A cost-effective screen-printed electrochemical sensor enhanced with Printex L6 carbon and poly-L-cysteine for catechin detection in tea and water matrices

Autor(es)

Oliveira, Igor G. S. ; Gallina, Fernando C. ; Bimbi Junior, Fausto E. ; Santos, Anderson M. ; Lanza, Marcos R. V. ; Barros, Willyam R. P.

• Tipo de documento: Artigo Científico
• Fonte: Microchemical Journal; v. 209, p. 10-pg., 2025-02-01.

Resumo

This study developed a low-cost graphite screen-printed polyethylene-based electrode (SPPE) modified with carbon black and p-L-cysteine (p-L-Cys) for catechin (CAT) detection. The SPPE was modified with Printex L6 carbon - immersed in chitosan dispersion (PL6C@Chi), and p-L-Cys, which gave rise to the proposed SPPE/ PL6C@Chi/p-L-Cys sensor. The SEM images of the sensor revealed that the electrode had a high surface area covered by p-L-Cys polymeric film. The SPPE/PL6C@Chi/p-L-Cys sensor was characterized by increased hydrophobicity, as evidenced by its lower contact angle and higher electrical resistance compared to sensor without p-L-Cys. Differential pulse voltammetry was used for the detection of 4.0 x 10-5 mol L- 1 CAT in 0.10 mol L- 1 PBS at pH 7.0 and under a fixed concentration. The analytical curve was constructed in the concentration range of 5.00 x 10-9 to 1.00 x 10-4 mol L- 1, where a limit of detection of 2.52 x 10-9 mol L- 1 was obtained. The recovery analysis conducted on the samples of green and black tea and tap water using the proposed method resulted in high recovery rates- from 97.6 to 104.6 %. In addition, the interference analysis conducted using six different compounds showed no interference in the electrochemical detection of CAT. These findings show that the electrochemical technique developed in this study holds significant promise for CAT detection in environmental and tea samples and has great potential for practical applications in quality control. (AU)

• Processo FAPESP: 23/14335-6 - Desenvolvimento de sensores eletroquímicos descartáveis para a determinação e monitoramento online de contaminantes emergentes em processos de degradação
• Beneficiário: Anderson Martin dos Santos
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 22/12895-1 - Processos avançados para a degradação de poluentes emergentes: materiais catalíticos, sensores eletroanalíticos e divulgação científica
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 22/04053-0 - Síntese de novos nanocatalisadores heterogêneos à base de ferro (FeSe2 e Fe3O4) para aplicação na degradação de drogas psiquiátricas via processo foto-eletro-Fenton
• Beneficiário: Fausto Eduardo Bimbi Júnior
• Modalidade de apoio: Bolsas no Brasil - Doutorado