Autor(es)

Inoque, Neilio ; Araujo, Diele A. G. ; de Lima, Debora Machado ; Sousa, Raquel Maria Ferreira ; Paixao, Thiago Regis Longo Cesar ; Munoz, Rodrigo A. A.

• Tipo de documento: Artigo Científico
• Fonte: ACS FOOD SCIENCE & TECHNOLOGY; v. 4, n. 6, p. 9-pg., 2024-06-04.

Resumo

This paper describes a new analytical method based on laser-induced graphene (LIG) electrodes for evaluating antioxidant capacity in tea by quantifying the consumption of the 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical. The LIG electrodes were produced by pyrolysis using a CO2 infrared laser source (10 electrodes were produced in 5 min). The LIG sensor was coupled to a three-dimensional (3D)-printed batch-injection analysis cell to amperometrically detect the remaining DPPH. The sensing properties included a linear range from 2 to 900 mu mol L-1 (R-2 > 0.99), adequate limit of detection (LOD = 0.6 mu mol L-1), fast responses (similar to 10 s), and good precision relative standard deviation (RSD < 4.0%). The efficient concentration of tea samples necessary to reduce the initial DPPH concentration by 50% (EC50) was determined after incubation with DPPH radicals for 30 min. The results of EC50 showed good agreement with the conventional spectrophotometric results. Therefore, LIG electrodes are a powerful analytical tool for applications in teas. (AU)

• Processo FAPESP: 22/01810-5 - Plataformas microfluídicas fabricadas com fios têxteis e impressão 3d para eletroanálises de amostras clínicas, ambiental e biológicas
• Beneficiário: Diele Aparecida Gouveia Araújo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 18/08782-1 - Sensores químicos miniaturizados e integrados: novas plataformas de fabricação para aplicações biológicas, clínicas e ambientais
• Beneficiário: Mauro Bertotti
• Modalidade de apoio: Auxílio à Pesquisa - Temático