Sensor eletroquímico obtido por impressão 3D para a determinação de glutationa

• Ano de defesa: 2025
• Autor(a) principal: LOPES, Carlos Eduardo Costa
• Orientador(a): SILVA, Iranaldo Santos da , Documento sob sigilo. Prazo provável para disponibilização total: Janeiro de 2026. Motivo do sigilo: A dissertação só poderá ser totalmente disponibilizada após a publicação do artigo científico relacionado.
• Banca de defesa: SILVA, Iranaldo Santos , DANTAS, Luiza Maria Ferreira , ANGNES, Lúcio
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Maranhão
• Programa de Pós-Graduação: PROGRAMA DE PÓS-GRADUAÇÃO EM QUÍMICA/CCET
• Departamento: DEPARTAMENTO DE QUÍMICA/CCET
• País: Brasil
• Palavras-chave em Português: sensores eletroquímicos; impressão 3D; manufatura aditiva; glutationa.
• Palavras-chave em Inglês: electrochemical sensors; modified electrode; 3d printing; additive manufacturing.
• Área do conhecimento CNPq: Físico-Química
• Link de acesso: https://tedebc.ufma.br/jspui/handle/tede/6531

Glutathione is an antioxidant found in the tissues of animals, plants, and microorganisms. This compound plays an important role in the organism, and altered levels may be associated with several diseases. For this reason, the development of easily implemented methodologies to monitor this compound in routine analyses is necessary. Thus, this work presents a simple, fast, and low-cost alternative for determining glutathione through electrochemical instrumentation. For the development of this project, a conductive filament based on carbon black and polylactic acid (PLA) was used to manually print electrodes using a 3D printing pen. The electrodes were modified with a dispersion of carbon black and cobalt phthalocyanine, prepared in an aqueous solution containing 20% of ethanol. The analysis system employed amperometric detection with constant stirring provided by a 12 V motor sourced from an obsolete printer. Glutathione determination was performed at a detection potential of 0.00 V, ensuring satisfactory method performance without the need for binding agents to secure the modification on the electrode surface. A sensitivity of 0.0149 A L mol°' was achieved, with a linear working range of 5.0 to 180.0 pmol LU and a determination coefficient of R2 = 0.9933. Additionally, the detection and quantification limits were 1.30 and 4.50 Mmol LU, respectively. The method was applied to supplement samples and yielded results consistent with the manufacturer's stated values.