Belal Saied, Abdel-Razak Omayma, El-Walily Abdel-Fattah, Bakry Rania
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, University of Alexandria, Alexandria 21521, Egypt;
Int J Biomed Sci. 2011 Dec;7(4):289-94.
Two spectrophotmetric methods based on combined redox - ligand exchange reactions were developed for the determination of captopril and penicillamine in pure form and in their dosage forms. The first method is based on attenuating the absorbance of a ternary complex: silver (I) - bromopyrogallol red - phenanthroline in a buffer solution of pH6-8. The method has the concentration ranges 2-10 μg mL(-1) and 0.5-1.75 μg mL(-1) for captopril and penicillamine respectively, and the detection limits 7.1 × 10(-2) and 5.7 × 10(-2) μg mL(-1) for captopril and penicillamine respectively. The second method is based on decreasing the absorbance of a chloroformic solution of copper (II) - oxine chelate when shaken with the drug solution in buffer medium of pH 8. The drugs were determined in the concentrations 30-90 μg mL(-1) and 30-100 μg mL(-1) for captopril and penicillamine respectively, and the detection limits 0.94 and 1.76 μg mL(-1) for captopril and penicillamine respectively. The proposed methods were applied in the analysis of both compounds in their pharmaceutical preparations, and results were favorably compared with reference spectrophotometric methods regarding accuracy and precision.
开发了两种基于氧化还原-配体交换反应联用的分光光度法，用于测定纯品及剂型中的卡托普利和青霉胺。第一种方法基于在pH6 - 8缓冲溶液中减弱三元配合物：银（I）-溴邻苯三酚红-菲罗啉的吸光度。该方法测定卡托普利的浓度范围为2 - 10 μg mL(-1)，测定青霉胺的浓度范围为0.5 - 1.75 μg mL(-1)，卡托普利和青霉胺的检测限分别为7.1×10(-2)和5.7×10(-2) μg mL(-1)。第二种方法基于在pH 8缓冲介质中，当铜（II）-8-羟基喹啉螯合物的氯仿溶液与药物溶液振荡时吸光度降低。测定卡托普利的浓度范围为30 - 90 μg mL(-1)，测定青霉胺的浓度范围为30 - 100 μg mL(-1)，卡托普利和青霉胺的检测限分别为0.94和1.76 μg mL(-1)。所提出的方法应用于药物制剂中两种化合物的分析，在准确度和精密度方面，结果与参考分光光度法相比具有优势。
