Self-Adhesive Mask and Homemade Carbon Ink: Turning Unusable Screen-Printed Electrodes into a New Voltammetric Sensor

Abstract

Screen-printed carbon electrodes (SPCEs) are widely employed in sensing due to their low cost, especially the model DRP-110. However, their disposable nature limits their long-term applications. In this work, we present a sustainable methodology for recovering the electrode model DRP-110-U75. Unusable SPCEs were made usable again after employing a stencil-printing approach. After recuperating the electrodes (Re-SPCE), characterization experiments upon the Re-SPCEs have indicated similar morphological aspects and catalytic ability when compared to as-purchased SPCEs. As a proof of concept, voltammetric analysis of dopamine (DOP) in artificial urine and tryptophan (TRP) in supplement capsules was successfully employed, exhibiting limits of detection of 2.15 and 0.2 μmol L–1 for DOP and TRP, respectively. These results confirm that the proposed method can extend the life cycle of SPCEs.