Atom-by-atom electrodeposited CuO nanostructures on carbon electrode for rapid detection of type II diabetes drug Gliclazide

CuO-modified SPCE enables sensitive electrochemical detection of gliclazide. • Electrodeposited CuO nanostructures increase electroactive surface area. • Oxidation of gliclazide follows proton-coupled two-electron transfer kinetics. • Exhibits low LODs (8.35 μM by LSV, 3.0 μM by amperometry) and wide linearity. • Demonstrates high stability, reproducibility, and recovery in real samples. The sensitive and selective detection of gliclazide (GLi), a critical antidiabetic drug, is essential for pharmaceutical quality control and therapeutic monitoring. This work presents a highly efficient electrochemical sensor based on a screen-printed carbon electrode modified with electrodeposited copper oxide nanoparticles (CuO/SPCE). Comprehensive physicochemical characterization confirmed the successful formation of a nanostructured CuO film, significantly enhancing the electroactive surface area. Cyclic voltammetry (CV) revealed a well-defined oxidation peak at 0.315 V with a peak current ( I ) of −2.725 μA at pH 4.0, indicating an irreversible, adsorption-controlled, proton-coupled two-electron transfer process. Linear sweep voltammetry (LSV) exhibited excellent linearity (10–107 μM, R 2  = 0.9890) with a limit of detection (LOD) of 8.35 μM, while amperometric detection further improved the sensitivity, yielding an LOD of 3.0 μM. The sensor demonstrated outstanding reproducibility (relative standard deviation, RSD = 5.28%), stability (RSD = 4.53%), and high recovery rates (93.21–109.28%) in real pharmaceutical samples. These findings highlight CuO/SPCE as an effective, rapid, and reliable platform for routine GLi monitoring in pharmaceutical and clinical settings. Download: Download high-res image (47KB) Download: Download full-size image