Determination of Quercetin by a Siloxane-Polyester/Poly-L-Lysine Nanocomposite Modified Glassy Carbon Electrode

Autor(es)

de Castro Viana Pereira, Elaine Renata ^[1] ; Bessegato, Guilherme Garcia ^[1] ; Yamanaka, Hideko ^[1] ; Boldrin Zanoni, Maria Valnice ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, UNESP, Inst Chem, Dept Analyt Chem, BR-14800060 Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Analytical Letters; v. 49, n. 9, p. 1398-1411, 2016.
• Citações Web of Science: 4

Resumo

Poly-L-lysine incorporated in the nanocavities of polysiloxane-poly(propylene) oxide is reported as an electrochemical sensor for quercetin. A glassy carbon electrode coated by poly-L-lysine/polysiloxane-poly(propylene) oxide accumulated quercetin through hydrogen bonding in pH 2 ethanol/Britton-Robinson buffer. The catecol oxidation was monitored at 0.45V as a reversible two electron peak. The voltammetric response using the film electrode was 80% higher compared to a bare electrode. Square wave voltammetry was employed using an accumulation time of 8min and a linear relationship was obtained for concentrations of quercetin from 1.0x10(-8)mol L-1 to 1.0x10(-6)mol L-1. The limit of detection was 2.76 +/- 0.5x10(-9)mol L-1. The method was employed to determine quercetin in green tea, but did not show selectivity to catechin, which was oxidized at a similar potential. The measurements were validated by high-performance liquid chromatography. (AU)

• Processo FAPESP: 12/18357-0 - Estudo da degradação fotoeletrocatalítica de corantes cosméticos com eletrodos de nanotubos de TiO2 não dopados e dopados com Sb2S3
• Beneficiário: Guilherme Garcia Bessegato
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 08/10449-7 - Avaliação da ocorrência, toxicidade/genotoxicidade e processos para degradação de corantes em efluentes e águas superficiais
• Beneficiário: Maria Valnice Boldrin
• Modalidade de apoio: Auxílio à Pesquisa - Temático