高锰酸钾-甲氧苄啶-硫代硫酸钠化学发光反应

Chemiluminescence System of KMnO_4-Trimethoprin-Na_2S_2O_3

在硫酸介质中，高锰酸钾可以氧化甲氧苄啶发生化学发光反应，硫代硫酸钠对这一化学发光反应有极强的增敏作用。采用流动注射技术，建立了高锰酸钾甲氧苄啶硫代硫酸钠化学发光体系测定甲氧苄啶的化学发光新方法．考察了各种影响因素，确立了反应的最佳条件。方法的检出限为３．８×１０－８ ｇ／ｍＬ甲氧苄啶；线性响应范围为１×１０－７～１×１０－５ ｇ／ｍＬ。对４×１０－６ ｇ／ｍＬ甲氧苄啶进行１１次平行测定，相对标准偏差为１．８％。方法已成功地用于片剂中甲氧苄啶含量的测定，结果与药典标准法测得值一致。

A chemiluminescence method based on the chemiluminescencereaction of KMnO4-trimethoprin (TMP) Na2S2O3 for the determination of TMP with flow injection technique was developed. The main facts which affected the chemiluminescence reaction were examined. Under optimum conditions, the linear range for the determination of TMP was 1×10-7～1×10- 5 g/mL and the detection limit was 3.8×10-8 g/mL. The relative standard deviation for the determination of 4×10-6 g/mL TMP ( n =11) was 1.8%. The method has been used to determine the TMP in tablets and the results were in good agreement with those obtained by classical method.