A novel GLUT-4 electrochemical immunosensor based on a poly (thionine)-gold nanoparticle nanocomposite: Combining complex capacitance and dissolved oxygen to obtain an analytical signal

Autor(es)

Olean-Oliveira, Andre ; Seraphim, Patricia Monteiro ; Portugal, Miqueias L. ; Teixeira, Marcos F. S.

• Tipo de documento: Artigo Científico
• Fonte: BIOSENSORS & BIOELECTRONICS; v. 275, p. 8-pg., 2025-05-01.

Resumo

Detection of glucose transporter 4 (GLUT4) is essential for understanding various physiological and pathological processes. This work reports the development of a novel electrochemical immunosensor for the direct detection of GLUT4, employing dissolved oxygen as a redox probe. This molecular oxygen-sensitive response is mediated by a redox-conductive polymer based on thionine. The sensor platform was fabricated via a one-step electropolymerization of thionine and gold nanoparticles (AuNPs) onto a platinum screen-printed electrode (OleanOliveira et al., 2022a). The immunosensor was then constructed by physical adsorption of a GLUT4 antibody onto the poly(thionine)-AuNP composite surface. This label-free approach eliminates the need for secondary antibodies or enzymes. The immunosensor performance was evaluated using electrochemical impedance spectroscopy (EIS). The sensing mechanism relies on impedance changes; increasing GLUT4 concentrations lead to increased impedance due to enhanced surface blocking upon GLUT4-antibody binding. This interaction impedes oxygen diffusion to the polymer redox sites, resulting in increased electrical resistance. Analysis of the redox capacitance as a function of frequency demonstrates a decrease in the capacitive arc with increasing GLUT4 concentration. (AU)

• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 04/10130-0 - Avaliação da expressão de proteínas transportadoras de glicose (gluts) central e perifericamente em ratos resistentes à insulina
• Beneficiário: Patricia Monteiro Seraphim
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 24/08769-6 - DESENVOLVIMENTO DE UM GENOSSENSOR BASEADO EM NANOPARTICULA DE PRATA ENCAPSULADO EM POLÍMERO Pi-CONJUGADO PARA O MONITORAMENTO DE miRNA EM CELULAS PATOGENICAS
• Beneficiário: Miquéias de Lima Portugal
• Modalidade de apoio: Bolsas no Brasil - Mestrado