HPLC-QTOFMS法测定马来酸依那普利及中间体中的对甲苯磺酸乙酯

目的:建立HPLC-QTOF MS测定马来酸依那普利及中间体N-1-(S)-乙氧甲酰基-3-苯丙基]-L-丙氨酸中对甲苯磺酸乙酯的方法。方法:采用Eclipse plus C18色谱柱(3.0 mm×100 mm,1.8μm),以20 mmol·L-1甲酸铵水溶液(A)-乙腈(B)为流动相,梯度洗脱(0～2 min,10%→50%B;2～4 min,50%→60%B;4～7 min,60%→90%B;7～8 min,90%B),流速1.0 mL·min-1,柱温50℃;采用正离子模式采集数据。结果:对甲苯磺酸乙酯浓度在0.20～5.01μg.mL-1范围内线性关系良好(r=0.9955);日内和日间精密度良好,RSD小于6.7%;定量限和检测限分别为0.4 ng、0.2 ng;马来酸依那普利及中间体回收率(n=9)分别为102.6%和90.8%。结论:本法简便、灵敏,可用于对甲苯磺酸乙酯的定量研究。

HPLC-QTOF MS determination of ethyl p-toluenesulfonate in enalapril maleate and its intermediate

Objective:To establish a method of HPLC-QTOF MS to detect ethyl p-toluenesulfonate in enalapril maleate and intermediate.Methods:The method was achieved on a Eclipse plus C18 column(3.0 mm×100 mm,1.8 μm) utilizing a mobile phase of 20 mmol·L-1 ammonium formate(A)-acetonitrile(B) with gradient elution(0-2 min,10%→50%B;2-4 min,50%→60%B;4-7 min,60%→90%B;7-8 min,90%B) at the flow rate of 1.0 mL·min-1.And the temperature of column was set at 50 ℃;The data was acquired in positive ion mode.Results: Standard curve was linear in the range of 0.20-5.01 μg·mL-1(r=0.9955).The values of limit of quantification and limit of detection were 0.4 ng and 0.2 ng,respectively.RSDs for the intra-and inter-day were less than 6.7%.The recoveries(n=9) of ethyl p-toluenesulfonate in enalapril maleate and intermediate were 102.6% and 90.8%,respectively.Conclusion: The method is convenient and sensitive for detecting ethyl p-toluenesulfonate in enalapril maleate and intermediate.