HPLC法测定复方美托拉宗片中美托拉宗和缬沙坦的相关物质

目的 建立复方美托拉宗片中美托拉宗和缬沙坦相关物质的HPLC测定方法.方法 采用Agilent Eclipse SB-C18色谱柱(4.6 mm×250 mm,5μm),以0.01 mol/L磷酸二氢钾溶液(pH=3.5)-乙腈为流动相,梯度洗脱,流速:1.0 ml/min,柱温:30℃,检测波长:237 nm,进样量:20μl.结果 美托拉宗、缬沙坦及其相关物质之间分离度良好;美托拉宗在3~30μg/ml、缬沙坦在0.1~2.0μg/ml、缬沙坦杂质B在0.08~2.0μg/ml范围内峰面积与浓度线性关系良好;其平均回收率分别为102.97%、100.81%和100.44%;该法的重复性及中间精密度均符合要求;检测用溶液在室温条件下放置24 h稳定.结论 该法专属性强、灵敏度高、准确可靠,可用于复方美托拉宗片中美托拉宗和缬沙坦相关物质测定.

Determination of related substances for metolazone and valsartan in compound metolazone tablets by HPLC

Objective To establish an HPLC method to determine the related substances of metolazone and valsartan in com?pound metolazone tablets. Methods An Agilent Eclipse SB-C18 column (4.6 mm × 250 mm,5 μm) was used with 0.01 mol/L KH2PO4 buffer(pH=3.5)-acetonitrile as the mobile phase with gradient elution at a flow rate of 1.0 ml/min. The column temperature was 30℃ and the detection wavelength was 237 nm. Injection volume was 20 μl. Results Metolazone,valsartan and related sub?stance B of valsartan were separated completely. The calibration curves were linear within the range of 3-30μg/ml for metolazone, 0.1-2.0μg/ml for valsartan and 0.08-2.0μg/ml for related substane B of valsartan. The average recoveries were 102.97%,100.81%and 100.44%,respectively. The repeatability and intermediate precision met with requirements. The test solution was stable within 24 h. Conclusion The method is specific,sensitive,accurate and reliable,thereby can be used for the determination of metolazone and valsartan related substances in compound metolazone tablets.