Determination of Trace Amounts of Iodine in Food by Inhibition Kinetic Spectrophotometry

A kinetic spetrophotometric method for determination of trace amounts of iodine was developed.The method was based on the inhibition effect of iodine on the nitrite catalyzed oxidation of cresol red by potassium bromate catalyzed by nitrite in dolute sulfuric acid medium.The linear range of determination was 0 ～ 0.62 μg/mL with a detection limit of 7.43×10-9 g/mL.The method was used for the determination of trace amounts of iodine in food samples with satisfactory results.