本文建立了同时测定大鼠肝微粒体孵育液中Ｒ（）和Ｓ（＋）美西律的气相色谱／火焰离子化检测方法。首先，将美西律从微粒体孵育液中提取出来；然后，与手性试剂Ｓ（）Ｎ三氟乙酰基脯氨酰氯反应形成酰胺类非对映体衍生物；最后，采用高分辨毛细管气相色谱分离测定。分析方法的线性范围为５０～５０００μｇ／ｍｌ；平均回收率Ｒ（）美西律是９３３１±５５９％，Ｓ（＋）美西律是９３１０±５１１％（ｎ＝１０）；检测限是１０μｇ／ｍｌ，定量限是５０μｇ／ｍｌ（ＲＳＤ＜１６５％）。该法已用于Ｒ（）和Ｓ（＋）美西律在大鼠肝微粒体中的氧化代谢研究 In this paper, a simultaneous gas chromatography / flame ionization detection method for simultaneous determination of R () and S (+) Meixi law in rat liver microsomal incubation was established. First, the mexiletine was extracted from the microsomal incubation; and then, with the chiral reagent S  ()  N trifluoroacetyl prolyl chloride to form amide diastereomer derivatives; Finally, using High Resolution Capillary Gas Chromatography Separation and Determination. The linear range of the analytical method was 50 ~ 5000 μg / ml. The average recovery rate was 9331 ± 559% for R  () method and 93  for S (+) Meixi law. 10 ± 511% (n = 10). The detection limit was 1.0 μg / ml and the limit of quantification was 50 μg / ml (RSD <165%). This method has been applied to the oxidative metabolism of R ()  and S (+)  mexiletine in rat liver microsomes