Zahra Hashemzaei - Inorganic Research Laboratory, Department of Chemistry, University of Sistan and Baluchestan, Zahedan, Iran
Hamideh Saravani - Inorganic Research Laboratory, Department of Chemistry, University of Sistan and Baluchestan, Zahedan, Iran
Mahmood Sharifitabar - Department of Materials Engineering, Faculty of Engineering, University of Sistan and Baluchestan, Zahedan, Iran
Mahdi Shahbakhsh - Analytical Research Laboratory, Department of Chemistry, University of Sistan and Baluchestan, Zahedan, Iran

Sponge-like porous cerium oxide particles were prepared through the self-propagating high-temperature synthesis process. Then, the synthesized powder was used to modify the carbon paste electrode (CPE/porous CeO۲) for voltammetric determination of uric acid (UA) in biological fluids. Under optimal conditions, the linear concentration-response relationship was in the range of ۰.۲۵-۱۰ and ۱۰-۳۰۰ µM, and a detection limit of ۶۰ nM (S/N=۳) was obtained. In addition, the proposed sensor showed excellent selectivity towards UA over common co-existing species such as ascorbic acid, ibuprofen, dopamine, and acetaminophen. Good repeatability of sensor responses (Relative standard deviation (RSD) < ۳.۲%), superior reproducibility (RSD < ۲.۸%), and excellent storage stability (error < ۵% after ۱ month storage at room temperature) along with appropriate recovery values (in the range of ۹۹.۲ -۱۰۲.۷%) demonstrate the applicability of CPE/porous CeO۲ for the determination of UA levels in biological fluids. 

Porous cerium oxide powder, Modified carbon paste electrode, Uric acid, Voltammetric determination