Copper-modified stencil-printed amperometric sensor fabricated on polyimide substrate as a new strategy for non-enzymatic glucose detection

Glucose is a biomarker with extensive applications in biotechnology, food industry, and clinical diagnostics¹. Accurate glucose measurement is vital for managing diabetes, a widespread and deadly disease affecting millions worldwide, as noted by the World Health Organization (WHO)². This study proposes a miniaturized sensor of stencil-printed carbon electrodes (SPCE) fabricated on a polyimide substrate. Working electrode was modified with copper by electrodeposition using amperometric detection in an acidic medium containing 0.1 M H₂SO₄ and 10 mM CuSO₄, applying a potential of -2.0 V for 100 seconds, in order to enhance electrocatalytic surface to allow the formation of a porous copper layer due to the reduction processes of copper and hydrogen ions. Cyclic voltammetry (CV) was used to characterize glucose oxidation in a potential range of -0.6 V to +0.7 V at a scan rate of 50 mV/s and revealed an oxidation peak around 0.5 V. Amperometric detection studies aim to optimize analytical conditions for calibration curves and also Scanning Electron Microscopy (SEM) and Electrochemical Impedance Spectroscopy (EIS) will be used to characterize the proposed sensor. The copper-modified SPCE will be used to determine glucose levels in real human samples.