El-Didamony Akram M
Chemistry Department, Faculty of Science, Zagazig University, Zagazig, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2008 Mar;69(3):770-5. doi: 10.1016/j.saa.2007.04.032. Epub 2007 May 21.
A simple, rapid and sensitive spectrophotometric method has been proposed for the assay of benzydamine HCl (BENZ), levamisole HCl (LEV) and mebeverine HCl (MBV) in bulk and pharmaceutical formulations. The method based on the reaction of the selected drugs with methyl orange (MO) in buffered aqueous solution at pH 3.6. The formed yellow ion-pair complexes were extracted with dichloromethane and measured quantitatively with maximum absorption at 422 nm. The analytical parameters and their effects on the reported systems are investigated. The extracts are intensely colored and very stable at room temperature. The calibration graphs were linear over the concentration range of 2-10 microg ml(-1) for BENZ, 6-24 microg ml(-1) for LEV and 4-14 microg ml(-1) for MBV. The stoichiometry of the reaction was found to be 1:1 in all cases and the conditional stability constant (K(f)) of the complexes have been calculated. The proposed method was successfully extended to pharmaceutical preparations-tablets. Excipients used as additive in commercial formulations did not interfere in the analysis. The proposed method can be recommended for quality control and routine analysis where time, cost effectiveness and high specificity of analytical technique are of great importance.
已提出一种简单、快速且灵敏的分光光度法，用于测定原料药及药物制剂中的盐酸苄达明（BENZ）、盐酸左旋咪唑（LEV）和盐酸美贝维林（MBV）。该方法基于所选药物与甲基橙（MO）在pH 3.6的缓冲水溶液中发生反应。形成的黄色离子对络合物用二氯甲烷萃取，并在422 nm处进行定量测定，最大吸收波长为422 nm。研究了分析参数及其对所报道体系的影响。萃取物颜色深，在室温下非常稳定。校准曲线在BENZ浓度范围为2 - 10 μg ml⁻¹、LEV浓度范围为6 - 24 μg ml⁻¹、MBV浓度范围为4 - 14 μg ml⁻¹时呈线性。在所有情况下，反应的化学计量比均为1:1，并计算了络合物的条件稳定常数（K(f)）。所提出的方法成功扩展至药物制剂——片剂。商业制剂中用作添加剂的辅料不干扰分析。对于时间、成本效益和分析技术的高特异性至关重要时的质量控制和常规分析，可推荐使用所提出的方法。
