摘要
Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4.6 mm ×150 mm) column and a mobile phase of methanol: 0.01 mol·L^-1ammonium acetate (60:40, V/V) were used to separate nifedipine, the detections was accuracy under atmosperic pressure electronic spray ionization (AP-ESI) mode and ion mass spectrum (m/z) of 314.9 [M+H]^+ for nifedipine, and 320.8 [M+H]^+ for lorazepam (Internal Standard, IS). Results The linear range of nifedipine was 0.3 - 80 ng·mL^-1 ( r = 0.9997), and the limit of quantitation (LOQ) was 0.3 ng·mL^-1. The nifedipine pharmacokinetic parameters after a single dose of 20 mg nifedipine sustained-release tablets test (T) or reference (R) were as the followings, t1/2 (6.73 ± 2.00) h and (7.04 ± 2.18) h, Tmax (4.28 ± 0.70) h and (4.48 ± 0.70) h, Cmax(39.66 ± 10.58) ng·mL^-1 and (40.19 ± 10.97) ng·mL^-1, AUC0-36 (391.63 ± 108.55) ng·mL^-1·h and (387.57 ± 121.51) ng·mL^-1·h, and AUC0-∞ (408.28 ± 121.16) ng·mL^-1·h and (406.15 ± 133.13) ng·mL^-1·h. The relative bioavailability of nifedipine sustained-release tablets (test) was (103.02 ± 13.93) %. Conclusion LC-MS method for the determination of concentrations of nifedipine in human plasma was sensitive and accurate, and could be used in nifedipine bioavailability and pharmacokinetic studies.
目的建立HPLC-MS法硝苯地平血浓度测定方法,评价硝苯地平缓释片的药动学特点。方法固定相XB-C18(5μm,150mm×4.6mm,Agilent1100SeriesLC/MSD高效液相色谱/质谱仪;流动相甲醇:0.01mol·L–1醋酸铵溶液(60:40,V/V),0.40μm微孔滤膜过滤,在线脱气;流速1.0mL·min–1;柱温25°C;进样量10L。离子源:AP-ESI,正离子模式,雾化电压50psi,保护气13.0L·min–1N2,毛细管电压4000V,碎片电压为110V。SIM离子采集方式,采集离子(m/z)硝苯地平314.9[M+H]+,内标劳拉西泮320.8[M+H]+。结果硝苯地平线性范围0.3~80ng·mL–1,最低检出浓度为0.3ng·mL–1。硝苯地平试验制剂和参比制剂t1/2分别为6.73±2.00h和7.04±2.18h,Tmax分别为4.28±0.70h和4.48±0.70h,Cmax分别为39.66±10.58ng·mL–1和40.19±10.97ng·mL–1,AUC0~36分别为391.63±108.55ng·mL–1·h和387.57±121.51ng·mL–1·h,AUC0–∞分别为408.28±121.16ng·mL–1·h和406.15±133.13ng·mL–1·h,试验制剂硝苯地平缓释片相对生物利用度F为103.02±13.93%。结论HPLC-MS法测定硝苯地平血浓度实用、可行,适用于常规硝苯地平药代动力学研究。