Determination of iodide in urine based on chemiluminescence system of cerium (IV)-tween 40-iodide

In acidic medium, the oxidation reaction of cerium (IV) with iodide can produce strong chemiluminescence (CL) in the presence of surfactant tween 40 as an enhancer. On this basis, a flow injection method with CL detection was established for the determination of iodide. The method is simple, rapid and effective to determine iodide in the range of 8.0 x 10(-8)-5.0 x 10(-5) mol/L with a determination limit of 5.0 x 10(-8) mol/L. The relative standard deviation is 2.7% for the determination of 5.0 x 10(-6) mol/L iodide (n=11). The method has been applied to determine the content of iodide in urine with satisfactory results. Furthermore, it is suggested that the light emission from cerium (IV)-tween 40 reaction is probably because of the formation of singlet oxygen O-1*(2) and the emitter is excited oxygen molecular pairs O-2((1)Delta(g))O-2(1 Sigma(-)(g)) (C) 2011 Elsevier B.V. All rights reserved.