阻抑动力学分光光度法测定微量碘  

Inhibition Kinetic Spectrophotometric Determination of Microamounts of Iodide

作　　者：严小平[1] 李立[1] 金建昌[1] 王智敏[1] 王芳权[1] 何方岳[1] 

机构地区：[1]浙江树人大学生物与环境工程学院,杭州310015

出　　处：《理化检验（化学分册）》2009年第2期185-186,219,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：基于在稀磷酸介质中，痕量碘离子对亚硝酸根催化溴酸钾氧化甲基红的的阻抑作用，提出了测定痕量碘离子的阻抑动力学分光光度分析的方法。测定碘离子的线性范围在0．66mg·L^-1以内，检出限（3Sb／K）为7．5×10^-6g·L^-1。用于海带及食盐中微量碘的测定，测定结果的相对标准偏差（n=6）在1．4％～2．2％之间，测得方法的回收率为99．7％～100．1％。Based on the inhibition action of microamounts of iodide ion on the catalytic reaction of nitrite on oxidation of methyl red by potassium bromate in dil. H3PO4 medium, a new method of inhibition kinetic spectrophotometric determination of trace amounts of iodide was proposed. Linear relationship between values of △A （difference of absorbances of the inhibition reaction system and the catalytic reaction system） and concentration of iodide ion was kept in the range within 0. 66 mg · L^-1 of solution. Detection limit （3Sb/K） found was 7. 5 × 10^-6g · L^-1. Samples of table salt and kelp were analyzed by the proposed method for contents of iodide, giving values of recovery and RSD＇s （n=6） in the ranges of 99.7%-100. 1% and 1.4%--2.2% respectively.

关 键 词：动力学分光光度法 阻抑反应 甲基红 碘 

分 类 号：O657.32[理学—分析化学]