Annealed Cu-MOF based electrodes for epinephrine detection

Abstract

The detection of stress marker epinephrine (EP) has garnered significant attention due to its critical role in mental health disorders, immune dysfunction, nicotine dependence and cardiovascular diseases. Herein, we report an electrochemical sensor based on copper metal–organic frameworks (Cu-MOFs) for the sensitive detection of EP. The annealed Cu-MOF's increased crystallinity, low band gap, and improved surface properties synergistically enhance its electrocatalytic activity. The sensor exhibits a linear response in the 1–10 µM range with a sensitivity of 0.76 ± 0.02 µA cm⁻² µM⁻¹ and a limit of detection (LOD) of 0.15 ± 0.03 µM (n = 5) towards epinephrine detection. Furthermore, it showed a remarkable reproducibility, selectivity against common interferents, and stability during repeated analysis. Real-sample analysis in both serum and urine exhibited recovery rates up to 96% (serum) and 88.3% (urine), respectively. Our findings suggest that the annealed Cu-MOF is a cost-effective and excellent electrode material with significant potential for applications in next-generation sensors for clinical diagnostics.