Cost-effective quantification of uric acid using niobium oxide and graphene oxide-modified pencil-drawn electrodes on PVC substrates

Autor(es)

Saraiva, Douglas P. M. ; Ferreira, Bruno ; Ribeiro, Leonardo M. A. ; Paixao, Thiago R. L. C. ; Bertotti, Mauro

• Tipo de documento: Artigo Científico
• Fonte: ANALYTICAL METHODS; v. 16, n. 43, p. 6-pg., 2024-09-30.

Resumo

This study introduces a cost-effective approach for quantifying uric acid (UA), the main antioxidant species in human physiology and implicated in inflammatory regulation. Using a PVC substrate and pencil drawing technique, electrodes were fabricated and modified with niobium oxide and graphene oxide via a straightforward "drop casting" method. The nanostructures of the substrate, electrode, and modified electrode were evaluated using SEM images. The synergistic effect between these materials significantly facilitated the uric acid oxidation process with a 400 mV peak potential shift and 45% current increase. The evaluation of the electrode's response to common blood and urine components showed minimal deviation. Among the components tested-ascorbic acid, glucose, nitrate, nitrite, cysteine, urea, creatinine, and ammonium ion-only the ammonium ion exhibited a 10% interference at concentrations commonly found in urine. The sensors showed a good detection limit of 8.7 mu mol L-1, with a wide linear range from 8.7 to 2000 mu mol L-1 with a correlation factor of 0.9993 for five different sensors. The reproducibility and repeatability of the produced sensors were estimated by the RSD at 4% and 1%, respectively. Synthetic urine samples spiked exhibited reliable analysis, with recovery values within a 5% error margin. This work presents a practical, simple, and affordable sensor platform for rapid and accurate UA quantification. A low-cost sensor for uric acid (UA) quantification was developed using PVC electrodes modified with niobium oxide and graphene oxide. The sensor provided reliable results for the analysis of UA in synthetic urine samples. (AU)

• 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: 23/02572-3 - Obtenção de informações químicas em cérebros de rato com um potenciostato portátil
• Beneficiário: Douglas Philip Martinez Saraiva
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico