<p>In this study, a non-enzymatic glucose sensor was developed using a two-step electrodeposition process. A thin ZnO film was first deposited on a glassy carbon electrode (GCE), followed by the deposition of copper nanoparticles. The influence of electrodeposition parameters on the growth of ZnO-Cu/composite was investigated, leading to the identification of optimal conditions for efficient glucose oxidation. The electrocatalytic activity of the ZnO-Cu/GCE sensor was evaluated using cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The ZnO-Cu/GCE sensor exhibited the lowest charge transfer resistance (<i>R</i>_ct) and the highest double-layer capacitance values compared to the bare GCE, the ZnO/GCE and Cu/GCE electrodes. The enhanced performance is primarily attributed to the synergistic effect between Cu and ZnO, which significantly improves electrical conductivity. Moreover, this sensor presented a linear response to glucose concentrations ranging from 0.25 to 10&#xa0;mM, with an excellent detection limit (11.361&#xa0;µM) and a high sensitivity (504.83 μA mM⁻¹&#xa0;cm⁻²). It also demonstrated outstanding stability and reproducibility. Kinetic parameters for glucose oxidation were determined with an electron transfer coefficient (α) of 0.385 and a diffusion coefficient (<i>D</i>) of 38 × 10⁻⁵ cm²&#xa0;s⁻¹. Furthermore, the sensor maintained excellent selectivity in the presence of common interfering species. Its practical applicability was confirmed through successful glucose detection in real human saliva and urine samples, using chronoamperometric measurements. The observed current increase remained proportional to successive glucose, highlighting the sensor’s potential for real-world applications.</p> Graphical Abstract <p></p>