用LC-MS/MS法测定人唾液中维生素E醋酸酯的浓度

Determination of the concentration of vitamin E acetate in human saliva by LC-MS/MS method

目的：建立LC-MS/MS法测定人唾液中维生素E醋酸酯的浓度。方法：在唾液中加入内标氘9-维生素E醋酸酯,用甲醇直接沉淀蛋白质法处理样品,Venusil XBP C8柱进行色谱分离;流动相为甲醇,流速0.8ml/min,柱温45℃,进样体积10μl;正离子多反应监测模式,离子通道分别为m/z473.4→207.4（维生素E醋酸酯）和482.4→216.4（氘9-维生素E醋酸酯）。结果：维生素E醋酸酯线性范围为5~5000μg/L,提取回收率为81.9%~93.9%,批内、批间精密度RSD均〈10%,内标校正基质因子为0.99~1.0。结论：本方法操作简便,专一性好,灵敏度高,适用于维生素E醋酸酯补充剂临床用量监测,为药动学和药效学研究提供了参考。

Objective： To establish a LC-MS/MS method for the concentration determination of vitamin E acetate in human saliva. Methods： After spiking isotope-labeled internal standards （d9-vitamin E acetate） into saliva,a direct protein precipitation was processed with methanol. Vitamin E acetate was separated on Venusil XBP C8 column with a mobile phase of methanol. The flow rate was 0.8 ml/min and column temperature was kept at 45 ℃. The injection volume was 10μl. The protonated ions of analytes were detected in positive ionization through multiple reaction monitoring mode. The mass transition pairs of m/z 473.4→207.4 and 482.4→216.4 were used to detect vitamin E acetate and d9-vitamin E acetate, respectively. Results： Vitamin E acetate displayed good linearity within the ranges of 5-5000 μg/L. The extraction recovery rates were 81.9%-93. 9%. The intra-batch and inter-batch relative standard deviation（RSD） was〈 10 %. And the internal standard （IS）-matrix effect factors were within the ranges of 0.99-1.0. Conclusion： The established LC-MS/MS method is simple, specific and sensitive, and could be used to monitor the supplement of vitamin E acetate clinically and provide reference for pharmacokinetie and pharmacodynamic researches of vitamin E acetate.