茚三酮为显色剂分光光度法测定氨苄西林钠

Spectrophotometric Determination of Ampicillin Sodium Using Ninhydrin as Chromogenic Agents

采用分光光度法研究了氨苄西林钠与茚三酮间的显色反应。确定了反应条件,建立了一种快速、简便测定氨苄西林钠的分光光度法。实验表明,氨苄西林钠与茚三酮在pH=5.4的水溶液中,沸水浴1 h可以反应完全,产物在λmax=564 nm下,表观摩尔吸光系数为3.72×103L/(mol.cm)。氨苄西林钠质量浓度在10～90 mg/L范围内服从比耳定律,相关系数为0.998 1,当氨苄西林钠浓度为40 mg/L时,测定结果的相对标准偏差为1.5%(n=6),回收率在99.0%以上。

The reaction between ampicillin sodium and ninhydrin was investigated by spectrophotometry. A simple and rapid method for the determination of ampicillin sodium has been optimized. The apparent molar absorptivity of complex is 3.72 × 10^3 L/（mol.cm） at 564 nm. Beer＇s law could be followed in the range of 10 -90 mg/L of ampicillin sodium with correlation coefficient of 0. 998 1. The relative standard deviation is 1.5% （n =6） and the recovery was over 99.0%.