Metwally F H, Alwarthan A A, Al-Tamimi S A
Department of Analytical Chemistry, Faculty of Pharmacy, Cairo University, Kasr el Aini, Egypt.
Farmaco. 2001 Aug;56(8):601-7. doi: 10.1016/s0014-827x(01)01100-4.
A flow-injection spectrophotometric method is described for the determination of cefadroxil (I) and cefotaxime (II). The method is based on the hydrolysis of the cephalosporin with sodium hydroxide whereby the sulfide ion is produced. The latter is allowed to react with N,N-diethyl-p-phenylenediamine sulfate (N,N-DPPD) and Fe (III), and the blue color produced is measured at 670 nm (method A). Linear calibration graphs are obtained in the range 36.34-109.2 and 95.48-477.4 microgml(-1) for I and II, respectively. The experimental limits of detection (three times the noise signal) are 0.036 and 0.048 microgml(-1) for I and II, respectively. The total flow-rate is 5.3 ml min(-1) for both drugs. Alternately, the sulfide ion produced is allowed to react with p-phenylenediamine dihydrochloride (PPDD) and Fe (III), and the violet color produced is measured at 597 nm (method B). Linear calibration graphs are obtained in the range 0.5-400 and 0.5-450 microg ml(-1) for I and II, respectively. The limits of detection are 0.4 and 0.2 microg ml(-1) for I and II, respectively. The total flow-rate is 3 ml min(-1) for both drugs. The methods have been successfully applied to the analysis of some pharmaceutical formulations, particularly of the injection and capsule types. The relative standard deviation (RSD) (n = 10) at the 50 and 100 microg ml(-1) levels of I and II were 0.83-0.77 and 0.9-0.8% with N,N-DPPD and PPDD as reagents, respectively. Recoveries were quantitative; the results obtained agreed with those obtained by other reported methods.
本文描述了一种流动注射分光光度法，用于测定头孢羟氨苄（I）和头孢噻肟（II）。该方法基于头孢菌素与氢氧化钠水解生成硫离子，硫离子再与硫酸N,N - 二乙基对苯二胺（N,N - DPPD）和铁（III）反应，在670 nm处测量产生的蓝色（方法A）。I和II分别在36.34 - 109.2和95.48 - 477.4 μg/ml范围内获得线性校准曲线。I和II的实验检测限（噪声信号的三倍）分别为0.036和0.048 μg/ml。两种药物的总流速均为5.3 ml/min。或者，生成的硫离子与对苯二胺二盐酸盐（PPDD）和铁（III）反应，在597 nm处测量产生的紫色（方法B）。I和II分别在0.5 - 400和0.5 - 450 μg/ml范围内获得线性校准曲线。I和II的检测限分别为0.4和0.2 μg/ml。两种药物的总流速均为3 ml/min。这些方法已成功应用于一些药物制剂的分析，特别是注射剂和胶囊剂。以N,N - DPPD和PPDD作为试剂，I和II在50和100 μg/ml水平时的相对标准偏差（RSD）（n = 10）分别为0.83 - 0.77和0.9 - 0.8%。回收率为定量；所得结果与其他报道方法一致。
