Stripping Square Wave Voltammetry for the Determination of Uric Acid in Human Urine using Iron(III) Doped Zeolite Graphite Powder Composite Modified Glassy Carbon Electrode

A novel stripping square wave voltammetric method has been developed for the determination of uric acid (UA) in untreated human urine. In this study, we introduced a new electrode based on iron(III) doped zeolite graphite powder composite (GPC) modified glassy carbon electrode (GCE). Iron(III) loaded in zeolite matrix can increase anodic peak current by adsorption of uric acid compound on the electrode surface. The results indicated that Fe+3 Y/GPC modified GCE facilitate the determination of uric acid with good sensitivity and reproducibility. The optimum conditions selected for the determination of uric acid using square wave voltammetry were: pulse amplitude 40 mV, Scan rate100 mV/s, accumulation time 30 s, and accumulation potential +100 mV, pH of supporting electrolyte (pH)=7. Under these optimum conditions, the oxidation peak current of UA increased linearly with concentration in the range of 2.0×10−6 to 8.0×10-5 mol L−1 with linear equation, correlation coefficient (R2) and detection limit (based on the formula LoD=3δ/m) of Ipa (μA)=0.1952–0.3252 C (μM), 0.99903 and 2.32×10-7 mol L-1, respectively.