ZnO/RuO2 nanocomposite modified glassy carbon electrode as sensor for determination of exercise-induced myoglobin biomarkers

Abstract

A novel ZnO/RuO2 nanocomposite modified electrochemical sensor was developed for the rapid and ultrasensitive quantification of Mb biomarkers related to exercise-induced muscle injury. The sensor demonstrated a wide linear range from 0.1 to 100 nM along with an ultra-low detection limit down to 30 pM Mb under optimal conditions. A rapid response time below 10 s was achieved. The sensor surface showed excellent electrocatalytic activities towards Mb oxidation, attributing to the synergistic properties of the mixed transition metal oxide interface. Systematic investigations revealed reversible electrochemical behavior and diffusion controlled electron transfer kinetics governing the oxidation process. Negligible interferences were observed against potentially co-existing species. Spike-recovery experiments using real human serum samples yielded excellent recovery rates between 97.3% and 103.1%. Significantly enhanced post-exercise Mb levels up to 8.2 nM were successfully detected in clinical specimens, confirming the sensor's ability to sensitively monitor muscular trauma via minimally invasive blood tests. The sensor provided tangible analytical advantages over previous Mb detectors and immunoassays in terms of detection limit, sensitivity, simplicity and cost-effectiveness. Findings validate the feasible adoption of the sensor technology to facilitate prompt diagnosis of exercise-induced myoglobinemia in sports medicine clinics.