HPLC法测定卡托普利原料及片剂中3种异构体

Determination of three isomers in captopril API and tablets by HPLC

目的:建立HPLC法同时测定卡托普利原料药及片剂中3种异构体含量。方法:采用Chiralpak IG手性柱(250 mm×4.6 mm, 5μm);流动相A为正己烷-三氟乙酸(100∶0.1),流动相B为无水乙醇-三氟乙酸(100∶0.1),梯度洗脱;流速为1.0 mL·min^(-1);柱温为35℃;检测波长为215 nm;进样量为10μL。结果:该方法专属性良好,片中辅料无干扰,卡托普利与3种异构体彼此间的分离度均良好;各异构体平均加样回收率分别为99.6%、102.1%、93.6%,RSD分别为1.7%、1.4%和2.0%;重复性RSD均小于2.0%;供试品溶液至少在24 h内稳定;非对映异构体Ⅰ、对映异构体、杂质F的定量限分别为0.91、0.99、3.23μg·mL^(-1),检测限分别为0.27、0.30、0.97μg·mL^(-1);非对映异构体Ⅰ、对映异构体和杂质F分别在1.82~45.51、0.99~39.71、3.23~40.33μg·mL^(-1)范围内,峰面积与浓度的呈良好的线性关系(r为0.999 0~1.000 0)。3批原料中杂质F含量分别为0.04%、0.04%、0.03%,非对映异构体Ⅰ和对映异构体均未检出;对应3批制剂中杂质F的含量分别为:0.03%、0.03%、0.03%,非对映异构体Ⅰ和对映异构体均未检出。结论:方法学验证结果表明,该方法适用于卡托普利原料及片剂中3种异构体测定。

Objective:To establish an HPLC method for simultaneous determination of three isomers in captopril API and tablets.Methods:A Chiralpak IG chiral column(250 mm×4.6 mm,5μm)was adopted.The mobile phase A was n-hexane-trifluoroacetic acid(100∶0.1)and the mobile phase B was anhydrous ethanol-triflu-oroacetic acid(100∶0.1)with gradient elution.The flow rate was 1.0 m L·min^(-1).The temperature of the col-umn was set at 35℃,and the wavelength was set at 215 nm.The injection volume was 10μL.Results:The method had a good specificity,and no interferences from the excipients were found.Captopril and its three isomers were well separated.The average recoveries were 99.6%,102.1%and 93.6%,with RSD of 1.7%,1.4%and 2.0%,respectively.The RSD of repeatability were all less than 2.0%.The test solution was stable after 24 h.The quantification limits of diastereoisomerⅠ,enantiomer and impurity F were 0.91,0.99 and 3.23μg·mL^(-1),respectively.The detection limits were 0.27,0.30 and 0.97μg·mL^(-1),respectively.The calibration curve showed good linearity over the range of 1.82-45.51μg·mL^(-1) of diastereoisomerⅠ,0.99-39.71μg·mL^(-1) of enantiomer,3.23-40.33μg·mL^(-1) of impurity F(r was 0.9990-1.0000),respectively.The contents of impurity F in three batches of captopril were 0.04%,0.04%and 0.03%,respectively.The contents of impurity F in three batches of captopril tablets were 0.03%,0.03%and 0.03%,respectively.No diastereoisomerⅠor enantiomer were detected in captopril and tablets.Conclusion:The methodology validation results showed that the method is suitable for the determination of three isomers in captopril and tablets.