琥乙红霉素与紫色素的荷移反应及其测定

SPECTROPHOTOMETRIC DETERMINATION OF ERYTHROMYCIN ETHYLSUCCINATE BASED ON THE CHARGE TRANSFER REACTION BETWEEN ERYTHROMYCIN ETHYLSUCCINATE AND PURPURIN

建立了一种快速测定琥乙红霉素的荷移分光光度法。琥乙红霉素与紫色素在乙醇-水介质中发生电荷转移反应，荷移络合物在546nm波长处有最大吸收，表观摩尔吸光系数为9．18×10^3L·mol^-1·cm^-1，络合物的组成为1：1，稳定常数为1．9×10^5。药物质量浓度在O～90mg·L^-1范围内服从比耳定律，相关系数为0．9997，当琥乙红霉素质量浓度为40mg·L^-1时，6次测定结果的相对标准偏差为1．24％。测定了琥乙红霉素片剂中有效成分的含量，并与药典方法进行比较，结果基本吻合。

A spectrophotometric method for the determination of erythromycin ethylsuceinate was described in this paper. The method was established based on the charge transfer reaction between erythromycin ethylsuecinate as donor and purpurin as acceptor in water--alcohol medium. The molar ratio and stability constant of charge transfer complex is 1 ： 1 and 1.9 × 10^5 , respectively. The apparent molar absorptivity of the color complex is 9, 18×10^3L .mol^-1 . cm^-1 at 546 nm： Beer＇s law is obeyed in the range of 0--90 mg. L-1 of erythromycin ethylsuccinate, Correlation coefficient is 0. 999 7. The relative standard deviation of six determinations is 1.24G at the concentration leveI of 40 mg . L^-1. The proposed method has been applied to the determination of erythromycin ethylsuccinate in medical tablets giving results in consistency with the results obtained by the pharmacopeia method.