KMnO_4-I^--H_2CO体系化学发光法测定食品中的微量碘

Study on determination of micro amounts of iodine in food with chemiluminesence reaction of potassium permanganate-I-formaldehyde system

研究了KMnO4-I--H2CO体系化学发光,从而建立了一种测定食品中微量碘的新方法。讨论了各种反应物浓度、酸度、干扰离子等因素对测定结果的影响。I-浓度在1.0×10-6～4.0×10-5g/ml范围内与化学发光强度有较好的线性关系。对1.0×10-5g/ml的I-进行了11次平行测定,相对标准偏差为2.8%,方法的检出限为2.4×10-8g/ml,结果令人满意。

Chemiluminesence Reaction of Potassium Permanganate-I - -Formaldehyde System was investigated in the paper.A new method for determination of micro amount of iodine in food was developed.The effect of factors like reag ents' concentrations acidity,disturbing ions,etc.On the analytical results were studied.Under optimal condition,the linear rang e for the determination of I - was 1.0×10 -6 ～4.0×10 -5 g /ml and the detection limit was 2.4×10 -8 g /ml,the relative standard deviation for the determination of 1.0×10 -5 g /ml I - (n=11)was 2.8%.The results are satisfactory.