Inhibitory Kinetic Spectrophotometric Determination of Trace Iodinein in Food with Cationic Surfactant Sensitizer

An inhibitory kinetic spectrophotometric method was proposed for the determination of trace iodine. The method is based on the inhibition effect of iodine on the nitrite-catalyzed oxidation of menthylene blue by potassium bromate in dilute sulphuric acid medium. The linear range of the determination is 0 to 480 g/L,and the detection limit is 3.7×10-7 g/L. This method is simple,rapid and highly sensitive. It has been used for determination of trace iodine in salt with satisfactory results.