琥乙红霉素与茜素红的荷移反应研究

Charge Transfer Reaction between Erythromycin Ethylsuccinate and Alizarin Red

采用紫外分光光度法研究了电子给体琥乙红霉素与π电子受体茜素红的荷移反应,建立了一种测定琥乙红霉素的荷移分光光度法。结果表明,琥乙红霉素与茜素红在乙醇-水(3∶7,体积比)溶液中,室温条件下即可形成1∶1稳定的荷移络合物,该络合物的最大吸收波长为535nm,表观摩尔吸光系数为5.96×103 L·mol-1·cm-1。琥乙红霉素的浓度在8~72μg·mL-1范围内服从比尔定律,R=0.9997。用于片剂中琥乙红霉素的测定时,回收率为97.5%~104.0%,相对标准偏差为1.9%~2.3%(n=5)。该法快速、简便、灵敏、准确,可作为琥乙红霉素的又一测定方法。

We studied the charge transfer reaction between erythromycin ethylsuccinate as electron donor and alizarin red asπ-electron acceptor by ultraviolet spectrophotometry.Meanwhile,we established a method of charge transfer spectrophotometry for the determination of erythromycin ethylsuccinate.The results show that the composition ratio of charge transfer complex is 1∶1 in ethanol-water(3∶7)solution at room temperature.The maximum absorption wavelength of the complex is 535 nm,and the apparent molar absorptivity is 5.96×10 3 L·mol^-1·cm^-1.When the concentraion of erythromycin ethylsuccinate is in the range of 8-72μg·mL^-1,the Beer′s Law is obeyed and the correlation coefficient is 0.9997.The recovery is 97.5%-104.0%and the relative standard deviation is 1.9%-2.3%(n=5)in determination of erythromycin ethylsuccinate in tablets.This method is rapid,simple,sensitive,and accurate.