Plataformas eletroquímicas baseadas em material carbonáceo modificadas com estruturas híbridas: da construção à determinação de moléculas de interesse alimentício, ambiental e clínico

Abstract

In this work, a lab-made sensor was constructed and printed on polyethylene (SPE) and optimized with graphite conductive ink and stained-glass varnish (70%/30%), demonstrating good reproducibility, stability, and excellent electroactivity. The constructed electrochemical devices exhibit robustness and practicality in terms of the defined chemical modifications for diverse applications across various sample classes. Using the SPE platform, modified systems were developed with Au nanoparticles, polymers (chitosan, poly-beta-cyclodextrin, poly-L-cysteine, polyaniline), Printex L6 carbon, deep eutectic solvent, and enzymes. These modified electrodes enabled the detection of various analytes in a wide range of sample types, including estriol (LOD: 1.88 µM), catechin (LOD: 2.52 nM), theobromine (LOD: 0.076 µM), folic acid (LOD: 0.018 µM), and phytic acid (LOD: 0.8 µM). The platforms demonstrated high sensitivity, selectivity, and applicability in diverse matrices across environmental (river water, tap water), food (teas, cocoa products, spinach leaves), and clinical (saliva, blood, sweat, urine) fields. These sensors stand out as sustainable and effective alternatives to traditional analytical separation and quantification methods. The results presented in this study advance the frontier of knowledge in electrochemical sensing for environmental, clinical, and food monitoring applications.