液相色谱-串联质谱联用测定人血浆中伪麻黄碱、O-去甲基右美沙芬和苯海拉明的浓度

 目的建立同时测定人血浆中伪麻黄碱、苯海拉明和O-去甲基右美沙芬的液相色谱-串联质谱方法。方法血浆中加入内标酚妥拉明后,进行固相萃取,以甲醇-0.5%甲酸水溶液(55∶45)为流动相,经C₁₈柱分离后;采用三重四极杆串联质谱,电喷雾离子源(ESI),以正离子多反应监测(MRM)方式进行定量分析,用于监测的离子为m/z 166.4→m/z 115.2(伪麻黄碱),m/z258.2→m/z157.1(O-去甲基右美沙芬),m/z256.2→m/z167.2(苯海拉明),m/z282.2→m/z212.2(内标,酚妥拉明)。结果线性范围为伪麻黄碱1.0～200μg·L^-1(r=0.9993),O-去甲基右美沙芬为0.05～10μg·L^-1(r=0.9991),苯海拉明为1.0～200μg·L^-1(r=0.9988);提取回收率为伪麻黄碱在67.4%～73.4%之间,O-去甲基右美沙芬在74.6%～75.7%之间,苯海拉明在81.9%～83.9%之间,日内、日间RSD均小于6.2%,伪麻黄碱、苯海拉明和O-去甲基右美沙芬的最低定量浓度分别为1.0,1.0和0.05μg·L^-1。结论该方法专属性强、灵敏度高、准确,适用于伪麻黄碱、O-去甲基右美沙芬、苯海拉明的临床药动学研究。

Simultaneous Determination of Pseudoephedrine,Dextrorphan and Diphenhydramine in Human Plasma by LC-MS/MS

OBJECTIVE To develop a LC-MS/MS method for the simultaneous determination of pseudoephedrine,dextrorphan and diphenhydramine in human plasma. METHODS After phentolamine as the internal standard was added,the plasma samples were processed on solid phase extraction(SPE),then analyzed on a C₁₈ column. The mobile phase was composed of methanol-0.5% formic acid (55∶45). Electrospray ionization source (ESI) was applied and operated in positive ion mode. Multiplereaction monitoring were used with mass transition of m/z 166.4→m/z 115.2,m/z 258.2→m/z 157.1,m/z 256.2→m/z 167.2 and m/z 282.2→m/z 212.2 for pseudoephedrine,dextrorphan,diphenhydramine and IS,respectively. RESULTS Standard curves were linear in the range of 1.0-200 μg·L^-1(r=0.999 3) for pseudoephedrine,0.05-10 μg·L^-1(r=0.999 1) for dextrorphan and 1.0～200 μg·L^-1 (r=0.998 8) for diphenhydramine. The extraction recoveries were 67.4%-73.4% for pseudoephedrine,74.6%-75.7% for dextrorphan and 81.9%-83.9% for diphenhydramine. The RSDs of intra-day and inter-day assays were all less than 6.2%. The quantification limits of the method for pseudoephedrine diphenhydramine and dextrorphan were 1.0,1.0 and 0.05 μg·L^-1,respectively. CONCLUSION The method was proved to be specific,sensitive and accurate,and suitable for clinical pharmacokinetic studies of pseudoephedrine,dextrorphan and diphenhydramine.