Erk N
Faculty of Pharmacy, Department of Analytical Chemistry, University of Ankara, Turkey.
J Pharm Biomed Anal. 2001 Feb;24(4):603-11. doi: 10.1016/s0731-7085(00)00434-9.
A new simple, precise, rapid and selective reversed-phase high performance liquid chromatographic (HPLC) and two spectrophotometric methods have been described for resolving binary mixture of losartan potassium and hydrochlorothiazide in the pharmaceutical formulations. The first method, is based on HPLC on a reversed-phase column using a mobile phase 0.01 N sodium dihydrogen phosphate:methanol:acetonitrile (8:2:1 v/v/v) (pH 5.5) with detection at 265.0 nm. The second method, is depend on ratio derivative spectrophotometry, the amplitudes in the first derivative of the ratio spectra at 238.360 nm and at 230.423 nm were selected to simultaneously determine losartan potassium and hydrochlorothiazide in the mixture. The third method, based on compensation technique is presented for the derivative spectrophotometric determination of binary mixtures with overlapping spectra. By using ratios of the derivative maxima or the derivative minimum, the exact compensation of either component in the mixture can be achieved, followed by its determination. The accuracy and precision of the methods have been determined and they have been validated by analysing synthetic mixtures containing losartan potassium and hydrochlorothiazide. The methods do not require any separation step. The methods were also applied to the determination of losartan potassium and hydrochlorothiazide in pharmaceutical preparations. The analytical results were quite good in all cases.
已描述了一种新的简单、精确、快速且具有选择性的反相高效液相色谱（HPLC）法以及两种分光光度法，用于分离药物制剂中氯沙坦钾和氢氯噻嗪的二元混合物。第一种方法基于反相柱HPLC，使用流动相0.01 N磷酸二氢钠：甲醇：乙腈（8:2:1 v/v/v）（pH 5.5），检测波长为265.0 nm。第二种方法依赖于比率导数分光光度法，选择238.360 nm和230.423 nm处比率光谱一阶导数的振幅来同时测定混合物中的氯沙坦钾和氢氯噻嗪。第三种方法基于补偿技术，用于导数分光光度法测定光谱重叠的二元混合物。通过使用导数最大值或导数最小值的比率，可以实现混合物中任何一种成分的精确补偿，随后进行测定。已确定了这些方法的准确性和精密度，并通过分析含有氯沙坦钾和氢氯噻嗪的合成混合物进行了验证。这些方法不需要任何分离步骤。这些方法还应用于药物制剂中氯沙坦钾和氢氯噻嗪的测定。在所有情况下，分析结果都相当不错。
