Spectrophotometric determination of uric acid in urine and blood samples

Abstract

The simple, fast, accurate, and sensitive spectrophotometric method was described for the determination of uric acid in blood, urine, and meat. The method depended on the unreacted Ce4+ was determined by using two different dyes indigo carmine and methyl orange at 610 nm and 505 nm respectively. The spectrophotometric method involves the oxidation of uric acid with ceric ammonium nitrate used as a strong oxidant in presence of acetate buffer pH (4) as an acidic medium with indigo carmine dye and the presence of sulfuric acid (pH 0.2) as an acidic medium with methyl orange dye. Optimum conditions affecting the method were studied such as pH and buffer, oxidant volume, dye volume, sequence of addition, time, organic solvent, and temperature. Beer's law was obeyed in the concentration range of (0.016-6.7) mg mL-1 with indigo carmine, with molar absorptivity 0.396×102 L mol-1cm-1and (0.084-2.3) mg mL-1 with methyl orange, with molar absorptivity 2.08118×102 L mol-1cm-1.