猕猴血浆中SARS冠状病毒主蛋白酶肽类抑制剂N3的测定

目的建立测定猕猴血浆中N3的LC-MS/MS法。方法以ffiOBasiCC18（100mm×2.1 mm，5μm）色谱柱为 分析柱,流动相为乙腈-水（含0.2%甲酸）（55：45, F：F），采用电喷雾离子源（ESI）,正离子扫描方式，选择离子反应监测 （SRM）模式检测,用于定量分析的离子反应为m/z681.3-402.3。结果血浆中的N3用乙腈沉淀蛋白后，样品经LC-MS/MS 系统进行检测。在优化后的样品预处理、色谱及质谱条件下，LC-MS/MS法检测猕猴血浆中的N3,线性范围为20 -2500 μg·L^-1，准确度RE范围为-12.9% -2. 9 %，日内、日间精密度的RSD分别小于7.5% （ n =6）和7.8% （ n =18）;低、中、高 3个浓度（50、1000和2000μg·L^-1）犯质控样品的提取回收率分别为75.5 %、77.3 %和79.6 %。结论结果表明，该方法 具有灵敏、准确、快速等优点，适用于N3在猕猴体内的药代动力学研究。

Determination of Peptide Inhibitor N3 of SARS Corona-virus Main Protease in Rhesus Plasma

Objective To develop a high performance LC-MS/MS method for the determination of N3 in rhesus plasma. Methods The analysis was performed on a BioBasic C18 column （100mm×2.1 mm,5μm） with acetonitrile-water （ containing 0. 2% formic acid） （ 55 ： 45,V ：V ） as the mobile phase. A mass spectrometer equipped with electrospray ionization （ESI） source was used as the detector and operated in the positive ion mode. The selected reactions monitoring （SRM） mode with the transitions of m/z 681. 3/402. 2 was used to quantify N3. Results N3 in rhesus plasma was extracted by protein precipitation with acetonitrile,and the supernatant was injec-ted into the LC-MS/MS system for determination. Under optimized LC-MS/MS conditions, the standard curve was linear over the concentration range of 20 - 2500 μg·L^-1 for N3. The accuracy （ relative error,RE） of this method ranged from - 12. 9% to 2. 9% . The intra-day and inter-day precision （ relative standard deviation, RSD） was less than 7. 5% （ n =6） and 7. 8% （ n =18）,respectively. The recovery of the method for N3 of 50, 1000 and 2000μg·L^-1 in rhesus plasma was 75. 0% ,76. 9% and 79. 5% ,respectively. Conclusion The established method is shown to be sensitive,accurate,quick and effective for investigation of N3 pharmacokinetics in rhesus.