Dendritic Fe₂O₃-rGO nanoarchitectures for electrochemical uric acid sensing coupled with explainable machine...

Uric acid (UA) is an important biomarker that is associated with metabolic and renal disorders and demands sensitive detection methods. In this work, a dendritic Fe₂O₃-reduced graphene oxide (FOG) nanocomposite was prepared by a one-pot hydrothermal process and used to modify a glassy carbon electrode (GCE) for UA sensing. The synthesized composites were characterized by XRD, Raman spectroscopy, FESEM, HRTEM, and XPS to study their morphology, structure and properties as well as the chemical interactions between Fe₂O₃ and rGO. The synergistic effect of dendritic Fe₂O₃ and conductive rGO enhanced the accessibility of electrolyte, electron transfer and active sites. Electrochemical studies confirmed a well-defined oxidation peak at 0.304 V for UA, demonstrating excellent electrocatalytic activity. The sensor offered a linear range of 11-189 µM, a detection limit of 3.07 µM, and a sensitivity of 471.1 µA µM^-1 cm^-2. High stability, repeatability, and reproducibility were achieved, establishing FOG@GCE as a cost-effective platform for clinical UA detection. Beyond conventional peak-current calibration, a leakage-aware explainable ML framework interrogates multidimensional DPV information. Gaussian process regression achieved R ² = 0.996, RMSE = 3.6 µM, and MAE = 2.9 µM under nested validation, while SHapley Additive exPlanations (SHAP) enabled interpretation links predictive performance to physically meaningful electrochemical descriptors. This integration of heterointerface engineering, electrochemical sensing, uncertainty-aware prediction, and explainable AI establishes a compelling framework for next-generation intelligent chemical sensing.