Sulfamethoxazole Detection in Milk Using a Carbon-Based Printed Electrode: Enhanced Selectivity and Response Stability by Pulse-Amperometry

Autor(es)

Boane, Anastacio A. ; Araujo, Diele A. G. ; Munoz, Rodrigo A. A. ; Paixao, Thiago R. L. C. ; Richter, Eduardo M.

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Electrochemical Society; v. 172, n. 2, p. 8-pg., 2025-02-01.

Resumo

A simple, low-cost, and lab-made carbon-based electrode was developed for the fast and selective determination of sulfamethoxazole (SMX) in milk samples, requiring only minimal sample preparation (dilution in supporting electrolyte). A custom-made conductive ink (composed of glass varnish, graphite, acetone) was applied to a plastic surface to fabricate a flow-through amperometric sensor integrated into a portable Batch Injection Analysis (BIA) system. This method enhanced selectivity and reduced electrode contamination. The optimized pulsed amperometric waveform conditions included two detection pulses (+1.0 V and +1.3 V) and two cleaning pulses (+1.5 V and -1.5 V), resulting in a linear response from 1.0 to 20.0 mu mol L-1, with a detection limit of 0.31 mu mol L-1. The stability and reproducibility of the method were confirmed, exhibiting low relative standard deviations (RSD <= 8.3%). The system exhibited excellent recovery for spiked milk samples at concentrations of 5.0 mu mol L-1 (68 +/- 7%), 10.0 mu mol L-1 (103 +/- 7%), and 20.0 mu mol L-1 (115 +/- 7%), demonstrating high accuracy and minimal matrix interference. This approach offers a rapid, accurate, and reliable method for the analysis of complex samples, particularly for onsite detection of SMX in milk. Low-cost and and lab-made disposable carbon-based sensors for complex sample analysis.Portable amperometric method for selective determination of sulfamethoxazole in milk samples.Simple and rapid sample preparation step (dilution in supporting electrolyte). (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: 23/00246-1 - Dispositivos miniaturizados visando à produção em larga escala: fabricação, caracterização e aplicações in-situ
• Beneficiário: Mauro Bertotti
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• 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