液相色谱-串联质谱法快速测定兔血清及组织中痕量氟尿嘧啶

目的建立灵敏、快速的液相色谱-串联质谱法测定兔血清及组织中氟尿嘧啶的浓度。方法血清及组织样本经乙酸乙酯一步提取后,以乙腈-水(70:30,V/V)为流动相,Hypercarb C_(18)柱分离,采用电喷雾电离源,以多反应离子检测(MRM)方式进行负离子检测。用于定量分析的离子反应分别为m/z128.9→m/z41.9(氟尿嘧啶)和m/z188.7→m/z41.9(内标,溴尿嘧啶)。结果测定血清中氟尿嘧啶的线性范围为0.25～50μg·L~(-1),定量下限为0.25μg·L~(-1)。日内、日间精密度(RSD)均小于11%。食管组织中氟尿嘧啶的线性范围为0.5～100μg·L~(-1),定量下限为0.50μg·L~(-1)。日内、日间精密度(RSD)均小于10%。结论该法选择性强、灵敏度很高、操作简便、分析时间短,且可同时测定血清及组织中药物浓度,适用于极低浓度氟尿嘧啶生物样本的大批量检测。

Trace-level determination of fluorouracil in rabbit serum and tissue by a rapid LC-MS/MS

AIM To develop a sensitive and rapid LC-MS/MS method for the determination of fluorouracil in rabbit serum and tissues.METHODS After a one-step extraction by ethyl acetate,internal standard bromouracil and fluorouracil from serum and esophagus were separated on a Hypercarb C_(18) column.The mobile phase consisted of acetonitrile-water(70:30,V/V),at a flow-rate of 0.60 mL·min~(-1).An Applied Biosystems 3200Q tandem mass spectrometer equipped with electrospray ionization source was used as detector and was operated in the negative ion mode.Multiple reaction monitoring(MRM) using the precursor to product ion combinations of m/z 128.9→41.9 and m/z 188.7→41.9 was performed to quantify fluorouracil and the internal standard,respectively.RESULTS The linear calibration curves were obtained in the range of 0.25 - 50μg·L~(-1) in plasma.The lower limit of quantification was 0.25μg·L~(-1).The inter- and intra-day precision(RSD) were both below 11%calculated from QC samples.The linear calibration curves were obtained in the range of 0.5 - 100μg·L~(-1) in esophagus.The lower limit of quantification was 0.5μg·L~(-1).The inter- and intra-day precision (RSD) were both below 10%calculated from QC samples.CONCLUSION The method is fast,simple,high-throughput, and highly sensitive,suitable for the trace-level determination of fluorouracil.