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

Abstract

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.