Enhanced Electrochemical Performance via Modified Surface Properties, Particle Size, and Flower-Like Morphology of NiO Nanostructures for the Sensitive and Selective Non-Enzymatic Detection of Uric Acid

In this study, luffa peel extract was employed to investigate its impact on the morphology, particle size, surface properties, optical band gap, and surface active sites of nickel oxide (NiO). Various analytical techniques revealed that the synthesized NiO nanostructures, prepared using 2 ml of luffa peel extract, exhibited a distinctive flower-like morphology, the smallest particle size, abundant surface oxygen vacancies, the narrowest optical band gap, and enhanced surface catalytic activity. The electrochemical non-enzymatic method demonstrated significant efficiency in oxidizing uric acid (UA) in phosphate buffer solution at pH 7.3, utilizing sample 3 of the NiO nanostructures. Sample 3 exhibited a broad linear detection range for UA, spanning from 0.1 mM to 15 mM, along with an exceptionally low limit of detection of 0.004 mM, as determined through chronoamperometry. Furthermore, sample 3 of NiO was found to be highly stable, reproducible, and selective. Non-enzymatic UA sensors were successfully applied to quantify UA levels in blood and urine samples, yielding highly accurate results with a relative standard deviation of less than 3%. This research highlights the potential of luffa peel extract in the development of a diverse range of electrocatalytic materials for applications in clinical diagnostics, biomedical research, and related fields.