A novel non-enzymatic electrochemical uric acid sensing method based on nanohydroxyapatite from eggshell biowaste immobilized on a zinc oxide nanoparticle modified activated carbon electrode (Hap-Esb/ZnONPs/ACE).

Hydroxyapatite-derived eggshell biowaste (Hap-Esb) has been fabricated and developed for the electrochemical detection of uric acid (UA). The physicochemical characteristics of the Hap-Esb and modified electrodes were evaluated using a scanning electron microscope and X-ray Diffraction analysis. Utilized as UA sensors, the electrochemical behavior of modified electrodes (Hap-Esb/ZnONPs/ACE) was assessed using cyclic voltammetry (CV). The superior peak current response observed for the oxidation of UA at Hap-Esb/ZnONPs/ACE, which was 13 times higher than that of the Hap-Esb/activated carbon electrode (Hap-Esb/ACE) is attributed to the simple immobilization of Hap-Esb on zinc oxide nanoparticle-modified ACE. The UA sensor exhibited a linear range at 0.01 to 1 μM, low detection limit (0.0086 μM), and excellent stability, which surpass the existing Hap-based electrodes reported in the literature. The facile UA sensor subsequently realized is also advantaged by its simplicity, repeatability, reproducibility, and low cost, applicable for real sample analysis (human urine sample).