A new sensor based on In doped CeO2 nanoparticles modified glassy carbon paste electrode for sensitive determination of uric acid in biological fluids

Abstract

A novel In doped CeO2 nanoparticles modified glassy carbon paste electrode (nano-In–CeO2/GCPE) was prepared and applied for selective and sensitive electrochemical determination of uric acid (UA). In doped CeO2 nanoparticles were characterized by X-ray diffraction, energy-dispersed X-ray spectrometry (EDS) and transmission electron microscopy (TEM). Scanning electron microscopy (SEM) and cyclic voltammetry (CV) were employed for the surface analysis of the modified electrodes. Compared with undoped CeO2, the In (5wt.%) doped CeO2 modified electrode exhibits high effective surface area, more reactive site and excellent electrochemical catalytic activity toward the oxidation of UA. The prepared nano-In–CeO2/GCPE showed high selectivity and sensitive for UA oxidation over ascorbic and dopamine. This In–CeO2 nanoparticles modified electrode responded to UA linearly over a concentration range from 7.90×10−8 to 1.48×10−5M with a detection limit of 7.40×10−9M UA (1.24ng/mL). The fabricated sensor showed anti-interference ability against the physiological common interferents (i.e. adenine, guanine and xanthine) and provided to be useful for the determination of UA in human blood serum and urine samples with satisfactory results.