. The double stranded siRNA with the latter type of modification delivered the best energy transfer efficiency, which was explained by molecular dynamics simulations that showed that the two dyes are more flexible at the arabino-configured sugars compared to the completely stacked situation at the ribo-configured ones. Single molecule fluorescence lifetime measurements indicate their application in fluorescence cell imaging, which reveals a red/green fluorescence contrast in particular for the arabino-configured 2'-modification by the two dyes, which is key for tracking of siRNA transport into HeLa cells.

Efficient degradation of Azo dyes by a newly isolated fungus Trichoderma tomentosum under non-sterile conditions.

PubMed

He, Xiao-Ling; Song, Chao; Li, Yuan-Yuan; Wang, Ning; Xu, Lei; Han, Xin; Wei, Dong-Sheng

2018-04-15

A fast-growing fungus with remarkable ability to degrade several azo dyes under non-sterile conditions was isolated and identified. This fungus was identified as Trichoderma tomentosum. Textile effluent of ten-fold dilution could be decolorized by 94.9% within 72h before optimization. Acid Red 3R model wastewater with a concentration of 85.5mgL -1 could be decolorized by 99.2% within the same time after optimization. High-level of manganese peroxidase and low-level of lignin peroxidase activities were detected during the process of decolorization from the culture supernatant, indicating the possible involvement of two enzymes in azo dye decolorization. No aromatic amine products were detected from the degradation products of Acid Red 3R by gas chromatography-mass spectrometry (GC/MS) analysis, indicating the possible involvement of a special symmetrical oxidative degradation pathway. Phytotoxicity assay confirmed the lower toxicity toward the test plant seeds of the degradation products when compared to the original dye. Copyright © 2017 Elsevier Inc. All rights reserved.

Biosorption of Acid Black 172 and Congo Red from aqueous solution by nonviable Penicillium YW 01: kinetic study, equilibrium isotherm and artificial neural network modeling.

PubMed

Yang, Yuyi; Wang, Guan; Wang, Bing; Li, Zeli; Jia, Xiaoming; Zhou, Qifa; Zhao, Yuhua

2011-01-01

The main objective of this work was to investigate the biosorption performance of nonviable Penicillium YW 01 biomass for removal of Acid Black 172 metal-complex dye (AB) and Congo Red (CR) in solutions. Maximum biosorption capacities of 225.38 and 411.53 mg g(-1) under initial dye concentration of 800 mg L(-1), pH 3.0 and 40 °C conditions were observed for AB and CR, respectively. Biosorption data were successfully described with Langmuir isotherm and the pseudo-second-order kinetic model. The Weber-Morris model analysis indicated that intraparticle diffusion was the limiting step for biosorption of AB and CR onto biosorbent. Analysis based on the artificial neural network and genetic algorithms hybrid model indicated that initial dye concentration and temperature appeared to be the most influential parameters for biosorption process of AB and CR onto biosorbent, respectively. Characterization of the biosorbent and possible dye-biosorbent interaction were confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. Copyright © 2010 Elsevier Ltd. All rights reserved.

Dye-Sensitized Solar Cells (DSSCs) reengineering using TiO2 with natural dye (anthocyanin)

NASA Astrophysics Data System (ADS)

Subodro, Rohmat; Kristiawan, Budi; Ramelan, Ari Handono; Wahyuningsih, Sayekti; Munawaroh, Hanik; Hanif, Qonita Awliya; Saputri, Liya Nikmatul Maula Zulfa

2017-01-01

This research on Dye-Sensitized Solar Cells (DSSCs) reengineering was carried out using TiO2 with natural dye (anthocyanin). The fabrication of active carbon layer/TiO2 DSSC solar cell was based on natural dye containing anthocyanins such as mangosteen peel, red rose flower, black glutinous rice, and purple eggplant peel. DSSC was prepared with TiO2 thin layer doped with active carbon; Natural dye was analyzed using UV-Vis and TiO2 was analyzed using X-ray diffractometer (XRD), meanwhile scanning electron microscope (SEM) was used to obtain the size of the crystal. Keithley instrument test was carried out to find out I-V characteristics indicating that the highest efficiency occurred in DSSCs solar cell with 24-hour soaking with mangosteen peel 0.00047%.

Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

NASA Astrophysics Data System (ADS)

Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

2013-11-01

This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

Thermodynamic and Spectroscopic Investigation of Interactions between Reactive Red 223 and Reactive Orange 122 Anionic Dyes and Cetyltrimethyl Ammonium Bromide (CTAB) Cationic Surfactant in Aqueous Solution

PubMed Central

Irfan, Muhammad; Usman, Muhammad; Mansha, Asim; Rasool, Nasir; Ibrahim, Muhammad; Rana, Usman Ali; Siddiq, Mohammad; Zia-Ul-Haq, Muhammad; Jaafar, Hawa Z. E.; Khan, Salah Ud-Din

2014-01-01

The present study describes the conductometric and spectroscopic study of the interaction of reactive anionic dyes, namely, reactive red 223 and reactive orange 122 with the cationic surfactant cetyltrimethyl ammonium bromide (CTAB). In a systematic investigation, the electrical conductivity data was used to calculate various thermodynamic parameters such as free energy (ΔG), enthalpy (ΔH), and the entropy (ΔS) of solubilization. The trend of change in these thermodynamic quantities indicates toward the entropy driven solubilization process. Moreover, the results from spectroscopic data reveal high degree of solubilization, with strong interactions observed in the cases of both dyes and the CTAB. The spontaneous nature of solubilization and binding was evident from the observed negative values of free energies (ΔG p and ΔG b). PMID:25243216

Synthesis of a Far‐Red Photoactivatable Silicon‐Containing Rhodamine for Super‐Resolution Microscopy

PubMed Central

Grimm, Jonathan B.; Klein, Teresa; Kopek, Benjamin G.; Shtengel, Gleb; Hess, Harald F.; Sauer, Markus

2015-01-01

Abstract The rhodamine system is a flexible framework for building small‐molecule fluorescent probes. Changing N‐substitution patterns and replacing the xanthene oxygen with a dimethylsilicon moiety can shift the absorption and fluorescence emission maxima of rhodamine dyes to longer wavelengths. Acylation of the rhodamine nitrogen atoms forces the molecule to adopt a nonfluorescent lactone form, providing a convenient method to make fluorogenic compounds. Herein, we take advantage of all of these structural manipulations and describe a novel photoactivatable fluorophore based on a Si‐containing analogue of Q‐rhodamine. This probe is the first example of a “caged” Si‐rhodamine, exhibits higher photon counts compared to established localization microscopy dyes, and is sufficiently red‐shifted to allow multicolor imaging. The dye is a useful label for super‐resolution imaging and constitutes a new scaffold for far‐red fluorogenic molecules. PMID:26661345

Intravital multiphoton photoconversion with a cell membrane dye.

PubMed

Turcotte, Raphaël; Wu, Juwell W; Lin, Charles P

2017-02-01

Photoconversion, an irreversible shift in a fluorophore emission spectrum after light exposure, is a powerful tool for marking cellular and subcellular compartments and tracking their dynamics in vivo. This paper reports on the photoconversion properties of Di-8-ANEPPS, a commercially available membrane dye. When illuminated with near-infrared femtosecond laser pulses, Di-8-ANEPPS undergoes multiphoton photoconversion as indicated by the supralinear dependence of the conversion rate ρ pc on the incident power (ρpc∝Iexc2.27), and by the ability to photoconvert a thin optical section in a three-dimensional matrix. The characteristic emission spectrum changed from red to blue, and ratiometric analysis on single cells in vitro revealed a 65-fold increase in the blue to red wavelength ratio after photoconversion. The spectral shift is preserved in vivo for hours, making Di-8-ANEPPS a useful dye for intravital cell marking and tracking applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adsorption properties of congo red from aqueous solution onto N,O-carboxymethyl-chitosan.

PubMed

Wang, Li; Wang, Aiqin

2008-03-01

N,O-carboxymethyl-chitosans (N,O-CMC) with different degree of substitution (DS) were synthesized under heterogeneous conditions by controlling the reaction temperature. The factors influencing adsorption capacity of N,O-CMC such as the DS of N,O-CMC, initial pH value of the dye solution and adsorption temperature for anionic dye congo red (CR) were investigated. Compared with chitosan (78.90 mg/g), N,O-CMC with the DS of 0.35 exhibited much higher adsorption capacity (330.62 mg/g) for CR at the same adsorption conditions. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by pseudo-second-order equation and the Langmuir equation, respectively. The adsorption mechanism of N,O-CMC was also discussed by means of IR and XPS spectra. The results in this study indicated that N,O-CMC was an attractive candidate for removing CR from the dye wastewater.

Methyl Red Decolorization Efficiency of a Korea Strain of Aspergillus sp. Immobilized into Different Polymeric Matrices.

PubMed

Kim, Beom-Su; Blaghen, Mohamed; Lee, Kang-Min

2017-07-01

  Intensive research studies have revealed that fungal decolorization of dye wastewater is a promising replacement for the current process of dye wastewater decolorization. The authors isolated an Aspergillus sp. from the effluent of a textile industry area in Korea and assessed the effects of a variety of operational parameters on the decolorization of methyl red (MR) by this strain of Aspergillus sp. This Aspergillus sp. was then immobilized by entrapment in several polymeric matrices and the effects of operational conditions on MR decolorization were investigated again. The optimal decolorization activity of this Aspergillus sp. was observed in 1% glucose at a temperature of 37 °C and pH of 6.0. Furthermore, stable decolorization efficiency was observed when fungal biomass was immobilized into alginate gel during repeated batch experiment. These results suggest that the Aspergillus sp. isolated in Korea could be used to treat industrial wastewaters containing MR dye.

Multicolor fluorescence "click"-chemistry as a means to select membrane targets for pre-targeting approaches by function of their receptor kinetics.

PubMed

van der Wal, Steffen; de Korne, Clarize M; Sand, Laurens L G; van Willigen, Danny M; Hogendoorn, Pancras C W; Szuhai, Karoly; van Leeuwen, Fijs W B; Buckle, Tessa

2018-06-04

Availability of a receptor for theranostic pre-targeting approaches was assessed using a novel "click" chemistry-based de-activatable fluorescence-quenching concept. Efficacy was evaluated in a cell-based model system that exhibits both membranous (available) and internalized (unavailable) receptor-fractions of the clinically relevant receptor chemokine receptor 4 (CXCR4). Proof of concept was based on a de-activatable tracer consisting out of a CXCR4 specific peptide functionalized with a Cy5 dye comprising a chemo-selective azide handle (N3-Cy5-AcTZ14011). Reaction with a Cy7 quencher dye (Cy7-DBCO) resulted in optically silent Cy7-["click"]-Cy5-AcTZ14011. In situ a >90% FRET-based reduction of signal intensity of N3-Cy5-AcTZ14011 (KD 222.4 ± 25.2 nM) was seen within minutes after quencher addition. In cells, discrimination between the membranous and internalized receptor-fraction could be made through quantitative assessment of quenching/internalization kinetics. As such, using this approach screening of membrane receptors and their applicability in receptor-(pre-)targeted theranostics can become straightforward. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Novel Preparation Method of Two Polymer Dyes with Low Cytotoxicity

PubMed Central

Lv, Dongjun; Zhang, Mingjie; Cui, Jin; Li, Weixue; Zhu, Guohua

2017-01-01

A new preparation method of polymer dyes was developed to improve both the grafting degree of the azo dyes onto O-carboxymethyl chitosan (OMCS) and the water solubility of prepared polymer dyes. Firstly, the coupling compound of two azo edible colorants, sunset yellow (SY) and allura red (AR), was grafted onto OMCS, and then coupled with their diazonium salt. The chemical structure of prepared polymer dyes was determined by Fourier transform-infrared spectroscopy and 1H-NMR, and the results showed that the two azo dyes were successfully grafted onto OMCS. The grafting degree onto OMCS and the water solubility of polymer dyes were tested, and the results showed that they were both improved as expected. The UV-vis spectra analysis results showed that the prepared polymer dyes showed similar color performance with the original azo dyes. Eventually, the cytotoxicity of prepared polymer dyes was tested and compared with the original azo dyes by a cytotoxicity test on human liver cell lines LO2, and the results showed that their grafting onto OMCS significantly reduced the cytotoxicity. PMID:28772583

In-vivo studies of reflectance pulse oximeter sensor

NASA Astrophysics Data System (ADS)

Ling, Jian; Takatani, Setsuo; Noon, George P.; Nose, Yukihiko

1993-08-01

Reflectance oximetry can offer an advantage of being applicable to any portion of the body. However, the major problem of reflectance oximetry is low pulsatile signal level which prevents prolonged clinical application during extreme situations, such as hypothermia and vasoconstriction. In order to improve the pulsatile signal level of reflectance pulse oximeter and thus its accuracy, three different sensors, with the separation distances (SPD) between light emitting diode (LED) and photodiode being 3, 5, and 7 mm respectively, were studied on nine healthy volunteers. With the increase of the SPD, it was found that both the red (660 nm) and near-infrared (830 nm) pulsatile to average signal ratio (AC/DC) increased, and the standard deviations of (AC/DC)red/(AC/DC)infrared ratio decreased, in spite of the decrease of the absolute signal level. Further clinical studies of 3 mm and 7 mm SPD sensors on seven patients also showed that the (AC/DC)red/(AC/DC)infrared ratio measured by the 7 mm sensor were less disturbed than the 3 mm sensor during the surgery. A theoretical study based on the three-dimensional photon diffusion theory supports the experimental and clinical results. As a conclusion, the 7 mm sensor has the highest signal-to- noise ratio among three different sensors. A new 7 mm SPD reflectance sensor, with the increased number of LEDs around the photodiode, was designed to increase the AC/DC ratio, as well as to increase the absolute signal level.

Power ultrasound-assisted cleaner leather dyeing technique: influence of process parameters.

PubMed

Sivakumar, Venkatasubramanian; Rao, Paruchuri Gangadhar

2004-03-01

The application of power ultrasound to leather processing has a significant role in the concept of "clean technology" for leather production. The effect of power ultrasound in leather dyeing has been compared with dyeing in the absence of ultrasound and conventional drumming. The power ultrasound source used in these experiments was ultrasonic cleaner (150 W and 33 kHz). The effect of various process parameters such as amount of dye offer, temperature, and type of dye has been experimentally found out. The effect of presonication of dye solution as well as leather has been studied. Experiments at ultrasonic bath temperature were carried out to find out the combined thermal as well as stirring effects of ultrasound. Dyeing in the presence of ultrasound affords about 37.5 (1.8 times) difference as increase in % dye exhaustion or about 50% decrease in the time required for dyeing compared to dyeing in the absence of ultrasound for 4% acid red dye. About 29 (1.55 times) increase in % dye exhaustion or 30% reduction in time required for dyeing was observed using ultrasound at stationary condition compared with conventional dynamic drumming conditions. The effect of ultrasound at constant temperature conditions with a control experiment has also been studied. The dye exhaustion increases as the temperature increases (30-60 degrees C) and better results are observed at higher temperature due to the use of ultrasound. Presonication of dye solution or crust leather prior to the dyeing process has no significant improvement in dye exhaustion, suggesting ultrasound effect is realized when it is applied during the dyeing process. The results indicate that 1697 and 1416 ppm of dye can be reduced in the spent liquor due to the use of ultrasound for acid red (for 100 min) and acid black (for 3 h) dyes, respectively, thereby reducing the pollution load in the effluent stream. The color yield of the leather as inferred from the reflectance measurement indicates that dye offer can be halved when ultrasound is employed to promote dyeing. Scanning electron microscopy analysis of the cross section of the dyed leather indicates that fiber structure is not affected due to the use of ultrasound under the given process conditions. The present study clearly demonstrates that ultrasound can be used as a tool to improve the rate of exhaustion of dye, reduce pollution load in the spent effluent liquor, and improve the quality of leather produced. The study also offered provision to employ optimum levels of chemicals and increases percentage exhaustion for a given time, thereby limiting the pollution load in the tannery effluent, which is of great social concern.

Influence of auxochrome group in disperse dyes bearing azo groups as chromophore center in the biotransformation and molecular docking prediction by reductase enzyme: Implications and assessment for environmental toxicity of xenobiotics.

PubMed

Franco, Jefferson Honorio; da Silva, Bianca F; Dias, Elisangela Franciscon G; de Castro, Alexandre A; Ramalho, Teodorico C; Zanoni, Maria Valnice Boldrin

2018-05-21

Synthetic azo dyes have increasingly become a matter of great concern as a result of the genotoxic and mutagenic potential of the products derived from azo dye biotransformation. This work evaluates the manner in which reducing enzymes produced by Escherichia coli (E. coli) act on three disperse dyes bearing azo groups, namely Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). UV-Vis spectrophotometry, high-performance liquid chromatography with diode array detector (HPLC-DAD), and liquid chromatography mass spectrometry (LC-MS/MS) were applied towards the identification of the main products. Seven days of incubation of the azo dyes with the tested enzymes yielded a completely bleached solution. 3-4-Aminophenyl-ethyl-amino-propanitrile was detected following the biotransformation of both DR 73 and DR 78. 4-Nitroaniline and 2-chloro-4-nitroaniline were detected upon the biotransformation of DR 73 and DR 78, respectively. The main products derived from the biotransformation of DR 167 were dimethyl 3,3'-3-acetamido-4-aminophenyl-azanedyl-dipropanoate and 2-chloro-4-nitroaniline. The results imply that DR 73 lost the CN - substituent during the biotransformation. Furthermore, theoretical calculations were also carried out aiming at evaluating the interaction and reactivity of these compounds with DNA. Taken together, the results indicate that DR 73, DR 78, and DR 167 pose health risks and serious threats to both human beings and the environment at large as their biotransformation produces harmful compounds such as amines, which have been widely condemned by the International Agency for Research on Cancer. Copyright © 2018. Published by Elsevier Inc.

Simplification and improvement of protein detection in two-dimensional electrophoresis gels with SERVA HPE™ lightning red.

PubMed

Griebel, Anja; Obermaier, Christian; Westermeier, Reiner; Moche, Martin; Büttner, Knut

2013-07-01

A new fluorescent amino-reactive dye has been tested for both labelling proteins prior to electrophoretic separations and between the two steps of two-dimensional electrophoresis. A series of experiments showed, that the labelling of lysines with this dye is compatible with all standard additives used for sample preparation, including reducing substances and carrier ampholytes. Using this dye for pre-labelling considerably simplifies the electrophoresis and detection workflow and provides highly sensitive and quantitative visualisation of proteins.

Preparation of anti-Sudan red monoclonal antibody and development of an indirect competitive enzyme-linked immunosorbent assay for detection of Sudan red in chilli jam and chilli oil.

PubMed

Xu, Jing; Zhang, Yuanyang; Yi, Jian; Meng, Meng; Wan, Yuping; Feng, Caiwei; Wang, Shanliang; Lu, Xiao; Xi, Rimo

2010-10-01

Sudan dyes are banned to be used in food additives because of the carcinogenicity of their metabolites. A rapid and sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed to detect the residues of Sudan dyes. Novel immunogen and coating antigen were synthesized via glutaraldehyde linking. The hapten-bovine serum albumin (BSA) was applied as immunogen and the hapten-ovalbumin (OVA) was served as coating antigen. The monoclonal antibody obtained showed high sensitivity to Sudan I with an IC(50) value of 1.7 μg L(-1) in buffer and was suitable to detect the residues of Sudan red in food products. The specificity of the assay was studied by measuring cross-reactivity of the antibody with the structurally related compounds of Sudan II (<1%), Sudan IV (<1%) and para red (120%). Chilli jam and chilli oil samples spiked with Sudan dyes were analyzed by the method. The detection limit (LOD) of the ELISA method applied in chilli jam and chilli oil was 9.0 μg L(-1) and 19.6 μg L(-1), respectively. The recovery rates of Sudan-I in chilli oil and chilli jam were in the range of 80%-110% with coefficients of variation <25%. The intra-assay variation and inter-assay variation in buffer were both <9%.

The Orange Side of Disperse Red 1: Humidity-Driven Color Switching in Supramolecular Azo-Polymer Materials Based on Reversible Dye Aggregation.

PubMed

Schoelch, Simon; Vapaavuori, Jaana; Rollet, Frédéric-Guillaume; Barrett, Christopher J

2017-01-01

Humidity detection, and the quest for low-cost facile humidity-sensitive indicator materials is of great interest for many fields, including semi-conductor processing, food transport and storage, and pharmaceuticals. Ideal humidity-detection materials for a these applications might be based on simple clear optical readout with no power supply, i.e.: a clear color change observed by the naked eye of any untrained observer, since it doesn't require any extra instrumentation or interpretation. Here, the introduction of a synthesis-free one-step procedure, based on physical mixing of easily available commercial materials, for producing a humidity memory material which can be easily painted onto a wide variety of surfaces and undergoes a remarkable color change (approximately 100 nm blue-shift of λ MAX ) upon exposure to various thresholds of levels of ambient humidity is reported. This strong color change, easily visible to as a red-to-orange color switch, is locked in until inspection, but can then be restored reversibly if desired, after moderate heating. By taking advantage of spontaneously-forming reversible 'soft' supramolecular bonds between a red-colored azo dye and a host polymer matrix, a reversible dye 'migration' aggregation appearing orange, and dis-aggregation back to red can be achieved, to function as the sensor. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spectral relationships for atmospheric correction. I. Validation of red and near infra-red marine reflectance relationships.

PubMed

Goyens, C; Jamet, C; Ruddick, K G

2013-09-09

The present study provides an extensive overview of red and near infra-red (NIR) spectral relationships found in the literature and used to constrain red or NIR-modeling schemes in current atmospheric correction (AC) algorithms with the aim to improve water-leaving reflectance retrievals, ρw(λ), in turbid waters. However, most of these spectral relationships have been developed with restricted datasets and, subsequently, may not be globally valid, explaining the need of an accurate validation exercise. Spectral relationships are validated here with turbid in situ data for ρw(λ). Functions estimating ρw(λ) in the red were only valid for moderately turbid waters (ρw(λNIR) < 3.10(-3)). In contrast, bounding equations used to limit ρw(667) retrievals according to the water signal at 555 nm, appeared to be valid for all turbidity ranges presented in the in situ dataset. In the NIR region of the spectrum, the constant NIR reflectance ratio suggested by Ruddick et al. (2006) (Limnol. Oceanogr. 51, 1167-1179), was valid for moderately to very turbid waters (ρw(λNIR) < 10(-2)) while the polynomial function, initially developed by Wang et al. (2012) (Opt. Express 20, 741-753) with remote sensing reflectances over the Western Pacific, was also valid for extremely turbid waters (ρw(λNIR) > 10(-2)). The results of this study suggest to use the red bounding equations and the polynomial NIR function to constrain red or NIR-modeling schemes in AC processes with the aim to improve ρw(λ) retrievals where current AC algorithms fail.

Red and far-red fluorescent dyes for the characterization of head and neck cancer at the cellular level.

PubMed

Abbaci, Muriel; Casiraghi, Odile; Temam, Stephane; Ferchiou, Malek; Bosq, Jacques; Dartigues, Peggy; De Leeuw, Frederic; Breuskin, Ingrid; Laplace-Builhé, Corinne

2015-11-01

Primary upper aerodigestive tract malignancy remains a cancer having a poor prognosis, despite current progress in treatment, due to a generally late diagnosis. We conducted a preliminary assessment of five dyes approved for human use for the imaging of head and neck tissues at the cellular level, which could be considered for clinical examination. We investigated fluorescence endomicroscopic images on fresh samples obtained from head and neck surgeries after staining with hypericin, methylene blue, toluidine blue, patent blue or indocyanine green to provide a preliminary consideration as to whether these images contain enough information for identification of non-pathologic and pathologic tissues. The distribution pattern of dye has been examined using probe-based confocal laser endomicroscopy (pCLE) in ex vivo specimens and compared with corresponding histology. In most samples, the image quality provided by pCLE with both dyes allowed pathologists to recognize histological characteristics to identify the tissues. The combination of pCLE imaging with these dyes provides interpretable images close to conventional histology; a promising clinical tool to assist physicians in examination of upper aerodigestive tract, as long as depth imaging issues can be overcome. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of tannery sludge activated carbon and its utilization in the removal of azo reactive dye.

PubMed

Geethakarthi, A; Phanikumar, B R

2012-03-01

The removal of azo Reactive Red 31(RR31) from synthetic dye solution using tannery sludge-developed activated carbon (TSC) was investigated. TSC was prepared from a combination of physical and chemical activation. The developed TSC was characterized by FT-IR, SEM, TG-DTA, specific surface area and zero point charge of pH (pH(zpc)). The isotherm models, kinetic models and thermodynamic parameters were also analysed to describe the adsorptive behaviour of TSC. The effect of contact time, initial dye concentration, carbon dosage, agitation speed, initial pH and temperature were carried out for batch adsorption studies. The isotherm plot of the dye RR31 on TSC fitted better with the Langmuir adsorption isotherm than the Freundlich model. The maximum monolayer adsorption capacity of TSC in the removal of RR31 ranged from 23.15 to 39.37 mg/g. The thermodynamic parameters showed the endothermic and physical nature of the Reactive Red 31 adsorption on TSC. The entropy and enthalpy values were 181.515 J/Kmol and 5.285 kJ/mol, respectively. The developed cationic tannery sludge carbon was found to be an effective adsorbent in the removal of the anionic azo reactive dye RR31.

Bioremediation of direct dyes in simulated textile effluents by a paramorphogenic form of Aspergillus oryzae.

PubMed

Corso, C R; Almeida, E J R; Santos, G C; Morão, L G; Fabris, G S L; Mitter, E K

2012-01-01

Azo dyes are extensively used for coloring textiles, paper, food, leather, drinks, pharmaceutical products, cosmetics and inks. The textile industry consumes the largest amount of azo dyes, and it is estimated that approximately 10-15% of dyes used for coloring textiles may be lost in waste streams. Almost all azo dyes are synthetic and resist biodegradation, however, they can readily be reduced by a number of chemical and biological reducing systems. Biological treatment has advantages over physical and chemical methods due to lower costs and minimal environmental effect. This research focuses on the utilization of Aspergillus oryzae to remove some types of azo dyes from aqueous solutions. The fungus, physically induced in its paramorphogenic form (called 'pellets'), was used in the dye biosorption studies with both non-autoclaved and autoclaved hyphae, at different pH values. The goals were the removal of dyes by biosorption and the decrease of their toxicity. The dyes used were Direct Red 23 and Direct Violet 51. Their spectral stability (325-700 nm) was analyzed at different pH values (2.50, 4.50 and 6.50). The best biosorptive pH value and the toxicity limit, (which is given by the lethal concentration (LC(100)), were then determined. Each dye showed the same spectrum at different pH values. The best biosorptive pH was 2.50, for both non- autoclaved and autoclaved hyphae of A. oryzae. The toxicity level of the dyes was determined using the Trimmed Spearman-Karber Method, with Daphnia similis in all bioassays. The Direct Violet 51 (LC(100) 400 mg · mL(-1)) was found to be the most toxic dye, followed by the Direct Red 23 (LC(100) 900 mg · mL(-1)). The toxicity bioassays for each dye have shown that it is possible to decrease the toxicity level to zero by adding a small quantity of biomass from A. oryzae in its paramorphogenic form. The autoclaved biomass had a higher biosorptive capacity for the dye than the non-autoclaved biomass. The results show that bioremediation occurs with A. oryzae in its paramorphogenic form, and it can be used as a biosorptive substrate for treatment of industrial waste water containing azo dyes.

Sonochemical synthesis and structural characterization of a new Zn(II) nanoplate metal-organic framework with removal efficiency of Sudan red and Congo red.

PubMed

Abdollahi, Nasrin; Masoomi, Mohammad Yaser; Morsali, Ali; Junk, Peter C; Wang, Jun

2018-07-01

A 3-D Zn(II) based metal-organic framework (MOF) of [Zn 4 (oba) 3 (DMF) 2 ] was synthesized using the nonlinear dicarboxylate ligand, 4,4'-oxybis(benzoic acid) (H 2 oba) via sonochemical and solvothermal routes. IR spectroscopy, single-crystal X-ray crystallography, scanning electron microscopy, and X-ray powder diffraction were used to characterize these MOF samples. The effect of different times of irradiation and various concentrations of primary reagents were experimented for obtaining monotonous morphology. The results show that uniform nanoplates can be achieved by increasing the time of irradiation and decreasing the concentration. N 2 adsorption was applied to examine the effect of synthesis method on porosity of the framework. Also Congo red and Sudan red dyes were employed to explore the efficiency of this MOF in removal of the dye pollutants. Copyright © 2018 Elsevier B.V. All rights reserved.

Suppression of Red Blood Cell Autofluorescence for Immunocytochemistry on Fixed Embryonic Mouse Tissue.

PubMed

Whittington, Niteace C; Wray, Susan

2017-10-23

Autofluorescence is a problem that interferes with immunofluorescent staining and complicates data analysis. Throughout the mouse embryo, red blood cells naturally fluoresce across multiple wavelengths, spanning the emission and excitation spectra of many commonly used fluorescent reporters, including antibodies, dyes, stains, probes, and transgenic proteins, making it difficult to distinguish assay fluorescence from endogenous fluorescence. Several tissue treatment methods have been developed to bypass this issue with varying degrees of success. Sudan Black B dye has been commonly used to quench autofluorescence, but can also introduce background fluorescence. Here we present a protocol for an alternative called TrueBlack Lipofuscin Autofluorescence Quencher. The protocol described in this unit demonstrates how TrueBlack efficiently quenches red blood cell autofluorescence across red and green wavelengths in fixed embryonic tissue without interfering with immunofluorescent signal intensity or introducing background staining. We also identify optimal incubation, concentration, and multiple usage conditions for routine immunofluorescence microscopy. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

Enhanced adsorption of methyl violet and congo red by using semi and full IPN of polymethacrylic acid and chitosan.

PubMed

Maity, Jayabrata; Ray, Samit Kumar

2014-04-15

Semi and full interpenetrating polymer network (IPN) type hydrogels were prepared by free radical in situ polymerization of methacrylic acid in presence of chitosan using N,N'-methylene-bis-acrylamide (MBA) and glutaraldehyde (for full IPN) as crosslinker. Several semi and full IPN type hydrogels were prepared by varying initiator and crosslinker concentration and also monomer to chitosan mass ratio. These hydrogels were characterized and used for removal of methyl violet and congo red dye from water. Isotherms and kinetics of dye adsorption were also evaluated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ultra-Bright and -Stable Red and Near-Infrared Squaraine Fluorophores for In Vivo Two-Photon Imaging

PubMed Central

Podgorski, Kaspar; Terpetschnig, Ewald; Klochko, Oleksii P.; Obukhova, Olena M.; Haas, Kurt

2012-01-01

Fluorescent dyes that are bright, stable, small, and biocompatible are needed for high-sensitivity two-photon imaging, but the combination of these traits has been elusive. We identified a class of squaraine derivatives with large two-photon action cross-sections (up to 10,000 GM) at near-infrared wavelengths critical for in vivo imaging. We demonstrate the biocompatibility and stability of a red-emitting squaraine-rotaxane (SeTau-647) by imaging dye-filled neurons in vivo over 5 days, and utility for sensitive subcellular imaging by synthesizing a specific peptide-conjugate label for the synaptic protein PSD-95. PMID:23251670

Theoretical Study of Electron Transfer Properties of Squaraine Dyes for Dye Sensitized Solar Cell

NASA Astrophysics Data System (ADS)

Juwita, Ratna; Tsai, Hui-Hsu Gavin

2018-01-01

The environmental issues and high cost of Ru create many scientists to explore cheaper and safer sensitizer as alternative for dye sensitized solar cells (DSCs). Dyes play an important role in solar energy conversion efficiency. The squaraine (SQ) dyes has good spectral match with the solar spectra, therefore, SQ dyes have great potential for the applications in DSCs. SQ01_CA is an unsymmetrical SQ dye, reported by Grätzel and colleagues in 2007, featuring a D-π-spacer-A framework and has a carboxylic acid anchoring group. The electron donating ability of indolium in SQ01_CA and SQ01_CAA dyes is relatively weak, better performance may be achieved by introducing an additional donor moiety into indolium [1]. In this study, we investigate six unsymmetrical SQ dyes adsorbed on a (TiO2)38 cluster [2] using density functional theory (DFT) and time-dependent DFT to study electron transfer properties of squaraine dyes on their photophysical. SQ01_CA, WH-SQ01_CA, and WH-SQ02_CA use a carboxylic acid group as its electron acceptor. Furthermore, SQ01_CAA, WH-SQ01_CAA, and WH-SQ02_CAA use a cyanoacrylic acid group as its electron acceptor. WH-SQ01_CA and WH-SQ01_CAA have an alkyl, while WH-SQ02_CA and WH-SQ02_CAA have alkoxyl substituted diarylamines to the indolium donor of sensitizer SQ01_CA. Our calculations show with additional diarylamines in donor tail of WH-SQ02_CAA, the SQ dyes have red-shifted absorption and have slightly larger probability of electron density transferred to TiO2 moiety. Furthermore, an additional -CN group as electron a withdrawing group in the acceptor exhibits red-shifted absorption and enhances the electron density transferred to TiO2 and anchoring moiety after photo-excitation. The tendency of calculated probabilities of electron density being delocalized into TiO2 and driving force for excited-state electron injection of these studied SQ dyes is compatible with their experimentally observed.

Preparation of surface modified zinc oxide nanoparticle with high capacity dye removal ability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahmoodi, Niyaz Mohammad, E-mail: nm_mahmoodi@yahoo.com; Najafi, Farhood

2012-07-15

Highlights: ► Amine-functionalized zinc oxide nanoparticle (AFZON) was synthesized. ► Isotherm and kinetics data followed Langmuir isotherm and pseudo-second order kinetic model, respectively. ► Q{sub 0} of ZON for AB25, DR23 and DR31 was 20, 12 and 15 mg/g, respectively. ► Q{sub 0} of AFZON for AB25, DR23 and DR31 was 1250, 1000 and 1429 mg/g, respectively. ► AFZON was regenerated at pH 12. -- Abstract: In this paper, the surface modification of zinc oxide nanoparticle (ZON) by amine functionalization was studied to prepare high capacity adsorbent. Dye removal ability of amine-functionalized zinc oxide nanoparticle (AFZON) and zinc oxide nanoparticlemore » (ZON) was also investigated. The physical characteristics of AFZON were studied using Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Acid Blue 25 (AB25), Direct Red 23 (DR23) and Direct Red 31 (DR31) were used as model compounds. The effect of operational parameters such as dye concentration, adsorbent dosage, pH and salt on dye removal was evaluated. The isotherm and kinetic of dye adsorption were studied. The maximum dye adsorption capacity (Q{sub 0}) was 20 mg/g AB25, 12 mg/g DR23 and 15 mg/g DR31 for ZON and 1250 mg/g AB25, 1000 mg/g DR23 and 1429 mg/g DR31 for AFZON. It was found that dye adsorption followed Langmuir isotherm. Adsorption kinetic of dyes was found to conform to pseudo-second order kinetics. Dye desorption tests (adsorbent regeneration) showed that the maximum dye release of 90% AB25, 86% for DR23 and 90% for DR31 were achieved in aqueous solution at pH 12. Based on the data of the present investigation, it can be concluded that the AFZON being an adsorbent with high dye adsorption capacity might be a suitable alternative to remove dyes from colored aqueous solutions.« less

Chitosan-edible oil based materials as upgraded adsorbents for textile dyes.

PubMed

Dos Santos, Clayane Carvalho; Mouta, Rodolpho; Junior, Manoel Carvalho Castro; Santana, Sirlane Aparecida Abreu; Silva, Hildo Antonio Dos Santos; Bezerra, Cícero Wellington Brito

2018-01-15

Biopolymer chitosan is a low cost, abundant, environmentally friendly, very selective and efficient anionic dyes adsorbent, being a promising material for large-scale removal of dyes from wastewater. However, raw chitosan (CS) is an ineffective cationic dyes adsorbent and its performance is pH sensitive, thus, CS modifications that address these issues need to be developed. Here, we report the preparation and characterization of two new CS modifications using edible oils (soybean oil or babassu oil), and their adsorption performance for two dyes, one anionic (remazol red, RR) and one cationic (methylene blue, MB). Both modifications extended the pH range of RR adsorption. The babassu oil modification increased adsorption capacity of the cationic dye MB, whereas the soybean oil modification increased that of RR. Such improvements demonstrate the potential of these two new CS modifications as adsorbent candidates for controlling dyes pollution in effluents. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of coloring efficacy of lac dye in comminuted meat product.

PubMed

Divya; Singh, R P; Baboo, B; Prasad, K M

2011-06-01

Effect of incorporation of graded levels (4, 6, 8, 10, 25 ppm) of lac dye on coloring efficacy and possible use of this natural color in processed meat products was studied. Inclusion of lac dye at different concentrations did not affect the pH significantly whereas a linear increase in the Lovibond red color unit of chicken nuggets was noted with raising the level of lac dye from 4 to 10 ppm. The sensory rating for color was highest at addition level of 25 ppm of lac dye and it was comparable to color score of the product containing 200 ppm sodium nitrite. Lac dye inclusion in nuggets at all concentrations studied had better antimicrobial properties as compared to 200 ppm sodium nitrite. It was concluded that lac dye from 10 to 25 ppm could be incorporated in comminuted meat products as a natural colorant with antimicrobial action.

Potentiometric Dye Imaging for Pheochromocytoma and Cortical Neurons with a Novel Measurement System Using an Integrated Complementary Metal-Oxide-Semiconductor Imaging Device

NASA Astrophysics Data System (ADS)

Kobayashi, Takuma; Tagawa, Ayato; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Hatanaka, Yumiko; Tamura, Hideki; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun

2010-11-01

The combination of optical imaging with voltage-sensitive dyes is a powerful tool for studying the spatiotemporal patterns of neural activity and understanding the neural networks of the brain. To visualize the potential status of multiple neurons simultaneously using a compact instrument with high density and a wide range, we present a novel measurement system using an implantable biomedical photonic LSI device with a red absorptive light filter for voltage-sensitive dye imaging (BpLSI-red). The BpLSI-red was developed for sensing fluorescence by the on-chip LSI, which was designed by using complementary metal-oxide-semiconductor (CMOS) technology. A micro-electro-mechanical system (MEMS) microfabrication technique was used to postprocess the CMOS sensor chip; light-emitting diodes (LEDs) were integrated for illumination and to enable long-term cell culture. Using the device, we succeeded in visualizing the membrane potential of 2000-3000 cells and the process of depolarization of pheochromocytoma cells (PC12 cells) and mouse cerebral cortical neurons in a primary culture with cellular resolution. Therefore, our measurement application enables the detection of multiple neural activities simultaneously.

In vivo multispectral photoacoustic and photothermal flow cytometry with multicolor dyes: a potential for real-time assessment of circulation, dye-cell interaction, and blood volume

PubMed Central

Proskurnin, Mikhail A.; Zhidkova, Tatyana V.; Volkov, Dmitry S.; Sarimollaoglu, Mustafa; Galanzha, Ekaterina I.; Mock, Donald; Zharov, Vladimir P.

2011-01-01

Recently, photoacoustic (PA) flow cytometry (PAFC) has been developed for in vivo detection of circulating tumor cells and bacteria targeted by nanoparticles. Here, we propose multispectral PAFC with multiple dyes having distinctive absorption spectra as multicolor PA contrast agents. As a first step of our proof-of-concept, we characterized high-speed PAFC capability to monitor the clearance of three dyes (ICG, MB, and TB) in an animal model in vivo and in real time. We observed strong dynamic PA signal fluctuations, which can be associated with interactions of dyes with circulating blood cells and plasma proteins. PAFC demonstrated enumeration of circulating red and white blood cells labeled with ICG and MB, respectively, and detection of rare dead cells uptaking TB directly in bloodstream. The possibility for accurate measurements of various dye concentrations including CV and BG were verified in vitro using complementary to PAFC photothermal (PT) technique and spectrophotometry under batch and flow conditions. We further analyze the potential of integrated PAFC/PT spectroscopy with multiple dyes for rapid and accurate measurements of circulating blood volume without a priori information on hemoglobin content, which is impossible with existing optical techniques. This is important in many medical conditions including surgery and trauma with extensive blood loss, rapid fluid administration, transfusion of red blood cells. The potential for developing a robust clinical PAFC prototype that is, safe for human, and its applications for studying the liver function are further highlighted. PMID:21905207

Red light regulation of ethylene biosynthesis and gravitropism in etiolated pea stems

NASA Technical Reports Server (NTRS)

Steed, C. L.; Taylor, L. K.; Harrison, M. A.

2004-01-01

During gravitropism, the accumulation of auxin in the lower side of the stem causes increased growth and the subsequent curvature, while the gaseous hormone ethylene plays a modulating role in regulating the kinetics of growth asymmetries. Light also contributes to the control of gravitropic curvature, potentially through its interaction with ethylene biosynthesis. In this study, red-light pulse treatment of etiolated pea epicotyls was evaluated for its effect on ethylene biosynthesis during gravitropic curvature. Ethylene biosynthesis analysis included measurements of ethylene; the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC); malonyl-conjugated ACC (MACC); and expression levels of pea ACC oxidase (Ps-ACO1) and ACC synthase (Ps-ACS1, Ps-ACS2) genes by reverse transcriptase-polymerase chain reaction analysis. Red-pulsed seedlings were given a 6 min pulse of 11 micromoles m-2 s-1 red-light 15 h prior to horizontal reorientation for consistency with the timeline of red-light inhibition of ethylene production. Red-pulse treatment significantly reduced ethylene production and MACC levels in epicotyl tissue. However, there was no effect of red-pulse treatment on ACC level, or expression of ACS or ACO genes. During gravitropic curvature, ethylene production increased from 60 to 120 min after horizontal placement in both control and red-pulsed epicotyls. In red-pulsed tissues, ACC levels increased by 120 min after horizontal reorientation, accompanied by decreased MACC levels in the lower portion of the epicotyl. Overall, our results demonstrate that ethylene production in etiolated epicotyls increases after the initiation of curvature. This ethylene increase may inhibit cell growth in the lower portion of the epicotyl and contribute to tip straightening and reduced overall curvature observed after the initial 60 min of curvature in etiolated pea epicotyls.

Electrical and Luminescent Properties of Color-Changeable Organic Electroluminescent Diode Using Squarylium Dyes

NASA Astrophysics Data System (ADS)

Mori, Tatsuo; Miyachi, Kiyokazu; Kichimi, Tomoaki; Mizutani, Teruyoshi

1994-12-01

The organic electoluminescent diode (LED) with squarylium (Sq) dye-doped Alq3 changes color upon application of voltage (current). The luminescent color from the organic LED changes from red (electroluminescence (EL) of Sq dye) at low voltage to light green (EL of Alq3) at high voltage. We studied the EL efficiency and EL spectrum of organic Sq-doped Alq3 LED with various doping positions in the emission layer. Consequentially, it was clarified that Sq doping near TPD considerably reduced the EL efficiency. The EL mechanism of the organic LED was concluded to be associated with the energy transfer from the excited Alq3 to the guest dye and hole trapping of the guest dye in Alq3.

The influence of the distance between the donor-acceptor groups of polymethine dyes on their photovoltaic properties

NASA Astrophysics Data System (ADS)

Seliverstova, E.; Ibrayev, N.

2018-01-01

Spectral-luminescent and photovoltaic properties of polymethine dyes of various structures are studied. It is shown that an increase in the length of the methylene chain between the active chromophores leads to a red-wave shift of the absorption and fluorescence spectra. Significant changes in the absorptivity and lifetime of fluorescence do not occur in this case. The best photovoltaic parameters have cells sensitized with shorter dye molecules. It is shown, that for a longer dye the resistance associated with electron recombination on the TiO2/electrolyte surface is much higher than the electron transfer resistance in the semiconductor, which reduces the efficiency of electron transfer in the solar cell, sensitized with longer dye molecules.

Electromagnetic Radiation: Final Range Environmental Assessment, Revision 1

DTIC Science & Technology

2009-12-03

scanning, research, and medical treatment and surgical procedures. There are many different types of lasing materials as identified below ( Indiana ...vapor (red) 0.627 Xenon chloride (Excimer-UV) 0.308 Helium neon (red) 0.633 Xenon fluoride (Excimer-UV) 0.351 Krypton (red) 0.647 Helium cadmium (UV...0.325 Rhodamine 6G dye (tunable) 0.570-0.650 Nitrogen (UV) 0.337 Ruby (CrAlO3) (red) 0.694 Helium cadmium (violet) 0.441 Gallium arsenide (diode

Characterisation of novel pH indicator of natural dye Oldenlandia umbellata L.

PubMed

Ramamoorthy, Siva; Mudgal, Gaurav; Rajesh, D; Nawaz Khan, F; Vijayakumar, V; Rajasekaran, C

2009-01-01

Oldenlandia umbellata L., commonly known as 'chay root', belongs to the family Rubiaceae and is one of the unexplored dye-yielding plants. The roots from this plant are the sources of red dye. Extraction protocol and dye characterisation have not been completely studied so far in this plant. Hence, in this article we have used UV spectrophotometry, thin layer chromatography, GC-MS, high-performance liquid chromatography and NMR to identify the five major colouring compounds, including 1,2,3-trimethoxyanthraquinone, 1,3-dimethoxy-2-hydroxyanthraquinone, 1,2-dimethoxyanthraquinone, 1-methoxy-2-hydroxyanthraquinone and 1,2-dihydroxyanthraquinone. It showed application feasibility as a new pH indicator.

Razor clam (Ensis directus) shell as a low-cost adsorbent for the removal of Congo red and Rhodamine B dyes from aqueous solution

NASA Astrophysics Data System (ADS)

Areibat, Lila Elamari Mohamed; Kamari, Azlan

2017-05-01

Wastewater originating from industrial effluents contains many types of pollutants including dyes. Anionic and cationic dyes are very toxic and they can cause several problems to aquatic system. In present study, razor clam shell was used as a potential adsorbent to remove two classes of dyes, namely anionic (Congo red, CR) and cationic (Rhodamine B, RB) dyes from aqueous solution. Batch adsorption experiments were performed to study the effects of three experimental parameters, namely solution pH, adsorbent dosage and initial dye concentration, on adsorption capacity of CR and RB onto razor clam shell. Results indicated that pH 2.0 was optimum pH for adsorbent to adsorb both CR and RB. At an initial concentration of 20 mg/L, the removal percentages of CR and RB were 97% and 38%, respectively. The Freundlich and Langmuir isotherm models were used to describe adsorption behaviour of CR and RB, as well as the relationship between adsorbent and adsorbate. The adsorption equilibrium data were well fitted to Freundlich isotherm model. The separation factor (RL) constants suggest that both CR and RB were favourably adsorbed by razor clam shell. Razor clam shell was characterised by using two techniques, namely Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectrometry (FTIR). Overall, this study suggests that razor clam shell has great potential to be an alternative to expensive adsorbents.

Photo-degradation of basic green 1 and basic red 46 dyes in their binary solution by La2O3-Al2O3nanocomposite using first-order derivative spectra and experimental design methodology.

PubMed

Fahimirad, Bahareh; Asghari, Alireza; Rajabi, Maryam

2017-05-15

In this work, the lanthanum oxide-aluminum oxide (La 2 O 3 -Al 2 O 3 ) nanocomposite is introduced as an efficient photocatalyst for the photo-degradation of the dyes basic green 1 (BG1) and basic red 46 (BR46) in their binary aqueous solution under the UV light irradiation. The properties of this catalyst are determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET), and UV-visible spectrophotometry. The first-order derivative spectra are used for the simultaneous analysis of the dyes in their binary solution. The screening investigations indicate that five parameters including the catalyst dosage, concentration of the dyes, irradiation time, and solution pH have significant effects on the photo-degradation of the dyes. The effects of these variables together with their interactions in the photo-degradation of the dyes are studied using the Box-Behnken design (BBD). Under the optimum experimental conditions, obtained via the desirability function, the photo-catalytic activities of La 2 O 3 -Al 2 O 3 and pure Al 2 O 3 are also investigated. The results obtained show an enhancement in the photo-catalytic activity when La 2 O 3 nanoparticles are loaded on the surface of Al 2 O 3 nanoparticles. Copyright © 2017 Elsevier B.V. All rights reserved.

Anthocyanin – Rich Red Dye of Hibiscus Sabdariffa Calyx Modulates Cisplatin-induced Nephrotoxicity and Oxidative Stress in Rats

PubMed Central

Ademiluyi, Adedayo O.; Oboh, Ganiyu; Agbebi, Oluwaseun J.; Akinyemi, Ayodele J.

2013-01-01

This study sought to investigate the protective effect of dietary inclusion of Hibiscus sabdariffa calyx red dye on cisplatin-induced nephrotoxicity and antioxidant status in rats. Adult male rats were randomly divided into four groups of six animals each. Groups I and II were fed basal diet while groups III and IV were fed diets containing 0.5% and 1% of the dye respectively for 20 days prior to cisplatin administration. Nephrotoxicity was induced by a single dose intraperitoneal administration of cisplatin (7 mg/kg b.w) and the experiment was terminated 3 days after. The kidney and plasma were studied for nephrotoxicity and oxidative stress indices. Cisplatin administration caused a significant (P<0.05) increase in creatinine, uric acid, urea, and blood urea nitrogen (BUN) levels as well as kidney malondialdehyde (MDA) content, with concomitant decrease in kidney vitamin C and GSH contents. Furthermore, activities of kidney antioxidant enzymes such as, SOD, Catalase, and GST were significantly (P<0.05) altered in cisplatin administered rats. However, consumption of diets supplemented with the dye for 20 days prior to cisplatin administration protected the kidney and attenuates oxidative stress through modulation of in vivo antioxidant status. The determined anthocyanin content of the dye is 121.5 mg Cyanidin-3-rutinoside equivalent/100 g, thus, the observed nephroprotective effect of H. sabdariffa dye could be attributed to its anthocyanin content. PMID:24711761

Assessment of FUN-1 vital dye staining: Yeast with a block in the vacuolar sorting pathway have impaired ability to form CIVS when stained with FUN-1 fluorescent dye.

PubMed

Essary, Brandin D; Marshall, Pamela A

2009-08-01

FUN-1 [2-chloro-4-(2,3-dihydro-3-methyl-(benzo-1,3-thiazol-2-yl)-methylidene)-1-phenylquinolinium iodide] is a fluorescent dye used in studies of yeast and other fungi to monitor cell viability in the research lab and to assay for active fungal infection in the clinical setting. When the plasma membrane is intact, fungal cells internalize FUN-1 and the dye is seen as diffuse green cytosolic fluorescence. FUN-1 is then transported to the vacuole in metabolically active wild type cells and subsequently is compacted into fluorescent red cylindrical intravacuolar structures (CIVS) by an unknown transport pathway. This dye is used to determine yeast viability, as only live cells form CIVS. However, in live Saccharomyces cerevisiae with impaired protein sorting to the yeast vacuole, we report decreased to no CIVS formation, depending on the cellular location of the block in the sorting pathway. Cells with a block in vesicle-mediated transport from the Golgi to prevacuolar compartment (PVC) or with a block in recycling from the PVC to the Golgi demonstrate a substantial impairment in CIVS formation. Instead, the FUN-1 dye is seen either in small punctate structures under fluorescence or as diffuse red cytosol under white light. Thus, researchers using FUN-1 should be cognizant of the limitations of this procedure in determining cell viability as there are viable yeast mutants with impaired CIVS formation.

Photoinduced intramolecular charge transfer in a cross-conjugated push-pull enediyne: implications toward photoreaction.

PubMed

Singh, Anuja; Pati, Avik Kumar; Mishra, Ashok Kumar

2018-05-30

Push-pull organic fluorophores are important owing to their interesting optoelectronical properties. Here we report the photophysics of a new cross-conjugated push-pull enediynyl dye which belongs to an unexplored class of π-conjugated donor-acceptor systems. Two N,N-dimethylaniline moieties serve as donors and one pyrene ring functions as an acceptor via a common Y-shaped 'enediyne' bridge which facilitates the cross-electronic communication. The dye exhibits dual emission from locally excited (LE) and intramolecular charge transfer (ICT) states. While the LE emission is dominant in non-polar solvents, the ICT emission predominates in polar solvents. Time-resolved fluorescence decay experiments reveal a relatively shorter lifetime component (∼0.5-0.9 ns) belonging to an ICT state and a relatively longer lifetime species (∼1.6-2.8 ns) corresponding to the LE state. The strong ICT behavior of the dye is manifested through the huge red-shift (4166 cm-1) of the emission spectra from non-polar cyclohexane to polar N,N-dimethylformamide. In contrast to many small push-pull organic dyes, the LE and ICT states of the push-pull enediynyl dye follow the same excitation pathway. The dominant red-shifted ICT emission (∼550 nm) intensity of the dye in polar solvent decreases with a concomitant appearance of the blue-shifted LE emission (∼385 nm) upon prolonged exposure to photons. This opens up a new photophysical strategy of achieving high contrast two fluorescence color conversion from yellow to blue.

Melamine-formaldehyde microcapsules filled sappan dye modified polypropylene composites: encapsulation and thermal properties

NASA Astrophysics Data System (ADS)

Phanyawong, Suphitcha; Siengchin, Suchart; Parameswaranpillai, Jyotishkumar; Asawapirom, Udom; Polpanich, Duangporn

2018-01-01

Sappan dye, a natural dye extracted from sappan wood is widely used in cosmetics, textile dyeing and as food additives. However, it was recognized that natural dyes cannot withstand high temperature. In this study, a protective coating of melamine-formaldehyde shell material was applied over the sappan dye to improve its thermal stability. The percentage of sappan dye used in the microencapsulation was 30, 40, 50, 60 and 70 wt%. The color, shape, size, and thermal stability of sappan dye microcapsules were investigated. It was found that increasing amount of sappan dye content in the microcapsules decreased the particle size. Thermal analysis reveals that the melamine-formaldehyde resin served as an efficient protective shell for sappan dye. Besides, 30 wt% sappan dye microcapsules with different weight percent (1, 3 and 5 wt%) of sappan dye was used as modifier for polypropylene (PP). All the prepared composites are red in color which supports the thermal stability of the microcapsules. The changes in crystallinity and melting behavior of PP by the addition of microcapsules were studied in detail by differential scanning calorimetry. Thermogravimetric studies showed that the thermal stability of PP composites increased by the addition of microcapsules.

Sonochemical assisted hydrothermal synthesis of ZnO: Cr nanoparticles loaded activated carbon for simultaneous ultrasound-assisted adsorption of ternary toxic organic dye: Derivative spectrophotometric, optimization, kinetic and isotherm study.

PubMed

Jamshidi, M; Ghaedi, M; Dashtian, K; Hajati, S; Bazrafshan, A A

2016-09-01

Chromium doped zinc oxide nanoparticles (ZnO: Cr-NPs) was synthesized by ultrasonically assisted hydrothermal method and characterized by FE-SEM, XRD and TEM analysis. Subsequently, this composite ultrasonically assisted was deposited on activated carbon (ZnO: Cr-NPs-AC) and used for simultaneous ultrasound-assisted removal of three toxic organic dye namely of malachite green (MG), eosin yellow (EY) and Auramine O (AO). Dyes spectra overlap in mixture (major problem for simultaneous investigation) of this systems was extensively resolved by derivative spectrophotometric method. The magnitude of variables like initial dyes concentration, adsorbent mass and sonication time influence on dyes removal was optimized using small central composite design (CCD) combined with desirability function (DF) approach, while pH was studied by one-a-time approach. The maximized removal percentages at desirability of 0.9740 was set as follow: pH 6.0, 0.019g ZnO: Cr-NPs-AC, 3.9min sonication at 4.5, 4.8 and 4.7mgL(-1) of MG, EY and AO, respectively. Above optimized points lead to achievement of removal percentage of 98.36%, 97.24%, and 99.26% correspond to MG, EY and AO, respectively. ANOVA for each dyes based p-value less than (<0.0001) suggest highly efficiency of CCD model for prediction of data concern to simultaneous removal of these dyes within 95% confidence interval, while their F-value for MG, EY and AO is 935, 800.2, and 551.3, respectively, that confirm low participation of this them in signal. The value of multiple correlation coefficient R(2), adjusted and predicted R(2) for simultaneous removal of MG is 0.9982, 0.9972 and 0.9940, EY is 0.9979, 0.9967 and 0.9930 and for AO is 0.9970, 0.9952 and 0.9939. The adsorption rate well fitted by pseudo second-order and Langmuir model via high, economic and profitable adsorption capacity of 214.0, 189.7 and 211.6mgg(-1) for MG, EY and AO, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Multilayer Dye Aggregation at Dye/TiO2 Interface via π…π Stacking and Hydrogen Bond and Its Impact on Solar Cell Performance: A DFT Analysis.

PubMed

Zhang, Lei; Liu, Xiaogang; Rao, Weifeng; Li, Jingfa

2016-10-21

Multilayer dye aggregation at the dye/TiO 2 interface of dye-sensitized solar cells is probed via first principles calculations, using p-methyl red azo dye as an example. Our calculations suggest that the multilayer dye aggregates at the TiO 2 surface can be stabilized by π…π stacking and hydrogen bond interactions. Compared with previous two-dimensional monolayer dye/TiO 2 model, the multilayer dye aggregation model proposed in this study constructs a three-dimensional multilayer dye/TiO 2 interfacial structure, and provides a better agreement between experimental and computational results in dye coverage and dye adsorption energy. In particular, a dimer forms by π…π stacking interactions between two neighboring azo molecules, while one of them chemisorbs on the TiO 2 surface; a trimer may form by introducing one additional azo molecule on the dimer through a hydrogen bond between two carboxylic acid groups. Different forms of multilayer dye aggregates, either stabilized by π…π stacking or hydrogen bond, exhibit varied optical absorption spectra and electronic properties. Such variations could have a critical impact on the performance of dye sensitized solar cells.

Multilayer Dye Aggregation at Dye/TiO2 Interface via π…π Stacking and Hydrogen Bond and Its Impact on Solar Cell Performance: A DFT Analysis

PubMed Central

Zhang, Lei; Liu, Xiaogang; Rao, Weifeng; Li, Jingfa

2016-01-01

Multilayer dye aggregation at the dye/TiO2 interface of dye-sensitized solar cells is probed via first principles calculations, using p-methyl red azo dye as an example. Our calculations suggest that the multilayer dye aggregates at the TiO2 surface can be stabilized by π…π stacking and hydrogen bond interactions. Compared with previous two-dimensional monolayer dye/TiO2 model, the multilayer dye aggregation model proposed in this study constructs a three-dimensional multilayer dye/TiO2 interfacial structure, and provides a better agreement between experimental and computational results in dye coverage and dye adsorption energy. In particular, a dimer forms by π…π stacking interactions between two neighboring azo molecules, while one of them chemisorbs on the TiO2 surface; a trimer may form by introducing one additional azo molecule on the dimer through a hydrogen bond between two carboxylic acid groups. Different forms of multilayer dye aggregates, either stabilized by π…π stacking or hydrogen bond, exhibit varied optical absorption spectra and electronic properties. Such variations could have a critical impact on the performance of dye sensitized solar cells. PMID:27767196

Heat-induced formation of a specific binding site for self-assembled Congo Red in the V domain of immunoglobulin L chain lambda.

PubMed

Piekarska, B; Konieczny, L; Rybarska, J; Stopa, B; Zemanek, G; Szneler, E; Król, M; Nowak, M; Roterman, I

2001-11-01

Moderate heating (40-50 degrees C) of immunoglobulins makes them accessible for binding with Congo Red and some related highly associated dyes. The binding is specific and involves supramolecular dye ligands presenting ribbon-like micellar bodies. The L chain lambda dimer, which upon heating disclosed the same binding requirement with respect to supramolecular dye ligands, was used in this work to identify the site of their attachment. Two clearly defined dye-protein (L lambda chain) complexes arise upon heating, here called complex I and complex II. The first is formed at low temperatures (up to 40-45 degrees C) and hence by a still native protein, while the formation of the second one is associated with domain melting above 55 degrees C. They contain 4 and 8 dye molecules bound per L chain monomer, respectively. Complex I also forms efficiently at high dye concentration even at ambient temperature. Complex I and its formation was the object of the present studies. Three structural events that could make the protein accessible to penetration by the large dye ligand were considered to occur in L chains upon heating: local polypeptide chain destabilization, VL-VL domain incoherence, and protein melting. Of these three possibilities, local low-energy structural alteration was found to correlate best with the formation of complex I. It was identified as decreased packing stability of the N-terminal polypeptide chain fragment, which as a result made the V domain accessible for dye penetration. The 19-amino acid N-terminal fragment becomes susceptible to proteolytic cleavage after being replaced by the dye at its packing locus. Its splitting from the dye-protein complex was proved by amino acid sequence analysis. The emptied packing locus, which becomes the site that holds the dye, is bordered by strands of amino acids numbered 74-80 and 105-110, as shown by model analysis. The character of the temperature-induced local polypeptide chain destabilization and its possible role in intramolecular antibody signaling is discussed. Copyright 2001 John Wiley & Sons, Inc.

Ultrasonic enhancement of the simultaneous removal of quaternary toxic organic dyes by CuO nanoparticles loaded on activated carbon: Central composite design, kinetic and isotherm study.

PubMed

Dashamiri, Somayeh; Ghaedi, Mehrorang; Dashtian, Kheibar; Rahimi, Mahmood Reza; Goudarzi, Alireza; Jannesar, Ramin

2016-07-01

Copper oxide nanoparticles loaded on activated carbon (CuO-NPs-AC) were prepared and fully analyzed and characterized with FE-SEM, XRD and FT-IR. Subsequently, this novel material was used for simultaneous ultrasound-assisted adsorption of brilliant green (BG), auramine O (AO), methylene blue (MB) and eosin yellow (EY) dyes. Problems regard to dyes spectra overlap in quaternary solution of this dyes were omitted by derivative spectrophotometric method. The best pH in quaternary system was studied by using one at a time method to achieved maximum dyes removal percentage. Subsequently, sonication time, adsorbent dosage and initial dyes concentrations influence on dyes removal was optimized by central composite design (CCD) combined with desirability function approach (DFA). Desirability score of 0.978 show optimum conditions set at sonication time (4.2 min), adsorbent mass (0.029 g), initial dyes concentration (4.5 mg L(-1)). Under this optimum condition the removal percentage for MB, AO, EY and BG dyes 97.58, 94.66, 96.22 and 94.93, respectively. The adsorption rate well fitted by pseudo second-order while adsorption capacity according to the Langmuir model as best equilibrium isotherm model for BG, MB, AO and EY was 20.48, 21.26, 22.34 and 21.29 mg g(-1), respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Equilibrium, kinetics and process design of acid yellow 132 adsorption onto red pine sawdust.

PubMed

Can, Mustafa

2015-01-01

Linear and non-linear regression procedures have been applied to the Langmuir, Freundlich, Tempkin, Dubinin-Radushkevich, and Redlich-Peterson isotherms for adsorption of acid yellow 132 (AY132) dye onto red pine (Pinus resinosa) sawdust. The effects of parameters such as particle size, stirring rate, contact time, dye concentration, adsorption dose, pH, and temperature were investigated, and interaction was characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscope. The non-linear method of the Langmuir isotherm equation was found to be the best fitting model to the equilibrium data. The maximum monolayer adsorption capacity was found as 79.5 mg/g. The calculated thermodynamic results suggested that AY132 adsorption onto red pine sawdust was an exothermic, physisorption, and spontaneous process. Kinetics was analyzed by four different kinetic equations using non-linear regression analysis. The pseudo-second-order equation provides the best fit with experimental data.

Near-infrared sensitization in dye-sensitized solar cells.

PubMed

Park, Jinhyung; Viscardi, Guido; Barolo, Claudia; Barbero, Nadia

2013-01-01

Dye-sensitized solar cells (DSCs) are a low cost and colorful promising alternative to standard silicon photovoltaic cells. Though many of the highest efficiencies have been associated with sensitizers absorbing only in the visible portion of the solar radiation, there is a growing interest for NIR sensitization. This paper reviews the efforts made so far to find sensitizers able to absorb efficiently in the far-red NIR region of solar light. Panchromatic sensitizers as well as dyes absorbing mainly in the 650-920 nm region have been considered.

Ultra-bright red-emitting photostable perylene bisimide dyes: new indicators for ratiometric sensing of high pH or carbon dioxide.

PubMed

Pfeifer, David; Klimant, Ingo; Borisov, Sergey M

2018-05-08

New pH sensitive perylene bisimide indicator dyes were synthesised and used for fabrication of optical sensors. The highly photostable dyes show absorption/emission bands in the red/near-infrared (NIR) region of the electromagnetic spectrum, high molar absorption coefficients (up to 100 000 M-1 cm-1) and fluorescence quantum yields close to unity. The absorption and emission spectra show strong bathochromic shift upon deprotonation of imidazole nitrogen which makes the dyes promising as ratiometric fluorescent indicators. Physical entrapment of the indicators into polyurethane hydrogel enables pH determination in alkaline pH. It is also shown that plastic carbon dioxide solid state sensor can be manufactured via immobilization of the pH indicator in a hydrophilic polymer, along with a quaternary ammonium base. The influence of plasticizer, different lipophilic bases and humidity on the sensitivity of the sensor material were systematically investigated. The disubstituted perylene, particularly, features two deprotonation equilibria enabling sensing over a very broad range from 0.5 to 1000 hPa pCO2. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Trichocyanines: a Red-Hair-Inspired Modular Platform for Dye-Based One-Time-Pad Molecular Cryptography.

PubMed

Leone, Loredana; Pezzella, Alessandro; Crescenzi, Orlando; Napolitano, Alessandra; Barone, Vincenzo; d'Ischia, Marco

2015-06-01

Current molecular cryptography (MoCryp) systems are almost exclusively based on DNA chemistry and reports of cryptography technologies based on other less complex chemical systems are lacking. We describe herein, as proof of concept, the prototype of the first asymmetric MoCryp system, based on an 8-compound set of a novel bioinspired class of cyanine-type dyes called trichocyanines. These novel acidichromic cyanine-type dyes inspired by red hair pigments were synthesized and characterized with the aid of density functional theory (DFT) calculations. Trichocyanines consist of a modular scaffold easily accessible via an expedient condensation of 3-phenyl- or 3-methyl-2H-1,4-benzothiazines with N-dimethyl- or o-methoxyhydroxy-substituted benzaldehyde or cinnamaldehyde derivatives. The eight representative members synthesized herein can be classified as belonging to two three-state systems tunable through four different control points. This versatile dye platform can generate an expandable palette of colors and appears to be specifically suited to implement an unprecedented single-use asymmetric molecular cryptography system. With this system, we intend to pioneer the translation of digital public-key cryptography into a chemical-coding one-time-pad-like system.

Trichocyanines: a Red-Hair-Inspired Modular Platform for Dye-Based One-Time-Pad Molecular Cryptography

PubMed Central

Leone, Loredana; Pezzella, Alessandro; Crescenzi, Orlando; Napolitano, Alessandra; Barone, Vincenzo; d’Ischia, Marco

2015-01-01

Current molecular cryptography (MoCryp) systems are almost exclusively based on DNA chemistry and reports of cryptography technologies based on other less complex chemical systems are lacking. We describe herein, as proof of concept, the prototype of the first asymmetric MoCryp system, based on an 8-compound set of a novel bioinspired class of cyanine-type dyes called trichocyanines. These novel acidichromic cyanine-type dyes inspired by red hair pigments were synthesized and characterized with the aid of density functional theory (DFT) calculations. Trichocyanines consist of a modular scaffold easily accessible via an expedient condensation of 3-phenyl- or 3-methyl-2H-1,4-benzothiazines with N-dimethyl- or o-methoxyhydroxy-substituted benzaldehyde or cinnamaldehyde derivatives. The eight representative members synthesized herein can be classified as belonging to two three-state systems tunable through four different control points. This versatile dye platform can generate an expandable palette of colors and appears to be specifically suited to implement an unprecedented single-use asymmetric molecular cryptography system. With this system, we intend to pioneer the translation of digital public-key cryptography into a chemical-coding one-time-pad-like system. PMID:26246999

Asymmetric Zinc Phthalocyanines as Dye-Sensitized Solar Cells

NASA Astrophysics Data System (ADS)

Tunc, Gulenay; Yavuz, Yunus; Gurek, Aysegul; Canimkurbey, Betul; Kosemen, Arif; San, Sait Eren; Ahsen, Vefa

Dye-sensitized solar cells (DSSCs) have received increasing attention due to their high incident to photon efficiency, easy fabrication and low production cost . Tremendous research efforts have been devoted to the development of new and efficient sensitizers suitable for practical use. In TiO2-based DSSCs, efficiencies of up to 11.4% under simulated sunlight have been obtained with rutheniumepolypyridyl complexes. However, the main drawback of ruthenium complexes is the lack of absorption in the red region of the visible light and the high cost. For this reason, dyes with large and stable p-conjugated systems such as porphyrins and phthalocyanines are important classes of potential sensitizers for highly efficient DSSCs. Phthalocyanines (Pcs) have been widely used as sensitizers because of their improved light-harvesting properties in the far red- and near-IR spectral regions and their extraordinary robustness [1]. In this work, a series of asymmetric Zn(II) Pcs bearing a carboxylic acid group and six hexylthia groups either at the peripheral or non-peripheral positions have been designed and synthesized to investigate the influence of the COOH group and the positions of hexylthia groups on the dye-sensitized solar cell (DSSC) performance.

Development of Natural Anthocyanin Dye-Doped Silica Nanoparticles for pH and Borate-Sensing Applications

NASA Astrophysics Data System (ADS)

Ha, Chu T.; Lien, Nghiem T. Ha; Anh, Nguyen D.; Lam, Nguyen L.

2017-12-01

Anthocyanin belongs to a large group of phenolic compounds called flavonoids. It is found primarily in fruits, flowers, roots and other parts of higher plants. Within the black carrot, it has been found that the cyanidin component 1,2 diol was the major anthocyanine. Since the terminal thiols potentially display chemical interactions with borate additives, anthocyanin from the black carrot can act as a sensing material for detecting borate in the environment. As a natural dye, anthocyanin responds to pH change of the medium. Here, we present an application of black carrot dyes for pH sensing and for the detection of borate additives within meats. The dyes were encapsulated within a mesoporous silica (SiO2) matrix in order to prevent the sensing materials from dissolution into the aqueous medium. The encapsulation was done in situ during preparation of silica nanoparticles (size from 100 nm to 500 nm) following an advanced Stöber method. These anthocyanin-encapsulated silica nanoparticles show a clear color change from green in an aqueous solution free of borate to GRAY-red in the presence of borate additive and red (pH 2) to green (pH 10).

Water Quality Criteria for Disperse Red 9

DTIC Science & Technology

1987-07-01

reported in Chin and Borer 1983). The parent compound of Disperse Red 9 is 9,10-anthraquinone; many of the natural and synthetic derivatives of 9,10...and carbonaceous matter (Rubin et al. 1983). 14 The combustion products are a result of thermal decomposition, thermal rearrangement of the parent dye...with individuals becoming more sensitive to subsequent contact (Tatyrok 1965). Parent (1964) reported that Disperse Red 9 is only slightly toxic by

Sensitive spectroscopic detection of large and denatured protein aggregates in solution by use of the fluorescent dye Nile red.

PubMed

Sutter, Marc; Oliveira, Sabrina; Sanders, Niek N; Lucas, Bart; van Hoek, Arie; Hink, Mark A; Visser, Antonie J W G; De Smedt, Stefaan C; Hennink, Wim E; Jiskoot, Wim

2007-03-01

The fluorescent dye Nile red was used as a probe for the sensitive detection of large, denatured aggregates of the model protein beta-galactosidase (E. coli) in solution. Aggregates were formed by irreversible heat denaturation of beta-galactosidase below and above the protein's unfolding temperature of 57.4 degrees C, and the presence of aggregates in heated solutions was confirmed by static light scattering. Interaction of Nile red with beta-galactosidase aggregates led to a shift of the emission maximum (lambda (max)) from 660 to 611 nm, and to an increase of fluorescence intensity. Time-resolved fluorescence and fluorescence correlation spectroscopy (FCS) measurements showed that Nile red detected large aggregates with hydrodynamic radii around 130 nm. By steady-state fluorescence measurements, it was possible to detect 1 nM of denatured and aggregated beta-galactosidase in solution. The comparison with size exclusion chromatography (SEC) showed that native beta-galactosidase and small aggregates thereof had no substantial effect on the fluorescence of Nile red. Large aggregates were not detected by SEC, because they were excluded from the column. The results with beta-galactosidase demonstrate the potential of Nile red for developing complementary analytical methods that overcome the size limitations of SEC, and can detect the formation of large protein aggregates at early stages.

In vivo multispectral photoacoustic and photothermal flow cytometry with multicolor dyes: a potential for real-time assessment of circulation, dye-cell interaction, and blood volume.

PubMed

Proskurnin, Mikhail A; Zhidkova, Tatyana V; Volkov, Dmitry S; Sarimollaoglu, Mustafa; Galanzha, Ekaterina I; Mock, Donald; Nedosekin, Dmitry A; Zharov, Vladimir P

2011-10-01

Recently, photoacoustic (PA) flow cytometry (PAFC) has been developed for in vivo detection of circulating tumor cells and bacteria targeted by nanoparticles. Here, we propose multispectral PAFC with multiple dyes having distinctive absorption spectra as multicolor PA contrast agents. As a first step of our proof-of-concept, we characterized high-speed PAFC capability to monitor the clearance of three dyes (Indocyanine Green [ICG], Methylene Blue [MB], and Trypan Blue [TB]) in an animal model in vivo and in real time. We observed strong dynamic PA signal fluctuations, which can be associated with interactions of dyes with circulating blood cells and plasma proteins. PAFC demonstrated enumeration of circulating red and white blood cells labeled with ICG and MB, respectively, and detection of rare dead cells uptaking TB directly in bloodstream. The possibility for accurate measurements of various dye concentrations including Crystal Violet and Brilliant Green were verified in vitro using complementary to PAFC photothermal (PT) technique and spectrophotometry under batch and flow conditions. We further analyze the potential of integrated PAFC/PT spectroscopy with multiple dyes for rapid and accurate measurements of circulating blood volume without a priori information on hemoglobin content, which is impossible with existing optical techniques. This is important in many medical conditions including surgery and trauma with extensive blood loss, rapid fluid administration, and transfusion of red blood cells. The potential for developing a robust clinical PAFC prototype that is safe for human, and its applications for studying the liver function are further highlighted. Copyright © 2011 International Society for Advancement of Cytometry.

Fluorescent labeling of proteins with amine-specific 1,3,2-(2H)-dioxaborine polymethine dye.

PubMed

Gerasov, Andriy; Shandura, Mykola; Kovtun, Yuriy; Losytskyy, Mykhaylo; Negrutska, Valentyna; Dubey, Igor

2012-01-15

A novel water-soluble amine-reactive dioxaborine trimethine dye was synthesized in a good yield and characterized. The potential of the dye as a specific reagent for protein labeling was demonstrated with bovine serum albumin and lysozyme. Its interaction with proteins was studied by fluorescence spectroscopy and gel electrophoresis. The covalent binding of this almost nonfluorescent dye to proteins results in a 75- to 78-fold increase of its emission intensity accompanied by a red shift of the fluorescence emission maximum by 27 to 45 nm, with fluorescence wavelengths of labeled biomolecules being more than 600 nm. The dye does not require activation for the labeling reaction and can be used in a variety of bioassay applications. Copyright © 2011 Elsevier Inc. All rights reserved.

Plasmachemical degradation of azo dyes by humid air plasma: Yellow Supranol 4 GL, Scarlet Red Nylosan F3 GL and industrial waste.

PubMed

Abdelmalek, F; Gharbi, S; Benstaali, B; Addou, A; Brisset, J L

2004-05-01

A recent non-thermal plasma technique (i.e., a gliding arc discharge which generates reactive species at atmospheric pressure) is tested for pollution abatement of dyes dispersed in synthetic solutions and industrial effluents. Yellow Supranol 4 GL (YS) and Scarlet Red Nylosan F3 GL (SRN) are toxic synthetic dyes widely used in the Algerian textile industry and frequently present in liquid wastes of manufacture plants. Classical removal treatment processes are not efficient enough, so that the presence of dyes in liquid effluents may cause serious environmental problems, in connection with reusing waste waters for irrigation. The degradation processes achieved by the oxidising species formed in the plasma are followed by UV/VIS spectroscopy and by chemical oxygen demand measurements. They are almost complete (i.e., 92.5% for YS and 90% for dilute SRN) and rapidly follow pseudo-first-order laws, with overall estimated rate constants 3 x 10(-4) and 4 x 10(-4)s-1 for YS and SRN, respectively. The degradation rate constant for the industrial mixture (i.e., k = 1.45 x 10(-3)s-1) is a mean value for two consecutive steps (210(-3) and 6 x 10(-5)s-1) measured at the absorption peaks of the major constituent dyes, YS and SRN.

Zinc peroxide nanomaterial as an adsorbent for removal of Congo red dye from waste water.

PubMed

Chawla, Sneha; Uppal, Himani; Yadav, Mohit; Bahadur, Nupur; Singh, Nahar

2017-01-01

In the past decade, various natural byproducts, advanced metal oxide composites and photocatalysts have been reported for removal of dyes from water. Although these materials are useful for select applications, they have some limitations such as use at fixed temperature, ultra violet (UV) light and the need for sophisticated experimental set up. These materials can remove dyes up to a certain extent but require long time. To overcome these limitations, a promising adsorbent zinc peroxide (ZnO 2 ) nanomaterial has been developed for the removal of Congo red (CR) dye from contaminated water. ZnO 2 is highly efficient even in the absence of sunlight to remove CR from contaminated water upto the permissible limits set by the World Health Organization (WHO) and the United States- Environmental Protection Agency (US-EPA). The adsorbent has a specific property to adjust the pH of the test solution within 6.5-7.5 range irrespective of acidic or basic nature of water. The adsorption capacity of the material for CR dye was 208mgg -1 within 10min at 2-10pH range. The proposed material could be useful for the industries involved in water purification. The removal of CR has been confirmed by spectroscopic and microscopic techniques. The adsorption data followed a second order kinetics and Freundlich isotherm. Copyright © 2016 Elsevier Inc. All rights reserved.

Pt@Ag and Pd@Ag core/shell nanoparticles for catalytic degradation of Congo red in aqueous solution.

PubMed

Salem, Mohamed A; Bakr, Eman A; El-Attar, Heba G

2018-01-05

Platinum/silver (Pt@Ag) and palladium/silver (Pd@Ag) core/shell NPs have been synthesized in two steps reaction using the citrate method. The progress of nanoparticle formation was followed by the UV/Vis spectroscopy. Transmission electron microscopy revealed spherical shaped core/shell nanoparticles with average particle diameter 32.17nm for Pt@Ag and 8.8nm for Pd@Ag. The core/shell NPs were further characterized by FT-IR and XRD. Reductive degradation of the Congo red dye was chosen to demonstrate the excellent catalytic activity of these core/shell nanostructures. The nanocatalysts act as electron mediators for the transfer of electrons from the reducing agent (NaBH 4 ) to the dye molecules. Effect of reaction parameters such as nanocatalyst dose, dye and NaBH 4 concentrations on the dye degradation was investigated. A comparison between the catalytic activities of both nanocatalysts was made to realize which of them the best in catalytic performance. Pd@Ag was the higher in catalytic activity over Pt@Ag. Such greater activity is originated from the smaller particle size and larger surface area. Pd@Ag nanocatalyst was catalytically stable through four subsequent reaction runs under the utilized reaction conditions. These findings can thus be considered as possible economical alternative for environmental safety against water pollution by dyes. Copyright © 2017. Published by Elsevier B.V.

Pt@Ag and Pd@Ag core/shell nanoparticles for catalytic degradation of Congo red in aqueous solution

NASA Astrophysics Data System (ADS)

Salem, Mohamed A.; Bakr, Eman A.; El-Attar, Heba G.

2018-01-01

Platinum/silver (Pt@Ag) and palladium/silver (Pd@Ag) core/shell NPs have been synthesized in two steps reaction using the citrate method. The progress of nanoparticle formation was followed by the UV/Vis spectroscopy. Transmission electron microscopy revealed spherical shaped core/shell nanoparticles with average particle diameter 32.17 nm for Pt@Ag and 8.8 nm for Pd@Ag. The core/shell NPs were further characterized by FT-IR and XRD. Reductive degradation of the Congo red dye was chosen to demonstrate the excellent catalytic activity of these core/shell nanostructures. The nanocatalysts act as electron mediators for the transfer of electrons from the reducing agent (NaBH4) to the dye molecules. Effect of reaction parameters such as nanocatalyst dose, dye and NaBH4 concentrations on the dye degradation was investigated. A comparison between the catalytic activities of both nanocatalysts was made to realize which of them the best in catalytic performance. Pd@Ag was the higher in catalytic activity over Pt@Ag. Such greater activity is originated from the smaller particle size and larger surface area. Pd@Ag nanocatalyst was catalytically stable through four subsequent reaction runs under the utilized reaction conditions. These findings can thus be considered as possible economical alternative for environmental safety against water pollution by dyes.

Bichromophoric dyes for wavelength shifting of dye-protein fluoromodules.

PubMed

Pham, Ha H; Szent-Gyorgyi, Christopher; Brotherton, Wendy L; Schmidt, Brigitte F; Zanotti, Kimberly J; Waggoner, Alan S; Armitage, Bruce A

2015-03-28

Dye-protein fluoromodules consist of fluorogenic dyes and single chain antibody fragments that form brightly fluorescent noncovalent complexes. This report describes two new bichromophoric dyes that extend the range of wavelengths of excitation or emission of existing fluoromodules. In one case, a fluorogenic thiazole orange (TO) was attached to an energy acceptor dye, Cy5. Upon binding to a protein that recognizes TO, red emission due to efficient energy transfer from TO to Cy5 replaces the green emission observed for monochromophoric TO bound to the same protein. Separately, TO was attached to a coumarin that serves as an energy donor. The same green emission is observed for coumarin-TO and TO bound to a protein, but efficient energy transfer allows violet excitation of coumarin-TO, versus longer wavelength, blue excitation of monochromophoric TO. Both bichromophores exhibit low nanomolar KD values for their respective proteins, >95% energy transfer efficiency and high fluorescence quantum yields.

Bichromophoric Dyes for Wavelength Shifting of Dye-Protein Fluoromodules

PubMed Central

Pham, Ha H.; Szent-Gyorgyi, Christopher; Brotherton, Wendy L.; Schmidt, Brigitte F.; Zanotti, Kimberly J.; Waggoner, Alan S.

2015-01-01

Dye-protein fluoromodules consist of fluorogenic dyes and single chain antibody fragments that form brightly fluorescent noncovalent complexes. This report describes two new bichromophoric dyes that extend the range of wavelengths of excitation or emission of existing fluoromodules. In one case, a fluorogenic thiazole orange (TO) was attached to an energy acceptor dye, Cy5. Upon binding to a protein that recognizes TO, red emission due to efficient energy transfer from TO to Cy5 replaces the green emission observed for monochromophoric TO bound to the same protein. Separately, TO was attached to a coumarin that serves as an energy donor. The same green emission is observed for coumarin-TO and TO bound to a protein, but efficient energy transfer allows violet excitation of coumarin-TO, versus longer wavelength, blue excitation of monochromophoric TO. Both bichromophores exhibit low nanomolar KD values for their respective proteins, >95% energy transfer efficiency and high fluorescence quantum yields. PMID:25679477

Removal of dissolved textile dyes from wastewater by a compost sorbent

USGS Publications Warehouse

Tsui, L.S.; Roy, W.R.; Cole, M.A.

2003-01-01

The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

Usage of FTIR-ATR as Non-Destructive Analysis of Selected Toxic Dyes

NASA Astrophysics Data System (ADS)

Bartošová, Alica; Blinová, Lenka; Sirotiak, Maroš; Michalíková, Anna

2017-06-01

The degradation of the environment which is due to the discharge of polluting wastewater from industrial sources poses a real problem in several countries. Textile industries use large volumes of water in their operations, discharging thus large volume of wastewater into the environment, most of which is untreated. The wastewater contains a variety of chemicals from various stages of process operations, including desizing, scouring, bleaching and dyeing. The main purpose of this paper is to introduce Infrared Spectrometry with Fourier transformation as a non-destructive method for study, identifation and rapid determination of selected representatives of cationic (Methylene Blue), azo (Congo Red, Eriochrome Black T) and nitroso (Naphthol Green B) dyes. In conjunction with the ATR technique, FTIR offers a reliable detection method of dyes without extraction by other dangerous substances. Spectral interpretation of dye spectra revealed valuable information about the identification and characterization of each group of dyes.

Spectrally resolved visualization of fluorescent dyes permeating into skin

NASA Astrophysics Data System (ADS)

Maeder, Ulf; Bergmann, Thorsten; Beer, Sebastian; Burg, Jan Michael; Schmidts, Thomas; Runkel, Frank; Fiebich, Martin

2012-03-01

We present a spectrally resolved confocal imaging approach to qualitatively asses the overall uptake and the penetration depth of fluorescent dyes into biological tissue. We use a confocal microscope with a spectral resolution of 5 nm to measure porcine skin tissue after performing a Franz-Diffusion experiment with a submicron emulsion enriched with the fluorescent dye Nile Red. The evaluation uses linear unmixing of the dye and the tissue autofluorescence spectra. The results are combined with a manual segmentation of the skin's epidermis and dermis layers to assess the penetration behavior additionally to the overall uptake. The diffusion experiments, performed for 3h and 24h, show a 3-fold increased dye uptake in the epidermis and dermis for the 24h samples. As the method is based on spectral information it does not face the problem of superimposed dye and tissue spectra and therefore is more precise compared to intensity based evaluation methods.

Co-sensitized natural dyes potentially used to enhance light harvesting capability

NASA Astrophysics Data System (ADS)

Amelia, R.; Sawitri, D.; Risanti, D. D.

2015-01-01

We present the photoelectrochemical properties of dye-sensitized solar cells using natural pigments containing anthocyanins, betalains, and caroteins. The dyes were adsorbed by a photoanode that was fabricated from nanocrystalline TiO2 on transparent conductive glass. TiO2 comprises of 100% anatase and 90:10 anatase:rutile fraction. The dyes extracted from mangosteen pericarp, Musa aromatica pericarp, Celosia cristata flower and red beet root were characterized through UV-vis and IPCE. The effectiveness of the dyes was explained through photocurrent as a function of incident light power. It was found that the cocktail and multilayered dyes comprised of anthocyanins and caroteins is beneficial to obtain high photocurrent, whereas betalains is not recommended to be applied on untreated TiO2. Due to the bandgap properties of rutile and anatase, the presence of 10% rutile in TiO2 is favourable to further enhance the electron transport.

Dimeric fluorescent energy transfer dyes comprising asymmetric cyanine azole-indolenine chromophores

DOEpatents

Glazer, Alexander N.; Benson, Scott C.

1998-01-01

Novel fluorescent heterodimeric DNA-staining energy transfer dyes are provided combining asymmetric cyanine azole-indolenine dyes, which provide for strong DNA affinity, large Stokes shifts and emission in the red region of the spectrum. The dyes find particular application in gel electrophoresis and for labels which may be bound to a variety of compositions in a variety of contexts. Kits and individual compounds are provided, where the kits find use for simultaneous detection of a variety of moieties, particularly using a single narrow wavelength irradiation source. The individual compounds are characterized by high donor quenching and high affinity to dsDNA as a result of optimizing the length of the linking group separating the two chromophores.

A viscosity sensitive fluorescent dye for real-time monitoring of mitochondria transport in neurons.

PubMed

Baek, Yeonju; Park, Sang Jun; Zhou, Xin; Kim, Gyungmi; Kim, Hwan Myung; Yoon, Juyoung

2016-12-15

We present here a viscosity sensitive fluorescent dye, namely thiophene dihemicyanine (TDHC), that enables the specific staining of mitochondria. In comparison to the common mitochondria tracker (Mitotracker Deep Red, MTDR), this dye demonstrated its unique ability for robust staining of mitochondria with high photostability and ultrahigh signal-to-noise ratio (SNR). Moreover, TDHC also showed high sensitivity towards mitochondria membrane potential (ΔΨm) and intramitochondria viscosity change. Consequently, this dye was utilized in real-time monitoring of mitochondria transport in primary cortical neurons. Finally, the Two-Photon Microscopy (TPM) imaging ability of TDHC was also demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

Studies on Nano-Engineered TiO2 Photo Catalyst for Effective Degradation of Dye

NASA Astrophysics Data System (ADS)

Sowmya, S. R.; Madhu, G. M.; Hashir, Mohammed

2018-02-01

All Heterogeneous photo catalysis employing efficient photo-catalyst is the advanced dye degradation technology for the purification of textile effluent. The present work focuses on Congo red dye degradation employing synthesized Ag doped TiO2 nanoparticles as photocatalyst which is characterized using SEM, XRD and FTIR. Studies are conducted to study the effect of various parameters such as initial dye concentration, catalyst loading and pH of solution. Ag Doped TiO2 photocatalyst improve the efficacy of TiO2 by reducing high band gap and electron hole recombination of TiO2. The reaction kinetics is analyzed and the process is found to follow pseudo first order kinetics.

Heading toward Gliese 445

NASA Image and Video Library

2013-09-12

The image taken by the Oschin Schmidt Telescope, shows the star AC +79 3888, also known as Gliese 445. NASA Voyager 1 spacecraft, which is on a trajectory out of our solar system, is headed toward an encounter with AC +79 3888 circled in red.

Amputation of congo red dye from waste water using microwave induced grafted Luffa cylindrica cellulosic fiber.

PubMed

Gupta, Vinod Kumar; Pathania, Deepak; Agarwal, Shilpi; Sharma, Shikha

2014-10-13

The present study deals with the surface modification of Luffa cylindrica fiber through graft copolymerization of methyl acrylate/acrylamide (MA/AAm) via microwave radiation without the use of initiator. Various reaction parameters effecting grafting yield were optimized and physico-chemical properties were evaluated. The grafted Luffa cylindrica fiber showed morphological transformations, thermal stability and chemical resistance. The adsorption potential of modified fiber was investigated using adsorption isotherms for hazardous congo red dye removal from aqueous system. The maximum adsorption capacity of dye onto grafted Luffa cylindrica fiber was found to be 17.39 mg/g with best fit for Langmuir adsorption isotherm. The values of thermodynamic parameters such as enthalpy change, ΔH(0) (21.27 kJ/mol), entropy change, ΔS(0) (64.71 J/mol K) and free energy change, ΔG(0) (-139.52 kJ/mol) were also calculated. Adsorption process was found spontaneous and endothermic in nature. Copyright © 2014 Elsevier Ltd. All rights reserved.

An organic dye-polymer (phenol red-poly (vinyl alcohol)) composite architecture towards tunable -optical and -saturable absorption characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreedhar, Sreeja, E-mail: sreejasreedhar83@gmail.com; Muneera, C. I., E-mail: drcimuneera@hotmail.com; Illyaskutty, Navas

2016-05-21

Herein, we demonstrate that blending an organic dye (guest/filler), with a vinyl polymer (host template), is an inexpensive and simple approach for the fabrication of multifunctional photonic materials which could display an enhancement in the desirable properties of the constituent materials and, at the same time provide novel synergistic properties for the guest-host system. A new guest-host nanocomposite system comprising Phenol Red dye and poly (vinyl alcohol) as guest and host template, respectively, which exhibits tunable optical characteristics and saturable absorption behavior, is introduced. The dependence of local electronic environment provided by the polymer template and the interactions of themore » polymer molecules with the encapsulated guest molecules on the observed optical/nonlinear absorption behavior is discussed. An understanding of the tunability of the optical/ photophysical processes, with respect to the filler content, as discussed herein could help in the design of improved optical materials for several photonic device applications like organic light emitting diodes and saturable absorbers.« less

Extraction methods and food uses of a natural red colorant from dye sorghum.

PubMed

Akogou, Folachodé Ug; Kayodé, Ap Polycarpe; den Besten, Heidy Mw; Linnemann, Anita R

2018-01-01

The interest in stable natural colorants for food applications continues to grow. A red pigment extracted from the leaf sheaths of a sorghum variety (Sorghum bicolor) with a high content of apigeninidin is widely used as a biocolorant in processed foods in West Africa. This study compared the colour and anthocyanin composition from traditional extraction methods to determine options for improvement and use of the red biocolorant from dye sorghum in the food sector. Sorghum biocolorant was commonly applied in fermented and heated foods. Traditional extraction methods predominantly differed in two aspects, namely the use of an alkaline rock salt (locally known as kanwu) and the temperature of the extraction water. Cool extraction using the alkaline ingredient was more efficient than hot alkaline and hot aqueous extractions in extracting anthocyanins. The apigeninidin content was three times higher in the cool and hot alkaline extracts than in the aqueous extract. Cool and hot alkaline extractions at pH 8-9 were the most efficient methods for extracting apigeninidin from dye sorghum leaf sheaths. Broader use of the sorghum biocolorant in foods requires further research on its effects on nutrient bioavailability and antioxidant activity. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Characterization of form variants of Xenorhabdus luminescens.

PubMed Central

Gerritsen, L J; de Raay, G; Smits, P H

1992-01-01

From Xenorhabdus luminescens XE-87.3 four variants were isolated. One, which produced a red pigment and antibiotics, was luminescent, and could take up dye from culture media, was considered the primary form (XE-red). A pink-pigmented variant (XE-pink) differed from the primary form only in pigmentation and uptake of dye. Of the two other variants, one produced a yellow pigment and fewer antibiotics (XE-yellow), while the other did not produce a pigment or antibiotics (XE-white). Both were less luminescent, did not take up dye, and had small cell and colony sizes. These two variants were very unstable and shifted to the primary form after 3 to 5 days. It was not possible to separate the primary form and the white variant completely; subcultures of one colony always contained a few colonies of the other variant. The white variant was also found in several other X. luminescens strains. DNA fingerprints showed that all four variants are genetically identical and are therefore derivatives of the same parent. Protein patterns revealed a few differences among the four variants. None of the variants could be considered the secondary form. The pathogenicity of the variants decreased in the following order: XE-red, XE-pink, XE-yellow, and XE-white. The mechanism and function of this variability are discussed. Images PMID:1622273

Theoretical studies on effective metal-to-ligand charge transfer characteristics of novel ruthenium dyes for dye sensitized solar cells.

PubMed

Wang, Huei-Tang; Taufany, Fadlilatul; Nachimuthu, Santhanamoorthi; Jiang, Jyh-Chiang

2014-05-01

The development of ruthenium dye-sensitizers with highly effective metal-to-ligand charge transfer (MLCT) characteristics and narrowed transition energy gaps are essential for the new generation of dye-sensitized solar cells. Here, we designed a novel anchoring ligand by inserting the cyanovinyl-branches inside the anchoring ligands of selected highly efficient dye-sensitizers and studied their intrinsic optical properties using theoretical methods. Our calculated results show that the designed ruthenium dyes provide good performances as sensitizers compared to the selected efficient dyes, because of their red-shift in the UV-visible absorption spectra with an increase in the absorption intensity, smaller energy gaps and thereby enhancing MLCT transitions. We found that, the designed anchoring ligand acts as an efficient "electron-acceptor" which boosts electron-transfer from a -NCS ligand to this ligand via a Ru-bridge, thus providing a way to lower the transition energy gap and enhance the MLCT transitions.

21 CFR 74.1306 - D&C Red No. 6.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false D&C Red No. 6. 74.1306 Section 74.1306 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid. The resulting dye precipitates as the disodium salt...

21 CFR 74.1306 - D&C Red No. 6.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false D&C Red No. 6. 74.1306 Section 74.1306 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid. The resulting dye precipitates as the disodium salt...

21 CFR 74.1306 - D&C Red No. 6.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false D&C Red No. 6. 74.1306 Section 74.1306 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid. The resulting dye precipitates as the disodium salt...

Effect of acidity on the energy level of curcumin dye extracted from Curcuma longa L

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agustia, Yuda Virgantara, E-mail: yuda.mechanical.engineer@student.uns.ac.id; Suyitno,, E-mail: suyitno@uns.ac.id; Sutanto, Bayu, E-mail: bayu.sutanto@student.uns.ac.id

2016-03-29

The purpose of this research is to investigate the effect of acidity on the energy level of curcumin dye. The natural dye, curcumin, was synthesized from Curcuma longa L. using a simple extraction technique. The purification of curcumin dye was conducted in a column of chromatography and its characteristics were studied. Next, the purified curcumin dye was added by benzoic acids until various acidities of 3.0, 3.5, 4.0, 4.5, and 5.0. The absorbance spectra and the functionality groups found in the dyes were detected by ultraviolet-visible spectroscopy and Fourier-transform infrared spectroscopy, respectively. Meanwhile, the energy level of the dyes, E{submore » HOMO} and E{sub LUMO} was measured by cyclic voltammetry. The best energy level of curcumin dye was achieved at pH 3.5 where E{sub red} = −0.37V, E{sub LUMO} = −4.28 eV, E{sub ox} = 1.15V, E{sub HOMO} = −5.83 eV, and E{sub band} {sub gap} = 1.55 eV. Therefore, the purified curcumin dye added by benzoic acid was promising for sensitizing the dye-sensitized solar cells.« less

Chemical Characterization and Toxicologic Evaluation of Airborne Mixtures. Tumorigenicity Studies of Diesel Fuel-2, Red Smoke Dye and Violet Smoke Dyes in the SENCAR Mouse Skin Tumorigenesis Bioassay System

DTIC Science & Technology

1985-09-01

11, 4. TITLE (and Subtitle) Chemical Characterization and Toxi - S. TYPE OF REPORT & PERIOD COVERED cologic Evaluation of Airborne Mixtures / Technical...REFERENCES (Cont’d) Nesnow, S., L. L. Triplett, and T. J. Slaga. 1981. Tumorigenesis of diesel exhaust, gasoline exhaust, and related emission

Comparative study of toxicity of azo dye Procion Red MX-5B following biosorption and biodegradation treatments with the fungi Aspergillus niger and Aspergillus terreus.

PubMed

Almeida, E J R; Corso, C R

2014-10-01

Azo dyes are an important class of environmental contaminants and are characterized by the presence of one or more azo bonds (-N=N-) in their molecular structure. Effluents containing these compounds resist many types of treatments due to their molecular complexity. Therefore, alternative treatments, such as biosorption and biodegradation, have been widely studied to solve the problems caused by these substances, such as their harmful effects on the environment and organisms. The aim of the present study was to evaluate biosorption and biodegradation of the azo dye Procion Red MX-5B in solutions with the filamentous fungi Aspergillus niger and Aspergillus terreus. Decolorization tests were performed, followed by acute toxicity tests using Lactuca sativa seeds and Artemia salina larvae. Thirty percent dye removal of the solutions was achieved after 3 h of biosorption. UV-Vis spectroscopy revealed that removal of the dye molecules occurred without major molecular changes. The acute toxicity tests confirmed lack of molecular degradation following biosorption with A. niger, as toxicity to L. sativa seed reduced from 5% to 0%. For A. salina larvae, the solutions were nontoxic before and after treatment. In the biodegradation study with the fungus A. terreus, UV-Vis and FTIR spectroscopy revealed molecular degradation and the formation of secondary metabolites, such as primary and secondary amines. The biodegradation of the dye molecules was evaluated after 24, 240 and 336 h of treatment. The fungal biomass demonstrated considerable affinity for Procion Red MX-5B, achieving approximately 100% decolorization of the solutions by the end of treatment. However, the solutions resulting from this treatment exhibited a significant increase in toxicity, inhibiting the growth of L. sativa seeds by 43% and leading to a 100% mortality rate among the A. salina larvae. Based on the present findings, biodegradation was effective in the decolorization of the samples, but generated toxic metabolites, while biosorption was effective in both decolorization and reducing the toxicity of the solutions. Published by Elsevier Ltd.

Ozonation of exhausted dark shade reactive dye bath for reuse.

PubMed

Sundrarajan, M; Vishnu, G; Joseph, Kurian

2006-10-01

Exhausted reactive dye bath of dark shades were collected from cotton knit wear dyeing units in Tirupur. Ozonation was conducted in a column reactor system fed with ozone at the rate of 0.16 g/min to assess its efficiency in reducing the color, chemical oxygen demand and total organic carbon. The potential of the decolorized dye bath for its repeated reuse was also analyzed. The results from the reusability studies indicate that the dyeing quality was not affected by the reuse of decolorized dye bath for two successive cycles. Complete decolorization of the effluent was achieved in 60 minutes contact time at an ozone consumption of 183 mg/L for Red, 175 for Navy Blue and 192 for Green shades respectively. The corresponding COD removal was 60%, 54% and 63% for the three shades while TOC removal efficiency was 59%, 55% and 62% respectively. It is concluded that ozonation is efficient in decolorization of exhausted dye bath effluents containing conventional reactive dyes. However, the corresponding removal of COD from the textile effluent was not significant.

Oxidation of Levafix CA reactive azo-dyes in industrial wastewater of textile dyeing by electro-generated Fenton's reagent.

PubMed

El-Desoky, Hanaa S; Ghoneim, Mohamed M; El-Sheikh, Ragaa; Zidan, Naglaa M

2010-03-15

The indirect electrochemical removal of pollutants from effluents has become an attractive method in recent years. Removal (decolorization and mineralization) of Levafix Blue CA and Levafix Red CA reactive azo-dyes from aqueous media by electro-generated Fenton's reagent (Fe(2+)/H(2)O(2)) using a reticulated vitreous carbon cathode and a platinum gauze anode was optimized. Progress of oxidation (decolorization and mineralization) of the investigated azo-dyes with time of electro-Fenton's reaction was monitored by UV-visible absorbance measurements, Chemical oxygen demand (COD) removal and HPLC analysis. The results indicated that the electro-Fenton's oxidation system is efficient for treatment of such types of reactive dyes. Oxidation of each of the investigated azo-dyes by electro-generated Fenton's reagent up to complete decolorization and approximately 90-95% mineralization was achieved. Moreover, the optimized electro-Fenton's oxidation was successfully applied for complete decolorization and approximately 85-90% mineralization of both azo-dyes in real industrial wastewater samples collected from textile dyeing house at El-Mahalla El-Kobra, Egypt. (c) 2009 Elsevier B.V. All rights reserved.

Removal of vertigo blue dyes from Batik textile wastewater by adsorption onto activated carbon and coal bottom ash

NASA Astrophysics Data System (ADS)

Kusmiyati, L., Puspita Adi; Deni, V.; Robi Indra, S.; Islamica, Dlia; Fuadi, M.

2016-04-01

Removal of vertigo blue dye from batik textile wastewater was studied by adsorptionprocess onto activated carbon (AC) and coal bottom ash (CBA).The influence of experimental conditions (pH solution, dye concentration, and contact time) were studied on the both adsorbents. At equilibrium conditions, the data were fitted to Langmuir and Freundlich adsorption models. The maximum adsorption capacity calculated from the Langmuir model for carbon active was 6.29mg/g at pH that found to be considerably higher than that obtained for coal bottom ash 3.72mg/g pH 9. From Freundlich model, the maximum adsorption capacity is less for coal bottom ash (pH 9) than that for carbon active (pH4).

Novel benzanthrone probes for membrane and protein studies

NASA Astrophysics Data System (ADS)

Ryzhova, Olga; Vus, Kateryna; Trusova, Valeriya; Kirilova, Elena; Kirilov, Georgiy; Gorbenko, Galyna; Kinnunen, Paavo

2016-09-01

The applicability of a series of novel benzanthrone dyes to monitoring the changes in physicochemical properties of lipid bilayer and to differentiating between the native and aggregated protein states has been evaluated. Based on the quantitative parameters of the dye-membrane and dye-protein binding derived from the fluorimetric titration data, the most prospective membrane probes and amyloid tracers have been selected from the group of examined compounds. Analysis of the red edge excitation shifts of the membrane- and amyloid-bound dyes provided information on the properties of benzanthrone binding sites within the lipid and protein matrixes. To understand how amyloid specificity of benzanthrones correlates with their structure, quantitative structure activity relationship (QSAR) analysis was performed involving a range of quantum chemical molecular descriptors. A statistically significant model was obtained for predicting the sensitivity of novel benzanthrone dyes to amyloid fibrils.

A Dipolar Anthracene Dye: Synthesis, Optical Properties and Two-photon Tissue Imaging.

PubMed

Moon, Hyunsoo; Jun, Yong Woong; Kim, Dokyoung; Ryu, Hye Gun; Wang, Taejun; Kim, Ki Hean; Huh, Youngbuhm; Jung, Junyang; Ahn, Kyo Han

2016-09-20

Two-photon microscopy is a powerful tool for studying biological systems. In search of novel two-photon absorbing dyes for bioimaging, we synthesized a new anthracene-based dipolar dye (anthradan) and evaluated its two-photon absorbing and imaging properties. The new anthradan, 9,10-bis(o-dimethoxy-phenyl)-anthradan, absorbs and emits at longer wavelengths than acedan, a well-known two-photon absorbing dye. It is also stable under two-photon excitation conditions and biocompatible, and thus used for two-photon imaging of mouse organ tissues to show bright, near-red fluorescence along with negligible autofluorescence. Such an anthradan thus holds promise as a new class of two-photon absorbing dyes for the development of fluorescent probes and tags for biological systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

AC electroosmotic micromixer for chemical processing in a microchannel.

PubMed

Sasaki, Naoki; Kitamori, Takehiko; Kim, Haeng-Boo

2006-04-01

A rapid micromixer of fluids in a microchannel is presented. The mixer uses AC electroosmotic flow, which is induced by applying an AC voltage to a pair of coplanar meandering electrodes configured in parallel to the channel. To demonstrate performance of the mixer, dilution experiments were conducted using a dye solution in a channel of 120 microm width. Rapid mixing was observed for flow velocity up to 12 mm s(-1). The mixing time was 0.18 s, which was 20-fold faster than that of diffusional mixing without an additional mixing mechanism. Compared with the performance of reported micromixers, the present mixer worked with a shorter mixing length, particularly at low Peclet numbers (Pe < 2 x 10(3)).

Adsorption orientation effects of porphyrin dyes on the performance of DSSC: Comparison of benzoic acid and tropolone anchoring groups binding onto the TiO2 anatase (101) surface

NASA Astrophysics Data System (ADS)

Zhu, Han-Cheng; Zhang, Ji; Wang, Ying-Lin

2018-03-01

A new porphyrin dye with tropolone anchoring group showing superior stability but lower efficiency versus the promising dye YD2-o-C8 with benzoic acid anchoring group was theoretically investigated for the first time. A series of important parameters related to the efficiency of DSSC were calculated to explore the nature of the experimentally observed lower efficiency and superior stability of tropolone-based solar cells. We found these two dyes with different anchoring groups show comparable electron injection and dye regeneration process. Interestingly, the red-shifted absorption spectrum, relatively weaker ability of releasing protons, and the larger conduction band energy shift of tropolone-based dyes all demonstrated it should show better performance than the benzoic acid dyes, which contradicts with the experimental results. However, through investigating the interaction between the porphyrin dye and the semiconductor by analyzing the electron localization function of the porphyrin dye and preforming energy decomposition analysis, we found that the direction of lone-pair electrons of carbonyl oxygen in the tropolone-based dye makes the dye prefer to adsorb on the surface in an inclined way, in contrary to the benzoic acid-based dye that favored a vertical adsorption. The inclined adsorption could significantly accelerate the charge recombination process between the injected electrons and the oxidized dye, leading to a decreased efficiency of DSSC.

Synthesis and anion recognition studies of novel bis (4-hydroxycoumarin) methane azo dyes

NASA Astrophysics Data System (ADS)

Panitsiri, Amorn; Tongkhan, Sukanya; Radchatawedchakoon, Widchaya; Sakee, Uthai

2016-03-01

Four new bis (4-hydroxycoumarin) methane azo dyes were synthesized by the condensation of 4-hydroxycoumarin with four different azo salicylaldehydes and their structures were characterized by FT-IR, 1H NMR, 13C NMR, HRMS. Anion binding ability in dimethyl sulfoxide (DMSO) solutions with tetrabutylammonium (TBA) salts (F-, Cl-, Br-, I-, AcO- and H2PO4-) was investigated by the naked eye, as well as UV-visible spectroscopy. The sensor shows selective recognition towards fluoride and acetate. The binding affinity of the sensors with fluoride and acetate was calculated using UV-visible spectroscopic technique.

Co-extruded mechanically tunable multilayer elastomer laser

NASA Astrophysics Data System (ADS)

Crescimanno, Michael; Mao, Guilin; Andrews, James; Singer, Kenneth; Baer, Eric; Hiltner, Anne; Song, Hyunmin; Shakya, Bijayandra

2011-04-01

We have fabricated and studied mechanically tunable elastomer dye lasers constructed in large area sheets by a single-step layer-multiplying co-extrusion process. The laser films consist of a central dye-doped (Rhodamine-6G) elastomer layer between two 128-layer distributed Bragg reflector (DBR) films comprised of alternating elastomer layers with different refractive indices. The central gain layer is formed by folding the coextruded DBR film to enclose a dye-doped skin layer. By mechanically stretching the elastomer laser film from 0% to 19%, a tunable miniature laser source was obtained with ˜50 nm continuous tunability from red to green.

Noncovalent labeling of biomolecules with red and near- infrared dyes.

PubMed

Patonay, Gabor; Salon, Jozef; Sowell, John; Strekowski, Lucjan

2004-02-28

Biopolymers such as proteins and nucleic acids can be labeled with a fluorescent marker to allow for their detection. Covalent labeling is achieved by the reaction of an appropriately functionalized dye marker with a reactive group on a biomolecule. The recent trend, however, is the use of noncovalent labeling that results from strong hydrophobic and/or ionic interactions between the marker and biomolecule of interest. The main advantage of noncovalent labeling is that it affects the functional activity of the biomolecule to a lesser extent. The applications of luminescent cyanine and squarylium dyes are reviewed.

Utilization of biogenic tea waste silver nanoparticles for the reduction of organic dyes

NASA Astrophysics Data System (ADS)

Kaur, H.; Jaryal, N.

2018-05-01

Eco-friendly synthesis of nanoparticles is the need of the society today. Present study has been undertaken to investigate the greener approach for the preparation of medicinally and chemically important nanoparticles. Tea waste has been taken to synthesis silver nanoparticles. The nanoparticles are characterized by x-ray Diffraction, and Transmission Emission Microscopy studies. The particle size varied from 2 to 34 nm. These silver nanoparticles were evaluated for their reducing activity against four organic dyes viz crystal violet, methylene blue, Congo red and brilliant green. The particles exhibited good catalytic activity against crystal violet, methylene blue and brilliant green but no activity was visible for Congo red. Furthermore, AgNPs shows very promising and prominent antioxidant activity.

Curcuma longa extract as a histological dye for collagen fibres and red blood cells

PubMed Central

Avwioro, O G; Onwuka, S K; Moody, J O; Agbedahunsi, J M; Oduola, T; Ekpo, O E; Oladele, A A

2007-01-01

Crude ethanolic extract and column chromatographic fractions of the Allepey cultivar of Curcuma longa Roxb, commonly called turmeric (tumeric) in commerce, were used as a stain for tissue sections. Staining was carried out under basic, acidic and neutral media conditions. Inorganic and organic dissolution solvents were used. The stain was used as a counterstain after alum and iron haematoxylins. C. longa stained collagen fibres, cytoplasm, red blood cells and muscle cells yellow. It also stained in a fashion similar to eosin, except for its intense yellow colour. Preliminary phytochemical evaluation of the active column fraction revealed that it contained flavonoids, free anthraquinone and deoxy sugar. A cheap, natural dye can thus be obtained from C. longa. PMID:17451535

Adsorption and Corrosion Inhibition Studies of Some Selected Dyes as Corrosion Inhibitors for Mild Steel in Acidic Medium: Gravimetric, Electrochemical, Quantum Chemical Studies and Synergistic Effect with Iodide Ions.

PubMed

Peme, Thabo; Olasunkanmi, Lukman O; Bahadur, Indra; Adekunle, Abolanle S; Kabanda, Mwadham M; Ebenso, Eno E

2015-09-02

The corrosion inhibition properties of some organic dyes, namely Sunset Yellow (SS), Amaranth (AM), Allura Red (AR), Tartrazine (TZ) and Fast Green (FG), for mild steel corrosion in 0.5 M HCl solution, were investigated using gravimetric, potentiodynamic polarization techniques and quantum chemical calculations. The results showed that the studied dyes are good corrosion inhibitors with enhanced inhibition efficiencies. The inhibition efficiency of all the studied dyes increases with increase in concentration, and decreases with increase in temperature. The results showed that the inhibition efficiency of the dyes increases in the presence of KI due to synergistic interactions of the dye molecules with iodide (I(-)) ions. Potentiodynamic polarization results revealed that the studied dyes are mixed-type inhibitors both in the absence and presence of KI. The adsorption of the studied dyes on mild steel surface, with and without KI, obeys the Langmuir adsorption isotherm and involves physical adsorption mechanism. Quantum chemical calculations revealed that the most likely sites in the dye molecules for interactions with mild steel are the S, O, and N heteroatoms.

Batchwise dyeing of bamboo cellulose fabric with reactive dye using ultrasonic energy.

PubMed

Larik, Safdar Ali; Khatri, Awais; Ali, Shamshad; Kim, Seong Hun

2015-05-01

Bamboo is a regenerated cellulose fiber usually dyed with reactive dyes. This paper presents results of the batchwise dyeing of bamboo fabric with reactive dyes by ultrasonic (US) and conventional (CN) dyeing methods. The study was focused at comparing the two methods for dyeing results, chemicals, temperature and time, and effluent quality. Two widely used dyes, CI Reactive Black 5 (bis-sulphatoethylsulphone) and CI Reactive Red 147 (difluorochloropyrimidine) were used in the study. The US dyeing method produced around 5-6% higher color yield (K/S) in comparison to the CN dyeing method. A significant savings in terms of fixation temperature (10°C) and time (15 min), and amounts of salt (10 g/L) and alkali (0.5-1% on mass of fiber) was realized. Moreover, the dyeing effluent showed considerable reductions in the total dissolved solids content (minimum around 29%) and in the chemical oxygen demand (minimum around 13%) for the US dyebath in comparison to the CN dyebath. The analysis of colorfastness tests demonstrated similar results by US and CN dyeing methods. A microscopic examination on the field emission scanning electron microscope revealed that the US energy did not alter the surface morphology of the bamboo fibers. It was concluded that the US dyeing of bamboo fabric produces better dyeing results and is a more economical and environmentally sustainable method as compared to CN dyeing method. Copyright © 2014 Elsevier B.V. All rights reserved.

Antiedematogenic effects of the polar fractions of Persea cordata Mez. (Lauraceae) on microvascular extravasation in rat skin.

PubMed

Schlemper, Valfredo; Schlemper, Susana Regina de Mello; Zampirolo, Júlio Araújo

2013-10-28

Persea cordata Mez. (Lauraceae) is a medicinal plant used in veterinary ethnopharmacology, which is a popular medicine used as an anti-inflammatory and healing agent, mainly on animal skin diseases, characterized by cutaneous open wounds, in South Brazil. The purpose of this study was to investigate a possible antiedematogenic effect of ethyl acetate (EtAc) and butanol (BuOH) polar fractions of Persea cordata on Evans blue dye leakage induced by pro-inflammatory agents in rat skin. Male Wistar rats (180-200 g, n=5-6) were pretreated with a single intraperitoneal administration of EtAc or BuOH (1 to 600 mg kg(-1)) fractions followed by intravenous Evans blue dye injection (1%, 30 mg kg(-1), i.v.), 60 min before the injection of phlogistic agents. Animals received intradermal injections (0.05 ml) of carrageenan (CAR, 300 µg/site), 48/80 compound (C4880, 10 µg/site), histamine (HIS, 0.3 µg/site), serotonin (5-HT, 0.01 µg/site), dextran (DEX, 200 µg/site), bradykinin (BK, 0.003 µg/site), capsaicin (CPS, 400 µg/site), substance P (SP, 0.003 µg/site) or prostaglandin E2 (PGE2 10 nmol/site) and they were submitted to euthanasia after 60 min. Skin samples were obtained in the extravasation sites of Evans blue dye. Skin fragments were soaked in formamide at 37°C (during 24h) for Evans blue extraction. The amount of dye leakage in the tissue fragment was determined by a spectrophotometer (620 nm). In a very similar manner in terms of potency and efficacy, systemic administration of EtAc and BuOH fractions caused dose-dependent inhibition of vascular Evans blue dye leakage induced by phlogistic agents in the rat skin. The results obtained (ID50 values in mgkg(-1) and maximal inhibition in %) with EtAc fraction, as follows were: CAR (34.42 and 63.0), 4880 (8.52 and 59.1), HIS (21.22 and 66.8), 5-HT (32.99 and 73.4), DEX (41.74 and 67.0), BK (34.03 and 68.0), CPS (100.7 and 77), SP (2.1 and 78.9) and PGE2 (133 and 71.0). BuOH fraction significantly inhibited CAR (25.9 and 70)-, 4880 (36.8 and 66)-, HIS (17.6 and 77)-, 5-HT (32.8 and 56)-, DEX (89.6 and 75)-, BK (28.0 and 66)-, CPS (136.37 and 71)-, SP (5.6 and 78)- and PGE2 (109.64 and 56)-induced VE, respectively. Systemic administration of Persea cordata polar fractions exerts a non-specific inhibitory effect on microvascular leakage induced by pro-inflammatory agents in rat skin, probably to interfering with different biological systems involved in the development of the inflammatory process, reinforcing the popular use of Persea cordata as an anti-inflammatory and healing agent for skin. © 2013 Elsevier Ireland Ltd. All rights reserved.

Dye-binding assays for evaluation of the effects of small molecule inhibitors on amyloid (aβ) self-assembly.

PubMed

Jameson, Laramie P; Smith, Nicholas W; Dzyuba, Sergei V

2012-11-21

Dye-binding assays, such as those utilizing Congo red and thioflavin T, are among the most widely used tools to probe the aggregation of amyloidogenic biomolecules and for the evaluation of small molecule inhibitors of amyloid aggregation and fibrillization. A number of recent reports have indicated that these dye-binding assays could be prone to false positive effects when assessing inhibitors' potential toward Aβ peptides, species involved in Alzheimer's disease. Specifically, this review focuses on the application of thioflavin T for determining the efficiency of small molecule inhibitors of Aβ aggregation and addresses potential reasons that might be associated with the false positive effects in an effort to increase reliability of dye-binding assays.

Dye-Binding Assays for Evaluation of the Effects of Small Molecule Inhibitors on Amyloid (Aβ) Self-Assembly

PubMed Central

2012-01-01

Dye-binding assays, such as those utilizing Congo red and thioflavin T, are among the most widely used tools to probe the aggregation of amyloidogenic biomolecules and for the evaluation of small molecule inhibitors of amyloid aggregation and fibrillization. A number of recent reports have indicated that these dye-binding assays could be prone to false positive effects when assessing inhibitors’ potential toward Aβ peptides, species involved in Alzheimer’s disease. Specifically, this review focuses on the application of thioflavin T for determining the efficiency of small molecule inhibitors of Aβ aggregation and addresses potential reasons that might be associated with the false positive effects in an effort to increase reliability of dye-binding assays. PMID:23173064

Red Blood Cell Volume, Plasma Volume and Total Blood Volume in Healthy Elderly Men and Women Aged 64 to 100

DTIC Science & Technology

1992-05-06

Robert Valeri, Linda E. Pivacek, Hiliary Siebens, and Mark D. Altschule ». PERFORMING ORGANIZATION NAME AND AOORESS Naval Blood Research Laboratory...Gibson JG, Peacock WC, Seligman AM, Sack T: Circulating red cell volume measured simultaneously by the radioactive iron and dye methods. J Clin

21 CFR 74.1307 - D&C Red No. 7.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false D&C Red No. 7. 74.1307 Section 74.1307 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid and the resulting dye converted to the calcium salt...

21 CFR 74.1307 - D&C Red No. 7.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false D&C Red No. 7. 74.1307 Section 74.1307 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid and the resulting dye converted to the calcium salt...

21 CFR 74.1307 - D&C Red No. 7.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false D&C Red No. 7. 74.1307 Section 74.1307 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... medium with 3-hydroxy-2-naphthalenecarboxylic acid and the resulting dye converted to the calcium salt...

Correlated accumulation of anthocyanins and rosmarinic acid in mechanically stressed red cell suspensions of basil (Ocimum basilicum).

PubMed

Strazzer, Pamela; Guzzo, Flavia; Levi, Marisa

2011-02-15

A red basil cell line (T2b) rich in rosmarinic acid (RA) was selected for the stable production of anthocyanins (ACs) in the dark. Cell suspension cultures were subjected to mechanical stress through increased agitation (switch from 90 to 150 rpm) to determine the relationship between AC and RA accumulation. Cell extracts were analyzed by HPLC and LC-MS, and the resulting data were processed with multivariate statistical analysis. MS and MS/MS spectra facilitated the putative annotation of several complex cyanidin-based ACs, which were esterified with coumaric acid and, in some cases, also with malonic acid. It was also possible to identify various RA-related molecules, some caffeic and coumaric acid derivatives and some flavanones. Mechanical stress increased the total AC and RA contents, but reduced biomass accumulation. Many metabolites were induced by mechanical stress, including RA and some of its derivatives, most ACs, hydroxycinnamic acids and flavonoids, whereas the abundance of some RA dimers was reduced. Although AC and RA share a common early biosynthetic pathway (from phenylalanine to 4-coumaroyl-CoA) and could have similar or overlapping functions providing antioxidant activity against stress-generated reactive oxygen species, there appeared to be no competition between their individual pathways. Copyright © 2010 Elsevier GmbH. All rights reserved.

Tumors induce coordinate growth of artery, vein, and lymphatic vessel triads.

PubMed

Ruddell, Alanna; Croft, Alexandra; Kelly-Spratt, Karen; Furuya, Momoko; Kemp, Christopher J

2014-05-21

Tumors drive blood vessel growth to obtain oxygen and nutrients to support tumor expansion, and they also can induce lymphatic vessel growth to facilitate fluid drainage and metastasis. These processes have generally been studied separately, so that it is not known how peritumoral blood and lymphatic vessels grow relative to each other. The murine B16-F10 melanoma and chemically-induced squamous cell carcinoma models were employed to analyze large red-colored vessels growing between flank tumors and draining lymph nodes. Immunostaining and microscopy in combination with dye injection studies were used to characterize these vessels. Each peritumoral red-colored vessel was found to consist of a triad of collecting lymphatic vessel, vein, and artery, that were all enlarged. Peritumoral veins and arteries were both functional, as detected by intravenous dye injection. The enlarged lymphatic vessels were functional in most mice by subcutaneous dye injection assay, however tumor growth sometimes blocked lymph drainage to regional lymph nodes. Large red-colored vessels also grew between benign papillomas or invasive squamous cell carcinomas and regional lymph nodes in chemical carcinogen-treated mice. Immunostaining of the red-colored vessels again identified the clustered growth of enlarged collecting lymphatics, veins, and arteries in the vicinity of these spontaneously arising tumors. Implanted and spontaneously arising tumors induce coordinate growth of blood and lymphatic vessel triads. Many of these vessel triads are enlarged over several cm distance between the tumor and regional lymph nodes. Lymphatic drainage was sometimes blocked in mice before lymph node metastasis was detected, suggesting that an unknown mechanism alters lymph drainage patterns before tumors reach draining lymph nodes.

Influence of azo dye concentration on activated sludge bacterial community in the presence of functionalized polyurethane foam.

PubMed

Lu, Hong; Wang, Jing; Lu, Shuilong; Wang, Ying; Liu, Guangfei; Zhou, Jiti; Quan, Zhexue

2015-03-01

Immobilized quinones exhibit good catalytic performance in the biodecolorization of azo dyes. However, in practical activated sludge systems, little is known about the effect of azo dye concentration on microbial communities in the presence of immobilized quinones. 454 Pyrosequencing was used to investigate structural changes and to determine the key microorganisms involved in Reactive Red X-3B decolorization in the presence of anthraquinone-2-sulfonate immobilized on polyurethane foam (AQS-PUF). Our results show that the AQS-PUF-supplemented system exhibited better stability and decolorization performance during a 30-day run than polyurethane-foam-only (PUF-supplemented) and control systems. Analysis of pyrosequencing data showed that the AQS-PUF-supplemented system had the highest bacterial diversity, followed by the control and PUF-supplemented systems during decolorization. Reactive Red X-3B and AQS-PUF significantly influenced bacterial communities at the class level: Erysipelotrichia and the most dominant Deltaproteobacteria showed significant positive correlations with Reactive Red X-3B, while unclassified Firmicutes were found to be significantly correlated with AQS-PUF. At the genus level, Desulfomicrobium, which represents 8-44 % of the total population, displayed a significant positive correlation with Reactive Red X-3B. Some bacteria, including Desulfovibrio, Shewanella, and Clostridium with relative abundances of less than 6 %, were positively correlated with AQS-PUF. These findings provide a novel insight into the changes that occur in the bacterial community during immobilized AQS-mediated decolorization. Less abundant quinone-reducing bacteria play important roles in accelerating the effect of AQS-PUF on biodecolorization.

The oxygen-rich pentaerythritol modified multi-walled carbon nanotube as an efficient adsorbent for aqueous removal of alizarin yellow R and alizarin red S

NASA Astrophysics Data System (ADS)

Yang, Jia-Ying; Jiang, Xin-Yu; Jiao, Fei-Peng; Yu, Jin-Gang

2018-04-01

A contrastive work on the removal of two organic dyes, alizarin yellow R (AYR) and alizarin red S (ARS), was carried out by utilizing pentaerythritol modified multi-walled carbon nanotubes (ox-MWCNT-PER) as a highly efficient adsorbent. Various characterization methods such as scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, the Brunauer-Emmett-Teller (BET) analysis and X-ray photoelectron spectroscopy (XPS), were applied for revealing the physical and chemical properties of the as-prepared material. In addition, the adsorption kinetics, isotherms and thermodynamic parameters were also discussed. The results showed that the time required to achieve the adsorption equilibrium for both dyes was about 30 min, and the increase in temperature was not favorable to the adsorption process. It was worth noting that the adsorption capacity of ox-MWCNT-PER towards ARS dye was more significant than that towards AYR dye. And the maximum adsorption capacities for ARS and AYR were 257.73 mg g-1 and 45.39 mg g-1, respectively. The possible adsorption mechanism was also proposed, and the synergistic effects of the hydrogen bonding and the π-π electron stacking interactions between the adsorbents and adsorbates both contributed to the adsorption. It could be proposed that the ox-MWCNT-PER nanocomposite might have some positive effects in removing organic dyes from water treatment in the future.

Electro-optical and physic-mechanical properties of colored alicyclic polyimide

NASA Astrophysics Data System (ADS)

Kravtsova, V.; Umerzakova, M.; Korobova, N.; Timoshenkov, S.; Timoshenkov, V.; Orlov, S.; Iskakov, R.; Prikhodko, O.

2016-09-01

Main optical, thermal and mechanical properties of new compositions based on alicyclic polyimide and active bright red 6C synthetic dye have been studied. It was shown that the transmission ratio of the new material in the region of 400-900 nm and 2.0 wt.% dye concentration was around 60-70%. Thermal, mechanical and electrical properties of new colored compositions were comparable with the properties of original polyimide.

Protocol for vital dye staining of corneal endothelial cells.

PubMed

Park, Sunju; Fong, Alan G; Cho, Hyung; Zhang, Cheng; Gritz, David C; Mian, Gibran; Herzlich, Alexandra A; Gore, Patrick; Morganti, Ashley; Chuck, Roy S

2012-12-01

To describe a step-by-step methodology to establish a reproducible staining protocol for the evaluation of human corneal endothelial cells. Four procedures were performed to determine the best protocol. (1) To determine the optimal trypan blue staining method, goat corneas were stained with 4 dilutions of trypan blue (0.4%, 0.2%, 0.1%, and 0.05%) and 1% alizarin red. (2) To determine the optimal alizarin red staining method, goat corneas were stained with 2 dilutions of alizarin red (1% and 0.5%) and 0.2% trypan blue. (3) To ensure that trypan blue truly stains damaged cells, goat corneas were exposed to either 3% hydrogen peroxide or to balanced salt solution, and then stained with 0.2% trypan blue and 0.5% alizarin red. (4) Finally, fresh human corneal buttons were examined; 1 group was stained with 0.2% trypan blue and another group with 0.4% trypan blue. For the 4 procedures performed, the results are as follows: (1) trypan blue staining was not observed in any of the normal corneal samples; (2) 0.5% alizarin red demonstrated sharper cell borders than 1% alizarin red; (3) positive trypan blue staining was observed in the hydrogen peroxide exposed tissue in damaged areas; (4) 0.4% trypan blue showed more distinct positive staining than 0.2% trypan blue. We were able to determine the optimal vital dye staining conditions for human corneal endothelial cells using 0.4% trypan blue and 0.5% alizarin red.

The melting of native domain structure in effector activation of IgG studied by using congo red as a specific probe.

PubMed

Piekarska, B; Roterman, I; Rybarska, J; Koniczny, L; Kaszuba, J

1994-03-01

The nature of structural changes in IgG molecules associated with the binding to antigen and/or heat aggregation was studied using bis azo dye (Congo Red) as the specific probe. It was found, that protein conformation responsible for binding the dye represents an unfolding intermediate with properties corresponding to a molten globule state. The properties of the dye-protein complex reveal the signs of an unfolding of the peptide chain with simultaneously preserved relatively compact packing. Immunoglobulins which were induced by heating, or binding to antigen in order to form the complex with dye ligands, become more susceptible for digestion. The main peptide of molecular weight 30,000 D which appears in products was suggested to originate from a heavy chain after its splitting in the region of CH1 domain. The energetic evaluation of stability of IgG domains also indicates that CH1 is the least stable fragment of the heavy chain and its conformation may be destabilized first. It was concluded that destabilized tertiary packing of antibodies bound to antigen may favour the association of closely situated immunoglobulin molecules increasing the stability of the immune complex and influencing in the result its effector activity.

A review on applicability of naturally available adsorbents for the removal of hazardous dyes from aqueous waste.

PubMed

Sharma, Pankaj; Kaur, Harleen; Sharma, Monika; Sahore, Vishal

2011-12-01

The effluent water of many industries, such as textiles, leather, paper, printing, cosmetics, etc., contains large amount of hazardous dyes. There is huge number of treatment processes as well as adsorbent which are available for the processing of this effluent water-containing dye content. The applicability of naturally available low cast and eco-friendly adsorbents, for the removal of hazardous dyes from aqueous waste by adsorption treatment, has been reviewed. In this review paper, we have provided a compiled list of low-cost, easily available, safe to handle, and easy-to-dispose-off adsorbents. These adsorbents have been classified into five different categories on the basis of their state of availability: (1) waste materials from agriculture and industry, (2) fruit waste, (3) plant waste, (4) natural inorganic materials, and (5) bioadsorbents. Some of the treated adsorbents have shown good adsorption capacities for methylene blue, congo red, crystal violet, rhodamine B, basic red, etc., but this adsorption process is highly pH dependent, and the pH of the medium plays an important role in the treatment process. Thus, in this review paper, we have made some efforts to discuss the role of pH in the treatment of wastewater.

Method Of Signal Amplification In Multi-Chromophore Luminescence Sensors

DOEpatents

Levitsky, Igor A.; Krivoshlykov, Sergei G.

2004-02-03

A fluorescence-based method for highly sensitive and selective detection of analyte molecules is proposed. The method employs the energy transfer between two or more fluorescent chromophores in a carefully selected polymer matrix. In one preferred embodiment, signal amplification has been achieved in the fluorescent sensing of dimethyl methylphosphonate (DMMP) using two dyes, 3-aminofluoranthene (AM) and Nile Red (NR), in a hydrogen bond acidic polymer matrix. The selected polymer matrix quenches the fluorescence of both dyes and shifts dye emission and absorption spectra relative to more inert matrices. Upon DMMP sorption, the AM fluorescence shifts to the red at the same time the NR absorption shifts to the blue, resulting in better band overlap and increased energy transfer between chromophores. In another preferred embodiment, the sensitive material is incorporated into an optical fiber system enabling efficient excitation of the dye and collecting the fluorescent signal form the sensitive material on the remote end of the system. The proposed method can be applied to multichromophore luminescence sensor systems incorporating N-chromophores leading to N-fold signal amplification and improved selectivity. The method can be used in all applications where highly sensitive detection of basic gases, such as dimethyl methylphosphonate (DMMP), Sarin, Soman and other chemical warfare agents having basic properties, is required, including environmental monitoring, chemical industry and medicine.

Equilibrium and kinetic adsorption study of Basic Yellow 28 and Basic Red 46 by a boron industry waste.

PubMed

Olgun, Asim; Atar, Necip

2009-01-15

In this study, the adsorption characteristics of Basic Yellow 28 (BY 28) and Basic Red 46 (BR 46) onto boron waste (BW), a waste produced from boron processing plant were investigated. The equilibrium adsorption isotherms and kinetics were investigated. The adsorption equilibrium data were analyzed by using various adsorption isotherm models and the results have shown that adsorption behavior of two dyes could be described reasonably well by a generalized isotherm. Kinetic studies indicated that the kinetics of the adsorption of BY 28 and BR 46 onto BW follows a pseudo-second-order model. The result showed that the BW exhibited high-adsorption capacity for basic dyes and the capacity slightly decreased with increasing temperature. The maximum adsorption capacities of BY 28 and BR 46 are reported at 75.00 and 74.73mgg(-1), respectively. The dye adsorption depended on the initial pH of the solution with maximum uptake occurring at about pH 9 and electrokinetic behavior of BW. Activation energy of 15.23kJ/mol for BY 28 and 18.15kJ/mol for BR 46 were determined confirming the nature of the physisorption onto BW. These results indicate that BW could be employed as low-cost material for the removal of the textile dyes from effluents.

Ethnobotany of dye plants in Dong communities of China

PubMed Central

2014-01-01

Background Dyes derived from plants have an extensive history of use for coloring food and clothing in Dong communities and other indigenous areas in the uplands of China. In addition to use as coloring agents, Dong communities have historically utilized dye plants for their value for enhancing the nutritive, medicinal and preservative properties of foods. However, the persistence of plant-derived dyes and associated cultural practices and traditional knowledge is threatened with rapid socio-economic change in China. Research is needed to document the ethnobotany of dye plants in indigenous communities towards their conservation and potential commercialization as a sustainable means of supporting local development initiatives. Methods Semi-structured surveys on plants used for coloring agents and associated traditional knowledge were conducted in fifteen Dong villages of Tongdao County in Hunan Province of South Central China during 2011–2012. Transect walks were carried out with key informants identified from semi-structured surveys to collect samples and voucher specimens for each documented plant species for taxonomic identification. Results Dong households at the study sites utilize the flowers, bark, stems, tubers and roots of 13 plant species from 9 families as dyes to color their customary clothing and food. Out of the documented plants, a total of 7 are used for coloring food, 3 for coloring clothing and 3 for both food and clothing. Documented plants consist of 3 species that yield black pigments, 3 for brownish red/russet pigments, 3 for red pigments, 2 for dark blue pigments and 2 for yellow pigments. In addition to dyes, the plants have multiple uses including medicinal, ornamental, sacrificial, edible, and for timber. Conclusions The use of dyes derived from plants persists at the study sites for their important role in expressing Dong cultural identity through customary clothing and food. Further research is needed to evaluate the safety of dye plants, their efficacy in enhancing food items and their commercial potential. Conservation policies and management plans are called for to preserve these ethnobotanical resources in a sustainable manner that supports local livelihoods while maintaining cultural practices. PMID:24552267

Ethnobotany of dye plants in Dong communities of China.

PubMed

Liu, Yujing; Ahmed, Selena; Liu, Bo; Guo, Zhiyong; Huang, Weijuan; Wu, Xianjin; Li, Shenghua; Zhou, Jiangju; Lei, Qiyi; Long, Chunlin

2014-02-19

Dyes derived from plants have an extensive history of use for coloring food and clothing in Dong communities and other indigenous areas in the uplands of China. In addition to use as coloring agents, Dong communities have historically utilized dye plants for their value for enhancing the nutritive, medicinal and preservative properties of foods. However, the persistence of plant-derived dyes and associated cultural practices and traditional knowledge is threatened with rapid socio-economic change in China. Research is needed to document the ethnobotany of dye plants in indigenous communities towards their conservation and potential commercialization as a sustainable means of supporting local development initiatives. Semi-structured surveys on plants used for coloring agents and associated traditional knowledge were conducted in fifteen Dong villages of Tongdao County in Hunan Province of South Central China during 2011-2012. Transect walks were carried out with key informants identified from semi-structured surveys to collect samples and voucher specimens for each documented plant species for taxonomic identification. Dong households at the study sites utilize the flowers, bark, stems, tubers and roots of 13 plant species from 9 families as dyes to color their customary clothing and food. Out of the documented plants, a total of 7 are used for coloring food, 3 for coloring clothing and 3 for both food and clothing. Documented plants consist of 3 species that yield black pigments, 3 for brownish red/russet pigments, 3 for red pigments, 2 for dark blue pigments and 2 for yellow pigments. In addition to dyes, the plants have multiple uses including medicinal, ornamental, sacrificial, edible, and for timber. The use of dyes derived from plants persists at the study sites for their important role in expressing Dong cultural identity through customary clothing and food. Further research is needed to evaluate the safety of dye plants, their efficacy in enhancing food items and their commercial potential. Conservation policies and management plans are called for to preserve these ethnobotanical resources in a sustainable manner that supports local livelihoods while maintaining cultural practices.

Biodegradation and detoxification of textile azo dyes by bacterial consortium under sequential microaerophilic/aerobic processes

PubMed Central

Lade, Harshad; Kadam, Avinash; Paul, Diby; Govindwar, Sanjay

2015-01-01

Release of textile azo dyes to the environment is an issue of health concern while the use of microorganisms has proved to be the best option for remediation. Thus, in the present study, a bacterial consortium consisting of Providencia rettgeri strain HSL1 and Pseudomonas sp. SUK1 has been investigated for degradation and detoxification of structurally different azo dyes. The consortium showed 98-99 % decolorization of all the selected azo dyes viz. Reactive Black 5 (RB 5), Reactive Orange 16 (RO 16), Disperse Red 78 (DR 78) and Direct Red 81 (DR 81) within 12 to 30 h at 100 mg L-1 concentration at 30 ± 0.2 °C under microaerophilic, sequential aerobic/microaerophilic and microaerophilic/aerobic processes. However, decolorization under microaerophilic conditions viz. RB 5 (0.26 mM), RO 16 (0.18 mM), DR 78 (0.20 mM) and DR 81 (0.23 mM) and sequential aerobic/microaerophilic processes viz. RB 5 (0.08 mM), RO 16 (0.06 mM), DR 78 (0.07 mM) and DR 81 (0.09 mM) resulted into the formation of aromatic amines. In distinction, sequential microaerophilic/ aerobic process doesn’t show the formation of amines. Additionally, 62-72 % reduction in total organic carbon content was observed in all the dyes decolorized broths under sequential microaerophilic/aerobic processes suggesting the efficacy of method in mineralization of dyes. Notable induction within the levels of azoreductase and NADH-DCIP reductase (97 and 229 % for RB 5, 55 and 160 % for RO 16, 63 and 196 % for DR 78, 108 and 258 % for DR 81) observed under sequential microaerophilic/aerobic processes suggested their critical involvements in the initial breakdown of azo bonds, whereas, a slight increase in the levels of laccase and veratryl alcohol oxidase confirmed subsequent oxidation of formed amines. Also, the acute toxicity assay with Daphnia magna revealed the nontoxic nature of the dye-degraded metabolites under sequential microaerophilic/aerobic processes. As biodegradation under sequential microaerophilic/aerobic process completely detoxified all the selected textile azo dyes, further efforts should be made to implement such methods for large scale dye wastewater treatment technologies. PMID:26417357

WATER QUALITY AND TREATMENT CONSIDERATIONS FOR CEMENT-LINED AND A-C PIPE

EPA Science Inventory

Both cement mortar lined (CML) and asbestos-cement pipes (A-C) are widely used in many water systems. Cement linings are also commonly applied in-situ after pipe cleaning, usually to prevent the recurrence of red water or tuberculation problems. Unfortunately, little consideratio...

Plant Growth Absorption Spectrum Mimicking Light Sources

PubMed Central

Jou, Jwo-Huei; Lin, Ching-Chiao; Li, Tsung-Han; Li, Chieh-Ju; Peng, Shiang-Hau; Yang, Fu-Chin; Justin Thomas, K. R.; Kumar, Dhirendra; Chi, Yun; Hsu, Ban-Dar

2015-01-01

Plant factories have attracted increasing attention because they can produce fresh fruits and vegetables free from pesticides in all weather. However, the emission spectra from current light sources significantly mismatch the spectra absorbed by plants. We demonstrate a concept of using multiple broad-band as well as narrow-band solid-state lighting technologies to design plant-growth light sources. Take an organic light-emitting diode (OLED), for example; the resulting light source shows an 84% resemblance with the photosynthetic action spectrum as a twin-peak blue dye and a diffused mono-peak red dye are employed. This OLED can also show a greater than 90% resemblance as an additional deeper red emitter is added. For a typical LED, the resemblance can be improved to 91% if two additional blue and red LEDs are incorporated. The approach may facilitate either an ideal use of the energy applied for plant growth and/or the design of better light sources for growing different plants. PMID:28793503

The discrimination of colored acrylic, cotton, and wool textile fibers using micro-Raman spectroscopy. Part 1: in situ detection and characterization of dyes.

PubMed

Buzzini, Patrick; Massonnet, Genevieve

2013-11-01

Raman spectroscopy has been applied to characterize fiber dyes and determine the discriminating ability of the method. Black, blue, and red acrylic, cotton, and wool samples were analyzed. Four excitation sources were used to obtain complementary responses in the case of fluorescent samples. Fibers that did not provide informative spectra using a given laser were usually detected using another wavelength. For any colored acrylic, the 633-nm laser did not provide Raman information. The 514-nm laser provided the highest discrimination for blue and black cotton, but half of the blue cottons produced noninformative spectra. The 830-nm laser exhibited the highest discrimination for red cotton. Both visible lasers provided the highest discrimination for black and blue wool, and NIR lasers produced remarkable separation for red and black wool. This study shows that the discriminating ability of Raman spectroscopy depends on the fiber type, color, and the laser wavelength. © 2013 American Academy of Forensic Sciences.

Effects of dissolved oxygen on dye removal by zero-valent iron.

PubMed

Wang, Kai-Sung; Lin, Chiou-Liang; Wei, Ming-Chi; Liang, Hsiu-Hao; Li, Heng-Ching; Chang, Chih-Hua; Fang, Yung-Tai; Chang, Shih-Hsien

2010-10-15

Effects of dissolved oxygen concentrations on dye removal by zero-valent iron (Fe(0)) were investigated. The Vibrio fischeri light inhibition test was employed to evaluate toxicity of decolorized solution. Three dyes, Acid Orange 7 (AO7, monoazo), Reactive Red 120 (RR120, diazo), and Acid Blue 9 (AB9, triphenylmethane), were selected as model dyes. The dye concentration and Fe(0) dose used were 100 mg L(-1) and 30 g L(-1), respectively. Under anoxic condition, the order for dye decolorization was AO7>RR120>AB9. An increase in the dissolved oxygen concentrations enhanced decolorization and chemical oxygen demand (COD) removal of the three dyes. An increase in gas flow rates also improved dye and COD removals by Fe(0). At dissolved oxygen of 6 mg L(-1), more than 99% of each dye was decolorized within 12 min and high COD removals were obtained (97% for AO7, 87% for RR120, and 93% for AB9). The toxicity of decolorized dye solutions was low (I(5)<40%). An increase in DO concentrations obviously reduced the toxicity. When DO above 2 mg L(-1) was applied, low iron ion concentration (13.6 mg L(-1)) was obtained in the decolorized AO7 solution. 2010 Elsevier B.V. All rights reserved.

Polychromatophilia

MedlinePlus

... than normal with certain dyes. The extra staining is due to too many immature red blood cells (RBCs) called reticulocytes. These cells have a blue-colored center. Increased reticulocytes are the result of ...

Sonocatalytic rapid degradation of Congo red dye from aqueous solution using magnetic Fe0/polyaniline nanofibers.

PubMed

Das, Raghunath; Bhaumik, Madhumita; Giri, Somnath; Maity, Arjun

2017-07-01

Nano-sized magnetic Fe 0 /polyaniline (Fe 0 /PANI) nanofibers were used as an effective material for sonocatalytic degradation of organic anionic Congo red (CR) dye. Fe 0 /PANI , was synthesized via reductive deposition of nano-Fe 0 onto the PANI nanofibers at room temperature. Prepared catalyst was characterized using HR-TEM, FE-SEM, XRD, FTIR instruments. The efficacy of catalyst in removing CR was assessed colorimetrically using UV-visible spectroscopy under different experimental conditions such as % of Fe 0 loading into the composite material, solution pH, initial concentration of dye, catalyst dosage, temperature and ultrasonic power. The optimum conditions for sonocatalytic degradation of CR were obtained at catalyst concentrations=500mg.L -1 , concentration of CR=200ppm, solution pH=neutral (7.0), temperature=30°C, % of Fe 0 loading=30% and 500W ultrasonic power. The experimental results showed that ultrasonic process could remove 98% of Congo red within 30min with higher Q max value (Q max =446.4 at 25°C). The rate of degradation of CR dye was much faster in this ultrasonic technique rather than conventional adsorption process. The degradation efficiency declined with the addition of common inorganic salts (NaCl, Na 2 CO 3 , Na 2 SO 4 and Na 3 PO 4 ). The rate of degradation suppressed more with increasing salt concentration. Kinetic and isotherm studies indicated that the degradation of CR provides pseudo-second order rate kinetic and Langmuir isotherm model compared to all other models tested. The excellent high degradation capacity of Fe 0 /PANI under ultrasonic irradiation can be explained on the basis of the formation of active hydroxyl radicals (OH) and subsequently a series of free radical reactions. Copyright © 2017 Elsevier B.V. All rights reserved.

Intratracheal administration of bacterial lipopolysaccharide elicits pulmonary hypertension in broilers with primed airways.

PubMed

Lorenzoni, A G; Wideman, R F

2008-04-01

Broilers reared under commercial conditions inhale irritant gases and aerosolized particulates contaminated with gram-negative bacteria and bacterial lipopolysaccharide (LPS). Previous studies demonstrated that i.v. injections of LPS can trigger an increase in the pulmonary arterial pressure (PAP); however, the pulmonary hemodynamic response to aerosolized LPS entering via the most common route, the respiratory tract, had not been evaluated in broilers. In experiment 1, broilers reared on new wood shavings litter in clean environmental chambers either were not pretreated (control group) or were pretreated via aerosol inhalation of substances (food color dyes and propylene glycol) known to sensitize the airways. One day later, the broilers were anesthetized, catheterized to record the PAP, and an intratracheal aerosol spray of LPS (1 mL of 2 mg/mL of LPS) was administered. Broilers in the control group as well as broilers pretreated with aerosolized distilled water or yellow and blue food color dyes did not develop pulmonary hypertension (PH; an increase in PAP) after the intratracheal spray of LPS, whereas broilers that had been pretreated with red food color did develop PH in response to intratracheal LPS. In experiment 2, birds raised under commercial conditions on used wood shavings litter developed PH in response to intratracheal LPS regardless of whether they had been pretreated with aerosolized red food color dye. In experiment 3, broilers reared in clean environmental chambers on new wood shavings litter were used to demonstrate that Red Dye #3 and propylene glycol are capable of priming the responsiveness of the airways to a subsequent intratracheal LPS challenge. Common air contaminants such as LPS can result in PH leading to pulmonary hypertension syndrome (ascites) in broilers with appropriately primed airways.

Determination of allura red in some food samples by adsorptive stripping voltammetry.

PubMed

Alghamdi, Ahmad H

2005-01-01

Square wave (SW) voltammetry was used to explore the adsorption properties of the food additive dye Allura Red on a hanging mercury drop electrode (HMDE). By using the adsorptive stripping voltammetric approach, we developed a sensitive electroanalytical method for the determination of this azo dye. A well-developed voltammetric peak probably related to the cathodic reduction of the azo moiety was obtained in pH 9 Britton-Robinson (B-R) buffer at 613 mV. Cyclic voltammetric studies indicated that the reduction process was irreversible and primarily controlled by adsorption. The adsorptive voltammetric signal was evaluated with respect to various experimental conditions; the optimized values were supporting electrolyte, B-R buffer; pH 11; accumulation time, 180 s; accumulation potential, 0.0 V; scan rate, 900 mV/s; pulse amplitude, 75 mV; and SW frequency, 90 Hz. Adsorptive voltammetric peak current showed a linear response for Allura Red in the concentration range of 2.5 x 10(-8) to 2.0 x 10(-7) mol/L (r = 0.998). The limit of detection was 8.5 x 10(-9) mol/L (4.2 ng/mL), the precision in terms of relative standard deviation was 1.3%, and the mean recovery was 102%. Possible interferences by several substances usually present in food products such as food additive azo dyes (E110, E102), gelatin, natural and artificial sweeteners, preservatives, and antioxidants were also evaluated. The proposed electrochemical procedure was successfully applied to the determination of this food dye in commercially available candy and a soft drink. The results were compared by statistical evaluation with those obtained by a reference spectrophotometric method.

Micro-encapsulated sensors for in vivo assessment of the oxidative stress in aquatic organisms

NASA Astrophysics Data System (ADS)

Sadovoy, Anton; Teh, Cathleen; Escobar, Marco; Meglinski, Igor; Korzh, Vladimir

2011-10-01

Oxidative stress results from an imbalance between the production and detoxification of reactive oxygen spices (ROS). ROS are natural byproducts of normal metabolism of oxygen and have important roles in cell signaling and homeostasis. Many heart related diseases like heart failure and myocardial infarction develop as a result of oxidative stress. Current treatment cannot improve the progressive decline in heart function experienced by all patients. Therefore heart failure is the cause of around 25% of all deaths in the Asia Pacific region. Thus any step taken to address the oxidative stress problem is essential for enhancing human health and improve their quality of life. Current approach is dedicated to develop micron-size oxidation stress-sensor for in-vivo measuring level of ROS in KillerRed expressing transgenic zebrafish larvae. Central to our investigation is the light-inducible heart failure animal model we developed in zebrafish that expressed KillerRed in the heart. By utilizing the photosensitizer properties of KillerRed to produce ROS upon green light illumination, heart failure can be repeatedly induced in a non-invasive manner. Importantly, the use of this biological platform permits the development of physiologically sensitive ROS sensor and identifies efficient antioxidants that improve heart contractility. The biosensor approach is based on utilizing biocompatible polyelectrolyte microcapsules as a carry of fluorescent dyes sensitive to amount of reactive oxygen spices. Microcapsule prevents dye diffusion in tissue that makes use toxic dyes possible. Microcapsule's wall is permeable for environment with size less than 500 Da. The oxidation stress-sensors are injected directly in zebrafish pericardium with further circulation along blood system. Detecting of ROS is obtained by using laser scanning microscopy by illuminating oxidation stress-sensors and detecting changing excitation signal from the fluorescent dye.

Micro-encapsulated sensors for in vivo assessment of the oxidative stress in aquatic organisms

NASA Astrophysics Data System (ADS)

Sadovoy, Anton; Teh, Cathleen; Escobar, Marco; Meglinski, Igor; Korzh, Vladimir

2012-03-01

Oxidative stress results from an imbalance between the production and detoxification of reactive oxygen spices (ROS). ROS are natural byproducts of normal metabolism of oxygen and have important roles in cell signaling and homeostasis. Many heart related diseases like heart failure and myocardial infarction develop as a result of oxidative stress. Current treatment cannot improve the progressive decline in heart function experienced by all patients. Therefore heart failure is the cause of around 25% of all deaths in the Asia Pacific region. Thus any step taken to address the oxidative stress problem is essential for enhancing human health and improve their quality of life. Current approach is dedicated to develop micron-size oxidation stress-sensor for in-vivo measuring level of ROS in KillerRed expressing transgenic zebrafish larvae. Central to our investigation is the light-inducible heart failure animal model we developed in zebrafish that expressed KillerRed in the heart. By utilizing the photosensitizer properties of KillerRed to produce ROS upon green light illumination, heart failure can be repeatedly induced in a non-invasive manner. Importantly, the use of this biological platform permits the development of physiologically sensitive ROS sensor and identifies efficient antioxidants that improve heart contractility. The biosensor approach is based on utilizing biocompatible polyelectrolyte microcapsules as a carry of fluorescent dyes sensitive to amount of reactive oxygen spices. Microcapsule prevents dye diffusion in tissue that makes use toxic dyes possible. Microcapsule's wall is permeable for environment with size less than 500 Da. The oxidation stress-sensors are injected directly in zebrafish pericardium with further circulation along blood system. Detecting of ROS is obtained by using laser scanning microscopy by illuminating oxidation stress-sensors and detecting changing excitation signal from the fluorescent dye.

Contrasting guest binding interaction of cucurbit[7-8]urils with neutral red dye: controlled exchange of multiple guests.

PubMed

Shaikh, Mhejabeen; Choudhury, Sharmistha Dutta; Mohanty, Jyotirmayee; Bhasikuttan, Achikanath C; Pal, Haridas

2010-07-14

Interactions among macrocyclic hosts and dyes/drugs have been explored extensively for their direct usage in controlled uptake and release of large number of potential drug molecules. In this paper we report the non-covalent interaction of cucurbit[8]uril macrocycle (CB8) with a biologically important dye, neutral red, by absorption and fluorescence spectroscopy. A comparative analysis with the complexation behaviour of the dye with CB7, the lower homologue of CB8, indicates contrasting guest binding behaviour with significant changes in the photophysical characteristics of the dye. While CB7 interaction leads to a 1 ratio 1 stoichiometry resulting in approximately 6 fold enhancement in the fluorescence emission of the dye, CB8 displays signatures for a 1 ratio 2 host-guest stoichiometry with drastic reduction in the fluorescence emission. Apart from the evaluation of approximately 2 unit shift in the protolytic equilibrium on complexation (pK(a) shift), the measurements with tryptophan established a selective guest exchange to favour a co-localized dimer inside the CB8 cavity. In a protein medium (BSA), the 1 ratio 2 complex was converted to a 1 ratio 1 ratio 1 CB8-NRH(+)-BSA complex. The finding that NRH(+) can be transferred from CB8 to BSA, even though the binding constant for NRH(+)-CB8 is much higher than NRH(+)-BSA, is projected for a controlled slow release of NRH(+) towards BSA. Since the release and activity of drugs can be controlled by regulating the protolytic equilibrium, the macromolecular encapsulation and release of NRH(+) demonstrated here provide information relevant to host-guest based drug delivery systems and its applications.

Removal of azo dye using Fenton and Fenton-like processes: Evaluation of process factors by Box-Behnken design and ecotoxicity tests.

PubMed

Fernandes, Neemias Cintra; Brito, Lara Barroso; Costa, Gessyca Gonçalves; Taveira, Stephânia Fleury; Cunha-Filho, Marcílio Sérgio Soares; Oliveira, Gisele Augusto Rodrigues; Marreto, Ricardo Neves

2018-06-06

The conventional treatment of textile effluents is usually inefficient in removing azo dyes and can even generate more toxic products than the original dyes. The aim of the present study was to optimize the process factors in the degradation of Disperse Red 343 by Fenton and Fenton-like processes, as well as to investigate the ecotoxicity of the samples treated under optimized conditions. A Box-Behnken design integrated with the desirability function was used to optimize dye degradation, the amount of residual H 2 O 2 [H 2 O 2residual ], and the ecotoxicity of the treated samples (lettuce seed, Artemia salina, and zebrafish in their early-life stages). Dye degradation was affected only by catalyst concentration [Fe] in both the Fenton and Fenton-like processes. In the Fenton reaction, [H 2 O 2residual ] was significantly affected by initial [H 2 O 2 ] and its interaction with [Fe]; however, in the Fenton-like reaction, it was affected by initial [H 2 O 2 ] only. A. salina mortality was affected by different process factors in both processes, which suggests the formation of different toxic products in each process. The desirability function was applied to determine the best process parameters and predict the responses, which were confirmed experimentally. Optimal conditions facilitated the complete degradation of the dye without [H 2 O 2residual ] or toxicity for samples treated with the Fenton-like process, whereas the Fenton process induced significant mortality for A. salina. Results indicate that the Fenton-like process is superior to the Fenton reaction to degrade Disperse Red 343. Copyright © 2018 Elsevier B.V. All rights reserved.

Use of cellulose-based wastes for adsorption of dyes from aqueous solutions.

PubMed

Annadurai, Gurusamy; Juang, Ruey-Shin; Lee, Duu-Jong

2002-06-10

Low-cost banana and orange peels were prepared as adsorbents for the adsorption of dyes from aqueous solutions. Dye concentration and pH were varied. The adsorption capacities for both peels decreased in the order methyl orange (MO) > methylene blue (MB) > Rhodamine B (RB) > Congo red (CR) > methyl violet (MV) > amido black 10B (AB). The isotherm data could be well described by the Freundlich and Langmuir equations in the concentration range of 10-120 mg/l. An alkaline pH was favorable for the adsorption of dyes. Based on the adsorption capacity, it was shown that banana peel was more effective than orange peel. Kinetic parameters of adsorption such as the Langergren rate constant and the intraparticle diffusion rate constant were determined. For the present adsorption process intraparticle diffusion of dyes within the particle was identified to be rate limiting. Both peel wastes were shown to be promising materials for adsorption removal of dyes from aqueous solutions.

Cellulose nanocrystal-reinforced keratin bioadsorbent for effective removal of dyes from aqueous solution.

PubMed

Song, Kaili; Xu, Helan; Xu, Lan; Xie, Kongliang; Yang, Yiqi

2017-05-01

High-efficiency and recyclable three-dimensional bioadsorbents were prepared by incorporating cellulose nanocrystal (CNC) as reinforcements in keratin sponge matrix to remove dyes from aqueous solution. Adsorption performance of dyes by CNC-reinforced keratin bioadsorbent was improved significantly as a result of adding CNC as filler. Batch adsorption results showed that the adsorption capacities for Reactive Black 5 and Direct Red 80 by the bioadsorbent were 1201 and 1070mgg -1 , respectively. The isotherms and kinetics for adsorption of both dyes on bioadsorbent followed the Langmuir isotherm model and pseudo-second order model, respectively. Desorption and regeneration experiments showed that the removal efficiencies of the bioadsorbent for both dyes could remain above 80% at the fifth recycling cycles. Moreover, the bioadsorbent possessed excellent packed-bed column operation performance. Those results suggested that the adsorbent could be considered as a high-performance and promising candidate for dye wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fluorescence of acridinic dyes in anionic surfactant solution

NASA Astrophysics Data System (ADS)

Pereira, Robson Valentim; Gehlen, Marcelo Henrique

2005-10-01

The interaction of the cationic dyes acridine, 9-aminoacridine (9AA), and proflavine, with sodium dodecyl sulfate (SDS) was studied by electronic absorption, steady-state and time-resolved fluorescence spectroscopies. The dyes interact with SDS in the pre-micellar region leading in two cases to dimerization in dye-surfactant aggregates, but with distinct molecular arrangements. For proflavine, the observed red shift of the electronic absorption band indicates the presence of J-aggregate, which are nonfluorescent. In the case of 9AA, the aggregates were characterized as nonspecific (neither J- nor H-type is spectroscopically observed). The time-resolved emission spectra gives evidences of the presence of weakly bound dimers by the recovery of three defined decay times by global analysis: dye monomer ( τ1 = 16.4 ns), dimer ( τ2 = 7.1 ns), and a faster component ( τ3 = 2.1 ns) ascribed to intracluster energy migration between monomer and dimer. Acridine has a weak interaction with SDS forming only an ion pair without further self-aggregation of the dye.

Fluorescence of acridinic dyes in anionic surfactant solution.

PubMed

Pereira, Robson Valentim; Gehlen, Marcelo Henrique

2005-10-01

The interaction of the cationic dyes acridine, 9-aminoacridine (9AA), and proflavine, with sodium dodecyl sulfate (SDS) was studied by electronic absorption, steady-state and time-resolved fluorescence spectroscopies. The dyes interact with SDS in the pre-micellar region leading in two cases to dimerization in dye-surfactant aggregates, but with distinct molecular arrangements. For proflavine, the observed red shift of the electronic absorption band indicates the presence of J-aggregate, which are nonfluorescent. In the case of 9AA, the aggregates were characterized as nonspecific (neither J- nor H-type is spectroscopically observed). The time-resolved emission spectra gives evidences of the presence of weakly bound dimers by the recovery of three defined decay times by global analysis: dye monomer (tau1 = 16.4 ns), dimer (tau2 = 7.1 ns), and a faster component (tau3 = 2.1 ns) ascribed to intracluster energy migration between monomer and dimer. Acridine has a weak interaction with SDS forming only an ion pair without further self-aggregation of the dye.

Application of fluorescence resonance energy transfer techniques to the study of lectin-binding site distribution on Paramecium primaurelia (Protista, Ciliophora) cell surface.

PubMed

Locatelli, D; Delmonte Corrado, M U; Politi, H; Bottiroli, G

1998-01-01

Fluorescence resonance energy transfer (FRET) is a photophysical phenomenon occurring between the molecules of two fluorochromes with suitable spectral characteristics (donor-acceptor dye pair), and consisting in an excitation energy migration through a non-radiative process. Since the efficiency of the process is strictly dependent on the distance and reciprocal orientation of the donor and acceptor molecules, FRET-based techniques can be successfully applied to the study of biomolecules and cell component organisation and distribution. These techniques have been employed in studying Paramecium primaurelia surface membrane for the reciprocal distribution of N-acetylneuraminic acid (NeuAc) and N-acetylglucosamine (GlcNAc) glycosidic residues, which were found to be involved in mating cell pairing. NeuAc and GlcNAc were detected by their specific binding lectins, Limulus polyphemus agglutinin (LPA) and wheat germ agglutinin (WGA), respectively. Microspectrofluorometric analysis afforded the choice of fluorescein isothiocyanate and Texas red conjugated with LPA and WGA, respectively, as a suitable donor-acceptor couple efficiently activating FRET processes. Studies performed both in solution and in cells allowed to define the experimental conditions favourable for a FRET analysis. The comparative study carried out both on the conjugating-region and the non conjugating region of the surface membrane, indicates that FRET distribution appears quite homogeneous in mating-competent mating type (mt) I, whereas, in mating-competent mt II cells, FRET distribution seems to be preferentially localised on the conjugating-region functionally involved in mating cell pairing. This difference in the distribution of lectin-binding sites is suggested to be related to mating-competence acquisition.

Comparative Studies on Dyeability with Direct, Acid and Reactive Dyes after Chemical Modification of Jute with Mixed Amino Acids Obtained from Extract of Waste Soya Bean Seeds

NASA Astrophysics Data System (ADS)

Bhaumik, Nilendu Sekhar; Konar, Adwaita; Roy, Alok Nath; Samanta, Ashis Kumar

2017-12-01

Jute fabric was treated with mixed natural amino acids obtained from waste soya bean seed extract for chemical modification of jute for its cataionization and to enhance its dyeability with anionic dyes (like direct, reactive and acid dye) as well enabling soya modified jute for salt free dyeing with anionic reactive dyes maintaining its eco-friendliness. Colour interaction parameters including surface colour strength were assessed and compared for both bleached and soya-modified jute fabric for reactive dyeing and compared with direct and acid dye. Improvement in K/S value (surface colour strength) was observed for soya-modified jute even in absence of salt applied in dye bath for reactive dyes as well as for direct and acid dyes. In addition, reactive dye also shows good dyeability even in acid bath in salt free conditions. Colour fastness to wash was evaluated for bleached and soya-modified jute fabric after dyeing with direct, acid and reactive dyes are reported. Treatment of jute with soya-extracted mixed natural amino acids showed anchoring of some amino/aldemine groups on jute cellulosic polymer evidenced from Fourier Transform Infra-Red (FTIR) Spectroscopy. This amino or aldemine group incorporation in bleached jute causes its cationization and hence when dyed in acid bath for reactive dye (instead of conventional alkali bath) showed dye uptake for reactive dyes. Study of surface morphology by Scanning Electron Microscopy (SEM) of said soya-modified jute as compared to bleached jute was studied and reported.

Adsorption mechanism for xanthene dyes to cellulose granules.

PubMed

Tabara, Aya; Yamane, Chihiro; Seguchi, Masaharu

2012-01-01

The xanthene dyes, erythrosine, phloxine, and rose bengal, were adsorbed to charred cellulose granules. The charred cellulose granules were preliminarily steeped in ionic (NaOH, NaCl, KOH, KCl, and sodium dodecyl sulfate (SDS)), nonionic (glucose, sucrose, and ethanol), and amphipathic sucrose fatty acid ester (SFAE) solutions, and adsorption tests on the dye to the steeped and charred cellulose granules were conducted. Almost none of the dye was adsorbed when the solutions of ionic and amphipathic molecules were used, but were adsorbed in the case of steeping in the nonionic molecule solutions. Thin-layer chromatography (TLC) and the Fourier transform infra-red (FT-IR) profiles of SFAE which was adsorbed to the charred cellulose granules and extracted by ethyl ether suggested the presence of hydrophobic sites on the surface of the charred cellulose granules. We confirmed that the xanthene dyes could bind to the charred cellulose granules by ionic and hydrophobic bonds.

Response surface methodological approach for the decolorization of simulated dye effluent using Aspergillus fumigatus fresenius.

PubMed

Sharma, Praveen; Singh, Lakhvinder; Dilbaghi, Neeraj

2009-01-30

The aim of our research was to study, effect of temperature, pH and initial dye concentration on decolorization of diazo dye Acid Red 151 (AR 151) from simulated dye solution using a fungal isolate Aspergillus fumigatus fresenius have been investigated. The central composite design matrix and response surface methodology (RSM) have been applied to design the experiments to evaluate the interactive effects of three most important operating variables: temperature (25-35 degrees C), pH (4.0-7.0), and initial dye concentration (100-200 mg/L) on the biodegradation of AR 151. The total 20 experiments were conducted in the present study towards the construction of a quadratic model. Very high regression coefficient between the variables and the response (R(2)=0.9934) indicated excellent evaluation of experimental data by second-order polynomial regression model. The RSM indicated that initial dye concentration of 150 mg/L, pH 5.5 and a temperature of 30 degrees C were optimal for maximum % decolorization of AR 151 in simulated dye solution, and 84.8% decolorization of AR 151 was observed at optimum growth conditions.

The influence of changes in blood flow on the accuracy of pulse oximetry in humans.

PubMed

Vegfors, M; Lindberg, L G; Lennmarken, C

1992-05-01

Oxygen saturation (SpO2) was measured with a pulse oximeter in ten healthy, young men breathing air. A pulse oximeter probe was attached to the second toe and a laser Doppler probe to the first toe of the same foot for measurement of changes in peripheral blood flow. The pulse oximeter and laser Doppler readings were simultaneously compared when the foot was positioned 40 cm (position 1) above heart level, elevated 10 cm (position 2) above heart level and horizontally at heart level (position 3). Using this experimental human model, we achieved various blood flows. The AC and DC optical signals used for determination of oxygen saturation were recorded from the pulse oximeter and analysed. There was a significant increase (P less than 0.05) between position 1 and 3 in blood flow as measured by the laser Doppler flow meter. The corresponding pulse oximeter readings of haemoglobin saturation also increased significantly (P less than 0.05) comparing these two leg positions. Analysing the AC- and DC optical signals, the AC value of infrared light increased considerably, while the AC value of the red light decreased slightly. The DC values of red and infrared light did not change significantly. In summary, when blood flow was decreased, the ratio of red to infrared transmitted light was changed, resulting in a low SpO2 reading.

Cold Pad-Batch dyeing method for cotton fabric dyeing with reactive dyes using ultrasonic energy.

PubMed

Khatri, Zeeshan; Memon, Muhammad Hanif; Khatri, Awais; Tanwari, Anwaruddin

2011-11-01

Reactive dyes are vastly used in dyeing and printing of cotton fibre. These dyes have a distinctive reactive nature due to active groups which form covalent bonds with -OH groups of cotton through substitution and/or addition mechanism. Among many methods used for dyeing cotton with reactive dyes, the Cold Pad Batch (CPB) method is relatively more environment friendly due to high dye fixation and non requirement of thermal energy. The dyed fabric production rate is low due to requirement of at least twelve hours batching time for dye fixation. The proposed CPB method for dyeing cotton involves ultrasonic energy resulting into a one third decrease in batching time. The dyeing of cotton fibre was carried out with CI reactive red 195 and CI reactive black 5 by conventional and ultrasonic (US) method. The study showed that the use of ultrasonic energy not only shortens the batching time but the alkalis concentrations can considerably be reduced. In this case, the colour strength (K/S) and dye fixation (%F) also enhances without any adverse effect on colour fastness of the dyed fabric. The appearance of dyed fibre surface using scanning electron microscope (SEM) showed relative straightening of fibre convolutions and significant swelling of the fibre upon ultrasonic application. The total colour difference values ΔE (CMC) for the proposed method, were found within close proximity to the conventionally dyed sample. Copyright © 2011 Elsevier B.V. All rights reserved.

Nondestructive identification for red ink entries of seals by Raman and Fourier transform infrared spectrometry.

PubMed

Wang, Xiang-Feng; Yu, Jing; Zhang, Ai-Lan; Zhou, Dai-Wei; Xie, Meng-Xia

2012-11-01

Determination of the red ink entries of seals on documents can provide valuable evidences for solving related crimes, distinguishing the truth of artworks, and so establishment of nondestructive approaches would play a key role in forensic analysis and related aspects. Raman and FT-IR spectroscopy have been applied for analyzing 105 kinds of red ink entries on documents. The dye components of the ink entries were identified by FT-Raman and confocal Raman microspectroscopy, and then the ink entries were classified into four groups based on these dye components. The ink entries were further discriminated by their FT-IR spectra according to adsorption peaks of the main components, the relative intensities of the characteristic bands and the profiles of the spectra. The results showed that 70 ink entries out of 105 have been individually identified and the remaining 35 ink entries can be divided into 13 subclasses. Combination of Raman and FT-IR spectroscopic methods can provide a powerful nondestructive discriminating tool for identification of the red ink entries of seals on papers. These approaches would have potential application in archeology, art and forensic science. Copyright © 2012 Elsevier B.V. All rights reserved.

Spectroscopic and microcalorimetric studies on the molecular binding of food colorant acid red 27 with deoxyribonucleic acid.

PubMed

Basu, Anirban; Kumar, Gopinatha Suresh

2016-08-01

Interaction of the food colorant acid red 27 with double stranded DNA was investigated using spectroscopic and calorimetric methods. Absorbance and fluorescence studies suggested an intimate binding interaction between the dye and DNA. The quantum efficiency value testified an effective energy transfer from the DNA base pairs to the dye molecules. Minor groove displacement assay with Hoechst 33258 revealed that the binding occurs in the minor groove of DNA. Circular dichroism studies revealed that acid red 27 induces moderate conformational perturbations in DNA. Results of calorimetric studies suggested that the complexation process was driven largely by positive entropic contribution with a smaller favorable enthalpy contribution. The equilibrium constant of the binding was calculated to be (3.04 ± 0.09) × 10(4)  M(-1) at 298.15 K. Negative heat capacity value along with the enthalpy-entropy compensation phenomenon established the involvement of dominant hydrophobic forces in the binding process. Differential scanning calorimetry studies presented evidence for an increased thermal stability of DNA on binding of acid red 27. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Spectroscopy and laser action of the "red perylimide dye" in various solvents

NASA Astrophysics Data System (ADS)

Gvishi, R.; Reisfeld, R.; Burshtein, Z.

1993-10-01

Optical properties of the red perylimide laser dye in various solvents are studied. The absorption spectrum exhibits two main bands, in the ranges 480-600 and 400-460 nm, due to the S 0-S 1 and S 0-S 2 transition. The fluorescence spectrum is a mirror image of the S 0-S 1 absorption (shift of ˜ 30-50 nm). The Stokes shift increases with solvent polarity. Such dye-solvent interactions are compared to theoretical predictions. The fluorescence quantum yields approaches unity in all the solvents studied. Laser tunability around 30 nm was obtained each time, covering the spectral range 580-640 nm. This interval is important for medical applications in photodynamic therapy and fluorescence diagnostics. The laser threshold energy varied from 0.35 mJ/pulse in cyclohexane to 1.87 mJ/pulse in methanol, and the slope efficiency from about 6.6% in methanol to 14% in xylenes. The laser output was stable for several hours of operation under an average pump energy of about 20 mJ/pulse at 1 Hz repetition rate, without flow.

Optimization of Biosorptive Removal of Dye from Aqueous System by Cone Shell of Calabrian Pine

PubMed Central

Deniz, Fatih

2014-01-01

The biosorption performance of raw cone shell of Calabrian pine for C.I. Basic Red 46 as a model azo dye from aqueous system was optimized using Taguchi experimental design methodology. L9 (33) orthogonal array was used to optimize the dye biosorption by the pine cone shell. The selected factors and their levels were biosorbent particle size, dye concentration, and contact time. The predicted dye biosorption capacity for the pine cone shell from Taguchi design was obtained as 71.770 mg g−1 under optimized biosorption conditions. This experimental design provided reasonable predictive performance of dye biosorption by the biosorbent (R 2: 0.9961). Langmuir model fitted better to the biosorption equilibrium data than Freundlich model. This displayed the monolayer coverage of dye molecules on the biosorbent surface. Dubinin-Radushkevich model and the standard Gibbs free energy change proposed physical biosorption for predominant mechanism. The logistic function presented the best fit to the data of biosorption kinetics. The kinetic parameters reflecting biosorption performance were also evaluated. The optimization study revealed that the pine cone shell can be an effective and economically feasible biosorbent for the removal of dye. PMID:25405213

High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation.

PubMed

An, Alicia Kyoungjin; Guo, Jiaxin; Jeong, Sanghyun; Lee, Eui-Jong; Tabatabai, S Assiyeh Alizadeh; Leiknes, TorOve

2016-10-15

This study investigated the applicability of membrane distillation (MD) to treat dyeing wastewater discharged by the textile industry. Four different dyes containing methylene blue (MB), crystal violet (CV), acid red 18 (AR18), and acid yellow 36 (AY36) were tested. Two types of hydrophobic membranes made of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) were used. The membranes were characterized by testing against each dye (foulant-foulant) and the membrane-dye (membrane-foulant) interfacial interactions and their mechanisms were identified. The MD membranes possessed negative charges, which facilitated the treatment of acid and azo dyes of the same charge and showed higher fluxes. In addition, PTFE membrane reduced the wettability with higher hydrophobicity of the membrane surface. The PTFE membrane evidenced especially its resistant to dye absorption, as its strong negative charge and chemical structure caused a flake-like (loose) dye-dye structure to form on the membrane surface rather than in the membrane pores. This also enabled the recovery of flux and membrane properties by water flushing (WF), thereby direct-contact MD with PTFE membrane treating 100 mg/L of dye mixtures showed stable flux and superior color removal during five days operation. Thus, MD shows a potential for stable long-term operation in conjunction with a simple membrane cleaning process, and its suitability in dyeing wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation.

PubMed

Oon, Yoong-Sin; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Oon, Yoong-Ling; Lehl, Harvinder Kaur; Thung, Wei-Eng; Nordin, Noradiba

2017-03-05

Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m 2 , corresponding to current density of 120.24mA/m 2 . The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

Alkali, thermo and halo tolerant fungal isolate for the removal of textile dyes.

PubMed

Kaushik, Prachi; Malik, Anushree

2010-11-01

In the present study potential of a fungal isolate Aspergillus lentulusFJ172995, was investigated for the removal of textile dyes. The removal percentages of dyes such as Acid Navy Blue, Orange-HF, Fast Red A, Acid Sulphone Blue and Acid Magenta were determined as 99.43, 98.82, 98.75, 97.67 and 69.98, respectively. None of the dyes inhibited the growth of A. lentulus. Detailed studies on growth kinetics, mechanism of dye removal and effect of different parameters on dye removal were conducted using Acid Navy Blue dye. It was observed that A. lentulus could completely remove Acid Navy Blue even at high initial dye concentrations, up to 900 mg/L. Highest uptake capacity of 212.92 mg/g was observed at an initial dye concentration of 900 mg/L. Dye removing efficiency was not altered with the variation of pH; and biomass production as well as dye removal was favored at higher temperatures. Dye removal was also efficient even at high salt concentration. Through growth kinetics studies it was observed that the initial exponential growth phase coincided with the phase of maximal dye removal. Microscopic studies suggest that bioaccumulation along with biosorption is the principle mechanism involved in dye removal by A. lentulus. Thus, it is concluded that being alkali, thermo and halo tolerant, A. lentulus isolate has a great potential to be utilized for the treatment of dye bearing effluents which are usually alkaline, hot and saline. Copyright (c) 2010 Elsevier B.V. All rights reserved.

In-Vitro Analysis of the Effect of Constructional Parameters and Dye Class on the UV Protection Property of Cotton Knitted Fabrics.

PubMed

Kan, Chi-Wai; Au, Chui-Ha

2015-01-01

Cotton knitted fabrics were manufactured with different yarn types (conventional ring spun yarn and torque-free ring spun yarn) with different fibre types (combed cotton and combed Supima cotton) and yarn fineness (Ne30 and Ne40). These fabrics were then dyed with three types of dye (reactive, direct and sulphur dye) with three dye concentrations (0.1%, 1.0% and 5.0% on-weight of fabric (owf)) in three colours (red, yellow and blue). This study examined the impact of constructional parameters and dyeing on ultraviolet (UV) protection properties of cotton knitted fabric. In-vitro test with spectrophotometer was used for evaluating the UV protection property of dyed cotton knitted fabrics. Among the six parameters investigated, fineness of yarn and dye concentration were the most significant factors affecting UPF while the color effect is the least significant. Experimental results revealed that the UPF value of dyed fabrics made from combed cotton is generally higher than the combed Supima cotton since combed cotton is composed of shorter fibres which facilitate the blocking or absorption of UV radiation. Second, fabrics made with twist yarn (i.e. ring spun yarn) have higher UPF value than the corresponding ESTex one (i.e. torque-free yarn) in general since fabrics made with ring spun yarn tend to shrink during wet processing and so it is more compact. Third, the UPF value of fabrics made with 30Ne yarn was higher than the 40Ne one since it is thicker and has lower fabric porosity. Fourth, fabrics dyed with lower concentration of dye gave the lowest UPF. Fifth, the sulphur dyed samples performed worse than the reactive and direct dyed samples in terms of UV protection property. Sixth, there is no significant difference in UPF for red, yellow and blue coloured fabrics. Seventh, this study also demonstrated that lightness of fabric is negatively related to UV protection property.

In-Vitro Analysis of the Effect of Constructional Parameters and Dye Class on the UV Protection Property of Cotton Knitted Fabrics

PubMed Central

2015-01-01

Cotton knitted fabrics were manufactured with different yarn types (conventional ring spun yarn and torque-free ring spun yarn) with different fibre types (combed cotton and combed Supima cotton) and yarn fineness (Ne30 and Ne40). These fabrics were then dyed with three types of dye (reactive, direct and sulphur dye) with three dye concentrations (0.1%, 1.0% and 5.0% on-weight of fabric (owf)) in three colours (red, yellow and blue). This study examined the impact of constructional parameters and dyeing on ultraviolet (UV) protection properties of cotton knitted fabric. In-vitro test with spectrophotometer was used for evaluating the UV protection property of dyed cotton knitted fabrics. Among the six parameters investigated, fineness of yarn and dye concentration were the most significant factors affecting UPF while the color effect is the least significant. Experimental results revealed that the UPF value of dyed fabrics made from combed cotton is generally higher than the combed Supima cotton since combed cotton is composed of shorter fibres which facilitate the blocking or absorption of UV radiation. Second, fabrics made with twist yarn (i.e. ring spun yarn) have higher UPF value than the corresponding ESTex one (i.e. torque-free yarn) in general since fabrics made with ring spun yarn tend to shrink during wet processing and so it is more compact. Third, the UPF value of fabrics made with 30Ne yarn was higher than the 40Ne one since it is thicker and has lower fabric porosity. Fourth, fabrics dyed with lower concentration of dye gave the lowest UPF. Fifth, the sulphur dyed samples performed worse than the reactive and direct dyed samples in terms of UV protection property. Sixth, there is no significant difference in UPF for red, yellow and blue coloured fabrics. Seventh, this study also demonstrated that lightness of fabric is negatively related to UV protection property. PMID:26222792

Exploring function activated chlorins using MCD spectroscopy and DFT methods: design of a chlorin with a remarkably intense, red Q band.

PubMed

Zhang, Angel; Stillman, Martin J

2018-05-09

The electronic structures of three previously synthesized Ni-coordinated chlorins with β-substituents of thioketone, fluorene, and ketone were investigated using magnetic circular dichroism spectroscopy (MCD) and density functional theory (DFT) for potential application as sensitizers for dye-sensitized solar cells (DSSCs). Computational studies on modeled Zn-coordinated chlorins allowed identification of charge transfer and d-d transitions of the Ni2+ coordinated chlorins. Two fictive Zn chlorins, M1 and M2, were designed with thiophene units based on the fluorene substituted chlorin. Substitution with thiophene altered the typical arrangement of the four Gouterman molecular orbitals (MOs) and red-shifted and greatly intensified the lowest energy absorption band (the Q band). The introduction of the thiophene-based MO as the LUMO below the usual Gouterman LUMO is predicted to increase the efficiency of electron transfer from the dye to the conduction band of the semiconductor in DSSCs. The addition of a donor group on the opposite pyrrole (M2) red-shifted the Q band further and introduced a donor-based MO between the typical Gouterman HOMO and HOMO-1. Despite the relatively small ΔHOMO, M1 and M2 exhibited remarkably intense Q bands. M2 would be a possible candidate for application in DSSCs due to its panchromatic absorption, intense and red-shifted Q band, and the presence of the substituent based MO properties. Another indicator of a successful dye is the alignment of the ground state and excited state oxidation potentials (GSOP and ESOP, respectively) with respect to the conduction band of the semiconductor. The GSOP for M2 lies 0.55 eV below the I-/I3- redox potential and the ESOP lies 0.48 eV above the TiO2 conduction band. The impact of the thiophene dominance in the LUMO also supports the prediction of efficient sensitization properties. The remarkably intense Q band of M2 predicted to be at 777 nm with a ΔHOMO of just 1.04 eV provides a synthetic route to tetrapyrroles with extremely intense, red Q bands without the need for aza nitrogens of the phthalocyanines. This study illustrates the value of guided synthesis using MCD spectral analysis and computational methods for optimizing the design of porphyrin dyes.

Carbazole-based BODIPYs with ethynyl substituents at the boron center: solid-state excimer fluorescence in the VIS/NIR region.

PubMed

Maeda, Chihiro; Nagahata, Keiji; Ema, Tadashi

2017-09-26

Carbazole-based BODIPYs 1-6 with several different substituents at the boron atom site were synthesized. These dyes fluoresced in the solid state, and 3a with phenylethynyl groups exhibited a red-shifted and broad fluorescence spectrum, which suggested an excimer emission. Its derivatives 3b-n were synthesized, and the relationship between the solid-state emission and crystal packing was investigated. The X-ray crystal structures revealed cofacial dimers that might form excimers. From the structural optimization results, we found that the introduction of mesityl groups hindered intermolecular access and led to reduced interactions between the dimers. In addition, the red-shifted excimer fluorescence suppressed self-absorption, and dyes with ethynyl groups showed solid-state fluorescence in the vis/NIR region.

Degradation kinetics of organic dyes in water by high voltage atmospheric air and modified air cold plasma.

PubMed

Pankaj, S K; Wan, Zifan; Colonna, William; Keener, Kevin M

2017-07-01

High voltage atmospheric cold plasma (HVACP) is a novel, non-thermal technology which has shown potential for degradation of various toxic components in wastewater. In this study, HVACP was used to examine the degradation kinetics of methyl red, crystal violet and fast green FCF dyes. HVACP discharge was found to be a source of reactive nitrogen and oxygen species. High voltage application completely degraded all dyes tested in less than 5 min treatment time. Plasma from modified gas (∼65% O 2 ) further reduced the treatment time by 50% vs. plasma from dry air. First order and Weibull models were fitted to the degradation data. The Weibull model was found better in explaining the degradation kinetics of all the treated dyes.

Tricolor White-Light-Emitting Carbon Dots with Multiple-Cores@Shell Structure for WLED Application.

PubMed

Zhang, Tianyi; Zhao, Feifei; Li, Li; Qi, Bin; Zhu, Dongxia; Lü, Jianhua; Lü, Changli

2018-06-13

The past few years have witnessed the rapid development of carbon dots (CDs) due to their outstanding optical properties and a wide range of applications. However, the design and control of CDs with long-wavelength multicolor emission are still huge challenges to be addressed for their practical use in different fields. Here, novel nitrogen-doped multiple-core@shell-structured AC-CDs with tricolor emissions of red, green, and blue were constructed via one-pot hydrothermal method from 5-amino-1,10-phenanthroline and citric acid as reactants and the growth process of AC-CDs was monitored with the reaction time in the synthetic system. The origin of different fluorescence emissions was explored using the unique coordination ability of the surface groups of AC-CDs. An obvious concentration dependence of fluorescent properties was observed for the as-prepared AC-CDs, and a highly fluorescent quantum yield (QY) of 67% for red emission at 630 nm can be obtained by adjusting concentration of AC-CDs. The pure white-light emission (0.33, 0.33; Commission Internationale de l'Elcairage coordinate) was carried out from single carbon dot with QY of 29% through regulation of the excitation and concentration of multiple-core@shell-structured AC-CDs. In addition, because of their excellent photoluminescent properties, the white-emitting AC-CDs as emitting phosphor can be easily used in the fabrication of white-light-emitting diode with good anti-photobleaching and temperature stability.

Characterization of the electro-optic effect in styrylpyridinium cyanine dye thin-film crystals by an ac modulation method

NASA Astrophysics Data System (ADS)

Yoshimura, Tetsuzo

1987-09-01

The electro-optic effect in styrylpyridinium cyanine dye (SPCD) thin-film crystals is characterized by a newly developed ac modulation method that is effective in characterizing thin-film materials of small area. SPCD thin-film crystals 3-10 μm thick were grown from a methanol solution of SPCD. The crystal shows strong dichroism and anisotropy of refractive index, indicating that molecular dipole moments align along a definite direction (z axis). When an electric field is applied along the z axis, SPCD thin-film crystals show a large figure of merit of electro-optic phase retardation of 6.5×10-10 m/V, which is 5 times as large as in LiNbO3 crystal, 2 times that in 2-methyl-4-nitroaniline (MNA) crystal, and is the largest ever reported in organic solids. The electro-optic coefficient r33 of SPCD crystals is estimated to be approximately 4.3×10-10 m/V, which is 6 times larger than that of an MNA crystal. This value is consistent with that expected from second-harmonic generation measurements.

Determination of sudan dyes in red wine and fruit juice using ionic liquid-based liquid-liquid microextraction and high-performance liquid chromatography.

PubMed

Sun, Shuo; Wang, Ying; Yu, Wenzhi; Zhao, Tianqi; Gao, Shiqian; Kang, Mingqin; Zhang, Yupu; Zhang, Hanqi; Yu, Yong

2011-07-01

The liquid-liquid microextraction (LLME) was developed for extracting sudan dyes from red wine and fruit juice. Room temperature ionic liquid was used as the extraction solvent. The target analytes were determined by high-performance liquid chromatography. The extraction parameters were optimized. The optimal conditions are as follows: volume of [C(6)MIM][PF(6)] 50 μL; the extraction time 10 min; pH value of the sample solution 7.0; NaCl concentration in sample solution 5%. The extraction recoveries for the analytes in red wine and fruit samples are 86.79-108.28 and 68.54-85.66%, whereas RSDs are 1.42-5.12 and 1.43-6.19%, respectively. The limits of detection and quantification were 0.428 and 1.426 ng/mL for sudan I, 0.938 and 3.127 ng/mL for sudan II, 1.334 and 4.445 ng/mL for sudan III, 1.454 and 4.846 ng/mL for sudan IV, respectively. Compared with conventional liquid-liquid extraction (CLLE) and ultrasonic extraction (UE), when LLME was applied, the sample amount was less (LLME: 4 mL; CLLE: 10 mL; UE: 10 mL), the extraction time was shorter (LLME: 15 min; CLLE: 110 min; UE: 50 min) and the extraction solvent amount was less (LLME: 0.05 mL IL; CLLE: 15 mL hexane; UE: 20 mL hexane). The proposed method offers a simple, rapid and efficient sample preparation for determining sudan dyes in red wine and fruit juice samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Masked rhodamine dyes of five principal colors revealed by photolysis of a 2-diazo-1-indanone caging group: synthesis, photophysics, and light microscopy applications.

PubMed

Belov, Vladimir N; Mitronova, Gyuzel Yu; Bossi, Mariano L; Boyarskiy, Vadim P; Hebisch, Elke; Geisler, Claudia; Kolmakov, Kirill; Wurm, Christian A; Willig, Katrin I; Hell, Stefan W

2014-10-06

Caged rhodamine dyes (Rhodamines NN) of five basic colors were synthesized and used as "hidden" markers in subdiffractional and conventional light microscopy. These masked fluorophores with a 2-diazo-1-indanone group can be irreversibly photoactivated, either by irradiation with UV- or violet light (one-photon process), or by exposure to intense red light (λ∼750 nm; two-photon mode). All dyes possess a very small 2-diazoketone caging group incorporated into the 2-diazo-1-indanone residue with a quaternary carbon atom (C-3) and a spiro-9H-xanthene fragment. Initially they are non-colored (pale yellow), non-fluorescent, and absorb at λ=330-350 nm (molar extinction coefficient (ε)≈10(4)  M(-1)  cm(-1)) with a band edge that extends to about λ=440 nm. The absorption and emission bands of the uncaged derivatives are tunable over a wide range (λ=511-633 and 525-653 nm, respectively). The unmasked dyes are highly colored and fluorescent (ε=3-8×10(4)  M(-1)  cm(-1) and fluorescence quantum yields (ϕ)=40-85% in the unbound state and in methanol). By stepwise and orthogonal protection of carboxylic and sulfonic acid groups a highly water-soluble caged red-emitting dye with two sulfonic acid residues was prepared. Rhodamines NN were decorated with amino-reactive N-hydroxysuccinimidyl ester groups, applied in aqueous buffers, easily conjugated with proteins, and readily photoactivated (uncaged) with λ=375-420 nm light or intense red light (λ=775 nm). Protein conjugates with optimal degrees of labeling (3-6) were prepared and uncaged with λ=405 nm light in aqueous buffer solutions (ϕ=20-38%). The photochemical cleavage of the masking group generates only molecular nitrogen. Some 10-40% of the non-fluorescent (dark) byproducts are also formed. However, they have low absorbance and do not quench the fluorescence of the uncaged dyes. Photoactivation of the individual molecules of Rhodamines NN (e.g., due to reversible or irreversible transition to a "dark" non-emitting state or photobleaching) provides multicolor images with subdiffractional optical resolution. The applicability of these novel caged fluorophores in super-resolution optical microscopy is exemplified. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Early red spruce restoration research by the Appalachian Forest Experiment Station, 1922-1954

Treesearch

James S. Rentch; Thomas M. Schuler

2017-01-01

This photograph (Fig. 1), taken in June of 1923 by E.S. Ship, depicts a red spruce (Picea rubens) stand with advanced reproduction near the summit of Mount Mitchell in the Pisgah National Forest of North Carolina. According to Hopkins (1899), the original extent of red spruce encompassed as much as 1,500,000 ac in the southern Appalachians; by 1895...

The chemical bonds effect of anthocyanin and chlorophyll dyes on TiO2 for dye-sensitized solar cell (DSSC)

NASA Astrophysics Data System (ADS)

Ahliha, A. H.; Nurosyid, F.; Supriyanto, A.; Kusumaningsih, T.

2017-11-01

Anthocyanin and chlorophyll dyes have been blended as the photosensitizer of Dye-Sensitized Solar Cell (DSSC). The results study showed the effect of chemical bond dyes on TiO2 and the efficiency of DSSC. Ratio blend of the anthocyanin and chlorophyll dyes are 1:1. The absorbance of dyes and TiO2 were characterized using UV-Vis Spectrophotometer. The chemical bonds contained in TiO2-dyes were characterized using FT-IR spectrophotometer. The efficiency of DSSC was calculated using I-V meter. The absorption spectra of chlorophyll: anthocyanin blend dye solutions and TiO2 films can increase after the dye adsorption. Absorbance characterization of anthocyanin and chlorophyll dye blend solutions showed three peaks at the wavelength of 412 nm; 535.5 nm; and 656.5 nm. Absorbance characterization of spinach before being blend with anthocyanin dyes solutions showed two peaks at the wavelength of 431 nm and 665.5 nm. The absorption spectra of TiO2 films can increase after the dyes adsorption at the wavelength of 400 nm. FT-IR spectra of TiO2 founded the functional groups C-Br, C=C, and O-H. The functional groups founded in anthocyanin: chlorophyll dye blended on the surface of TiO2 are C-Br, C-O, O-H, C-H, C=C, C=O, and O-H. The result showed that the greatest efficiency of 0.0544% at dye red cabbage-spinach. Adsorption blends of anthocyanin and chlorophyll dyes on the surface of TiO2 can be used as the photosensitizer for DSSC.

The impact of cell culture equipment on energy loss.

PubMed

Davies, Lleucu B; Kiernan, Michael N; Bishop, Joanna C; Thornton, Catherine A; Morgan, Gareth

2014-01-01

Light energy of discrete wavelengths supplied via lasers and broadband intense pulsed light have been used therapeutically for many years. In vitro models complement clinical studies, especially for the elucidation of underlying mechanisms of action. Clarification that light energy reaches the cells is necessary when developing protocols for the treatment of cells using in vitro models. Few studies report on energy loss in cell culture equipment. The ability of energy from light with therapeutic potential to reach cells in culture needs to be determined; this includes determining the proportion of light energy lost within standard cell culture media and cell culture vessels. The energy absorption of cell culture media, with/without the pH indicator dye phenol red, and the loss of energy within different plastics and glassware used typically for in vitro cell culture were investigated using intense pulsed light and a yellow pulsed dye laser. Media containing phenol red have a distinctive absorption peak (560 nm) absent in phenol red-free media and restored by the addition of phenol red. For both light sources, energy loss was lowest in standard polystyrene tissue culture flasks or multi-well plates and highest in polypropylene vessels or glass tubes. The effects of phenol red-free media on the absorption of energy varied with the light source used. Phenol red-free media are the media of choice; polystyrene vessels with flat surfaces such as culture flasks or multi-well plates should be used in preference to polypropylene or glass vessels.

Sensitising potential of four textile dyes and some of their metabolites in a modified local lymph node assay.

PubMed

Stahlmann, Ralf; Wegner, Matthias; Riecke, Kai; Kruse, Matthias; Platzek, Thomas

2006-02-15

We studied the sensitising and allergenic potentials of the textile dyes disperse yellow 3, disperse orange 30, disperse red 82, disperse yellow 211 and two metabolites of disperse yellow 3, 4-aminoacetanilide and 2-amino-p-cresol, using modified protocols of the murine "local lymph node assay" (LLNA). Test substances were applied either to the dorsum of the mice ears (sensitisation protocol) or they were first applied to the skin of their backs and 2 weeks later to their ears (sensitisation-challenge protocol). In addition to the endpoints weight and cell number of the draining ear lymph nodes we analysed lymphocyte subpopulations by flow cytometry. In the sensitisation protocol, disperse yellow 3 and its metabolite 4-aminoacetanilide did not induce significant effects, whereas in the sensitisation-challenge protocol cell number and lymph node weight increased significantly indicating a sensitising potential in NMRI mice. Hence, two-phase treatment (skin of the back, ear) increased the sensitivity of this assay. The second metabolite of disperse yellow 3, 2-amino-p-cresol, showed distinct effects in both treatment protocols; this applied mainly to the parameters cell number and lymph node weight. The dye disperse red 82 caused ambiguous increases in lymph node weight and cell number in the sensitisation protocol which were not reproduced in the sensitisation-challenge protocol, ruling out a relevant sensitising potential for this dye in NMRI mice. Disperse yellow 211 and disperse orange 30 did not induce relevant changes under our experimental conditions. Phenotyping of lymphocytes did not influence the assessment of these dyes.

Pulsed dye laser treatment of rosacea using a novel 15 mm diameter treatment beam.

PubMed

Bernstein, Eric F; Schomacker, Kevin; Paranjape, Amit; Jones, Christopher J

2018-04-10

The pulsed-dye laser has been used to treat facial redness and rosacea for decades. Recent advances in dye laser technology enable 50% higher output energies supporting 50% larger treatment areas, and beam-diameters up to 15 mm with clinically-relevant fluences. In this study, we investigate this novel pulsed-dye laser using a 15 mm diameter beam for treatment of rosacea. Twenty subjects with erythemato-telangiectatic rosacea were enrolled in the study. A total of 4 monthly treatments were administered, first treating linear vessels with a 3 × 10 mm elliptical beam, then diffuse redness with a 15-mm diameter circular beam. Blinded assessment of digital, cross-polarized photographs taken 2 months following the last treatment was performed using an 11-point clearance scale. Nineteen subjects completed the study. Blinded reviewers correctly identified baseline photos in 55 out of the total of 57 images (96.5%). The blinded reviewers scored 17 of the 19 subjects with an improvement greater than 40%, and 11 of the 19 subjects greater than 50%. The average improvement was 53.9%. Side effects were limited to mild edema, mild to moderate erythema, and mild to moderate bruising. This study demonstrates that a newly designed pulsed-dye laser having a novel 15-mm diameter treatment beam improves the appearance of rosacea with a favorable safety profile. Lasers Surg. Med. 9999:1-5, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

A hybrid artificial neural network and particle swarm optimization for prediction of removal of hazardous dye brilliant green from aqueous solution using zinc sulfide nanoparticle loaded on activated carbon.

PubMed

Ghaedi, M; Ansari, A; Bahari, F; Ghaedi, A M; Vafaei, A

2015-02-25

In the present study, zinc sulfide nanoparticle loaded on activated carbon (ZnS-NP-AC) simply was synthesized in the presence of ultrasound and characterized using different techniques such as SEM and BET analysis. Then, this material was used for brilliant green (BG) removal. To dependency of BG removal percentage toward various parameters including pH, adsorbent dosage, initial dye concentration and contact time were examined and optimized. The mechanism and rate of adsorption was ascertained by analyzing experimental data at various time to conventional kinetic models such as pseudo-first-order and second order, Elovich and intra-particle diffusion models. Comparison according to general criterion such as relative error in adsorption capacity and correlation coefficient confirm the usability of pseudo-second-order kinetic model for explanation of data. The Langmuir models is efficiently can explained the behavior of adsorption system to give full information about interaction of BG with ZnS-NP-AC. A multiple linear regression (MLR) and a hybrid of artificial neural network and partial swarm optimization (ANN-PSO) model were used for prediction of brilliant green adsorption onto ZnS-NP-AC. Comparison of the results obtained using offered models confirm higher ability of ANN model compare to the MLR model for prediction of BG adsorption onto ZnS-NP-AC. Using the optimal ANN-PSO model the coefficient of determination (R(2)) were 0.9610 and 0.9506; mean squared error (MSE) values were 0.0020 and 0.0022 for the training and testing data set, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

A hybrid artificial neural network and particle swarm optimization for prediction of removal of hazardous dye brilliant green from aqueous solution using zinc sulfide nanoparticle loaded on activated carbon

NASA Astrophysics Data System (ADS)

Ghaedi, M.; Ansari, A.; Bahari, F.; Ghaedi, A. M.; Vafaei, A.

2015-02-01

In the present study, zinc sulfide nanoparticle loaded on activated carbon (ZnS-NP-AC) simply was synthesized in the presence of ultrasound and characterized using different techniques such as SEM and BET analysis. Then, this material was used for brilliant green (BG) removal. To dependency of BG removal percentage toward various parameters including pH, adsorbent dosage, initial dye concentration and contact time were examined and optimized. The mechanism and rate of adsorption was ascertained by analyzing experimental data at various time to conventional kinetic models such as pseudo-first-order and second order, Elovich and intra-particle diffusion models. Comparison according to general criterion such as relative error in adsorption capacity and correlation coefficient confirm the usability of pseudo-second-order kinetic model for explanation of data. The Langmuir models is efficiently can explained the behavior of adsorption system to give full information about interaction of BG with ZnS-NP-AC. A multiple linear regression (MLR) and a hybrid of artificial neural network and partial swarm optimization (ANN-PSO) model were used for prediction of brilliant green adsorption onto ZnS-NP-AC. Comparison of the results obtained using offered models confirm higher ability of ANN model compare to the MLR model for prediction of BG adsorption onto ZnS-NP-AC. Using the optimal ANN-PSO model the coefficient of determination (R2) were 0.9610 and 0.9506; mean squared error (MSE) values were 0.0020 and 0.0022 for the training and testing data set, respectively.

Biosorption of synthetic dyes (Direct Red 89 and Reactive Green 12) as an ecological refining step in textile effluent treatment.

PubMed

Guendouz, Samira; Khellaf, Nabila; Zerdaoui, Mostefa; Ouchefoun, Moussa

2013-06-01

With the use of cost-effective natural materials, biosorption is considered as an ecological tool that is applied worldwide for the remediation of pollution. In this study, we proposed Lemna gibba biomass (LGB), a lignocellulosic sorbent material, for the removal of two textile dyes, Direct Red 89 (DR-89) and Reactive Green 12 (RG-12). These azo dyes commonly used in dying operations of natural and synthetic fibres are the most important pollutants produced in textile industry effluents. For this purpose, batch biosorption experiments were carried out to assess the efficacy of LGB on dye treatment by evaluating the effect of contact time, biomass dosage, and initial dye concentration. The results indicated that the bioremoval efficiency of 5 mg L(-1) DR-89 and RG-12 reached approximately 100 % after 20 min of the exposure time; however, the maximum biosorption of 50 mg L(-1) DR-89 and 15 mg L(-1) RG-12 was determined to be about 60 and 47 %, respectively. Fourier transform infrared spectroscopy used to explain the sorption mechanism showed that the functional groups of carboxylic acid and hydroxyl played a major role in the retention of these pollutants on the biomass surface. The modelling results using Freundlich, Langmuir, Temkin, Elovich, and Dubini Radushkevich (D-R) isotherms demonstrated that the DR-89 biosorption process was better described with the Langmuir theory (R (2) =0.992) while the RG-12 biosorption process fitted well by the D-R isotherm equation (R (2) =0.988). The maximum biosorption capacity was found to be 20.0 and 115.5 mg g(-1) for DR-89 and RG-12, respectively, showing a higher ability of duckweed biomass for the bioremoval of the green dye. The thermodynamic study showed that the dye biosorption was a spontaneous and endothermic process. The efficacy of using duckweed biomass for the bioremoval of the two dyes was limited to concentrations ≤50 mg L(-1), indicating that L. gibba biomass may be suitable in the refining step of textile effluent treatment.

Titania modified activated carbon prepared from sugarcane bagasse: adsorption and photocatalytic degradation of methylene blue under visible light irradiation.

PubMed

El-Salamony, R A; Amdeha, E; Ghoneim, S A; Badawy, N A; Salem, K M; Al-Sabagh, A M

2017-12-01

Activated carbon (AC), prepared from sugarcane bagasse waste through a low-temperature chemical carbonization treatment, was used as a support for nano-TiO 2 . TiO 2 supported on AC (xTiO 2 -AC) catalysts (x = 10, 20, 50, and 70 wt.%) were prepared through a mechano-mixing method. The photocatalysts were characterized by Raman, X-ray diffraction analysis, FTIR, S BET , field emission scanning electron microscope, and optical technique. The adsorption and photo-activity of the prepared catalysts (xTiO 2 -AC) were evaluated using methylene blue (MB) dye. The photocatalytic degradation of MB was evaluated under UVC irradiation and visible light. The degradation percentage of the 100 ppm MB at neutral pH using 20TiO 2 -AC reaches 96 and 91 after 180 min under visible light and UV irradiation, respectively. In other words, these catalysts are more active under visible light than under UV light irradiation, opening the possibility of using solar light for this application.

Phenol red-silk tyrosine cross-linked hydrogels.

PubMed

Sundarakrishnan, Aswin; Herrero Acero, Enrique; Coburn, Jeannine; Chwalek, Karolina; Partlow, Benjamin; Kaplan, David L

2016-09-15

Phenol red is a cytocompatible pH sensing dye that is commonly added to cell culture media, but removed from some media formulations due to its structural mimicry of estrogen. Phenol red free media is also used during live cell imaging, to avoid absorbance and fluorescence quenching of fluorophores. To overcome these complications, we developed cytocompatible and degradable phenol red-silk tyrosine cross-linked hydrogels using horseradish peroxidase (HRP) enzyme and hydrogen peroxide (H2O2). Phenol red added to silk during tyrosine crosslinking accelerated di-tyrosine formation in a concentration-dependent reaction. Phenol red diffusion studies and UV-Vis spectra of phenol red-silk tyrosine hydrogels at different pHs showed altered absorption bands, confirming entrapment of dye within the hydrogel network. LC-MS of HRP-reacted phenol red and N-acetyl-l-tyrosine reaction products confirmed covalent bonds between the phenolic hydroxyl group of phenol red and tyrosine on the silk. At lower phenol red concentrations, leak-proof hydrogels which did not release phenol red were fabricated and found to be cytocompatible based on live-dead staining and alamar blue assessments of encapsulated fibroblasts. Due to the spectral overlap between phenol red absorbance at 415nm and di-tyrosine fluorescence at 417nm, phenol red-silk hydrogels provide both absorbance and fluorescence-based pH sensing. With an average pKa of 6.8 and good cytocompatibiltiy, phenol red-silk hydrogels are useful for pH sensing in phenol red free systems, cellular microenvironments and bioreactors. Phenol red entrapped within hydrogels facilitates pH sensing in phenol red free environments. Leak-proof phenol red based pH sensors require covalent binding techniques, but are complicated due to the lack of amino or carboxyl groups on phenol red. Currently, there is no simple, reliable technique to covalently link phenol red to hydrogel matrices, for real-time pH sensing in cell culture environments. Herein, we take advantage of phenolic groups for covalent linkage of phenol red to silk tyrosine in the presence of HRP and H2O2. The novelty of the current system stems from its simplicity and the use of silk protein to create a cytocompatible, degradable sensor capable of real-time pH sensing in cell culture microenvironments. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

In vitro mutagenicity, NMR metabolite characterization of azo and triphenylmethanes dyes by adherents bacteria and the role of the "cna" adhesion gene in activated sludge.

PubMed

Ayed, Lamia; Bakir, Karima; Ben Mansour, Hedi; Hammami, Saousen; Cheref, Abdelkrim; Bakhrouf, Amina

2017-02-01

Staphylococcus aureus, showing the greatest decolorization ability, was further investigated for Methyl Red (MR) Congo Red (CR), Crystal Violet (CV) and Malachite Green (MG) decolorization using response surface methodology (RSM). The chemometric methods use, based on statistical design of experiments (DOEs) such as RSM is becoming increasingly widespread in several sciences such as analytical chemistry, engineering and environmental chemistry. Stapphylococcus aureus ATCC 25923, Stapphylococcus aureus (S1) and Stapphylococcus aureus (S2), were isolated from textile wastewater plant located in KsarHellal, Tunisia and were tested for their decolorization capacity. PCR technique was utilized to identify the 3 bacterial strains and to detect the adhesin gene "cna". Biodegradation of MR, CR, CV and MG (750 ppm), were investigated under shaking condition in Mineral Salt Medium (MSM) solution at pH 7.5 and temperature 30 °C, using a 3.7 × 10 5  CFU/ml as inoculum size. Our results showed that Staphylococcus aureus had a high decolorization capacity. Nuclear magnetic resonance (NMR) spectroscopy analysis confirmed the biodegradation of dyes. The four dyes mutagenicity with the S9 metabolizing system decreased significantly after biodegradation and totally disappeared. Nuclear magnetic resonance (NMR) spectroscopy analysis confirmed the biodegradation of dyes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of a combined process of moving-bed biofilm reactor (MBBR) and chemical coagulation for dyeing wastewater treatment.

PubMed

Shin, D H; Shin, W S; Kim, Y H; Han, Myung Ho; Choi, S J

2006-01-01

A combined process consisted of a Moving-Bed Biofilm Reactor (MBBR) and chemical coagulation was investigated for textile wastewater treatment. The pilot scale MBBR system is composed of three MBBRs (anaerobic, aerobic-1 and aerobic-2 in series), each reactor was filled with 20% (v/v) of polyurethane-activated carbon (PU-AC) carrier for biological treatment followed by chemical coagulation with FeCl2. ln the MBBR process, 85% of COD and 70% of color (influent COD = 807.5 mg/L and color = 3,400 PtCo unit) were removed using relatively low MLSS concentration and short hydraulic retention time (HRT = 44 hr). The biologically treated dyeing wastewater was subjected to chemical coagulation. After coagulation with FeCl2, 95% of COD and 97% of color were removed overall. The combined process of MBBR and chemical coagulation has promising potential for dyeing wastewater treatment.

Self-Assembly of Cis-Configured Squaraine Dyes at the TiO2-Dye Interface: Far-Red Active Dyes for Dye-Sensitized Solar Cells.

PubMed

Punitharasu, Vellimalai; Mele Kavungathodi, Munavvar Fairoos; Nithyanandhan, Jayaraj

2018-05-16

To synergize both steric and electronic factors in designing the dyes for dye-sensitized solar cells, a series of cis-configured unsymmetrical squaraine dyes P11-P15 with suitably functionalized alkyl groups and squaric acid units containing the electron-withdrawing groups were synthesized, respectively. These dyes capture the importance of (i) the effect and position of branched alkyl groups, (ii) mono- and di-anchoring groups containing dyes, and (iii) further appending the alkyl groups through the cyanoester vinyl unit on the central squaric acid units of D-A-D-based cis-configured squaraine dyes. All the above factors govern the controlled self-assembly of the dyes on the TiO 2 surface which helps to broaden the absorption profile of the dyes with an increased energy-harvesting process. With respect to the position of the branched alkyl groups, dye P11 with the sp 3 -C and N-alkyl groups away from the TiO 2 surface showed a better device efficiency of 5.98% ( J sc of 14.46 mA cm -2 , V oc of 0.576 V, and ff of 71.8%) than its positional isomer P12 with 3.45% ( J sc of 8.78 mA cm -2 , V oc of 0.554 V, and ff of 70.9%). However, with respect to the dyes containing mono- and di-anchoring groups, P13 with two anchoring units exhibited a superior device performance of 7.58% ( J sc of 17.12 mA cm -2 , V oc of 0.618 V, and ff of 71.7%) in the presence of optically transparent co-adsorbent CDCA (3α,7α-dihydroxy-5β-cholanic acid) than dyes P11 and P12.

Light responses and morphology of bNOS-immunoreactive neurons in the mouse retina

PubMed Central

Pang, Ji-Jie; Gao, Fan; Wu, Samuel M.

2010-01-01

Nitric oxide (NO), produced by NO synthase (NOS), modulates the function of all retinal neurons and ocular blood vessels and participates in the pathogenesis of ocular diseases. To further understand the regulation of ocular NO release, we systematically studied the morphology, topography and light responses of NOS-containing amacrine cells (NOACs) in dark-adapted mouse retina. Immunohistological staining for neuronal NOS (bNOS), combined with retrograde labeling of ganglion cells (GCs) with Neurobiotin (NB, a gap junction permeable dye) and Lucifer yellow (LY, a less permeable dye), was used to identify NOACs. The light responses of ACs were recorded under whole-cell voltage clamp conditions and cell morphology was examined with a confocal microscope. We found that in dark-adapted conditions bNOS-immunoreactivity (IR) was present primarily in the inner nuclear layer and the ganglion cell layer. bNOS-IR somas were negative for LY, thus they were identified as ACs; nearly 6 % of the cells were labeled by NB but not by LY, indicating that they were dye-coupled with GCs. Three morphological subtypes of NOACs (NI, NII and displaced) were identified. The cell density, inter-cellular distance and the distribution of NOACs were studied in whole retinas. Light evoked depolarizing highly sensitive ON-OFF responses in NI cells and less sensitive OFF responses in NII cells. Frequent (1 to 2 Hz) or abrupt change of light-intensity evoked larger peak responses. The possibility for light to modify NO release from NOACs is discussed. PMID:20503422

Brown seaweed pigment as a dye source for photoelectrochemical solar cells

NASA Astrophysics Data System (ADS)

Calogero, Giuseppe; Citro, Ilaria; Di Marco, Gaetano; Armeli Minicante, Simona; Morabito, Marina; Genovese, Giuseppa

2014-01-01

Chlorophylls based-dyes obtained from seaweeds represent attractive alternatives to the expensive and polluting pyridil based Ru complexes because of their abundance in nature. Another important characteristic is that the algae do not subtract either cropland or agricultural water, therefore do not conflict with agro-food sector. This pigment shows a typical intense absorption in the UV/blue (Soret band) and a less intense band in the red/near IR (Q band) spectral regions and for these reasons appear very promising as sensitizer dyes for DSSC. In the present study, we utilized chlorophylls from samples of the brown alga Undaria pinnatifida as sensitizer in DSSCs. The dye, extracted by frozen seaweeds and used without any chemical purification, showed a very good fill factor (0.69). Even the photelectrochemical parameters if compared with the existent literature are very interesting.

Economics of Red Pine Management for Utility Pole Timber

Treesearch

Gerald H. Grossman; Karen Potter-Witter

1991-01-01

Including utility poles in red pine management regimes leads to distinctly different management recommendations. Where utility pole markets exist, managing for poles will maximize net returns. To do so, plantations should be maintained above 110 ft2/ac, higher than usually recommended. In Michigan's northern lower peninsula, approximately...

RELIC: a novel dye-bias correction method for Illumina Methylation BeadChip.

PubMed

Xu, Zongli; Langie, Sabine A S; De Boever, Patrick; Taylor, Jack A; Niu, Liang

2017-01-03

The Illumina Infinium HumanMethylation450 BeadChip and its successor, Infinium MethylationEPIC BeadChip, have been extensively utilized in epigenome-wide association studies. Both arrays use two fluorescent dyes (Cy3-green/Cy5-red) to measure methylation level at CpG sites. However, performance difference between dyes can result in biased estimates of methylation levels. Here we describe a novel method, called REgression on Logarithm of Internal Control probes (RELIC) to correct for dye bias on whole array by utilizing the intensity values of paired internal control probes that monitor the two color channels. We evaluate the method in several datasets against other widely used dye-bias correction methods. Results on data quality improvement showed that RELIC correction statistically significantly outperforms alternative dye-bias correction methods. We incorporated the method into the R package ENmix, which is freely available from the Bioconductor website ( https://www.bioconductor.org/packages/release/bioc/html/ENmix.html ). RELIC is an efficient and robust method to correct for dye-bias in Illumina Methylation BeadChip data. It outperforms other alternative methods and conveniently implemented in R package ENmix to facilitate DNA methylation studies.

Durable electrooptic devices comprising ionic liquids

DOEpatents

Burrell, Anthony K [Los Alamos, NM; Agrawal, Anoop [Tucson, AZ; Cronin,; John, P [Tucson, AZ; Tonazzi, Juan C. L. [Tucson, AZ; Warner, Benjamin P [Los Alamos, NM; McCleskey, T Mark [Los Alamos, NM

2009-12-15

Electrolyte solutions for electrochromic devices such as rear view mirrors and displays with low leakage currents are prepared using inexpensive, low conductivity conductors. Preferred electrolytes include bifunctional redox dyes and molten salt solvents with enhanced stability toward ultraviolet radiation. The solvents include lithium or quaternary ammonium cations, and perfluorinated sulfonylimide anions selected from trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). Electroluminescent, electrochromic and photoelectrochromic devices with nanostructured electrodes include ionic liquids with bifunctional redox dyes. Some of the electrolyte solutions color to red when devices employing the solutions are powered, leading to red or neutral electrooptic devices.

Durable Electrooptic Devices Comprising Ionic Liquids

DOEpatents

Burrell, Anthony K.; Agrawal, Anoop; Cronin, John P.; Tonazzi, Juan C. L.; Warner, Benjamin P.; McCleskey, T. Mark

2008-11-11

Electrolyte solutions for electrochromic devices such as rear view mirrors and displays with low leakage currents are prepared using inexpensive, low conductivity conductors. Preferred electrolytes include bifunctional redox dyes and molten salt solvents with enhanced stability toward ultraviolet radiation. The solvents include lithium or quaternary ammonium cations, and perfluorinated sulfonylimide anions selected from trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). Electroluminescent, electrochromic and photoelectrochromic devices with nanostructured electrodes include ionic liquids with bifunctional redox dyes. Some of the electrolyte solutions color to red when devices employing the solutions are powered, leading to red or neutral electrooptic devices.

An efficient absorbing system for spectrophotometric determination of nitrogen dioxide

NASA Astrophysics Data System (ADS)

Kaveeshwar, Rachana; Amlathe, Sulbha; Gupta, V. K.

A simple and sensitive spectrophotometric method for determination of atmospheric nitrogen dioxide using o-nitroaniline as an efficient absorbing, as well as diazotizing, reagent is described. o-Nitroaniline present in the absorbing medium is diazotized by the absorbed nitrite ion to form diazonium compound. This is later coupled with 1-amino-2-naphthalene sulphonic acid (ANSA) in acidic medium to give red-violet-coloured dye,having λmax = 545 nm. The isoamyl extract of the red azo dye has λmax = 530 nm. The proposed reagents has ≈ 100% collection efficiency and the stoichiometric ratio of NO 2:NO 2- is 0.74. The other important analytical parameters have been investigated. By employing solvent extraction the sensitivity of the reaction was increased and up to 0.03 mg m -3 nitrogen dioxide could be estimated.

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets

PubMed Central

de Oliveira, Cibele Braga; Maia, Luiz Guilherme Martins; Santos-Pinto, Ary; Gandini Júnior, Luiz Gonzaga

2014-01-01

Objective The aim of this in vitro study was to analyze color stability of monocrystalline and polycrystalline ceramic brackets after immersion in dye solutions. Methods Seven ceramic brackets of four commercial brands were tested: Two monocrystalline and two polycrystalline. The brackets were immersed in four dye solutions (coffee, red wine, Coke and black tea) and in artificial saliva for the following times: 24 hours, 7, 14 and 21 days, respectively. Color changes were measured by a spectrophotometer. Data were assessed by Multivariate Profile Analysis, Analysis of Variance (ANOVA) and Multiple Comparison Tests of means. Results There was a perceptible change of color in all ceramic brackets immersed in coffee (ΔE* Allure = 7.61, Inspire Ice = 6.09, Radiance = 6.69, Transcend = 7.44), black tea (ΔE* Allure = 6.24, Inspire Ice = 5.21, Radiance = 6.51, Transcend = 6.14) and red wine (ΔE* Allure = 6.49, Inspire Ice = 4.76, Radiance = 5.19, Transcend = 5.64), but no change was noticed in Coke and artificial saliva (ΔE < 3.7). Conclusion Ceramic brackets undergo color change when exposed to solutions of coffee, black tea and red wine. However, the same crystalline structure, either monocrystalline or polycrystalline, do not follow the same or a similar pattern in color change, varying according to the bracket fabrication, which shows a lack of standardization in the manufacturing process. Coffee dye produced the most marked color changes after 21 days of immersion for most ceramic brackets evaluated. PMID:25279530

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets.

PubMed

de Oliveira, Cibele Braga; Maia, Luiz Guilherme Martins; Santos-Pinto, Ary; Gandini Junior, Luiz Gonzaga

2014-01-01

The aim of this in vitro study was to analyze color stability of monocrystalline and polycrystalline ceramic brackets after immersion in dye solutions. Seven ceramic brackets of four commercial brands were tested: Two monocrystalline and two polycrystalline. The brackets were immersed in four dye solutions (coffee, red wine, Coke and black tea) and in artificial saliva for the following times: 24 hours, 7, 14 and 21 days, respectively. Color changes were measured by a spectrophotometer. Data were assessed by Multivariate Profile Analysis, Analysis of Variance (ANOVA) and Multiple Comparison Tests of means. There was a perceptible change of color in all ceramic brackets immersed in coffee (ΔE* Allure = 7.61, Inspire Ice = 6.09, Radiance = 6.69, Transcend = 7.44), black tea (ΔE* Allure = 6.24, Inspire Ice = 5.21, Radiance = 6.51, Transcend = 6.14) and red wine (ΔE* Allure = 6.49, Inspire Ice = 4.76, Radiance = 5.19, Transcend = 5.64), but no change was noticed in Coke and artificial saliva (ΔE < 3.7). Ceramic brackets undergo color change when exposed to solutions of coffee, black tea and red wine. However, the same crystalline structure, either monocrystalline or polycrystalline, do not follow the same or a similar pattern in color change, varying according to the bracket fabrication, which shows a lack of standardization in the manufacturing process. Coffee dye produced the most marked color changes after 21 days of immersion for most ceramic brackets evaluated.

Influence of the amyloid dye Congo red on curli, cellulose, and the extracellular matrix in E. coli during growth and matrix purification.

PubMed

Reichhardt, Courtney; McCrate, Oscar A; Zhou, Xiaoxue; Lee, Jessica; Thongsomboon, Wiriya; Cegelski, Lynette

2016-11-01

Microbial biofilms are communities of cells characterized by a hallmark extracellular matrix (ECM) that confers functional attributes to the community, including enhanced cohesion, adherence to surfaces, and resistance to external stresses. Understanding the composition and properties of the biofilm ECM is crucial to understanding how it functions and protects cells. New methods to isolate and characterize ECM are emerging for different biofilm systems. Solid-state nuclear magnetic resonance was used to quantitatively track the isolation of the insoluble ECM from the uropathogenic Escherichia coli strain UTI89 and understand the role of Congo red in purification protocols. UTI89 assembles amyloid-integrated biofilms when grown on YESCA nutrient agar. The ECM contains curli amyloid fibers and a modified form of cellulose. Biofilms formed by UTI89 and other E. coli and Salmonella strains are often grown in the presence of Congo red to visually emphasize wrinkled agar morphologies and to score the production of ECM. Congo red is a hallmark amyloid-binding dye and binds to curli, yet also binds to cellulose. We found that growth in Congo red enabled more facile extraction of the ECM from UTI89 biofilms and facilitates isolation of cellulose from the curli mutant, UTI89ΔcsgA. Yet, Congo red has no influence on the isolation of curli from curli-producing cells that do not produce cellulose. Sodium dodecyl sulfate can remove Congo red from curli, but not from cellulose. Thus, Congo red binds strongly to cellulose and possibly weakens cellulose interactions with the cell surface, enabling more complete removal of the ECM. The use of Congo red as an extracellular matrix purification aid may be applied broadly to other organisms that assemble extracellular amyloid or cellulosic materials. Graphical abstract Solid-state NMR was used to quantitatively track the isolation of the insoluble amyloid-associated ECM from uropathogenic E. coli and understand the role of Congo red in purification protocols.

Decolorization of different textile dyes by Penicillium simplicissimum and toxicity evaluation after fungal treatment

PubMed Central

Bergsten-Torralba, L.R.; Nishikawa, M.M.; Baptista, D.F.; Magalhães, D.P.; da Silva, M.

2009-01-01

The objective of this study was to investigate the capacity of decolorization and detoxification of the textile dyes Reactive Red 198 (RR198), Reactive Blue 214 (RB214), Reactive Blue 21 (RB21) and the mixture of the three dyes (MXD) by Penicillium simplicissimum INCQS 40211. The dye RB21, a phthalocyanine, was totally decolorized in 2 days, and the others, the monoazo RR198, the diazo RB214 and MXD were decolorized after 7 days by P. simplicissimum. Initially the dye decolorization involved dye adsorption by the biomass followed by degradation. The acute toxicity after fungal treatment was monitored with the microcrustacean Daphnia pulex and measured through Effective Concentration 50% (EC50). P. simplicissimum reduced efficiently the toxicity of RB21 from moderately acutely toxic to minor acutely toxic and it also reduced the toxicity of RB214 and MXD, which remained minor acutely toxic. Nevertheless, the fungus increased the toxicity of RR198 despite of the reduction of MXD toxicity, which included this dye. Thus, P. simplicissimum INCQS 40211 was efficient to decolorize different textile dyes and the mixture of them with a significant reduction of their toxicity. In addition this investigation also demonstrated the need of toxicological assays associated to decolorization experiments. PMID:24031428

Simultaneous photocatalytic and microbial degradation of dye-containing wastewater by a novel g-C3N4-P25/photosynthetic bacteria composite

PubMed Central

Zhang, Xinying; Wu, Yan; Xiao, Gao; Tang, Zhenping; Wang, Meiyin; Liu, Fuchang; Zhu, Xuefeng

2017-01-01

Azo dyes are very resistant to light-induced fading and biodegradation. Existing advanced oxidative pre-treatment methods based on the generation of non-selective radicals cannot efficiently remove these dyes from wastewater streams, and post-treatment oxidative dye removal is problematic because it may leave many byproducts with unknown toxicity profiles in the outgoing water, or cause expensive complete mineralization. These problems could potentially be overcome by combining photocatalysis and biodegradation. A novel visible-light-responsive hybrid dye removal agent featuring both photocatalysts (g-C3N4-P25) and photosynthetic bacteria encapsulated in calcium alginate beads was prepared by self-assembly. This system achieved a removal efficiency of 94% for the dye reactive brilliant red X-3b and also reduced the COD of synthetic wastewater samples by 84.7%, successfully decolorized synthetic dye-contaminated wastewater and reduced its COD, demonstrating the advantages of combining photocatalysis and biocatalysis for wastewater purification. The composite apparently degrades X-3b by initially converting the dye into aniline and phenol derivatives whose aryl moieties are then attacked by free radicals to form alkyl derivatives, preventing the accumulation of aromatic hydrocarbons that might suppress microbial activity. These alkyl intermediates are finally degraded by the photosynthetic bacteria. PMID:28273118

Solar/UV-induced photocatalytic degradation of three commercial textile dyes.

PubMed

Neppolian, B; Choi, H C; Sakthivel, S; Arabindoo, Banumathi; Murugesan, V

2002-01-28

The photocatalytic degradation of three commercial textile dyes with different structure has been investigated using TiO(2) (Degussa P25) photocatalyst in aqueous solution under solar irradiation. Experiments were conducted to optimise various parameters viz. amount of catalyst, concentration of dye, pH and solar light intensity. Degradation of all the dyes were examined by using chemical oxygen demand (COD) method. The degradation efficiency of the three dyes is as follows: Reactive Yellow 17(RY17) > Reactive Red 2(RR2) > Reactive Blue 4 (RB4), respectively. The experimental results indicate that TiO(2) (Degussa P25) is the best catalyst in comparison with other commercial photocatalysts such as, TiO(2) (Merck), ZnO, ZrO(2), WO(3) and CdS. Though the UV irradiation can efficiently degrade the dyes, naturally abundant solar irradiation is also very effective in the mineralisation of dyes. The comparison between thin-film coating and aqueous slurry method reveals that slurry method is more efficient than coating but the problems of leaching and the requirement of separation can be avoided by using coating technique. These observations indicate that all the three dyes could be degraded completely at different time intervals. Hence, it may be a viable technique for the safe disposal of textile wastewater into the water streams.

Near-infrared squaraine dyes for fluorescence enhanced surface assay

PubMed Central

Matveeva, Evgenia G.; Terpetschnig, Ewald A.; Stevens, Megan; Patsenker, Leonid; Kolosova, Olga S.; Gryczynski, Zygmunt; Gryczynski, Ignacy

2009-01-01

Commercially available, near-infrared fluorescent squaraine dyes (Seta-635 and Seta-670) were covalently bound to antibodies and employed insurface enhanced immunoassay. From fluorescence intensity and lifetime changes determined for a surface which had been coated with silver nanoparticles as well as a non-coated glass surface, both labelled compounds exhibited a 15 to 20-fold enhancement of fluorescence on the silver coated surface compared to that achieved on the non-coated surface. In addition, the fluorescence lifetime changes drastically for both labels in the case of silver-coated surfaces. The fluorescence signal enhancement obtained for the two dyes was greater than that previously recorded for Rhodamine Red-X and AlexaFluor-647 labels. PMID:20046935

Preparation and dyeing of super hydrophilic polyethylene terephthalate fabric

NASA Astrophysics Data System (ADS)

Zheng, D. D.; Zhou, J. F.; Xu, F.; Zhang, F. X.; Zhang, G. X.

2016-07-01

In this study, the dyeing properties of PET fabrics modified with sulfuric acid was investigated using disperse red E-4B and disperse blue 2BLNG-L at high temperature and high pressure. The results revealed that the sulfuric acid modification improved the K/S value of dyeing PET fabrics, and the modified PET fabric could be dyed uniformly. The a, b, C, L and H of modified PET fabric were almost the same as that of original PET fabric. The water contact angles were still 0o after 10s, indicating that the hydrophilic property of modified PET fabrics still kept excellent. The wash fastness of dyed PET fabrics after modification was generally good.

Exploring the potential of anaerobic sulfate reduction process in treating sulfonated diazo dye: Microbial community analysis using bar-coded pyrosequencing.

PubMed

Rasool, Kashif; Shahzad, Asif; Lee, Dae Sung

2016-11-15

Anaerobic decolorization and biotransformation of azo dye was investigated in a sulfate-reducing environment. Batch reactor studies were performed with mixed cultures of anaerobic sulfate-reducing bacteria (SRBs) enriched from anaerobic digester sludge. Complete sulfate and color removal were achieved in batch experiments with different initial dye concentrations (50-2500mg/L) and 1000mg/L of sulfate. Induction of various oxidoreductive enzyme activities such as phenol oxidase, veratryl alcohol oxidase, lignin peroxidase, and azo reductase was studied to understand their involvement in dye metabolism under anoxic environment. The degradation of Cotton Red B was confirmed using high-performance liquid chromatography and gas chromatography-mass spectroscopy. Sulfidogenic sludge demonstrated excellent dye degradation and mineralization ability, producing aniline and 1,4-diamino benzene as metabolites. A barcoded 16S rRNA gene-pyrosequencing approach was used to assess the bacterial diversity in the sludge culture and a phylogenetic tree was constructed for sulfate-reducing bacteria. Copyright © 2016 Elsevier B.V. All rights reserved.

Residualization Rates of Near Infrared Dyes for the Rational Design of Molecular Imaging Agents

PubMed Central

Cilliers, Cornelius; Liao, Jianshan; Atangcho, Lydia; Thurber, Greg M.

2016-01-01

Purpose Near infrared (NIR) fluorescence imaging is widely used for tracking antibodies and biomolecules in vivo. Clinical and preclinical applications include intraoperative imaging, tracking therapeutics, and fluorescent labeling as a surrogate for subsequent radiolabeling. Despite their extensive use, one of the fundamental properties of NIR dyes, the residualization rate within cells following internalization, has not been systematically studied. This rate is required for the rational design of probes and proper interpretation of in vivo results. Procedures In this brief report, we measure the cellular residualization rate of eight commonly used dyes encompassing three core structures (cyanine, BODIPY, and oxazine/thiazine/carbopyronin). Results We identify residualizing (half-life > 24 hrs) and non-residualizing dyes (half-life < 24 hrs) in both the far red (~650-680 nm) and near infrared (~740-800 nm) regions. Conclusions This data will allow researchers to independently and rationally select the wavelength and residualizing nature of dyes for molecular imaging agent design. PMID:25869081

Residualization Rates of Near-Infrared Dyes for the Rational Design of Molecular Imaging Agents.

PubMed

Cilliers, Cornelius; Liao, Jianshan; Atangcho, Lydia; Thurber, Greg M

2015-12-01

Near-infrared (NIR) fluorescence imaging is widely used for tracking antibodies and biomolecules in vivo. Clinical and preclinical applications include intraoperative imaging, tracking therapeutics, and fluorescent labeling as a surrogate for subsequent radiolabeling. Despite their extensive use, one of the fundamental properties of NIR dyes, the residualization rate within cells following internalization, has not been systematically studied. This rate is required for the rational design of probes and proper interpretation of in vivo results. In this brief report, we measure the cellular residualization rate of eight commonly used dyes encompassing three core structures (cyanine, boron-dipyrromethene (BODIPY), and oxazine/thiazine/carbopyronin). We identify residualizing (half-life >24 h) and non-residualizing (half-life <24 h) dyes in both the far-red (~650-680 nm) and near-infrared (~740-800 nm) regions. This data will allow researchers to independently and rationally select the wavelength and residualizing nature of dyes for molecular imaging agent design.

Spectroscopic study of congo red and thioflavin binding to amyloid-like proteins

NASA Astrophysics Data System (ADS)

Elhaddaoui, A.; Delacourte, A.; Turrell, S.

1993-03-01

UV-visible, infrared and Raman spectroscopies are used to study the interactions between two histological dyes and poly-L-lysine and insulin. For both dyes, bonding seems to involve their SO 3- groups. However, the NH 2 groups of insulin do not seem to be involved as they are in the case of poly-L-lysine. Moreover, the interactions seem specifically intermolecular in nature and independant of the existence of a β-pleated conformation for the peptide.

Genotoxicity of Dyes Present in Colored Smoke Munitions.

DTIC Science & Technology

1986-07-07

Salmonella bacteria with and without S-9 ..... .......... 32 10. Mutagenic activity of Disperse Red 15 in TA-1538 stain of Salmonella bacteria with and...0.50 4 𔃾 4 MNNG 0 05 - . ..... I . ~*- A191 735 GENOTOXICITY OF DYES PRESENT IN COLORED SMOKE MUNITIONS 2/2 I (U) L VELACE BIOMEDICAL AND ENVIRONMENTAL...for the Salmonella I mutagenicity test. Mutat. Res. 113:173-215. i Perry, P. and S. wolr. 1974. New gieinsa ineLhod for differential staining I of

Combinatorial effects of charge characteristics and hydrophobicity of silk fibroin on the sorption and release of charged dyes.

PubMed

Wongpanit, Panya; Rujiravanit, Ratana

2012-01-01

The present study was designed to examine the influence of the charge characteristics of silk fibroin on the sorption and release of charged dyes by varying the pH values of the sorption and release media as well as types of charged dyes. Negatively charged dyes (phenol red and chromotrope 2R) and positively charged dyes (crystal violet and indoine blue) were used as the model compounds. Silk fibroin films were prepared by using a solution casting technique. The prepared films were then treated with an aqueous methanol solution or annealed with water to control their conformation. The sorption behavior of the model compounds made by the methanol-treated and water-annealed silk fibroin films was investigated. Compared to the water- annealed silk fibroin films, a higher hydrophobicity of the methanol-treated silk fibroin films caused a higher sorption of the hydrophobic dyes. The dye molecules had a fairly high affinity to the silk fibroin film, even though the dye and the matrix possessed the same charge. However, in the presence of two charged groups in a single dye molecule, the electrostatic repulsion become more dominant. Stronger interaction was observed when the charges of the film and the dye were opposite. The results of dye sorption and release experiments showed that the degree of synergism or competition between electrostatic and hydrophobic interactions directly depended on the charges and chemical structure of the dye molecules and the environmental pH conditions of the existing silk fibroin film.

Comparative performance evaluation of Aspergillus lentulus for dye removal through bioaccumulation and biosorption.

PubMed

Kaushik, Prachi; Malik, Anushree

2013-05-01

Dyes used in various industries are discharged into the environment and pose major environmental concern. In the present study, fungal isolate Aspergillus lentulus was utilized for the treatment of various dyes, dye mixtures and dye containing effluent in dual modes, bioaccumulation (employing growing biomass) and biosorption (employing pre-cultivated biomass). The effect of dye toxicity on the growth of the fungal isolate was studied through phase contrast and scanning electron microscopy. Dye biosorption was studied using first and second-order kinetic models. Effects of factors influencing adsorption and isotherm studies were also conducted. During bioaccumulation, good removal was obtained for anionic dyes (100 mg/l), viz. Acid Navy Blue, Fast Red A and Orange-HF dye (99.4 %, 98.8 % and 98.7 %, respectively) in 48 h. Cationic dyes (10 mg/l), viz. Rhodamine B and Methylene Blue, had low removal efficiency (80.3 % [48 h] and 92.7 % [144 h], respectively) as compared to anionic dyes. In addition to this, fungal isolate showed toxicity response towards Methylene Blue by producing larger aggregates of fungal pellets. To overcome the limitations of bioaccumulation, dye removal in biosorption mode was studied. In this mode, significant removal was observed for anionic (96.7-94.3 %) and cationic (35.4-90.9 %) dyes in 24 h. The removal of three anionic dyes and Rhodamine B followed first-order kinetic model whereas removal of Methylene Blue followed second-order kinetic model. Overall, fungal isolate could remove more than 90 % dye from different dye mixtures in bioaccumulation mode and more than 70 % dye in biosorption mode. Moreover, significant color removal from handmade paper unit effluent in bioaccumulation mode (86.4 %) as well as in biosorption mode (77.1 %) was obtained within 24 h. This study validates the potential of fungal isolate, A. lentulus, to be used as the primary organism for treating dye containing wastewater.

A rapid and sensitive fluorimetric β-galactosidase assay for coliform detection using chlorophenol red-β-D-galactopyranoside.

PubMed

Sicard, Clémence; Shek, Norman; White, Dawn; Bowers, Raymond J; Brown, R Stephen; Brennan, John D

2014-09-01

We report on a new fluorimetric assay for β-galactosidase (β-gal) and faecal coliform bacteria that utilizes a long-wavelength dye, chlorophenol red-β-D-galactopyranoside (CPRG), that has been widely used for colorimetric assays. The novel feature of this new assay is the unexpected development of a large fluorescence response from liberated chorophenol red (CPR) upon complexation with poly-L-arginine (pR) in solution. The binding of CPR to pR occurs through the sulphonate group of CPR, causing formation of a charge-transfer complex and up to a 70-fold increase in emission intensity. A major advantage of the assay is the ability to utilize excitation and emission wavelengths in the red end of the spectrum, which avoids common interferences obtained when using UV-absorbing dyes such as 4-methylumbelliferyl-β-D-galactopyranoside. We provide data on the utility of CPRG as a fluorimetric reporter for both β-gal and Escherichia coli ATCC 25922 and demonstrate optimized reaction conditions for rapid and sensitive detection of E. coli at a level of 1 colony-forming unit (cfu)/10 mL after 12 h of culture followed by a 1-h assay, which is below the regulatory limit for testing of recreational water.

Development of a γ-alumina- nanoparticle-functionalized porous polymer monolith for the enrichment of Sudan dyes in red wine samples.

PubMed

Li, Wanjun; Zhou, Xiao; Ye, Juanjuan; Jia, Qiong

2013-10-01

Monolithic materials were synthesized in capillaries by in situ polymerization with N-isopropylacrylamide, glycidyl methacrylate, and ethylene dimethacrylate as the monomers, and methanol and PEG as the porogens. With γ-alumina nanoparticles attached to the surface of the porous monolithic column via epoxide groups, a novel polymer monolith microextraction (PMME) material was prepared with a good mechanical stability and a high extraction capacity. SEM and X-ray photoelectron spectroscopy were employed to characterize the modified monolithic column, demonstrating that γ-alumina nanoparticles were effectively functionalized onto the monolithic column. In addition, a new method was developed for the analysis of Sudan I-IV dyes using PMME coupled with HPLC. In order to obtain the optimum extraction efficiency, the PMME conditions including desorption solvent type, sample pH, sample volume, sample flow rate, and eluent flow rate were investigated. Under the optimum conditions, we obtained acceptable linearities, low LODs, and good intra- and interday RDSs. When applied to the determination of Sudan I-IV dyes in red wine samples, satisfactory recoveries were obtained in the range of 84.0-115.9%. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-throughput measurement of polymer film thickness using optical dyes

NASA Astrophysics Data System (ADS)

Grunlan, Jaime C.; Mehrabi, Ali R.; Ly, Tien

2005-01-01

Optical dyes were added to polymer solutions in an effort to create a technique for high-throughput screening of dry polymer film thickness. Arrays of polystyrene films, cast from a toluene solution, containing methyl red or solvent green were used to demonstrate the feasibility of this technique. Measurements of the peak visible absorbance of each film were converted to thickness using the Beer-Lambert relationship. These absorbance-based thickness calculations agreed within 10% of thickness measured using a micrometer for polystyrene films that were 10-50 µm. At these thicknesses it is believed that the absorbance values are actually more accurate. At least for this solvent-based system, thickness was shown to be accurately measured in a high-throughput manner that could potentially be applied to other equivalent systems. Similar water-based films made with poly(sodium 4-styrenesulfonate) dyed with malachite green oxalate or congo red did not show the same level of agreement with the micrometer measurements. Extensive phase separation between polymer and dye resulted in inflated absorbance values and calculated thickness that was often more than 25% greater than that measured with the micrometer. Only at thicknesses below 15 µm could reasonable accuracy be achieved for the water-based films.

Production of Laccase by a New Myrothecium verrucaria MD-R-16 Isolated from Pigeon Pea [Cajanus cajan (L.) Millsp.] and its Application on Dye Decolorization.

PubMed

Sun, Jiao; Guo, Na; Niu, Li-Li; Wang, Qing-Fang; Zang, Yu-Ping; Zu, Yuan-Gang; Fu, Yu-Jie

2017-04-23

The present study was conducted to screen a laccase-producing fungal endophyte, optimize fermentation conditions, and evaluate the decolorization ability of the laccase. A new fungal endophyte capable of laccase-producing was firstly isolated from pigeon pea and identified as Myrothecium verrucaria based on a ITS-rRNA sequences analysis. Meanwhile, various fermentation parameters on the laccase production were optimized via response surface methodology (RSM). The optimal fermentation conditions were a fermentation time of five days, temperature 30 °C and pH 6.22. Laccase activity reached 16.52 ± 0.18 U/mL under the above conditions. Furthermore, the laccase showed effective decolorization capability toward synthetic dyes (Congo red, Methyl orange, Methyl red, and Crystal violet) in the presence of the redox mediator ABTS, with more than 70% of dyes decolorizing after 24 h of incubation. Additionally, the activity of laccase was relatively stable with pH (4.5-6.5) and a temperature range of 35-55 °C. Therefore, the high laccase production of the strain and the new fungal laccase could provide a promising alterative approach for industrial and environmental applications.

Detoxification and color removal of Congo red by a novel Dietzia sp. (DTS26) - a microcosm approach.

PubMed

Satheesh Babu, S; Mohandass, C; Vijayaraj, A S; Dhale, Mohan A

2015-04-01

The present study deals with the decolorization and detoxification of Congo red (CR) by a novel marine bacterium Dietzia sp. (DTS26) isolated from Divar Island, Goa, India. The maximum decolorization of 94.5% (100 mg L(-1)) was observed under static condition within 30 h at pH 8 and temperature 32±2°C. Bacterially treated samples could enhance the light intensity by 38% and the primary production levels 5 times higher than the untreated. The strain was also able to reduce COD by 86.4% within 30 h at 100 mg L(-1) of CR dye. The degraded metabolites of CR dye were analyzed by FTIR, HPLC, GC-MS and the end product closely matches with 4-amino-3-naphthol-1-sulfonate which is comparatively less toxic than CR. Bioassay experiments conducted in treated samples for Artemia franciscana showed better survival rates (after 72 h) at higher concentration of CR (500 mg L(-1)). This work suggests the potential application of DTS26 in bioremediation of dye wastes and its safe disposal into coastal environment. Copyright © 2015 Elsevier Inc. All rights reserved.

Photocatalytic discoloration of Acid Red 14 aqueous solution using titania nanoparticles immobilized on graphene oxide fabricated plate.

PubMed

Akerdi, Abdollah Gholami; Bahrami, S Hajir; Arami, Mokhtar; Pajootan, Elmira

2016-09-01

Textile industry consumes remarkable amounts of water during various operations. A significant portion of the water discharge to environment is in the form of colored contaminant. The present research reports the photocatalytic degradation of anionic dye effluent using immobilized TiO2 nanoparticle on graphene oxide (GO) fabricated carbon electrodes. Acid Red 14 (AR 14) was used as model compound. Graphene oxide nanosheets were synthesized from graphite powder using modified Hummer's method. The nanosheets were characterized with field emission scanning electron microscope (FESEM) images, X-ray diffraction (XRD) and FTIR spectrum. The GO nanoparticles were deposited on carbon electrode (GO-CE) by electrochemical deposition (ECD) method and used as catalyst bed. TiO2 nanoparticles were fixed on the bed (GO-CE- TiO2) with thermal process. Photocatalytic processes were carried out using a 500 ml solution containing dye in batch mode. Each photocatalytic treatment were carried out for 120 min. Effect of dye concentration (mg/L), pH of solution, time (min) and TiO2 content (g/L) on the photocatalytic decolorization was investigated. Copyright © 2016 Elsevier Ltd. All rights reserved.

Photocatalytic detoxification of Acid Red 18 by modified ZnO catalyst under sunlight irradiation

NASA Astrophysics Data System (ADS)

Senthilraja, A.; Subash, B.; Dhatshanamurthi, P.; Swaminathan, M.; Shanthi, M.

2015-03-01

In this work, hybrid structured Bi-Au-ZnO composite was prepared by precipitation-decomposition method. This method is mild, economical and efficient. Bi-Au-ZnO was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectrum (EDS), diffuse reflectance spectra (DRS), photoluminescence spectra (PL) and BET surface area measurements. Photocatalytic activity of Bi-Au-ZnO was evaluated by irradiating the Acid Red 18 (AR 18) dye solution under sun light. Heterostructured Bi-Au-ZnO photocatalyst showed higher photocatalytic activity than those of individual Bi-ZnO, Au-ZnO, bare ZnO, and TiO2-P25 at pH 11. The effects of operational parameters such as the amount of catalyst dosage, dye concentration, initial pH on photo mineralization of AR 18 dye have been analyzed. The mineralization of AR 18 has been confirmed by chemical oxygen demand (COD) measurements. A possible mechanism is proposed for the degradation of AR 18 under sun light. Finally, Bi-Au-ZnO heterojunction photocatalyst was more stable and could be easily recycled several times opening a new avenue for potential industrial applications.

Biphasic TiO2 nanoparticles decorated graphene nanosheets for visible light driven photocatalytic degradation of organic dyes

NASA Astrophysics Data System (ADS)

Alamelu, K.; Raja, V.; Shiamala, L.; Jaffar Ali, B. M.

2018-02-01

We present characterization of biphasic TiO2 nanoparticles and its graphene nanocomposite synthesized by cost effective, hydrothermal method. The structural properties and morphology of the samples were characterized by series of spectroscopic and microscopic techniques. Introducing high surface area graphene could suppress the electron hole pair recombination rate in the nanocomposite. Further, the nanocomposite shows red-shift of the absorption edge and contract of the band gap from 2.98 eV to 2.85 eV. We have characterized its photocatalytic activity under natural sunlight and UV filtered sunlight irradiation. Data reveal graphene-TiO2 composite exhibit about 15 and 3.5 folds increase in degradability of Congo red and Methylene Blue dyes, respectively, comparison to pristine TiO2. This underscores the marginal effect of UV component of sunlight on the degradation ability of composite, implying its increased efficiency in harnessing visible region of solar spectrum. We have thus developed a visible light active graphene composite catalyst that can degrade both cationic and anionic dyes and making it potentially useful in environmental remediation and water splitting applications, under direct sunlight.

Organic Chemicals: Angels or Goblins?

ERIC Educational Resources Information Center

Ferguson, Lloyd N.

1978-01-01

Discusses some of the controversial organic chemical substances such as DDT, Red Dye No. 2, DES, Tris, Laetrile, cyclamate, and saccharin. Concludes that the use of some has to be considered on a benefit/risk ratio. (GA)

AcT-2: a novel myotropic and antimicrobial type 2 tryptophyllin from the skin secretion of the Central American red-eyed leaf frog, Agalychnis callidryas.

PubMed

Ge, Lilin; Lyu, Peng; Zhou, Mei; Zhang, Huiling; Wan, Yuantai; Li, Bin; Li, Renjie; Wang, Lei; Chen, Tianbao; Shaw, Chris

2014-01-01

Tryptophyllins are a diverse family of amphibian peptides originally found in extracts of phyllomedusine frog skin by chemical means. Their biological activities remain obscure. Here we describe the isolation and preliminary pharmacological characterization of a novel type 2 tryptophyllin, named AcT-2, from the skin secretion of the red-eyed leaf frog, Agalychnis callidryas. The peptide was initially identified during smooth muscle pharmacological screening of skin secretion HPLC fractions and the unique primary structure--GMRPPWF-NH2--was established by both Edman degradation and electrospray MS/MS fragmentation sequencing. A. cDNA encoding the biosynthetic precursor of AcT-2 was successfully cloned from a skin secretion-derived cDNA library by means of RACE PCR and this contained an open-reading frame consisting of 62 amino acid residues with a single AcT-2 encoding sequence located towards the C-terminus. A synthetic replicate of AcT-2 was found to relax arterial smooth muscle (EC50 = 5.1 nM) and to contract rat urinary bladder smooth muscle (EC50 = 9.3 μ M). The peptide could also inhibit the growth of the microorganisms, Staphylococcus aureus, (MIC = 256 mg/L) Escherichia coli (MIC = 512 mg/L), and Candida albicans (128 mg/L). AcT-2 is thus the first amphibian skin tryptophyllin found to possess both myotropic and antimicrobial activities.

Photocatalytic degradation of organic dyes by Er3+: YAlO3/Co- and Fe-doped ZnO coated composites under solar irradiation

NASA Astrophysics Data System (ADS)

Chen, Yang; Lu, Chunxiao; Tang, Liang; Song, Yahui; Wei, Shengnan; Rong, Yang; Zhang, Zhaohong; Wang, Jun

2016-12-01

In this work, the Er3+: YAlO3/Co- and Fe-doped ZnO coated composites were prepared by the sol-gel method. Then, they were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDX). Photo-degradation of azo fuchsine (AF) as a model dye under solar light irradiation was studied to evaluate the photocatalytic activity of the Er3+: YAlO3/Co- and Fe-doped ZnO coated composites. It was found that the photocatalytic activity of Co- and Fe-doped ZnO composites can be obviously enhanced by upconversion luminescence agent (Er3+: YAlO3). Besides, the photocatalytic activity of Er3+: YAlO3/Fe-doped ZnO is better than that of Er3+: YAlO3/Co-doped ZnO. The influence of experiment conditions, such as the concentration of Er3+: YAlO3, heat-treatment temperature and time on the photocatalytic activity of the Er3+: YAlO3/Co- and Fe-doped ZnO coated composites was studied. In addition, the effects of solar light irradiation time, dye initial concentration, Er3+: YAlO3/Co- and Fe-doped ZnO amount on the photocatalytic degradation of azo fuchsine in aqueous solution were investigated in detail. Simultaneously, some other organic dyes, such as Methyl Orange (MO), Rhodamine B (RM-B), Acid Red B (AR-B), Congo Red (CR), and Methyl Blue (MB) were also studied. The possible excitation principle of Er3+: YAlO3/Co- and Fe-doped ZnO coated composites under solar light irradiation and the photocatalytic degradation mechanism of organic dyes were discussed.

Removal of reactive red-120 and 4-(2-pyridylazo) resorcinol from aqueous samples by Fe3O4 magnetic nanoparticles using ionic liquid as modifier.

PubMed

Absalan, Ghodratollah; Asadi, Mozaffar; Kamran, Sedigheh; Sheikhian, Leila; Goltz, Douglas M

2011-08-30

The nanoparticles of Fe(3)O(4) as well as the binary nanoparticles of ionic liquid and Fe(3)O(4) (IL-Fe(3)O(4)) were synthesized for removal of reactive red 120 (RR-120) and 4-(2-pyridylazo) resorcinol (PAR) as model azo dyes from aqueous solutions. The mean size and the surface morphology of the nanoparticles were characterized by TEM, DLS, XRD, FTIR and TGA techniques. Adsorption of RR-120 and PAR was studied in a batch reactor at different experimental conditions such as nanoparticle dosage, dye concentration, pH of the solution, ionic strength, and contact time. Experimental results indicated that the IL-Fe(3)O(4) nanoparticles had removed more than 98% of both dyes under the optimum operational conditions of a dosage of 60mg, a pH of 2.5, and a contact time of 2min when initial dyes concentrations of 10-200mg L(-1) were used. The maximum adsorption capacity of IL-Fe(3)O(4) was 166.67 and 49.26mg g(-1) for RR-120 and PAR, respectively. The isotherm experiments revealed that the Langmuir model attained better fits to the equilibrium data than the Freundlich model. The Langmuir adsorption constants were 5.99 and 3.62L mg(-1) for adsorptions of RR-120 and PAR, respectively. Both adsorption processes were endothermic and dyes could be desorbed from IL-Fe(3)O(4) by using a mixed NaCl-acetone solution and adsorbent was reusable. Copyright © 2011 Elsevier B.V. All rights reserved.

Cochineal dye-induced immediate allergy: Review of Japanese cases and proposed new diagnostic chart.

PubMed

Takeo, Naoko; Nakamura, Masashi; Nakayama, Satoshi; Okamoto, Osamu; Sugimoto, Naoki; Sugiura, Shinichi; Sato, Nayu; Harada, Susumu; Yamaguchi, Masao; Mitsui, Naoya; Kubota, Yumiko; Suzuki, Kayoko; Terada, Makoto; Nagai, Akiyo; Sowa-Osako, Junko; Hatano, Yutaka; Akiyama, Hiroshi; Yagami, Akiko; Fujiwara, Sakuhei; Matsunaga, Kayoko

2018-04-25

Cochineal dye is used worldwide as a red coloring in foods, drinks, cosmetics, quasi-drugs, and drugs. The main component of the red color is carminic acid (CA). Carmine is an aluminum- or calcium-chelated product of CA. CA and carmine usually contain contaminating proteins, including a 38-kDa protein thought to be the primary allergen. Severe allergic reactions manifest as anaphylaxis. The aim of this study was to review all Japanese reported cases and propose useful diagnostic chart. All reported Japanese cases of cochineal dye-induced immediate allergy were reviewed, and newly registered cases were examined by skin prick test (SPT) with cochineal extract (CE) and measurement of CE and carmine-specific serum IgE test. Two-dimensional (2D) western blotting using patient serum was conducted to identify the antigen. Twenty-two Japanese cases have been reported. SPT and the level of specific IgE test indicated that six cases should be newly registered as cochineal dye allergy. All cases were adult females, and all cases except three involved anaphylaxis; 13 cases involved past history of local symptoms associated with cosmetics use. Japanese strawberry juice and fish-meat sausage, and European processed foods (especially macarons made in France) and drinks were recent major sources of allergen. 2D western blotting showed that patient IgE reacted to the 38-kDa protein and other proteins. Serum from healthy controls also weakly reacted with these proteins. SPT with CE and determination of the level of CE and carmine-specific IgE test are useful methods for the diagnosis of cochineal dye allergy. Copyright © 2018 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Occurrence and risk assessment of an azo dye - The case of Disperse Red 1.

PubMed

Vacchi, Francine Inforçato; Von der Ohe, Peter Carsten; Albuquerque, Anjaína Fernandes de; Vendemiatti, Josiane Aparecida de Souza; Azevedo, Carina Cristina Jesus; Honório, Jaqueline Gonçalves; Silva, Bianca Ferreira da; Zanoni, Maria Valnice Boldrin; Henry, Theodore B; Nogueira, Antonio J; Umbuzeiro, Gisela de Aragão

2016-08-01

Water quality criteria to protect aquatic life are not available for most disperse dyes which are often used as commercial mixtures in textile coloration. In this study, the acute and chronic toxicity of the commercial dye Disperse Red 1 (DR1) to eight aquatic organisms from four trophic levels was evaluated. A safety threshold, i.e. Predicted No-Effect Concentration (PNEC), was derived based on the toxicity information of the commercial product and the purified dye. This approach was possible because the toxicity of DR1 was accounting for most of the toxicity of the commercial mixture. A long-term PNEC of 60 ng L(-1) was proposed, based on the most sensitive chronic endpoint for Daphnia similis. A short-term PNEC of 1800 ng L(-1) was proposed based on the most sensitive acute endpoint also for Daphnia similis. Both key studies have been evaluated with the new "Criteria for Reporting and Evaluating ecotoxicity Data" (CRED) methodology, applying more objective criteria to assess the quality of toxicity tests, resulting in two reliable and relevant endpoints with only minor restrictions. HPLC-MS/MS was used to quantify the occurrence of DR1 in river waters of three sites, influenced by textile industry discharges, resulting in a concentration range of 50-500 ng L(-1). The risk quotients for DR1 obtained in this work suggest that this dye can pose a potential risk to freshwater biota. To reduce uncertainty of the derived PNEC, a fish partial or full lifecycle study should be performed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Amplified spontaneous emission of pyranyliden derivatives in PVK matrix

NASA Astrophysics Data System (ADS)

Vembris, Aivars; Zarinsh, Elmars; Kokars, Valdis

2016-04-01

One of the well-known red light emitting laser dyes is 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4Hpyran (DCM). Amplified spontaneous emission (ASE) has been widely investigated of DCM molecules or its derivatives in polymer or low molecular weight matrix. The main issue for these molecules is aggregation which limits doping concentration in matrix. Lowest ASE threshold values within concentration range of 2 and 4 wt% were obtained. In this work ASE properties of two original DCM derivatives in poly(N-vinylcarbazole) (PVK) at various concentrations will be discussed. One of the derivatives is the same DCM dye with replaced butyl groups at electron donor part with bulky trytiloxyethyl groups (DWK-1). These groups do not influence electron transitions in the dye but prevent aggregation of the molecules. Second derivative (DWK-2) consists of two equal donor groups with the attached trytiloxyethyl groups. All results were compared with DCM:PVK system. Photoluminescence quantum yield (PLQY) is almost three times larger for DWK-1 concentration up to 20wt% with respect to DCM systems. PLQY was saturated on 0.06 at higher DWK-1 concentrations. Bulky trytiloxyethyl groups prevent aggregation of the molecules thus decreasing interaction between dyes and numbers of non-radiative decays. Red shift of photoluminescence and amplified spontaneous emission at higher concentrations were observed due to the solid state solvation effect. Increases of dye density in matrix with smaller lose in PLQY resulted in low ASE threshold energy. The lowest threshold value was obtained around 29 μJ/cm2 in DWK-1:PVK films.

Performance comparison of three types of high-speed counter-current chromatographs for the separation of components of hydrophilic and hydrophobic color additives.

PubMed

Weisz, Adrian; Ito, Yoichiro

2011-09-09

The performance of three types of high-speed counter-current chromatography (HSCCC) instruments was assessed for their use in separating components in hydrophilic and hydrophobic dye mixtures. The HSCCC instruments compared were: (i) a J-type coil planet centrifuge (CPC) system with a conventional multilayer-coil column, (ii) a J-type CPC system with a spiral-tube assembly-coil column, and (iii) a cross-axis CPC system with a multilayer-coil column. The hydrophilic dye mixture consisted of a sample of FD&C Blue No. 2 that contained mainly two isomeric components, 5,5'- and 5,7'-disulfonated indigo, in the ratio of ∼7:1. The hydrophobic dye mixture consisted of a sample of D&C Red No. 17 (mainly Sudan III) and Sudan II in the ratio of ∼4:1. The two-phase solvent systems used for these separations were 1-butanol/1.3M HCl and hexane/acetonitrile. Each of the three instruments was used in two experiments for the hydrophilic dye mixture and two for the hydrophobic dye mixture, for a total of 12 experiments. In one set of experiments, the lower phase was used as the mobile phase, and in the second set of experiments, the upper phase was used as the mobile phase. The results suggest that: (a) use of a J-type instrument with either a multilayer-coil column or a spiral-tube assembly column, applying the lower phase as the mobile phase, is preferable for separating the hydrophilic components of FD&C Blue No. 2; and (b) use of a J-type instrument with multilayer-coil column, while applying either the upper phase or the lower phase as the mobile phase, is preferable for separating the hydrophobic dye mixture of D&C Red No. 17 and Sudan II. Published by Elsevier B.V.

Stimulated emission and optical properties of pyranyliden fragment containing compounds in PVK matrix

NASA Astrophysics Data System (ADS)

Vembris, Aivars; Zarins, Elmars; Kokars, Valdis

2017-10-01

Organic solid state lasers are thoughtfully investigated due to their potential applications in communication, sensors, biomedicine, etc. Low amplified spontaneous emission (ASE) excitation threshold value is essential for further use of the material in devices. Intramolecular interaction limits high molecule density load in the matrix. It is the case of the well-known red light emitting laser dye - 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM). The lowest ASE threshold value of the mentioned laser dye could be obtained within the concentration range between 2 and 4 wt%. At higher concentration threshold energy drastically increases. In this work optical and ASE properties of three original DCM derivatives in poly(N-vinylcarbazole) (PVK) at various concentrations will be discussed. One of the derivatives is modified DCM dye in which the methyl substituents in the electron donor part have been replaced with bulky trityloxyethyl groups (DWK-1). These sterically significant functional groups do not influence electron transitions in the dye but prevent aggregation of the molecules. The chemical structure of the second investigated compound is similar to DWK-1 where the methyl group is replaced with the tert-butyl substituent (DWK-1TB). The third derivative (DWK-2) consists of two N,N-di(trityloxyethyl)amino electron donor groups. All results were compared with DCM:PVK system. Photoluminescence quantum yield (PLQY) is up to ten times larger for DWK-1TB with respect to DCM systems. Bulky trityloxyethyl groups prevent aggregation of the molecules thus decreasing interaction between dyes and amount of non-radiative decays. The red shift of the photoluminescence and amplified spontaneous emission at higher concentrations were observed due to the solid state solvation effect. The increase of the investigated dye density in the matrix with a smaller reduction in PLQY resulted in low ASE threshold energy. The lowest threshold value was obtained around 21 μJ/cm2 (2.1 kW/cm2) in DWK-1TB:PVK films.

Habitat Characteristics of Active and Abandoned Red-Cockaded Woodpecker Colonies

Treesearch

Susan C. Loeb; William D. Pepper; Arlene T. Doyle

1992-01-01

Active red-cockaded woodpecker (Picoides borealis) colonies in the Piedmont of Georgia are mature pine stands (mean age = 87 ± 1 yr old) with relatively sparse midstories (mean basal area = 31 ± 3 ft2/ac). Active and abandoned colony sites have similar overstory characteristics, but midstories are significantly denser in...

Polar red-emitting rhodamine dyes with reactive groups: synthesis, photophysical properties, and two-color STED nanoscopy applications.

PubMed

Kolmakov, Kirill; Wurm, Christian A; Meineke, Dirk N H; Göttfert, Fabian; Boyarskiy, Vadim P; Belov, Vladimir N; Hell, Stefan W

2014-01-03

The synthesis, reactivity, and photophysical properties of new rhodamines with intense red fluorescence, two polar residues (hydroxyls, primary phosphates, or sulfonic acid groups), and improved hydrolytic stability of the amino-reactive sites (NHS esters or mixed N-succinimidyl carbonates) are reported. All fluorophores contain an N-alkyl-1,2-dihydro-2,2,4-trimethylquinoline fragment, and most of them bear a fully substituted tetrafluoro phenyl ring with a secondary carboxamide group. The absorption and emission maxima in water are in the range of 635-639 and 655-659 nm, respectively. A vastly simplified approach to red-emitting rhodamines with two phosphate groups that are compatible with diverse functional linkers was developed. As an example, a phosphorylated dye with an azide residue was prepared and was used in a click reaction with a strained alkyne bearing an N-hydroxysuccinimid (NHS) ester group. This method bypasses the undesired activation of phosphate groups, and gives an amphiphilic amino-reactive dye, the solubility and distribution of which between aqueous and organic phases can be controlled by varying the pH. The presence of two hydroxyl groups and a phenyl ring with two carboxyl residues in the dyes with another substitution pattern is sufficient for providing the hydrophilic properties. Selective formation of a mono-N-hydroxysuccinimidyl ester from 5-carboxy isomer of this rhodamine is reported. The fluorescence quantum yields varied from 58 to 92% for free fluorophores, and amounted to 18-64% for antibody conjugates in aqueous buffers. The brightness and photostability of these fluorophores facilitated two-color stimulated emission depletion (STED) fluorescence nanoscopy of biological samples with high contrast and minimal background. Selecting a pair of fluorophores with absorption/emission bands at 579/609 and 635/655 nm enabled two-color channels with low cross-talk and negligible background at approximately 40 nm resolution. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Influence of selected fluorescent dyes on small aquatic organisms

NASA Astrophysics Data System (ADS)

Rowiński, Paweł; Chrzanowski, Marcin

2011-02-01

Rhodamine B and Rhodamine WT are fluorescent dyes commonly used as tracers in hydrological investigations. Since introducing intensely red substances into rivers raises understandable doubts of ecological nature, the authors aimed at examining the influence of these dyes on small water fauna using bioindication methods. Quantitative results, calculated with the use of Bliss-Weber probit statistical method, were achieved by means of standardized ecotoxicological tests containing ready-to-hatch resting forms of fairy shrimp (Thamnocephalus platyurus). Qualitative studies included observation of water flea crustacean (Daphnia magna) and horned planorbis snail (Planorbis corneus), both typically present in rivers and representative for temperate climate, as well as guppy fish (Poecilla reticulata), paramecium protozoan (Paramaecium caudatum) and the above-mentioned fairy shrimp. The investigation revealed that both dyes in concentrations used for hydrological purposes are low enough to exert almost no toxic impact on water fauna considered.

Ability of a montmorillonitic clay to interact with cationic and anionic dyes in aqueous solutions

NASA Astrophysics Data System (ADS)

Pleşa Chicinaş, R.; Bedelean, H.; Stefan, R.; Măicăneanu, A.

2018-02-01

A montmorillonitic clay in raw and treated forms (size-fractionated, organoclay, Al pillared) was evaluated as adsorbent for cationic (toluidine blue - TB and malachite green - MG) and anionic (Congo red - CR) dyes. A thorough characterization using XRD, SEM-EDS, N2 adsorption, and FTIR of the considered samples was realized, all highlighting the structural changes after various treatments. UV-VIS analysis demonstrated the interaction between dyes and the adsorbent surface. The investigation of the effects of various experimental parameters using a batch adsorption technique showed that ON has a high adsorption potential for cationic dyes (33 and 39 mg/g in case of TB and MG, respectively). The kinetic study indicated that the adsorption process followed the pseudo-second-order model, while Freundlich isotherm showed a favorable adsorption. The calculated values of Gibbs free energy suggested also that the adsorption is spontaneous and is more favorable at higher temperatures.

[Reactions to fragrances and textiles].

PubMed

Hausen, B M

1987-12-01

Allergic reactions to fragrances are caused by perfumes and perfume-containing items of our environment. The most important allergen is cinnamic aldehyde. By means of the mixed perfume test recommended by the International Contact Dermatitis Research Group (ICDRG), however, we are not able to detect more than half of the patients suffering from perfume allergy. Thus we suggest to make use of two new test series comprising most of the relevant fragrance components. Allergic reactions to textiles are mostly due to textile dyes. Special regard must be given to the disperse dyes of the azo group in nylon stockings and tights. The three most important allergens are disperse yellow 3, disperse orange 3, and disperse red 1. According to our experiments, the sensitizing potency of these dyes is comparatively low. In contrast, two recently introduced azo dyes (disperse blue 106 and 124), which are mainly used in blouses and trousers, proved to be strong sensitizers.

Chronic toxicity of azo and anthracenedione dyes to embryo-larval fathead minnow.

PubMed

Parrott, Joanne L; Bartlett, Adrienne J; Balakrishnan, Vimal K

2016-03-01

The toxicity of selected azo and anthracenedione dyes was studied using chronic exposures of embryo-larval fathead minnows (Pimephales promelas). Newly fertilized fathead minnow embryos were exposed through the egg stage, past hatching, through the larval stage (until 14 days post-hatch), with dye solutions renewed daily. The anthracenedione dyes Acid Blue 80 (AB80) and Acid Blue 129 (AB129) caused no effects in larval fish at the highest measured concentrations tested of 7700 and 6700 μg/L, respectively. Both azo dyes Disperse Yellow 7 (DY7) and Sudan Red G (SRG) decreased survival of larval fish, with LC50s (based on measured concentrations of dyes in fish exposure water) of 25.4 μg/L for DY7 and 16.7 μg/L for SRG. Exposure to both azo dyes caused a delayed response, with larval fish succumbing 4-10 days after hatch. If the exposures were ended at the embryo stage or just after hatch, the potency of these two dyes would be greatly underestimated. Concentrations of dyes that we measured entering the Canadian environment were much lower than those that affected larval fish survival in the current tests. In a total of 162 samples of different municipal wastewater effluents from across Canada assessed for these dyes, all were below detection limits. The similarities of the structures and larval fish responses for the two azo and two anthracenedione dyes in this study support the use of read-across data for risk assessment of these classes of compounds. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Estrogenic and anti-estrogenic activity of 23 commercial textile dyes.

PubMed

Bazin, Ingrid; Ibn Hadj Hassine, Aziza; Haj Hamouda, Yosra; Mnif, Wissem; Bartegi, Ahgleb; Lopez-Ferber, Miguel; De Waard, Michel; Gonzalez, Catherine

2012-11-01

The presence of dyes in wastewater effluent of textile industry is well documented. In contrast, the endocrine disrupting effects of these dyes and wastewater effluent have been poorly investigated. Herein, we studied twenty-three commercial dyes, usually used in the textile industry, and extracts of blue jean textile wastewater samples were evaluated for their agonistic and antagonistic estrogen activity. Total estrogenic and anti-estrogenic activities were measured using the Yeast Estrogen Screen bioassay (YES) that evaluates estrogen receptor binding-dependent transcriptional and translational activities. The estrogenic potencies of the dyes and wastewater samples were evaluated by dose-response curves and compared to the dose-response curve of 17β-estradiol (E2), the reference compound. The dose-dependent anti-estrogenic activities of the dyes and wastewater samples were normalized to the known antagonistic effect of 4-hydroxytamoxifen (4-OHT) on the induction of the lac Z reporter gene by E2. About half azo textile dyes have anti-estrogenic activity with the most active being Blue HFRL. Most azo dyes however have no or weak estrogenic activity. E2/dye or E2/waste water ER competitive binding assays show activity of Blue HFRL, benzopurpurine 4B, Everzol Navy Blue FBN, direct red 89 BNL 200% and waste water samples indicating a mechanism of action common to E2. Our results indicate that several textile dyes are potential endocrine disrupting agents. The presence of some of these dyes in textile industry wastewater may thus impact the aquatic ecosystem. Copyright © 2012 Elsevier Inc. All rights reserved.

New insight of hybrid membrane to degrade Congo red and Reactive yellow under sunlight.

PubMed

Rajeswari, A; Jackcina Stobel Christy, E; Pius, Anitha

2018-02-01

A study was carried out to investigate the degradation of organic contaminants (Congo red and Reactive yellow - 105) using cellulose acetate - polystyrene (CA-PS) membrane with and without ZnO impregnation. Scanning electron microscope (SEM), electron dispersive analysis of X-rays (EDAX), Fourier transform infrared spectrometer (FTIR), atomic force microscope (AFM) and thermogravimeric analysis (TG-DTA) analysis were carried out to characterize bare and ZnO impregnated CA-PS membranes. Membrane efficiency was also tested for pure water flux and antifouling performance. The modified membrane showed almost 85% water flux recovery. Blending of ZnO nanoparticles to CA-PS matrix could decrease membrane fouling and increase permeation quality of the membrane with above 90% of photocatalytic degradation efficiency for dyes. The rate of degradation of dyes was observed using UV-Vis spectrometer. Reusability of CA-PS-ZnO membrane was studied and no significant change was noted in the degradation efficiency until fourth cycle. Langmuir-Hinshelwood kinetic model well describes the photo degradation capacity and the degradation of dyes CR and RY - 105 exhibited pseudo-first order kinetics. The regression coefficient (R) of CR and RY - 105 found to be 0.99. The novelty of the prepared CA-PS-ZnO membrane is that it has better efficiency and high thermal stability than our previously reported material. Therefore, ZnO impregnated CA-PS membrane had proved to be an innovative alternative for the degradation of CR and RY - 105 dyes. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of sustainable dye adsorption system using nutraceutical industrial fennel seed spent-studies using Congo red dye.

PubMed

Taqui, Syed Noeman; Yahya, Rosiyah; Hassan, Aziz; Nayak, Nayan; Syed, Akheel Ahmed

2017-07-03

Fennel seed spent (FSS)-an inexpensive nutraceutical industrial spent has been used as an efficient biosorbent for the removal of Congo red (CR) from aqueous media. Results show that the conditions for maximum adsorption would be pH 2-4 and 30°C were ideal for maximum adsorption. Based on regression fitting of the data, it was determined that the Sips isotherm (R 2 = 0.994, χ 2 = 0.5) adequately described the mechanism of adsorption, suggesting that the adsorption occurs homogeneously with favorable interaction between layers with favorable interaction between layers. Thermodynamic analysis showed that the adsorption is favorable (negative values for ΔG°) and endothermic (ΔH° = 12-20 kJ mol -1 ) for initial dye concentrations of 25, 50, and 100 ppm. The low ΔH° value indicates that the adsorption is a physical process involving weak chemical interactions like hydrogen bonds and van der Waals interactions. The kinetics revealed that the adsorption process showed pseudo-second-order tendencies with the equal influence of intraparticle as well as film diffusion. The scanning electron microscopy images of FSS show a highly fibrous matrix with a hierarchical porous structure. The Fourier transform infrared spectroscopy analysis of the spent confirmed the presence of cellulosic and lignocellulosic matter, giving it both hydrophilic and hydrophobic properties. The investigations indicate that FSS is a cost-effective and efficient biosorbent for the remediation of toxic CR dye.

Removal of Direct Red 23 from aqueous solution using corn stalks: Isotherms, kinetics and thermodynamic studies

NASA Astrophysics Data System (ADS)

Fathi, M. R.; Asfaram, A.; Farhangi, A.

2015-01-01

The objective of this study was to assess the suitability and efficiency of corn stalk (CS) for the removal of diazo dye Direct Red 23 (DR23) from aqueous solutions. The effect of different variables in the batch method as a function of solution pH, contact time, initial dye concentration, CS amount, temperature, and so forth by the optimization method has been investigated. The color reduction was monitored by spectrophotometry at 503 nm before and after DR23 adsorption on the CS, and the removal percentage was calculated using the difference in absorbance. The sorption processes followed the pseudo second order in addition to intraparticle diffusion kinetics models with a good correlation coefficient with the overall entire adsorption of DR23 on adsorbent. The experimental equilibrium data were tested by four widely used isotherm models namely, Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich (D-R). It was found that adsorption of DR23 on CS well with the Freindlich isotherm model, implying monolayer coverage of dye molecules onto the surface of the adsorbent. More than 99% removal efficiency was obtained within 10 min at adsorbent dose of 0.2 g for initial dye concentration of 10-90 mg L-1 at pH 3. Various thermodynamic parameters, such as Gibbs free energy, entropy, and enthalpy, of the ongoing adsorption process have been calculated. Judgment based on the obtained results of thermodynamic values shows the spontaneous and endothermic nature adsorption processes on adsorbent.

A rapid, naked-eye detection of hypochlorite and bisulfite using a robust and highly-photostable indicator dye Quinaldine Red in aqueous medium

NASA Astrophysics Data System (ADS)

Dutta, Tanoy; Chandra, Falguni; Koner, Apurba L.

2018-02-01

A ;naked-eye; detection of health hazardous bisulfite (HSO3-) and hypochlorite (ClO-) using an indicator dye (Quinaldine Red, QR) in a wide range of pH is demonstrated. The molecule contains a quinoline moiety linked to an N,N-dimethylaniline moiety with a conjugated double bond. Treatment of QR with HSO3- and ClO-, in aqueous solution at near-neutral pH, resulted in a colorless product with high selectivity and sensitivity. The detection limit was 47.8 μM and 0.2 μM for HSO3- and ClO- respectively. However, ClO- was 50 times more sensitive and with 2 times faster response compared to HSO3-. The detail characterization and related analysis demonstrate the potential of QR for a rapid, robust and highly efficient colorimetric sensor for the practical applications to detect hypochlorite in water samples.

Magnetic polymer microcapsules loaded with Nile Red fluorescent dye

NASA Astrophysics Data System (ADS)

Bartel, Marta; Wysocka, Barbara; Krug, Pamela; Kępińska, Daria; Kijewska, Krystyna; Blanchard, Gary J.; Kaczyńska, Katarzyna; Lubelska, Katarzyna; Wiktorska, Katarzyna; Głowala, Paulina; Wilczek, Marcin; Pisarek, Marcin; Szczytko, Jacek; Twardowski, Andrzej; Mazur, Maciej

2018-04-01

Fabrication of multifunctional smart vehicles for drug delivery is a fascinating challenge of multidisciplinary research at the crossroads of materials science, physics and biology. We demonstrate a prototypical microcapsule system that is capable of encapsulating hydrophobic molecules and at the same time reveals magnetic properties. The microcapsules are prepared using a templated synthesis approach where the molecules to be encapsulated (Nile Red) are present in the organic droplets that are suspended in the polymerization solution which also contains magnetic nanoparticles. The polymer (polypyrrole) grows on the surface of organic droplets encapsulating the fluorescent dye in the core of the formed microcapsule which incorporates the nanoparticles into its wall. For characterization of the resulting structures a range of complementary physicochemical methodology is used including optical and electron microscopy, magnetometry, 1H NMR and spectroscopy in the visible and X-ray spectral ranges. Moreover, the microcapsules have been examined in biological environment in in vitro and in vivo studies.

Investigating noncovalent squarylium dye-protein interactions by capillary electrophoresis-frontal analysis.

PubMed

Yan, Weiying; Colyer, Christa L

2006-11-24

Noncovalent interactions between fluorescent probe molecules and protein analyte molecules, which typically occur with great speed and minimal sample handling, form the basis of many high sensitivity analytical techniques. Understanding the nature of these interactions and the composition of the resulting complexes represents an important area of study that can be facilitated by capillary electrophoresis (CE). Specifically, we will present how frontal analysis (FA) and Hummel-Dreyer (HD) methods can be implemented with CE to determine association constants and stoichiometries of noncovalent complexes of the red luminescent squarylium dye Red-1c with bovine serum albumin (BSA) and beta-lactoglobulin A. By adjusting solution conditions, such as pH or ionic strength, it is possible to selectively modify the binding process. As such, conditions for optimal selectivity for labeling reactions can be established by capillary electrophoresis-frontal analysis (CE-FA) investigations.

Infra-red technique for cerebral blood flow: comparison with /sup 133/Xenon clearance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colacino, J.M.; Grubb, B.; Joebsis, F.F.

A rapid infra-red optical technique has been developed for the measurement of cerebral blood flow. The method measures optical density changes across the intact skull during the passage of a bolus of the dye. Cardio-Green (CG). The clearance curves obtained for CG boluses are very short (less than 30 sec) in comparison with those obtained with tracers such as /sup 133/Xenon (10-30 min) that distribute into cerebral tissue. The volume of distribution of CG is totally intravascular, and the dye is relatively slowly cleared from the body. The important advantages of this spectrophotometric technique are its speed, versatility, and themore » avoidance of radioactive materials. The differential spectrophotometer used in this study, with trivial modifications, has been used to monitor changes in brain blood volume, oxygen saturation of hemoglobin, and cortical mitochondrial respiratory function, which illustrate the versatility of the technique for neurological assessments.« less

The effect of operational parameters on the photocatalytic degradation of Congo red organic dye using ZnO-CdS core-shell nano-structure coated on glass by Doctor Blade method.

PubMed

Habibi, Mohammad Hossein; Rahmati, Mohammad Hossein

2015-02-25

Photocatalytic degradation of Congo red was investigated using ZnO-CdS core-shell nano-structure coated on glass by Doctor Blade method in aqueous solution under irradiation. Field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques were used for the morphological and structural characterization of ZnO-CdS core-shell nanostructures. XRD results showed diffractions of wurtzite zinc oxide core and wurtzite cadmium sulfide shell. FESEM results showed that nanoparticles are nearly hexagonal with an average diameter of about 50 nm. The effect of catalyst loading, UV-light irradiation time and solution pH on photocatalytic degradation of Congo red was studied and optimized values were obtained. Results showed that the employment of efficient photocatalyst and selection of optimal operational parameters may lead to complete decolorization of dye solutions. It was found that ZnO-CdS core-shell nano-structure is more favorable for the degradation of Congo red compare to pure ZnO or pure CdS due to lower electron hole recombination. The results showed that the photocatalytic degradation rate of Congo red is enhanced with increasing the content of ZnO up to ZnO(0.2 M)/CdS(0.075 M) which is reached 88.0% within 100 min irradiation. Copyright © 2014 Elsevier B.V. All rights reserved.

Intracellular zinc distribution in mitochondria, ER and the Golgi apparatus

PubMed Central

Lu, Qiping; Haragopal, Hariprakash; Slepchenko, Kira G; Stork, Christian; Li, Yang V

2016-01-01

Zinc (Zn2+) is required for numerous cellular functions. As such, the homeostasis and distribution of intracellular zinc can influence cellular metabolism and signaling. However, the exact distribution of free zinc within live cells remains elusive. Previously we showed the release of zinc from thapsigargin/IP3-sensitive endoplasmic reticulum (ER) storage in cortical neurons. In the present study, we investigated if other cellular organelles also contain free chelatable zinc and function as organelle storage for zinc. To identify free zinc within the organelles, live cells were co-stained with Zinpyr-1, a zinc fluorescent dye, and organelle-specific fluorescent dyes (MitoFluor Red 589: mitochondria; ER Tracker Red: endoplasmic reticulum; BODIPY TR ceramide: Golgi apparatus; Syto Red 64: nucleus). We examined organelles that represent potential storing sites for intracellular zinc. We showed that zinc fluorescence staining was co-localized with MitoFluor Red 589, ER Tracker Red, and BODIPY TR ceramide respectively, suggesting the presence of free zinc in mitochondria, endoplasmic reticulum, and the Golgi apparatus. On the other hand, cytosol and nucleus had nearly no detectable zinc fluorescence. It is known that nucleus contains high amount of zinc binding proteins that have high zinc binding affinity. The absence of zinc fluorescence suggests that there is little free zinc in these two regions. It also indicates that the zinc fluorescence detected in mitochondria, ER and Golgi apparatus represents free chelatable zinc. Taken together, our results support that these organelles are potential zinc storing organelles during cellular zinc homeostasis. PMID:27186321

A red orange extract modulates the vascular response to a recreational dive: a pilot study on the effect of anthocyanins on the physiological consequences of scuba diving.

PubMed

Balestra, C; Cimino, F; Theunissen, S; Snoeck, T; Provyn, S; Canali, R; Bonina, A; Virgili, F

2016-09-01

Nutritional antioxidants have been proposed as an expedient strategy to counter the potentially deleterious effects of scuba diving on endothelial function, flow-mediated dilation (FMD) and heart function. Sixteen volunteers performing a single standard dive (20 min at 33 m) according to US Navy diving procedures were randomly assigned to two groups: one was administered with two doses of 200 mg of an anthocyanins (AC)-rich extract from red oranges, 12 and 4 h before diving. Anthocyanins supplementation significantly modulated the effects of diving on haematocrit, body water distribution and FMD. AC administration significantly reduces the potentially harmful endothelial effects of a recreational single dive. The lack of any significant effect on the most common markers of plasma antioxidant capacity suggests that the mechanism underlying this protective activity is independent of the putative antioxidant effect of AC and possibly involves cellular signalling modulation of the response to high oxygen.

Solvatochromic and Fluorogenic Dyes as Environment-Sensitive Probes: Design and Biological Applications.

PubMed

Klymchenko, Andrey S

2017-02-21

Fluorescent environment-sensitive probes are specially designed dyes that change their fluorescence intensity (fluorogenic dyes) or color (e.g., solvatochromic dyes) in response to change in their microenvironment polarity, viscosity, and molecular order. The studies of the past decade, including those of our group, have shown that these molecules become universal tools in fluorescence sensing and imaging. In fact, any biomolecular interaction or change in biomolecular organization results in modification of the local microenvironment, which can be directly monitored by these types of probes. In this Account, the main examples of environment-sensitive probes are summarized according to their design concepts. Solvatochromic dyes constitute a large class of environment-sensitive probes which change their color in response to polarity. Generally, they are push-pull dyes undergoing intramolecular charge transfer. Emission of their highly polarized excited state shifts to the red in more polar solvents. Excited-state intramolecular proton transfer is the second key concept to design efficient solvatochromic dyes, which respond to the microenvironment by changing relative intensity of the two emissive tautomeric forms. Due to their sensitivity to polarity and hydration, solvatochromic dyes have been successfully applied to biological membranes for studying lipid domains (rafts), apoptosis and endocytosis. As fluorescent labels, solvatochromic dyes can detect practically any type of biomolecular interactions, involving proteins, nucleic acids and biomembranes, because the binding event excludes local water molecules from the interaction site. On the other hand, fluorogenic probes usually exploit intramolecular rotation (conformation change) as a design concept, with molecular rotors being main representatives. These probes were particularly efficient for imaging viscosity and lipid order in biomembranes as well as to light up biomolecular targets, such as antibodies, aptamers and receptors. The emerging concepts to achieve fluorogenic response to the microenvironment include ground-state isomerization, aggregation-caused quenching, and aggregation-induced emission. The ground-state isomerization exploits, for instance, polarity-dependent spiro-lactone formation in silica-rhodamines. The aggregation-caused quenching uses disruption of the self-quenched dimers and nanoassemblies of dyes in less polar environments of lipid membranes and biomolecules. The aggregation-induced emission couples target recognition with formation of highly fluorescent dye aggregates. Overall, solvatochromic and fluorogenic probes enable background-free bioimaging in wash-free conditions as well as quantitative analysis when combined with advanced microscopy, such as fluorescence lifetime (FLIM) and ratiometric imaging. Further development of fluorescent environment-sensitive probes should address some remaining problems: (i) improving their optical properties, especially brightness, photostability, and far-red to near-infrared operating range; (ii) minimizing nonspecific interactions of the probes in biological systems; (iii) their adaptation for advanced microscopies, notably for superresolution and in vivo imaging.

Congo Red Stain Identifies Matrix Overproduction and Is an Indirect Measurement for c-di-GMP in Many Species of Bacteria.

PubMed

Jones, Christopher J; Wozniak, Daniel J

2017-01-01

Congo red is a diazo textile dye that has been used to visualize the production of amyloid fibers for nearly a century. Microbiological applications were later developed, especially in identifying strains that produce amyloid appendages called curli and overexpressing polysaccharides in the biofilm matrix. The second messenger cyclic diguanylate (c-di-GMP) regulates the production of biofilm matrix polysaccharides, and therefore Congo red staining of samples can be utilized as an indirect measurement of elevated c-di-GMP production in bacteria. Congo red allows the identification of strains producing high c-di-GMP in an inexpensive, quantitative, and high-throughput manner.

Preparation of demipermanent and semipermanent hair dyes gels from ethanol extract of Caesalpinia sappan L. using carbomer as gelling agent

NASA Astrophysics Data System (ADS)

Indrawati, T.; Syahrin, A.; Irpan

2017-07-01

Caesalpinia sappan L. (Cs L) contains of essential oils, saponin, brazilin, brazilein, alkaloids, flavonoids and tannins that have a function as cationic natural dyes. The aim of this research was to prepare the ethanol extract of Cs L wood and to prepare demi-permanent and semi-permanent of hair dye gels by using Carbomer of 2 % and 1.5 % as gelling agent and Cs L extract as cationic dyes. The Extract of Cs L was macerated by using ethanol of 96 % as the solvent, and then thickened. Three formula of demi-permanent hair dye gels were made by using Cs L extract of 3 %, 6% and 9 %. Three formula of semi-permanent hair dye gels were made by using Cs L extract of 2.50 %, 7.00 % and 10.50 %. Those hair dyes gels were prepared by swelling and mixing methods. All products of hair dyes gels were evaluated with organoleptic test, homogeneity test, pH test, consistency test, rheological properties test and dyeing effect test. The demi-permanent hair dye gels products had brown to brown dark black colors, pH of 5.05-5.43, homogeny, specific Cs L odor, and had pseudoplastic thixotropic flow characteristic. The semi-permanent hair dye gels products had red color pH of 6.5-6.25, homogeny, Cs L odor, and have pseudoplastic thixotropic flow characteristics. The optimum formula of demi-permanent was formula gel that contained of 6 % extract of Cs L and the optimum formula of permanent hair dyes gel was formula that contained of 10.50 % extract of Cs L.

Analysis of cytotoxicity and genotoxicity on E. coli, human blood cells and Allium cepa suggests a greater toxic potential of hair dye.

PubMed

Maiti, Swati; Sasmal, Kankaayan; Sinha, Sudarson Sekhar; Singh, Mukesh

2016-02-01

Pharmaceuticals and personal care products (PPCPs) are among the most important emerging environmental contaminants in recent time. PPCPs include wide range of cosmetics, among which hair dyes, are immensely popular in modern society. However, impact of hair dye and its residual discharged to the environment in relation to human health and ecological imbalance have not been widely studied. Based on the result of initial survey among the group of populations of eastern India, three most popular and commonly used permanent hair dyes are selected. Working sample of dye is prepared as recommended on the instructions booklet of the hair dye. The effect of three dyes is studied on Escherichia coli, human red blood cells (RBC), white blood cells (WBC) and Allium cepa bulbs by growth inhibition, hemolysis, 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay and A. cepa micronuclei assays respectively. The Lethal dose (LD) demonstrated significant differences among three dyes and the model systems. In vitro hemolytic assays performed on RBC, and MTT assays on WBC show the cytotoxic effects of hair dye. Significant growth inhibition of E. coli has also been noted. In addition, the root tips of A. cepa treated with the dye have shown major chromosomal abnormalities coupled with cell division retardation. Here low mitotic index confirm cell division retardation. Finally, results of in vitro studies of dye-DNA interactions demonstrate electrostatic interaction. Combing all these results it confirms that hair dyes are cytotoxic and may cause mutagenic effect on living cells irrespective of microbes, plant and animal system. Copyright © 2015 Elsevier Inc. All rights reserved.

Amelioration of oxidative stress in bio-membranes and macromolecules by non-toxic dye from Morinda tinctoria (Roxb.) roots.

PubMed

Bhakta, Dipita; Siva, Ramamoorthy

2012-06-01

Plant dyes have been in use for coloring and varied purposes since prehistoric times. A red dye found in the roots of plants belonging to genus Morinda is a well recognized coloring ingredient. The dye fraction obtained from the methanolic extract of the roots of Morinda tinctoria was explored for its role in attenuating damages caused by H(2)O(2)-induced oxidative stress. The antioxidant potential of the dye fraction was assessed through DPPH radical scavenging, deoxyribose degradation and inhibition of lipid peroxidation in mice liver. It was subsequently screened for its efficiency in extenuating damage incurred to biomembrane (using erythrocytes and their ghost membranes) and macromolecules (pBR322 DNA, lipids and proteins) from exposure to hydrogen peroxide. In addition, the non-toxic nature of the dye was supported by the histological evaluation conducted on the tissue sections from the major organs of Swiss Albino mice as well as effect on Hep3B cell line (human hepatic carcinoma). The LC-MS confirms the dye fraction to be morindone. Our study strongly suggests that morindone present in the root extracts of M. tinctoria, in addition to being a colorant, definitely holds promise in the pharmaceutical industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mediator-assisted decolorization and detoxification of textile dyes/dye mixture by Cyathus bulleri laccase.

PubMed

Chhabra, Meenu; Mishra, Saroj; Sreekrishnan, T R

2008-12-01

Laccase from basidiomycete fungus Cyathus bulleri was evaluated for its ability to decolorize a number of reactive and acidic dyes in the presence of natural and synthetic mediators. The extent of decolorization was monitored at different mediator/dye concentrations and incubation time. Among the synthetic mediators, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) was effective at low mediator/dye ratios and resulted in 80-95% decolorization at rates that varied from 226 +/- 4 nmol min(-1) mg(-1) for Reactive Orange 1 to 1,333 +/- 15 nmol min(-1) mg(-1) for Reactive Red 198. Other synthetic mediators like 1-hydroxybenzotriazole and violuric acid showed both concentration- and time-dependent increases in percent decolorization. Natural mediators like vanillin, on the other hand, were found to be less effective on all the dyes except Reactive Orange 1. Computed rates of decolorization were about twofold lower than that with ABTS. The laccase-ABTS system also led to nearly 80% decolorization for the simulated dye mixture. No clear correlation between laccase activity on the mediator and its ability to decolorize dyes was found, but pH had a significant effect: Optimum pH for decolorization coincided with the optimum pH for mediator oxidation. The treated samples were also evaluated for toxicity in model microbial systems. The laccase-mediator system appears promising for treatment of textile wastewaters.

Study of decolorisation of binary dye mixture by response surface methodology.

PubMed

Khamparia, Shraddha; Jaspal, Dipika

2017-10-01

Decolorisation of a complex mixture of two different classes of textile dyes Direct Red 81 (DR81) and Rhodamine B (RHB), simulating one of the most important condition in real textile effluent was investigated onto deoiled Argemone Mexicana seeds (A. Mexicana). The adsorption behaviour of DR81 and RHB dyes was simultaneously analyzed in the mixture using derivative spectrophotometric method. Central composite design (CCD) was employed for designing the experiments for this complex binary mixture where significance of important parameters and possible interactions were analyzed by response surface methodology (RSM). Maximum adsorption of DR81 and RHB by A. Mexicana was obtained at 53 °C after 63.33 min with 0.1 g of adsorbent and 8 × 10 -6  M DR81, 12 × 10 -6  M RHB with composite desirability of 0.99. The predicted values for percentage removal of dyes from the mixture were in good agreement with the experimental values with R 2 > 96% for both the dyes. CCD superimposed RSM confirmed that presence of different dyes in a solution created a competition for the adsorbent sites and hence interaction of dyes was one of the most important factor to be studied to simulate the real effluent. The adsorbent showed remarkable adsorption capacities for both the dyes in the mixture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dye surface coating enables visible light activation of TiO2 nanoparticles leading to degradation of neighboring biological structures.

PubMed

Blatnik, Jay; Luebke, Lanette; Simonet, Stephanie; Nelson, Megan; Price, Race; Leek, Rachael; Zeng, Leyong; Wu, Aiguo; Brown, Eric

2012-02-01

Biologically and chemically modified nanoparticles are gaining much attention as a new tool in cancer detection and treatment. Herein, we demonstrate that an alizarin red S (ARS) dye coating on TiO2 nanoparticles enables visible light activation of the nanoparticles leading to degradation of neighboring biological structures through localized production of reactive oxygen species. Successful coating of nanoparticles with dye is demonstrated through sedimentation, spectrophotometry, and gel electrophoresis techniques. Using gel electrophoresis, we demonstrate that visible light activation of dye-TiO2 nanoparticles leads to degradation of plasmid DNA in vitro. Alterations in integrity and distribution of nuclear membrane associated proteins were detected via fluorescence confocal microscopy in HeLa cells exposed to perinuclear localized ARS-TiO2 nanoparticles that were photoactivated with visible light. This study expands upon previous studies that indicated dye coatings on TiO2 nanoparticles can serve to enhance imaging, by clearly showing that dye coatings on TiO2 nanoparticles can also enhance the photoreactivity of TiO2 nanoparticles by allowing visible light activation. The findings of our study suggest a therapeutic application of dye-coated TiO2 nanoparticles in cancer research; however, at the same time they may reveal limitations on the use of dye assisted visualization of TiO2 nanoparticles in live-cell imaging.

Acid-base treated vermiculite as high performance adsorbent: Insights into the mechanism of cationic dyes adsorption, regeneration, recyclability and stability studies.

PubMed

Stawiński, Wojciech; Węgrzyn, Agnieszka; Dańko, Tomasz; Freitas, Olga; Figueiredo, Sónia; Chmielarz, Lucjan

2017-04-01

Additional treatment with NaOH of acid activated vermiculite results in even higher increase in the adsorption capacity in comparison to samples modified only in acidic solution (first step of activation) with respect to raw material. Optimization of treatment conditions and adsorption capacity for two cationic dyes (methylene blue (MB) and astrazon red (AR)), also as binary mixture, was evaluated. The capacity, based on column studies, increased from 48 ± 2 to 203 ± 4 mg g -1 in the case of methylene blue and from 51 ± 1 to 127 ± 2 mg g -1 in the case of astrazon red on starting and acid-base treated material, respectively. It was shown that adsorption mechanism changes for both cationic dyes after NaOH treatment and it results in decrease of adsorption rate. In binary mixtures methylene blue is bound stronger by adsorbent and astrazon red may be removed in initial stage of adsorption. Extensive studies on desorption/regeneration process proved high efficiency in recyclable use of all materials. Although cation exchange capacity decreases due to acid treatment, after base treatment exchange properties are used more efficiently. On the other hand, increased specific surface area has less significant contribution into the adsorption potential of studied materials. Obtained adsorbents worked efficiently in 7 adsorption-regeneration cycles and loss of adsorption capacity was observed only in two first cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

Photocatalytic removal of Congo red dye using MCM-48/Ni2O3 composite synthesized based on silica gel extracted from rice husk ash; fabrication and application.

PubMed

Shaban, Mohamed; Abukhadra, Mostafa R; Hamd, Ahmed; Amin, Ragab R; Abdel Khalek, Ahmed

2017-12-15

MCM-48 mesoporous silica was successfully synthesized from silica gel extracted from rice husk ash and loaded by nickel oxide (Ni 2 O 3 ). The resulted composite was characterized using X-ray diffraction, scanning electron microscope, and UV-vis spectrophotometer. The role of MCM-48 as catalyst support in enhancing the photocatalytic properties of nickel oxide was evaluated through the photocatalytic degradation of Congo red dye under visible light source. MCM-48 as catalyst support for Ni 2 O 3 shows considerable enhancement in the adsorption capacity by 17% and 29% higher than the adsorption capacity of MCM-48 and Ni 2 O 3 , respectively. Additionally, the photocatalytic degradation percentage increased by about 64% relative to the degradation percentage using Ni 2 O 3 as a single component. The adsorption mechanism of MCM-48/Ni 2 O 3 is chemisorption process of multilayer form. The using of MCM-48 as catalyst support for Ni 2 O 3 enhanced the adsorption capacity and the photocatalytic degradation through increasing the surface area and prevents the nickel oxide particles from agglomeration. This was done through fixing nickel oxide particles throughout the porous structure which providing more exposed active adsorption sites and active photocatalyst sites for the incident photons. Based on the obtained results, supporting of nickel oxide particles onto MCM-48 are promising active centers for the degradation of Congo red dye molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

High-repetition-rate, narrow-band dye lasers with water as a solvent for dyes

NASA Astrophysics Data System (ADS)

Ray, Alok K.; Sinha, Sucharita; Kundu, Soumitra; Kumar, Sasi; Nair, Sivagiriyal Karunakaran Sreenivasan; Pal, Tamal; Dasgupta, Kamalesh

2002-03-01

The performance of a copper vapor laser-pumped narrow-band dye laser in oscillator-amplifier configuration with water-based binary mixture solvents is described. Although oscillator efficiency in water-surfactant (sodium lauryl sulfate) solvent was comparable with that that employed pure ethanolic solvent, amplifier efficiency was found to be lower. Experiments that were carried out with vertically polarized pump beams and either horizontally or vertically polarized signal beams show that, in case of both the pump and signal having orthogonal polarization (horizontal) and same polarization (vertical), the extraction efficiency for both ethanolic and water-micelle media increased substantially from 15.7% to 18.5% and from 10% to 12.5%, respectively. However, the relative difference remained nearly the same, indicating that a slower orientational diffusion of excited dye molecules in a micellar medium is not responsible for a decrease in amplifier efficiency. Amplifier efficiency comparable with that containing ethanolic dye solutions could be obtained with a binary solvent that comprises a mixture of water and about 30% n-propanol. The performances of two efficient dyes, Rhodamine-6G and Kiton Red S, using water-based solvents were studied.

Physical and chemical investigations on natural dyes

NASA Astrophysics Data System (ADS)

Acquaviva, S.; D'Anna, E.; de Giorgi, M. L.; Della Patria, A.; Baraldi, P.

2010-09-01

Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting. In this work, physical and chemical properties of four selected dyes, namely red (Madder), yellow (Weld and Turmeric) and blue (Woad) colours, produced by means of traditional techniques at the Museo dei Colori Naturali (Lamoli, Italy), have been investigated. The chromatic properties have been studied through the reflectance spectroscopy, a non-invasive technique for the characterisation of chromaticity. Reflection spectra both from powders and egg-yolk tempera models have been acquired to provide the typical features of the dyes in the UV-vis spectral range. Moreover, to assess the feasibility of laser cleaning procedures, tempera layers were investigated after irradiation with an excimer laser. Micro Raman spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray analyses have complemented the survey, returning compositional and morphological information as well. Efforts have been made to give scientific feedback to the production processes and to support the research activity in the restoration of the artworks where these dyes were employed.

Dye-Enhanced Self-Electrophoretic Propulsion of Light-Driven TiO2-Au Janus Micromotors

NASA Astrophysics Data System (ADS)

Wu, Yefei; Dong, Renfeng; Zhang, Qilu; Ren, Biye

2017-07-01

Light-driven synthetic micro-/nanomotors have attracted considerable attention in recent years due to their unique performances and potential applications. We herein demonstrate the dye-enhanced self-electrophoretic propulsion of light-driven TiO2-Au Janus micromotors in aqueous dye solutions. Compared to the velocities of these micromotors in pure water, 1.7, 1.5, and 1.4 times accelerated motions were observed for them in aqueous solutions of methyl blue (10-5 g L-1), cresol red (10-4 g L-1), and methyl orange (10-4 g L-1), respectively. We determined that the micromotor speed changes depending on the type of dyes, due to variations in their photodegradation rates. In addition, following the deposition of a paramagnetic Ni layer between the Au and TiO2 layers, the micromotor can be precisely navigated under an external magnetic field. Such magnetic micromotors not only facilitate the recycling of micromotors, but also allow reusability in the context of dye detection and degradation. In general, such photocatalytic micro-/nanomotors provide considerable potential for the rapid detection and "on-the-fly" degradation of dye pollutants in aqueous environments.

Sono- and photocatalytic activities of SnO2 nanoparticles for degradation of cationic and anionic dyes

NASA Astrophysics Data System (ADS)

Paramarta, Valentinus; Taufik, Ardiansyah; Munisa, Lusitra; Saleh, Rosari

2017-01-01

The current research work focuses on the catalytic activity of SnO2 nanoparticles (NPs) against degradation of both cationic dye (methylene blue) and anionic dye (Congo-red). SnO2 NPs were synthesized under the sol-gel method and were characterized by performing X-ray diffraction, Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM) Brunauer-Emmet-Teller (BET) surface area analysis and UV-Vis spectroscopy. The results demonstrate that SnO2 NPs has well crystalline structure with the crystallite size of 44 nm. The degradation of dyes was studied under ambient temperature using ultrasonicator and UV light, respectively. The sono- and photocatalytic activities of SnO2 NPs on dyes were analyzed by measuring the change in absorbance of dyes under UV-spectrophotometer. The degradation of the organic dyes has been calculated by monitoring the degradation in the concentration of the dyes before and after irradiation of ultrasonic and light, respectively. The influence of other parameters such as catalyst dosage, pH and scavenger have also been investigated. The catalytic activity is enhanced in the presence of ultrasonic irradiation. The degradation of both dyes follows pseudo-first order kinetics. The reusability tests have also been done to ensure the stability of the used catalysts. A reasonable mechanism of sono- and photocatalysis with SnO2 NPs has been proposed by correlating the active radical species involved with the physical properties of the as-synthesized samples.