荧光衍生法测定胶囊中苯甘孢霉素的含量

Determination of Cephalexin in Capsules by Fluorimetry

建立了用荧光分光光度法测定苯甘孢霉素含量的新方法。在近中性的介质中，苯甘孢霉素与Au（Ⅲ）发生配合反应生成荧光物质（λex=355nm，λem=438nm），在所选定的最佳条件下，苯甘孢霉素在0．40～20mg·L^-1范围内与体系荧光强度呈良好的线性关系，R=0．9982，对浓度为2．0mg·L^-1的苯甘孢霉素连续测定11次，其相对标准偏差（RSD）为2．48％，检出限为0．14mg·L^-1，平均回收率为100．4％。本法可用于片剂和胶囊中苯甘孢霉素含量的测定。

A fluorimetric method based on the reaction between cephalexin and metal ions Au（ Ⅲ） was developed for the determination of cephalexin. The linear relationship between the fluorescence intensity and the concentration of cephalexin is over the range of 0.40-20 mg·L^-1 with a correlation coefficient of 0. 9982. The detection limit is 0.14 mg·L^-1 and the relative standard deviation for the determination of 2. 0 mg·L^-1 cephalexin is 2. 48% （n = 11）. This method has been successfully applied to the determination of cephalexin in capsules.