硝普钠分光光度法测定卡托普利

A Novel Technique for the Determination of With Captoptril Sodium Nitroprusside as a Chromogenic Reagent by Spectrophotometry

建立了以硝普钠为显色剂分光光度法测定卡托普利的方法。实验表明,卡托普利与硝普钠作用形成一种淡黄色产物,对产物进行加入顺序、缓冲溶液p H值、试剂配比、反应时间、反应温度等反应条件,获得此方法的最适宜条件,其最大吸收波长为397.00 nm。卡托普利浓度在1.3~3.3 mg/L范围内有良好的线性关系,回归方程为A=0.1022 c-0.1097,线性相关系数为0.9995,检出限（3σ/k）为0.0214 mg/L,回收率为95.28%。

A selective spectrophotometric method for determination of captopril uses sodium nitroprusside as a chromogenic reagent. The method was based on the reaction of captoptril with alkaline sodium nitroprusside reagent at room temperature forming a yellowish colored chromogen measured at 397.00 nm. The conditions affecting the reaction （ sodium nitroprusside volumed, order, pH, colordeveloping time, temperature） were optimized. The absorbance of the solution with different concentration was tested by spetrophotometry and the standard curves were used to carry on the analysis. Under the optimum conditions, good linear relationship （ r = 0.9995 ） was obtained between the absorbance and the concentration of eaptopril. The liner regression equation is A = 0. 1022c - 0. 1097, the limit of detection （3cr/k） was 0.0214. The recovery ratio was above 95.28%. The method was accrtate, fast and simple. The method was used for the determination of captopfil in phamaeeutical sample with satisfactory results.