Simultaneous determination of direct yellow 50, tryptophan, carbendazim, and caffeine in environmental and biological fluid samples using graphite pencil electrode modified with palladium nanoparticles

Autor(es)

Wong, Ademar ^{[1, 2]} ; Santos, Anderson Martin ^[2] ; Alves, Rafael da Fonseca ^[1] ; Vicentini, Fernando Campanha ^[3] ; Fatibello-Filho, Orlando ^[2] ; Taboada Sotomayor, Maria Del Pilar ^[1]

Afiliação do(s) autor(es)

^[1] State Univ Sao Paulo, Inst Chem, Dept Analyt Chem, Araraquara, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem, Rod Washington Luis Km 235, Sao Carlos, SP - Brazil

^[3] Univ Fed Sao Carlos, Ctr Nat Sci, Rod Lauri Simoes Barros Km 12, Buri, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Talanta; v. 222, JAN 15 2021.
• Citações Web of Science: 2

Resumo

The present study reports the development of graphite pencil electrode modified with palladium nanoparticles (PdNPs) and its application as an electrochemical sensor for the simultaneous detection of direct yellow 50, tryptophan, carbendazim and caffeine in river water and synthetic urine samples. The combination involving the conductive surface of the graphite pencil electrode (GPE) and the enlargement of the surface area caused by the use of palladium nanoparticles (PdNPs) led to the improvement of the analytical performance of the proposed device. The surface of the GPE-PdNPs was characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The charge transfer kinetics of the electrode was evaluated based on the elec-trochemical analysis of the potassium ferricyanide redox probe. Using square wave voltammetry (SWV), welldefined and fully resolved anodic peaks were detected for the analytes, with peak-to-peak potential separation not less than 200 mV. Under optimised conditions, the following linear range concentrations were obtained: 0.99-9.9 mu mol L-1 for direct yellow 50; 1.2-12 mu mol L-1 for tryptophan; 0.20-1.6 mu mol L-1 for carbendazim; and 25-190 mu mol L-1 for caffeine. The sensor showed good sensitivity, repeatability, and stability. The device was successfully applied for the determination of analytes in urine and river water samples, where recovery rates close to 100% were obtained. Due to its low cost and reusability by simple polishing, the sensor has strong potential to be used as an electrochemical sensor for the determination of different analytes. (AU)

• Processo FAPESP: 14/50945-4 - INCT 2014: Instituto Nacional de Tecnologias Alternativas para Detecção, Avaliação Toxicológica e Remoção de Micropoluentes e Radioativos
• Beneficiário: Maria Valnice Boldrin
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 19/00677-7 - RADes-MIP - preparação e síntese de materiais para desenvolvimento de dispositivos de análise rápida para monitoramento de poluentes emergentes usando polímeros biomiméticos altamente seletivos baseados na tecnologia de impressão molecular
• Beneficiário: Maria Del Pilar Taboada Sotomayor
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 20/01050-5 - Desenvolvimento e aplicação de sensores eletroquímicos e fotoeletroquímicos para a determinação de contaminantes emergentes em amostras de águas naturais
• Beneficiário: Orlando Fatibello Filho
• Modalidade de apoio: Auxílio à Pesquisa - Regular