Content Determination of Uric Acid by Flow Injection Chemiluminescence

OBJECTIVE:To establish a novel,rapid and sensitive method for the content determination of uric acid. METHODS:Chemiluminescence generated by ascorbic acid reacting with fluorescein-copper-surfactant could be selectively quenched in the presence of uric acid in alkaline solution. Based on flow injection,flow injection chemiluminescence was developed to determine the contents of uric acid directly. The concentrations of reagents were sodium hydrate(0.5 mol/L),fluorescein(5.0×10-4mol/L),Cu2+(1.0×10-4mol/L),CTMAB(5.0×10-3mol/L),ascorbic acid(25 mg/L). The flow rates of main and donkey pumps were set at2.5 ml/min with negative high voltage of 800 V. RESULTS:The linear range of uric acid was 0.1-20 mg/L(r=0.999 0)with an average recovery of 99.63%(RSD=1.2%,n=11). The detection limit was 3.3×10-2mg/L. CONCLUSIONS:This method is convenient,sensitive and selective,and can provide a new method for the content determination of uric acid in urine sample.