Potential-dependent simultaneous detection of uric acid and glucose using dual-function Ni@CNT supported carbon fiber electrodes

The development of non-enzyme electrochemical sensors is crucial for rapid and convenient detect the biomarkers of diabetes mellitus and hyperuricemia. In this study, we developed a bifunctional electrode comprising a core-shell Ni@CNT anchored on carbon fibers (CFs) and proposed potential-dependent techniques for simultaneous detection of UA and glucose. By adjusting the pH value of electrolyte to balance the oxidation potentials and signal intensities of UA and glucose, the Ni@CNT-CF electrode demonstrated good selectivity and wide linear range from 1 mu M to 1 mM for UA at 0.2 V and 1 mu M to 6 mM for glucose at 0.6 V. It also exhibited high sensitivity of 1.86 mu A mM- 1 mu g- 1 for UA and 1.52 mu A mM- 1 mu g- 1 for glucose, with low detection limits of 0.32 and 0.39 mu M, respectively. These excellent performance attributes to the high conductivity and corrosion resistance of CNT and high catalytic activity of embedded Ni nanoparticles. Furthermore, the Ni@CNT-CF electrode demonstrated significant recoveries of UA and glucose in both simulated fluid and real blood samples, highlighting its potential for practical applications in UA and glucose detection.