固相萃取LC-MS/MS法测定人血浆中曲匹地尔浓度及胶囊剂与片剂的生物等效性研究

目的：建立固相萃取液相色谱串联质谱法测定人血浆中曲匹地尔浓度，并应用于曲匹地尔胶囊剂与曲匹地尔片剂在中国健康受试者的生物等效性研究。方法：血浆样品经固相萃取后，采用LC-MS/MS进行测定。色谱柱为MG S-5 C₁₈分析柱（50 mm×4.6 mm，5 μm），流动相为甲醇-10 mol·L^-1甲酸铵溶液（80：20），流速0.4 mL·min^-1。苯海拉明为内标。采用四极杆质谱检测器大气压电喷雾离子源（APCI），正离子检测，以多反应离子监测（MRM）扫描方式进行监测，用于定量分析的离子为m/z 206.0 →109.0（曲匹地尔）和m/z 256.1→167.1（内标）。20名男性健康志愿者交叉口服受试制剂和参比制剂，计算主要药动学参数及生物利用度，以判断其生物等效性。结果：血浆中曲匹地尔质量浓度在4.0~3 200 ng·mL^-1范围内线性关系良好（r=0.999 5），最低定量限为4.0 ng·mL^-1。受试制剂与参比制剂的主要药动学参数：C_max分别为（1 325.7±389.8）、（1 377.7±287.3） ng·mL^-1，T_max分别为（0.75±0.65）、（0.68±0.30） h，t_1/2分别为（1.3±0.3）、（1.3±0.3） h，AUC_{0-12 h}分别为（4 276.3±1 376.0）、（4 060.9±123.7） ng·mL^-1·h。以AUC_{0-12 h}计算，受试制剂相对生物利用度为（105.8±17.3）%。结论：该方法简便、快速，灵敏度高，可用于测定人血浆中曲匹地尔浓度；曲匹地尔胶囊剂与曲匹地尔片剂生物等效。

Objective: To develop a solid-phase extraction LC-MS/MS method for determination of trapidil in human plasma,and to study the bioequivalence of trapidil capsules and trapidil tablets in Chinese healthy volunteers.Methods: Using diphenhydramine as internal standard,the plasma samples were extracted with solid phase extraction(SPE). The MG S-5 C₁₈ column(50 mm×4.6 mm,5 μm) was used,the mobile phase consisted of methanol,10 mol/·mL^-1 ammonium formate solution(80:20),flow rate was 0.4 mL·min^-1. Atmospheric pressure chemical ionization(APCI) source was applied and operated in the positive multiple reaction monitoring(MRM) mode. Target ions were at m/z 206.0→109.0 for trapidil and m/z 256.1→167.1 for internal standard. In a randomized cross-over study,20 healthy male volunteers were divided into two groups,and were administered respectively with test and reference preparations 50 mg under fasting conditions.Results: The calibration curve was linear within the range of 4.0-3 200 ng·mL^-1(r=0.999 5) with the lower limit of quantitation(LLOQ) 4.0 ng·mL^-1. The pharmacokinetic parameters of test and reference preparations under fasting conditions were as follows:C_max were(1 325.7±389.8) and(1 377.7±287.3) ng·mL^-1;T_max were(0.75±0.65) and(0.68±0.30) h;t_1/2 were(1.3±0.3) and(1.3±0.3) h;AUC_{0-12 h} were(4 276.3±1 376.0) and(4 060.9±123.7) ng·mL^-1·h,respectively. The relative bioavalability of trapidil capsules was(105.8±17.3)%.Conclusions: The method is robust,fast and sensitive,and it is suitable for determination of trapidil in human plasma. Trapidil capsules and trapidil tablets are bioequivalent.