邻二氮菲分光光度法测定头孢曲松钠粉针剂含量

在一定温度下,头孢曲松钠能将Fe(Ⅲ)还原成Fe(Ⅱ),还原生成的Fe(Ⅱ)在pH为5.0的CH3COOH-CH3COONa缓冲介质中,与邻二氮菲发生配位反应形成稳定的橘红色配合物,其最大吸收波长为510nm.建立了Fe(Ⅲ)-头孢曲松钠-邻二氮菲体系分光光度法间接测定头孢曲松钠的新方法.实验表明,在最佳的实验条件下,头孢曲松钠浓度在0.26~8.8μg/mL范围内与吸光度呈良好线性关系.线性回归方程为A=0.224 3C+0.058 5,线性相关系数R=0.998 4,表观摩尔吸光系数ε=1.48×105 L/(mol·cm),检出限为0.011μg/mL.该法用于分析注射用头孢曲松钠粉针剂的含量,回收率在97.5%~102.5%.

Spectrophotometric Determination of Ceftriaxone Sodium for Injection by 1,10-phenanthroline

Fe(Ⅲ)could be reduced to form Fe(Ⅱ)by ceftriaxone sodium.In the CH3COOH-CH3COONa(pH=5.0)buffer solutions,the orange complex was formed by the coordination reaction between Fe(Ⅱ)and 1,10-phenanthroline,and the maximal absorption wavelength of the product was 510 nm.Based on this,we established a novel method of using the Fe(Ⅲ)-ceftriaxone sodium-1,10-phenanthroline system to determine the cetriaxone sodium for injection by spectrophotometry.The experiment showed that under the optimum conditions,agood linear relationship was obtained between the absorbance and the concentration of cetriaxone sodium in the range of 0.26-8.80μg/mL.The linear regression equation was A=0.224 3C(μg/mL)+0.058 5with a correlation coefficient of 0.998 4and the apparent molar absorption coefficient was 1.48×105 L/(mol·cm).Besides,the detection limit was 0.011μg/mL and the recoveries were from 97.5%to 102.5%.This method had been successfully applied to the determination of cetriaxone sodium in pharmaceuticals with satisfactory results.