Determination of Trace Amounts of Iodine 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 methyl red by potassium bromate catalyzed by nitrite in dilute phosphoric acid medium.The linear range is in the range of 0—35μg/50mL with a detection limit of 7.5×10-9g/mL.The method was used for the determination of trace amounts of iodine in food samples with satisfactory results.