Microwave-Assisted One-Pot Synthesis of Medium-Entropy Oxides for Dual-Mode Electrochemical and Colorimetric Analysis of Sweat Biomarkers

) detection with a LOD of 2.2 μM and a selective "signal-off" response for glutathione (GSH) quantification (LOD: 0.01 μM) through an inhibitory binding mechanism. Mechanistic studies establish that the versatile catalytic performance originates from the synergistic interplay between M(II)/M(III) redox cycling, superoxide radical generation at oxygen vacancies, and efficient electron transfer. The entropy-stabilized structure maintains 92% of its activity over 20 days without refrigeration. These findings establish multimetallic entropy engineering as a powerful strategy for creating stable, high-performance nanozymes suitable for wearable biosensors and point-of-care diagnostics.