Autor(es):
de Souza, João Carlos [UNESP] ; Zanoni, Maria Valnice Boldrin [UNESP] ; Oliveira-Brett, Ana Maria
Data: 2020
Identificador Persistente: http://hdl.handle.net/11449/200888
Origem: Oasisbr
Assunto(s): Electrochemical oxidation; Genotoxic precursors; Glassy carbon electrode; Hair dyes; P-aminophenol; P-toluenediamine; Electrochemical oxidation; Electrochemical oxidation; Genotoxic precursors; Genotoxic precursors; Glassy carbon electrode; Glassy carbon electrode; Hair dyes; Hair dyes; P-aminophenol; P-aminophenol; P-toluenediamine; P-toluenediamine
Descrição
Made available in DSpace on 2020-12-12T02:18:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Fundação para a Ciência e a Tecnologia
Programa Operacional Temático Factores de Competitividade
The p-toluenediamine (PTD) and p-aminophenol (PAP), genotoxic precursor agents widely used in permanent hair dyeing formulations, electrochemical mechanisms and evaluation in biological fluids, at a glassy carbon electrode, in a wide pH range, by cyclic, differential pulse, and square wave voltammetry, were investigated. The oxidation of both PTD and PAP is reversible. The PTD two electrons and two protons transfer diffusion-controlled reaction occurs at the molecule nitrogen atoms in the amine groups. Also PAP oxidation is a two electrons and two protons transfer diffusion-controlled reactions, and occur at the nitrogen and oxygen atoms of the molecule amine and hydroxyl groups. An electrochemical oxidation mechanism for PTD and PAP is proposed. The PTD and PAP diffusion coefficients, DPTD = 1.57 × 10−5 cm2 s−1 for PTD, and DPAP = 1.03 × 10−5 cm2 s−1 for PAP, were determined. The electrochemical quantification in 0.10–1.00 μM concentration range showed a detection limit of 0.12 μM for PTD and 0.17 μM PAP. A new electroanalytical method for the determination of PTD and PAP in fetal bovine serum biological fluid, and in artificial urine samples, using differential pulse voltammetry, was also developed.
Department of Chemistry Faculty of Sciences and Technology University of Coimbra
Institute of Chemistry Department of Analytical Chemistry National Institute of Alternative Technologies for Detection Toxicological Assessment and Removal of Micropollutants and Radioactive (INCT-DATREM) São Paulo State University (UNESP)
Institute of Chemistry Department of Analytical Chemistry National Institute of Alternative Technologies for Detection Toxicological Assessment and Removal of Micropollutants and Radioactive (INCT-DATREM) São Paulo State University (UNESP)
