液相色谱-串联质谱法监测血清茶碱浓度及室间质量评价

目的对液相色谱-串联质谱(LC-MS/MS)检测茶碱进行方法学评价,探讨其在茶碱治疗药物监测(TDM)中的应用。方法在血清添加放射性核素内标茶碱-D6,经蛋白沉淀稀释后采用LC-MS/MS测定。以Capcell C18 MGⅢ(100 mm×2.0 mm,5μm)为分析柱进行反相色谱分离;以0.1%甲酸乙腈-0.1%甲酸水20∶80(v/v)]为流动相,流速为0.3 m L/min;以电喷雾离子化串联四级杆质谱、正离子多反应监测进行定量检测。用建立的方法从2008年起连续参加卫生部临检中心茶碱TDM室间质量评价。结果 LC-MS/MS检测茶碱的线性范围为1~50μg/m L,批内和批间精密度分别为2.26%~6.65%和4.70%~6.84%,准确度分别为94.14%~104.00%。单个样品的监测分析时间为3.5 min。冻融(-30℃室温反复解冻3次)、室温放置24 h、自动进样器放置24 h、长期保存(-30℃放置28 d)的稳定性均良好。LC-MS/MS测定结果与室间质量评价靶值偏差为2.75%,斜率为1.04,相关系数(r2)为0.983。结论该LC-MS/MS采用放射性内标稀释,具有简单、快速、特异性和灵敏度较好的特点,连续6年测定结果符合全国室间质量评价要求,可用于茶碱的临床TDM。

Liquid chromatography-tandem mass spectrometry for the monitoring of theophylline concentration in serum and its application to external quality assessment

Objective To perform the methodology evaluation of a liquid chromatography-tandem mass spectrometry （LC-MS /MS）for the determination of theophylline in serum,and to investigate the application significance in the therapeutic drug monitoring （TDM） for theophylline. Methods After being added with radionuclide theophylline-D6 as internal standard,serum samples were treated with protein precipitation and determined by LC-MS /MS.A reverse phase chromatographic separation was performed on Capcell C1 8 MG Ⅲ analytical column （1 00 mm × 2.0 mm,5 μm）by using 0.1 % formic acid in acetonitrile and 0.1 % formic acid in water 20∶80 （v/v）]as mobile phase.The flow rate was 0.3 mL/min.Theophylline and internal standard were monitored by a positive electrospray ion-tandem mass spectrometry system.The proficiency performance of LC-MS /MS was tested by participation to external quality assessment of theophylline TDMfor the National Center for Clinical Laboratory.Results The linear range of LC-MS /MS for the determination of theophylline was 1 -50 μg/mL.The accuracy was 94.1 4%-1 04.00% with within-run and between-run precisions of 2.26%-6.65% and 4.70%-6.84%.The run time was 3.5 min per sample.Stabilities were good under 3 cycles of frozen-thaw for 3 times from -30 ℃ to room temperature,room temperature for 24 h, autosampler for 24 h and -30℃ for 28 d.The external quality assessment proficiency test showed the bias of 2.75%, regression slope of 1 .04 and correlation coefficient （r2 ）of 0.983.Conclusions The radionuclide internal standard-dilution LC-MS /MS is simple,rapid,specific and sensitive for the determination of serum theophylline.It is comparable with the external quality assessment proficiency test for consecutive 6 years,and it is suitable for theophylline TDM in clinical practice.