硝普钠分光光度法测定头孢他啶

Spectrophotometric Determination of Ceftazidime Using Sodium Nitroprusside

建立了硝普钠分光光度法测定头孢他啶的方法。实验结果表明,在碱性条件下,头孢他啶与硝普钠以1∶2的化学计量比反应形成一种红褐色产物,其最大吸收波长为528 nm。头孢他啶在2.50～810 mg/L浓度范围内与吸光度呈良好线性关系,线性回归方程为A=0.02704+0.00218ρ(mg/L),线性相关系数r=0.9987,表观摩尔吸收系数ε528=1.2×103L/(mol·cm),检测限(3σ/k)为1.38 mg/L。本方法操作简便、快速,成功用于药品中头孢他啶含量的测定。

A new method is proposed to determine ceftazidime using sodium nitroprusside. In an alkaline solution, a brown product is formed by the reaction of ceftazidime with sodium nitroprusside with the stoichiometric ratio of 1∶2. The amount of ceftazidime can be determined owing to the absorbance of the colored product. Absorbency is linear with the concentration of ceftazidime in the range of 2.50~810 mg/L, and the regression equation is A=0.02704＋0.00218ρ（mg/L） with a correlation coefficient of 0.9987. The apparent molar absorption coefficient and the detection limit are 1.2×103 L/（mol·cm） and 1.38 mg/L, respectively. This method is simple and fast, the study indicated that the method could be applied to the determination of ceftazidime in injection with satisfactory results.