A green approach to uric acid detection using reduced graphene oxide-decorated with medium entropy alloy electrodes

In this study, a medium entropy alloy (MEA) composed of nickel, chromium, iron, and copper was synthesized and investigated as an efficient electrochemical sensor for uric acid detection. To further improve sensing performance, MEA particles were decorated over reduced graphene oxide (rGO), forming a composite with improved electrochemical activity. The composite was synthesized via a green approach involving mechanical milling of graphite with metal powders followed by sonication-based exfoliation of the milled mixture. Electrochemical sensing performance was evaluated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). An optimized 50:50 wt ratio of MEA to rGO demonstrated the most effective sensing response. The optimized MEA-rGO composite sensor exhibited a linear current response across a wide uric acid concentration range (100–1000 µM) with a high sensitivity of 27 µA·µM⁻¹ ·cm⁻². These findings highlight the potential of MEA-rGO composites as robust and sensitive electrochemical sensors for biomedical applications.