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Souza JC, Machini WBS, Zanoni MVB, Oliveira‐Brett AM. Human Hair Keratin Direct Electrochemistry and
In Situ
Interaction with
p
‐Toluenediamine and
p
‐Aminophenol Hair Dye Precursors using a Keratin Electrochemical Biosensor. ChemElectroChem 2020. [DOI: 10.1002/celc.202000151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- João C. Souza
- Department of Chemistry, Faculty of Science and TechnologyUniversity of Coimbra Rua Larga 3004-535 Coimbra Portugal
- Department of Analytical Chemistry, Institute of Chemistry National Institute of Alternative Technologies for Detection Toxicological Assessment and Removal of Micropollutants and Radioactive (INCT-DATREM)São Paulo State University (UNESP) Av. Prof. Francisco Degni, 55 14800-060, Araraquara São Paulo Brazil
| | - Wesley B. S. Machini
- Department of Chemistry, Faculty of Science and TechnologyUniversity of Coimbra Rua Larga 3004-535 Coimbra Portugal
| | - Maria Valnice B. Zanoni
- Department of Analytical Chemistry, Institute of Chemistry National Institute of Alternative Technologies for Detection Toxicological Assessment and Removal of Micropollutants and Radioactive (INCT-DATREM)São Paulo State University (UNESP) Av. Prof. Francisco Degni, 55 14800-060, Araraquara São Paulo Brazil
| | - Ana Maria Oliveira‐Brett
- Department of Chemistry, Faculty of Science and TechnologyUniversity of Coimbra Rua Larga 3004-535 Coimbra Portugal
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Vacchi FI, Vendemiatti JAS, Brosselin V, Ferreira da Silva B, B Zanoni MV, DeMeo M, Bony S, Devaux A, Umbuzeiro GA. Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges. Environ Mol Mutagen 2016; 57:559-71. [PMID: 27412112 DOI: 10.1002/em.22034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/20/2016] [Accepted: 06/22/2016] [Indexed: 05/26/2023]
Abstract
Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg-modified comet assay in the RTL-W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg-modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559-571, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Francine I Vacchi
- Faculty of Pharmaceutical Sciences, USP, São Paulo, Brazil
- School of Technology, UNICAMP, Limeira, São Paulo, Brazil
| | | | - Vanessa Brosselin
- University of Lyon, INRA, UMR LEHNA 5023, ENTPE, FR, Vaulx-en-Velin, France
| | | | | | - Michel DeMeo
- Aix-Marseille University, IMBE, FR, Marseille, France
| | - Sylvie Bony
- University of Lyon, INRA, UMR LEHNA 5023, ENTPE, FR, Vaulx-en-Velin, France
| | - Alain Devaux
- University of Lyon, INRA, UMR LEHNA 5023, ENTPE, FR, Vaulx-en-Velin, France
| | - Gisela A Umbuzeiro
- Faculty of Pharmaceutical Sciences, USP, São Paulo, Brazil
- School of Technology, UNICAMP, Limeira, São Paulo, Brazil
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Zanoni TB, Hudari F, Munnia A, Peluso M, Godschalk RW, Zanoni MVB, den Hartog GJM, Bast A, Barros SBM, Maria-Engler SS, Hageman GJ, de Oliveira DP. The oxidation of p-phenylenediamine, an ingredient used for permanent hair dyeing purposes, leads to the formation of hydroxyl radicals: Oxidative stress and DNA damage in human immortalized keratinocytes. Toxicol Lett 2015; 239:194-204. [PMID: 26456176 DOI: 10.1016/j.toxlet.2015.09.026] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 09/14/2015] [Accepted: 09/29/2015] [Indexed: 02/02/2023]
Abstract
The hair-dyeing ingredient, p-phenylenediamine (PPD), was previously reported to be mutagenic, possibly by inducing oxidative stress. However, the exact mechanism of PPD in inducing oxidative stress upon skin exposure during hair-dyeing in human keratinocytes remains unknown. The aim of our studies was therefore to investigate the toxicity of PPD and its by-products in human immortalized keratinocytes (HaCaT) after auto-oxidation and after reaction with hydrogen peroxide (H2O2). We found that the PPD half maximal effective cytotoxic concentration (EC50) to HaCaT is 39.37 and 35.63 μg/mL after 24 and 48 h, respectively, without addition of H2O2 to induce oxidation. When PPD (10 or 100 μg/mL) is combined with 10.5 μg/mL of H2O2, intracellular ROS production by HaCaT after 1 h was significantly increased and enhanced levels of DNA damage were observed after 4 h of exposure. After 24 h incubations, 20 μg/mL of PPD increased the level of DNA oxidation in HaCaT. Also, we found that the in vitro reaction between PPD and H2O2, even below the maximum allowance by cosmetic industries, released hydroxyl radicals which can damage DNA. Taken together, we conclude that PPD alone and when combined with H2O2 increases the formation of reactive oxygen species in human keratinocytes, leading to oxidative stress and subsequent DNA damage. These alterations suggest that the mechanism by which PPD exposure, alone or combined with H2O2, damages keratinocytes by the formation of the high reactive HO∙ radicals.
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Affiliation(s)
- Thalita B Zanoni
- Department of Environmental Toxicology, School of Pharmaceutical Sciences, University of São Paulo (FCFRP/USP), Av. do Café, s/n, CEP 14040-903 Ribeirão Preto, SP, Brazil.
| | - Felipe Hudari
- Department of Analytical Chemistry, Institute of Chemistry, Univ. Estadual Paulista (UNESP), R. Prof. Francisco Degni, s/n, CEP 14801-970 Araraquara, SP, Brazil
| | - Armelle Munnia
- Cancer Risk Factor Branch, Cancer Prevention Laboratory, ISPO-Cancer Prevention and Research Institute, Via Cosimo il Vecchi 2, 500139 Florence, Italy
| | - Marco Peluso
- Cancer Risk Factor Branch, Cancer Prevention Laboratory, ISPO-Cancer Prevention and Research Institute, Via Cosimo il Vecchi 2, 500139 Florence, Italy
| | - Roger W Godschalk
- Department of Toxicology, Research Institute NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Maria Valnice B Zanoni
- Department of Analytical Chemistry, Institute of Chemistry, Univ. Estadual Paulista (UNESP), R. Prof. Francisco Degni, s/n, CEP 14801-970 Araraquara, SP, Brazil
| | - Gertjan J M den Hartog
- Department of Toxicology, Research Institute NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Aalt Bast
- Department of Toxicology, Research Institute NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Silvia B M Barros
- Department of Clinical Chemistry & Toxicology, School of Pharmaceutical Sciences, University of São Paulo (FCF/USP), Av. Lineu Prestes, 580, CEP 05508-900 São Paulo, Brazil
| | - Silvya S Maria-Engler
- Department of Clinical Chemistry & Toxicology, School of Pharmaceutical Sciences, University of São Paulo (FCF/USP), Av. Lineu Prestes, 580, CEP 05508-900 São Paulo, Brazil
| | - Geja J Hageman
- Department of Toxicology, Research Institute NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Danielle Palma de Oliveira
- Department of Environmental Toxicology, School of Pharmaceutical Sciences, University of São Paulo (FCFRP/USP), Av. do Café, s/n, CEP 14040-903 Ribeirão Preto, SP, Brazil
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Ferraz ERA, Oliveira GAR, Grando MD, Lizier TM, Zanoni MVB, Oliveira DP. Photoelectrocatalysis based on Ti/TiO2 nanotubes removes toxic properties of the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1 from aqueous chloride samples. J Environ Manage 2013; 124:108-14. [PMID: 23624428 DOI: 10.1016/j.jenvman.2013.03.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 02/27/2013] [Accepted: 03/16/2013] [Indexed: 05/15/2023]
Abstract
This work describes the efficiency of photoelectrocatalysis based on Ti/TiO2 nanotubes in the degradation of the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1 and to remove their toxic properties, as an alternative method for the treatment of effluents and water. For this purpose, the discoloration rate, total organic carbon (TOC) removal, and genotoxic, cytotoxic and mutagenic responses were determined, using the comet, micronucleus and cytotoxicity assays in HepG2 cells and the Salmonella mutagenicity assay. In a previous study it was found that the surfactant Emulsogen could contribute to the low mineralization of the dyes (60% after 4 h of treatment), which, in turn, seems to account for the mutagenicity of the products generated. Thus this surfactant was not added to the chloride medium in order to avoid this interference. The photoelectrocatalytic method presented rapid discoloration and the TOC reduction was ≥87% after 240 min of treatment, showing that photoelectrocatalysis is able to mineralize the dyes tested. The method was also efficient in removing the mutagenic activity and cytotoxic effects of these three dyes. Thus it was concluded that photoelectrocatalysis was a promising method for the treatment of aqueous samples.
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Affiliation(s)
- E R A Ferraz
- USP, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903 Ribeirão Preto, SP, Brazil.
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Zanoni TB, Lizier TM, Assis MDD, Zanoni MVB, de Oliveira DP. CYP-450 isoenzymes catalyze the generation of hazardous aromatic amines after reaction with the azo dye Sudan III. Food Chem Toxicol 2013; 57:217-26. [PMID: 23562707 DOI: 10.1016/j.fct.2013.03.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/20/2013] [Accepted: 03/24/2013] [Indexed: 10/27/2022]
Abstract
This work describes the mutagenic response of Sudan III, an adulterant food dye, using Salmonella typhimurium assay and the generation of hazardous aromatic amines after different oxidation methods of this azo dye. For that, we used metabolic activation by S9, catalytic oxidation by ironporphyrin and electrochemistry oxidation in order to simulate endogenous oxidation conditions. The oxidation reactions promoted discoloration from 65% to 95% of Sudan III at 1 × 10(-4)molL(-1) and generation of 7.6 × 10(-7)molL(-1) to 0.31 × 10(-4)molL(-1) of aniline, o-anisidine, 2-methoxi-5-methylaniline, 4-aminobiphenyl, 4,4'-oxydianiline; 4,4'-diaminodiphenylmethane and 2,6-dimethylaniline. The results were confirmed by LC-MS-MS experiments. We also correlate the mutagenic effects of Sudan III using S. typhimurium with the strain TA1535 in the presence of exogenous metabolic activation (S9) with the metabolization products of this compound. Our findings clearly indicate that aromatic amines are formed due to oxidative reactions that can be promoted by hepatic cells, after the ingestion of Sudan III. Considering that, the use of azo compounds as food dyestuffs should be carefully controlled.
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Affiliation(s)
- Thalita Boldrin Zanoni
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Universidade de São Paulo, Avenida do Café, s/n, 14040-903 Ribeirão Preto, SP, Brazil
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Guaraldo TT, Zanoni TB, de Torresi SIC, Gonçales VR, Zocolo GJ, Oliveira DP, Zanoni MVB. On the application of nanostructured electrodes prepared by Ti/TiO2/WO3 "template": a case study of removing toxicity of indigo using visible irradiation. Chemosphere 2013; 91:586-593. [PMID: 23332877 DOI: 10.1016/j.chemosphere.2012.12.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2012] [Revised: 12/05/2012] [Accepted: 12/06/2012] [Indexed: 06/01/2023]
Abstract
New assays with HepG2 cells indicate that Indigo Carmine (IC), a dye that is widely used as additive in many food and pharmaceutical industries exhibited cytotoxic effects. This work describes the development of a bicomponent nanostructured Ti/TiO2/WO3 electrode prepared by "template" method and investigates its efficiency in a photoelectrocatalytic method by using visible light irradiation and applied potential of 1V. After 2h of treatment there are reduction of 97% discoloration, 62% of mineralization and formation of three byproducts assigned as: 2-amine-5-sulfo-benzoic acid, 2,3-dioxo-14-indole-5-sulfonic acid, and 2-amino-α-oxo-5-sulfo-benzeneacetic acid were identified by HPLC-MS/MS. But, cytotoxicity was completely removed after 120 min of treatment.
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Affiliation(s)
- Thais T Guaraldo
- UNESP, Instituto de Química, Universidade Estadual Paulista Júlio de Mesquita Filho, Rua Professor Francisco Degni 55, Araraquara, SP, Brazil
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Bergamini MF, Santos DP, Zanoni MVB. Electrochemical behavior and voltammetric determination of pyrazinamide using a poly-histidine modified electrode. J Electroanal Chem (Lausanne) 2013. [DOI: 10.1016/j.jelechem.2012.11.032] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Barros VP, Zanoni MVB, Assis MDD. Characterization of electrodes chemically modified with Mn(III) porphyrin/polypyrrole films as catalytic surfaces for an azo dye. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424606000296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this study we describe the electrochemical behavior of 5,10,15,20-tetrakis(2'-aminophenylporphyrin)manganese(III) chloride supported on a glassy carbon electrode, as well as the electrochemical preparation and characterization of thin films based on pyrrole-3-carboxylic acid. The electrocatalytic action of the electrode modified with the Mn(III) porphyrin toward an azo dye was tested, and the characteristic strong interaction between the incorporated metalloporphyrin and RR120 dye was verified.
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Affiliation(s)
- Valéria P. Barros
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto-SP 14040-901, Brasil
| | - Maria Valnice B. Zanoni
- Departamento de Química Analítica, Instituto de Química, Universidade Estadual Paulista, Caixa Postal 355, Araraquara-SP 14800-900, Brasil
| | - Marilda das D. Assis
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto-SP 14040-901, Brasil
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Ferraz ERA, Umbuzeiro GA, de-Almeida G, Caloto-Oliveira A, Chequer FMD, Zanoni MVB, Dorta DJ, Oliveira DP. Differential toxicity of Disperse Red 1 and Disperse Red 13 in the Ames test, HepG2 cytotoxicity assay, and Daphnia acute toxicity test. Environ Toxicol 2011; 26:489-497. [PMID: 20549607 DOI: 10.1002/tox.20576] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 01/22/2010] [Accepted: 01/26/2010] [Indexed: 05/29/2023]
Abstract
Azo dyes are of environmental concern due to their degradation products, widespread use, and low-removal rate during conventional treatment. Their toxic properties are related to the nature and position of the substituents with respect to the aromatic rings and amino nitrogen atom. The dyes Disperse Red 1 and Disperse Red 13 were tested for Salmonella mutagenicity, cell viability by annexin V, and propidium iodide in HepG2 and by aquatic toxicity assays using daphnids. Both dyes tested positive in the Salmonella assay, and the suggestion was made that these compounds induce mainly frame-shift mutations and that the enzymes nitroreductase and O-acetyltransferase play an important role in the observed effect. In addition, it was shown that the presence of the chlorine substituent in Disperse Red 13 decreased the mutagenicity about 14 times when compared with Disperse Red 1, which shows the same structure as Disperse Red 13, but without the chlorine substituent. The presence of this substituent did not cause cytotoxicity in HepG2 cells, but toxicity to the water flea Daphnia similis increased in the presence of the chlorine substituent. These data suggest that the insertion of a chlorine substituent could be an alternative in the design of dyes with low-mutagenic potency, although the ecotoxicity should be carefully evaluated.
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Affiliation(s)
- E R A Ferraz
- USP, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmaceuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903 Ribeirão Preto, SP, Brazil
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Fraga LE, Zanoni MVB. Nanoporous of W/WO3 Thin Film Electrode Grown by Electrochemical Anodization Applied in the Photoelectrocatalytic Oxidation of the Basic Red 51 used in Hair Dye. J BRAZIL CHEM SOC 2011. [DOI: 10.1590/s0103-50532011000400015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Silva MRA, Vilegas W, Zanoni MVB, Pupo Nogueira RF. Photo-Fenton degradation of the herbicide tebuthiuron under solar irradiation: iron complexation and initial intermediates. Water Res 2010; 44:3745-3753. [PMID: 20537676 DOI: 10.1016/j.watres.2010.04.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/20/2010] [Accepted: 04/22/2010] [Indexed: 05/29/2023]
Abstract
The complexation of iron ions with the herbicide tebuthiuron (TBH), during a solar photo-Fenton process, was investigated using cyclic voltammetry with a glassy carbon electrode. An oxidation peak was observed at +0.64 V after addition of Fe(NO(3))(3) to TBH solution, indicating the formation of a Fe-TBH complex, which was not observed in the presence of ferrioxalate or citrate complexes. This complexation hinders photoreduction of Fe(III), and consequently TBH degradation. The main degradation route, in the presence or absence of citric acid (in the latter case with Fe(NO(3))(3) only), is initiated by the hydroxylation of a terminal methyl group of the urea, indicating an identical degradation mechanism. Hydroxylation of the central methyl of urea, and of the tert-butyl group, was also observed after extended irradiation periods in the presence of citric acid, but was not observed in the presence of Fe(NO(3))(3), due to a slower degradation rate in the absence of the citrate complex. No intermediate, generated from opening of the thiadiazole ring, was identified under the various different conditions.
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Affiliation(s)
- Milady R A Silva
- Instituto de Química de Araraquara, UNESP -Univ Estadual Paulista, CP 355, 14801-970 Araraquara, SP, Brazil
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Carneiro PA, Umbuzeiro GA, Oliveira DP, Zanoni MVB. Assessment of water contamination caused by a mutagenic textile effluent/dyehouse effluent bearing disperse dyes. J Hazard Mater 2010; 174:694-9. [PMID: 19853375 DOI: 10.1016/j.jhazmat.2009.09.106] [Citation(s) in RCA: 190] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Revised: 09/18/2009] [Accepted: 09/21/2009] [Indexed: 05/16/2023]
Abstract
High performance liquid chromatography coupled to a diode array detector method was developed to detect disperse dyes in water samples over the range 0.50-35 ng, with detection limits of 0.09 ng, 0.84 ng and 0.08 ng, respectively, with good repeatability and accuracy. This study identifies the disperse azo dyes C.I. Disperse Blue 373, C.I. Disperse Orange 37 and Disperse Violet 93 as components of a commercial dye formulation assigned as Dispersol Black Dye (CVS) used in the textile industry for dyeing synthetic fibers that are contributing to the mutagenicity found in the Cristais River, São Paulo, Brazil. High performance liquid chromatography coupled to a diode array detector was applied to monitor the occurrence of these dyes in: (1) the treated industrial effluent, (2) raw river water, (3) treated river water, and (4) the sludge produced by a Drinking Water Treatment Plant (DWTP) which is located 6 km downstream from the textile industrial discharge, where dyes' concentrations changed from 1.65 ng L(-1) to 316 microL(-1).
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Affiliation(s)
- Patricia A Carneiro
- Instituto de Química - University of São Paulo State - UNESP, 14800-900 Araraquara, SP, Brazil
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Bergamini MF, Santos DP, Zanoni MVB. Determination of isoniazid in human urine using screen-printed carbon electrode modified with poly-l-histidine. Bioelectrochemistry 2010; 77:133-8. [DOI: 10.1016/j.bioelechem.2009.07.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 07/21/2009] [Accepted: 07/22/2009] [Indexed: 11/27/2022]
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Paschoal FMM, Anderson MA, Zanoni MVB. Simultaneous removal of chromium and leather dye from simulated tannery effluent by photoelectrochemistry. J Hazard Mater 2009; 166:531-537. [PMID: 19168284 DOI: 10.1016/j.jhazmat.2008.11.058] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 11/18/2008] [Accepted: 11/19/2008] [Indexed: 05/27/2023]
Abstract
The feasibility of the photobleaching of a leather acid dye, acid red 151, simultaneously to degradation of anionic surfactant, Tamol, and reduction of Cr(VI) to the less toxic Cr(III) was investigated by photoelectrocatalytic oxidation. The best experimental conditions were found to be pH 2.0 and 0.1 mol L(-1) sodium sulfate when the nanoporous Ti/TiO2 photo anode was biased at +1.0 V and submitted to UV-irradiation. The photoelectrocatalytic oxidation promotes 100% discoloration, reducing around 98-100% of Cr(VI) and achieving an abatement of 95% of the original total organic carbon. The effect of pH, the applied potential, the Cr(VI) concentration and the complexation reaction between Cr(VI) and acid red dye were evaluated as to their effect on the kinetics of the reaction.
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Affiliation(s)
- Fabiana Maria Monteiro Paschoal
- Departamento de Química Analítica, Instituto de Química, Universidade Estadual Paulista, Av. Prof. Francisco degni, s/n, C. P. 355 14801-970 Araraquara, SP, Brazil
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Osugi ME, Rajeshwar K, Ferraz ER, de Oliveira DP, Araújo ÂR, Zanoni MVB. Comparison of oxidation efficiency of disperse dyes by chemical and photoelectrocatalytic chlorination and removal of mutagenic activity. Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2008.07.015] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Fraga LE, Anderson MA, Beatriz ML, Paschoal FM, Romão LP, Zanoni MVB. Evaluation of the photoelectrocatalytic method for oxidizing chloride and simultaneous removal of microcystin toxins in surface waters. Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2008.08.060] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Bergamini MF, Santos DP, Zanoni MVB. Screen-printed carbon electrode modified with poly-L-histidine applied to gold(III) determination. J BRAZIL CHEM SOC 2009. [DOI: 10.1590/s0103-50532009000100017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Brunelli TFT, Guaraldo TT, Paschoal FMM, Zanoni MVB. Degradação fotoeletroquímica de corantes dispersos em efluente têxtil utilizando fotoanodos de Ti/TiO2. QUIM NOVA 2009. [DOI: 10.1590/s0100-40422009000100013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Santos DP, Bergamini MF, Santos VAFFM, Furlan M, Zanoni MVB. Preconcentration of Rutin at a Poly Glutamic Acid Modified Electrode and its Determination by Square Wave Voltammetry. ANAL LETT 2008. [DOI: 10.1080/00032710701689107] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Daniela P. Santos
- a Instituto of Chemistry—University of São Paulo State, UNESP , Araraquara, SP, Brazil
| | - Márcio F. Bergamini
- a Instituto of Chemistry—University of São Paulo State, UNESP , Araraquara, SP, Brazil
| | | | - Maysa Furlan
- a Instituto of Chemistry—University of São Paulo State, UNESP , Araraquara, SP, Brazil
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21
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Bergamini MF, Santos AL, Stradiotto NR, Zanoni MVB. Flow injection amperometric determination of procaine in pharmaceutical formulation using a screen-printed carbon electrode. J Pharm Biomed Anal 2007; 43:315-9. [PMID: 16844336 DOI: 10.1016/j.jpba.2006.06.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 11/21/2022]
Abstract
A rapid and simple method for procaine determination was developed by flow injection analysis (FIA) using a screen-printed carbon electrode (SPCE) as amperometric detector. The present method is based on the amine/hydroxylamine oxidation from procaine monitored at 0.80 V on SPCE in sodium acetate solution pH 6.0. Using the best experimental conditions assigned as: pH 6.0, flow rate of 3.8 mL min(-1), sample volume of 100 microL and analytical path of 30 cm it is possible to construct a linear calibration curve from 9.0x10(-6) to 1.0x10(-4) mol L(-1). The relative standard deviation for 5.0x10(-5) mol L(-1) procaine (15 repetitions using the same electrode) is 3.2% and detection limit calculated is 6.0x10(-6) mol L(-1). Recoveries obtained for procaine gave a mean values from 94.8 to 102.3% and an analytical frequency of 36 injections per hour was achieved. The method was successfully applied for the determination of procaine in pharmaceutical formulation without any pre-treatment, which are in good accordance with the declared values of manufacturer and an official method based on spectrophotometric analysis.
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Affiliation(s)
- Márcio F Bergamini
- Departamento de Química Analítica, Instituto de Química, Universidade Estadual Paulista, UNESP, CP 355, CEP 14801-970 Araraquara, SP, Brazil
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22
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Oliveira DP, Carneiro PA, Sakagami MK, Zanoni MVB, Umbuzeiro GA. Chemical characterization of a dye processing plant effluent—Identification of the mutagenic components. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2007; 626:135-42. [PMID: 17070726 DOI: 10.1016/j.mrgentox.2006.09.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 09/25/2006] [Accepted: 09/27/2006] [Indexed: 10/24/2022]
Abstract
This work shows the chemical characterization of a dye processing plant effluent that was contributing to the mutagenicity previously detected in the Cristais river, São Paulo, Brazil, that had an impact on the quality of the related drinking water. The mutagenic dyes Disperse Blue 373, Disperse Orange 37 and Disperse Violet 93, components of a Black Dye Commercial Product (BDCP) frequently used by the facility, were detected by thin layer chromatography (TLC). The blue and orange dyes were quantified by high performance liquid chromatography (HPLC/DAD) in a raw and treated effluent samples and their contribution to the mutagenicity was calculated based on the potency of each dye for the Salmonella YG1041. In the presence of S9 the Disperse Blue 373 accounted for 2.3% of the mutagenic activity of the raw and 71.5% of the treated effluent. In the absence of S9 the Disperse Blue 373 accounted for 1.3% of the mutagenic activity of the raw and 1.5% of the treated effluent. For the Disperse Orange 37, in the presence of S9, it contributed for 0.5% of the mutagenicity of the raw and 6% of the treated effluent. In the absence of S9; 11.5% and 4.4% of the raw and treated effluent mutagenicity, respectively. The contribution of the Disperse Violet 93 was not evaluated because this compound could not be quantified by HPLC/DAD. Mutagenic and/or carcinogenic aromatic amines were also preliminary detected using gas chromatograph/mass spectrometry in both raw and treated and are probably accounting for part of the observed mutagenicity. The effluent treatment applied by the industry does not seem to remove completely the mutagenic compounds. The Salmonella/microsome assay coupled with TLC analysis seems to be an important tool to monitor the efficiency of azo dye processing plant effluent treatments.
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Affiliation(s)
- Danielle P Oliveira
- USP, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903 Ribeirão Preto, SP, Brazil.
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23
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Oliveira DP, Carneiro PA, Rech CM, Zanoni MVB, Claxton LD, Umbuzeiro GA. Mutagenic compounds generated from the chlorination of disperse azo-dyes and their presence in drinking water. Environ Sci Technol 2006; 40:6682-9. [PMID: 17144296 DOI: 10.1021/es061020p] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The water produced by the Cristais River Drinking Water Treatment Plant (CR-DWTP) repeatedly produced mutagenic responses that could not be explained by the presence of disinfection byproducts (DBPs) generated by the reaction of humic acids and chlorine. In order to determine the possible role of chlorinated dye products in this mutagenic activity, solutions of a black dye commercial product (BDCP) composed of C.I. Disperse Blue 373, C.I. Disperse Orange 37, C.I. Disperse Violet 93, and chemically reduced BDCP (R-BDCP) were chlorinated in a manner similar to that used by the CR-DWTP. The resulting solutions were extracted with XAD-4 along with one drinking water sample collected from the CR-DWTP. All extracts showed mutagenic activity in the Salmonella/microsome assay. Dye components of the BDCP as well as its reduced chlorinated (CI-R-BDCP) derivative were detected in the drinking water sample by analysis with a high performance liquid chromatography/diode array detector (HPLC/DAD). The mutagenicity results of these products suggest that they are, at least in part, accounting for the mutagenic activity detected in the drinking water samples from the Cristais River. The data obtained in this study have environmental and health implications because the chlorination of the BDCP and the R-BDCP leads to the formation of mutagenic compounds (CI-BDCP and CI-R-BDCP), which are potentially important disinfection byproducts that can contaminate the drinking water as well as the environment.
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Affiliation(s)
- Danielle P Oliveira
- Faculdade de Ciências Farmaceuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903, Ribeirdo Preto, SP, Brazil.
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24
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Osugi ME, Umbuzeiro GA, De Castro FJV, Zanoni MVB. Photoelectrocatalytic oxidation of remazol turquoise blue and toxicological assessment of its oxidation products. J Hazard Mater 2006; 137:871-7. [PMID: 16697523 DOI: 10.1016/j.jhazmat.2006.03.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2005] [Revised: 03/01/2006] [Accepted: 03/03/2006] [Indexed: 05/09/2023]
Abstract
The ability of photoelectrocatalytic oxidation to degrade the commercially important copper-phtalocyanine dye, remazol turquoise blue 15 (RTB) was investigated. The best experimental condition was optimized, evaluating the performance of Ti/TiO2 thin-film electrodes prepared by sol-gel method in the decolourization of 32 mg L(-1) RTB dye in 0.5 mol L(-1) Na2SO4 pH 8 and applied potential of +1.5 V versus SCE under UV irradiation. Spectrophotometric measurements, high performance liquid chromatography, dissolved organic carbon (TOC) evaluation and stripping analysis of yielding solution obtained after 3 h of photoelectrolysis leads to 100% of absorbance removal from wavelength of 250-800 nm, 79.6% of TOC reduction and the releasing of up to 54.6% dye-bound copper (0.85 mg L(-1)) into the solution. Both, original and oxidized dye solution did not presented mutagenic activity with the strains TA98 and TA100 of Salmonella in the presence and absence of S9 mix at the tested doses. Nevertheless, the yielding photoelectrocatalytic oxidized solution showed an increase in the acute toxicity for Vibrio fischeri bacteria, explained by copper liberation during treatment.
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Affiliation(s)
- Marli E Osugi
- Instituto de Química, UNESP, C.P. 355, 14801-970 Araraquara, SP, Brazil
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Rodgher VS, Stradiotto NR, Zanoni MVB, Barros AA. Eletroanálise de derivados acetaldeído com hidrazina e determinação em amostras de álcool combustível por voltametria de onda quadrada. QUIM NOVA 2006. [DOI: 10.1590/s0100-40422006000400007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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26
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Saczk AA, Okumura LL, De Oliveira MF, Zanoni MVB, Stradiotto NR. Determination of acetaldehyde in fuel ethanol by high-performance liquid chromatography with electrochemical detection. ANAL SCI 2006; 21:441-4. [PMID: 15844343 DOI: 10.2116/analsci.21.441] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The cyclic voltammetric behavior of acetaldehyde and the derivatized product with 2,4-dinitrophenylhydrazine (DNPHi) has been studied at a glassy carbon electrode. This study was used to optimize the best experimental conditions for its determination by high-performance liquid chromatographic (HPLC) separation coupled with electrochemical detection. The acetaldehyde-2,4-dinitrophenylhydrazone (ADNPH) was eluted and separated by a reversed-phase column, C18, under isocratic conditions with the mobile phase containing a binary mixture of methanol/LiCl(aq) at a concentration of 1.0 x 10(-3) M (80:20 v/v) and a flow rate of 1.0 mL min(-1). The optimum condition for the electrochemical detection of ADNPH was +1.0 V vs. Ag/AgCl as a reference electrode. The proposed method was simple, rapid (analysis time 7 min) and sensitive (detection limit 3.80 microg L(-1)) at a signal-to-noise ratio of 3:1. It was also highly selective and reproducible [standard deviation 8.2% +/- 0.36 (n = 5)]. The analytical curve of ADNPH was linear over the range of 3-300 mg L(-1) per injection (20 microL), and the analytical recovery was > 99%.
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Affiliation(s)
- Adelir A Saczk
- UNESP, Department of Analytical Chemistry, Rua Prof Francisco Degni s/n, Quitandinha, 14800-900, Araraquara-SP, Brazil
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27
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Bergamini MF, Santos AL, Stradiotto NR, Zanoni MVB. A disposable electrochemical sensor for the rapid determination of levodopa. J Pharm Biomed Anal 2005; 39:54-9. [PMID: 15896939 DOI: 10.1016/j.jpba.2005.03.014] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 02/17/2005] [Accepted: 03/01/2005] [Indexed: 10/25/2022]
Abstract
Levodopa (L-dopa), the biological precursor of catecholamines, is the most widely prescribed drug in the treatment of Parkinson's disease. The present work presents a proposal for the application of a gold screen-printed electrode an electrochemical sensor for monitoring L-dopa in stationary solution and a flow system. Using the electrooxidation of L-dopa at +0.63 V in acetate buffer pH 3.0 on a gold screen-printed electrode it is possible to obtain a linear calibration curve from 9.9 x 10(-5) to 1.2 x 10(-3) mol L(-1) and a detection limit of 6.8 x 10(-5) mol L(-1). Under amperometric conditions (E(app) = 0.8 V; flow rate = 14.1 mL min(-1); pH 3.0), an analytical calibration graph for l-dopa was obtained from 1.0 x 10(-6) mol L(-1) 6.6 x 10(-4) mol L(-1) with a detection limit of 9.9 x 10(-7) mol L(-1). The method was successfully applied to the determination of L-dopa in commercial dosage forms without any pre-treatment.
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Affiliation(s)
- Márcio F Bergamini
- Departamento de Química Analítica, Instituto de Química, Universidade Estadual Paulista, UNESP, CP 355, Araraquara, SP, Brazil
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Carneiro PA, Osugi ME, Fugivara CS, Boralle N, Furlan M, B Zanoni MV. Evaluation of different electrochemical methods on the oxidation and degradation of Reactive Blue 4 in aqueous solution. Chemosphere 2005; 59:431-439. [PMID: 15763096 DOI: 10.1016/j.chemosphere.2004.10.043] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2003] [Revised: 04/23/2004] [Accepted: 10/20/2004] [Indexed: 05/24/2023]
Abstract
The oxidation of a reactive dye, Reactive Blue 4, RB4, (C.I. 61205), widely used in the textile industries to color natural fibers, was studied by electrochemical techniques. The oxidation on glassy carbon electrode and reticulated vitreous carbon electrode occurs in only one step at 2.0 < pH < 12 involving a two-electron transfer to the amine group leading to the imide derivative. Dye solution was not decolorized effectively in this electrolysis process. Nevertheless, the oxidation of this dye on Ti/SnO2/SbO(x) (3% mol)/RuO2 (1% mol) electrode showed 100% of decolorization and 60% of total organic carbon removal in Na2SO4 0.2 M at pH 2.2 and potential of +2.4V. Experiments on degradation photoelectrocatalytic were also carried out for RB4 degradation in Na2SO4 0.1 M, pH 12, using a Ti/TiO2 photoanode biased at +1.0 V and UV light. After 1h of electrolysis the results indicated total color removal and 37% of mineralization.
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Affiliation(s)
- Patricia A Carneiro
- Departamento de Química Analitica, Instituto de Química, UNESP, Araraquara, CP 355, Sao Paulo CEP 14801-970, SP, Brazil
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Sousa WR, da Rocha C, Cardoso CL, Silva DHS, Zanoni MVB. Determination of the relative contribution of phenolic antioxidants in orange juice by voltammetric methods. J Food Compost Anal 2004. [DOI: 10.1016/j.jfca.2003.09.013] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Carneiro PA, Boralle N, Stradiotto NR, Furlan M, Zanoni MVB. Decolourization of anthraquinone reactive dye by electrochemical reduction on reticulated glassy carbon electrode. J BRAZIL CHEM SOC 2004. [DOI: 10.1590/s0103-50532004000400023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Zanoni MVB, Sene JJ, Selcuk H, Anderson MA. Photoelectrocatalytic production of active chlorine on nanocrystalline titanium dioxide thin-film electrodes. Environ Sci Technol 2004; 38:3203-3208. [PMID: 15224756 DOI: 10.1021/es0347080] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The production of chlorine and hypochlorite is of great economical and technological interest due to their large-scale use in many kinds of commercial applications. Yet, the current processes are not without problems such as inevitable side reactions and the high cost of production. This work reports the photoelectrocatalytic oxidation of chloride ions to free chlorine as it has been investigated by using titanium dioxide (TiO2) and several metal-doped titanium dioxide (M-TiO2) material electrodes. An average concentration of 800 mg L(-1) of free chlorine was obtained in an open-air reactor using a TiO2 thin-film electrode biased at +1.0 V (SCE) and illuminated by UV light. The M-doped electrodes have performed poorly compared with the pure TiO2 counterpart. Test solutions containing 0.05 mol L(-1) NaCl pH 2.0-4.0 were found to be the best conditions for fast production of free chlorine. A complete investigation of all parameters that influence the global process of chlorine production by the photo electrocatalytic method such as applied potential, concentration of NaCl, pH solution, and time is presented in detail. In addition, photocurrent vs potential curves and the reaction order are also discussed.
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Affiliation(s)
- Maria Valnice B Zanoni
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 North Park Street, Madison, Wisconsin 53706, USA
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Selcuk H, Sene JJ, Zanoni MVB, Sarikaya HZ, Anderson MA. Behavior of bromide in the photoelectrocatalytic process and bromine generation using nanoporous titanium dioxide thin-film electrodes. Chemosphere 2004; 54:969-974. [PMID: 14637354 DOI: 10.1016/j.chemosphere.2003.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this study, the photoelectrocatalytic behavior of bromide and generation of bromine using TiO2 was investigated in the separate anode and cathode reaction chambers. Our results show that the generation of bromine begins around a flatband potential of -0.34 V vs. standard calomel electrode (SCE) at pH 3.0 under UV illumination and increases with an increase in positive potential, finally reaching a steady-state concentration at 1.0 V vs. SCE. Maximum bromine formation occurs over the range of pH 4-6, decreasing sharply at conditions where the pH>7.
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Affiliation(s)
- Huseyin Selcuk
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 N. Park Street, Madison, WI 53706-1484, USA.
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Osugi ME, Carneiro PA, Zanoni MVB. Determination of the phthalocyanine textile dye, reactive turquoise blue, by electrochemical techniques. J BRAZIL CHEM SOC 2003. [DOI: 10.1590/s0103-50532003000400025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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34
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Zanoni MVB, Sene JJ, Anderson MA. Photoelectrocatalytic degradation of Remazol Brilliant Orange 3R on titanium dioxide thin-film electrodes. J Photochem Photobiol A Chem 2003. [DOI: 10.1016/s1010-6030(02)00320-9] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
Miconazole is reduced at mercury electrode above pH 6 involving organometallic compound formation, responsible for an anomalous polarographic behavior. The electrodic process presents a large contribution of the adsorption effects. The drug can be determined by cathodic stripping voltammetry from 8.0 x 10(-8) to 1, 5 x 10(-6) molL-1 in Britton-Robinson buffer pH 8.0, when pre-accumulated for 30s at an accumulation potential of 0V. A relative standard deviation of 3.8% was obtained for ten measurements of 1.0 x 10(-7) molL-1 miconazole in B-R buffer pH 8.0 and a limit detection of 1, 7 x 10(-8) molL-1 was determined using 60s of deposition time and scan rate of 100 mVs-1. The proposed method is simple, precise and it was applied successfully for the determination of the miconazole in pure form and in commercial formulations, showing mean recoveries of 99.7-98.4%.
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Affiliation(s)
- Francisco C Pereira
- Instituto de Química, Universidade Estadual Paulista, 14801-970, Araraquara, SP, Brazil
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Pereira FC, Zanoni MVB, Guaratini CCI, Fogg AG. Differential pulse polarographic determination of clotrimazole after derivatization with Procion Red HE-3B. J Pharm Biomed Anal 2002; 27:201-8. [PMID: 11682227 DOI: 10.1016/s0731-7085(01)00526-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Clotrimazole was shown to react at room temperature in Britton Robinson buffer pH 2 with the reactive dye Procion Red HE-3B. The product exhibited a differential pulse polarographic peak at -0.38 V, which was well separated from the peaks of the reactive dye at -0.08, -0.80 and -0.95 V, and this allowed the indirect determination of clotrimazole in the presence of excess of the reactive dye. The method has been applied satisfactorily to the determination of clotrimazole in pharmaceutical formulations, calibration graphs are rectilinear up to at least 40 microg ml(-1). The detection limit was calculated to be 2.6 microg ml(-1) (3 sigma).
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Affiliation(s)
- F C Pereira
- Departamento de Química Analitica, Instituto de Química-Universidade Estadual Paulista, Caixa Postal 355, 14800-900, SP, Araraquara, Brazil
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Pereira FC, Stradiotto NR, Zanoni MVB. Electrochemical reduction and cathodic stripping voltammetric determination of clotrimazole. J BRAZIL CHEM SOC 2001. [DOI: 10.1590/s0103-50532001000200013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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40
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Zanoni MVB, Moreira JC, Fogg AG. Use of solid-phase extraction cartridges with differential-pulse cathodic stripping voltammetry at a hanging mercury drop electrode: determination of nedocromil sodium and pentamidine isethionate in urine. Analyst 1995. [DOI: 10.1039/an9952000505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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