目的:建立以高效液相色谱-荧光检测法测定美托洛尔血药浓度的方法。方法:色谱柱为Symmetry C18,流动相为乙腈-水-三乙胺-磷酸(110:390:2.5:1.6),荧光检测波长为激发波长(Ex)=265nm、发射波长(Em)=298nm,流速为0.8mL.min-1,进样量为20μL。结果:美托洛尔血药浓度在2.0～100.0μg.L-1范围内线性关系良好(r=0.9996);低、中、高3种浓度的平均相对回收率分别为99.73%、98.21%、99.38%,日内RSD分别为2.89%、2.36%、1.32%,日间RSD分别为3.73%、3.03%、2.25%,最低检测限为1.0μg.L-1。结论:本方法精密、准确、特异性强、回收率高、操作简便,适用于临床血药浓度监测及药动学研究。 Objective: To establish a method for the determination of metoprolol in plasma by high performance liquid chromatography-fluorescence detection. Methods: The chromatographic column was Symmetry C18 with the mobile phase of acetonitrile-water-triethylamine-phosphoric acid (110: 390: 2.5: 1.6). The fluorescence detection wavelength was Ex = 265nm and the emission wavelength was 298nm. Flow rate of 0.8mL.min-1, injection volume of 20μL. Results: The linear range of metoprolol was 2.0-100.0μg.L-1 (r = 0.9996). The average relative recoveries of low, medium and high concentrations were 99.73% and 98.21% respectively, The RSDs were 2.89%, 2.36% and 1.32%, respectively. The daytime RSD was 3.73%, 3.03% and 2.25%, respectively. The lowest detection limit was 1.0μg.L-1. Conclusion: The method is accurate, accurate, specific, high recovery, easy to operate, suitable for clinical blood drug concentration monitoring and pharmacokinetic studies.