LC-MS法测定人血浆中利托君浓度

Determination of Ritodrine in Human Plasma by LC-MS

目的:建立以液-质联用(LC-MS)法测定人血浆中利托君浓度的方法。方法:色谱柱为Agilent Eclipse Plus C18,流动相为甲醇-水(95∶5,含0.02mol.L-1甲酸铵),流速为0.5mL·min-1,柱温为40℃,提取剂为乙酸乙酯-二氯甲烷(4∶1)。样品经电喷雾离子源正离子化后,通过三重四极杆串联质谱仪,采用选择反应监测(SRM)对利托君(m/z288.2→121.1)和内标多巴酚丁胺(m/z302.1→107.0)进行测定。结果:利托君血药浓度在0.25～100ng·mL-1范围内线性关系良好(r=0.9991),定量下限为0.25ng·mL-1。日内、日间RSD均<15%;方法回收率为98.00%～103.44%。结论:本方法灵敏、准确、重现性好、特异性强,适用于利托君的药动学研究。

OBJECTIVE： To establish an LC-MS method for the determination of the ritodrine content in human plasma. METHODS： The determination was performed on Agilent Eclipse Plus C18 column with the column temperature kept at 40℃. The mobile phase consisted of methanol- water （95 ： 5, containing 0.02 mol·L^-1 ammonium formate） with a flow rate of 0.5 mL·min^-1. The extraction agent was acetic ether - diehloromethane （4 ： 1）. A triple quad mass spectrometer system equipped with an electro spray ionization ion - trap source was used as the detector and operated in the positive ion model. Selected reaction monitoring （SRM） was employed to detect ritodrine （m/z 288.2→121.1） and the internal standard dobutamine （m/z 302.1→107.0） . RESULTS： The linear range of ritodrine was 0.25--100 ng·mL^-1（r = 0.999 1）, with the lower limit of quantification at 0.25 ng·mL^-1. Both the intra - day RSD and inter - day RSD were less than 15%. The methodological recovery was 98.00%- 103.44%. CONCLUSION： The method is sensitive, accurate, reproducible, specific and suitable for the pharmaceutical study of ritodrine.