Engineering a polymerized ZIF-67 functionalized graphene oxide nanointerface as an efficient electrochemical platform...

This study presents a simple and cost-effective electrochemical platform for the simultaneous determination of dapagliflozin (DAP) and clopidogrel (CLP), two drugs widely used in the management of heart failure and coronary heart disease. The electrochemical sensor was fabricated by incorporating ZIF-67 nanocomposites with reduced graphene oxide (rGO) nanosheets onto the surface of a pencil graphite electrode (PGE). The resulting modified electrode exhibited high voltammetric responses toward DAP and CLP, with a distinct separation of 0.25 V between their oxidation peak potentials, enabling their reliable simultaneous detection. The physicochemical characteristics of the modified electrode were systematically investigated using cyclic voltammetry (CV), scanning electron microscopy (SEM), powder X-ray diffraction (pXRD), and Fourier-transform infrared (FT-IR) spectroscopy. Notably, the sensor achieved low limits of detection of 0.27 nmol L^-1 for CLP and 0.85 nmol L^-1 for DAP, demonstrating high analytical sensitivity. The proposed voltammetric platform provided selective analytical performance and was successfully applied to the determination of DAP and CLP in pharmaceutical dosage forms as well as spiked human plasma samples.