人血浆中非那雄胺的HPLC-MS法测定

目的建立人血浆中非那雄胺的HPLC-MS测定法,以测定志愿者口服非那雄胺片剂后的血药浓度,并对供试制剂和参比制剂的生物等效性进行评价。方法血样经0.1 mol·L^-1NaOH碱化后用重蒸乙酸乙酯提取,进行HPLC-MS分析,色谱柱为Hypersil ODS （5 μm,250 mm×4.6 mm）,流动相为甲醇-水 (85∶15),内标为甲地孕酮,检测离子为m/z 395（非那雄胺）、m/z 407(内标),裂解电压为120 V。20名健康志愿者交叉口服供试片和参比片,计算主要药代动力学参数及相对生物利用度,以判断生物等效性。在1～200 μg·L^-1非那雄胺与内标峰面积比值与浓度线性关系良好（R=0.998 6）, 检测限为0.05　μg·L^-1,回收率为85.9%～98.7%。以AUC_0-24计算的非那雄胺片剂的相对生物利用度为(100±13)%。结论建立的分析方法灵敏、准确、简便。统计学结果表明两种制剂生物等效。

Determination of finasteride in human plasma by HPLC-MS

AIM: To develop an HPLC-MS assay for determination of finasteride in human plasma and to investigate the bioequivalence in healthy volunteers. METHODS: After alkalization with sodium hydroxide, plasma was extracted with ethyl acetate and separated using a C18 column with a mobile phase of methanol-water (85:15). LC-ESI-MS was performed in the selected ion monitoring (SIM) mode using target ions at m/z 395 for finasteride and m/z 407 for the IS. The fragmentor voltage was 120 V. A randomized crossover design was performed in 20 healthy volunteers. In the two study periods, a single 10 mg dose of each tablet was administered to each volunteer. RESULTS: Calibration curves were linear over the range 1-200 micrograms.L-1 (r = 0.9986). The limit of determination for finasteride in plasma was 0.05 microgram.L-1. The recovery of finasteride from plasma was in the range of 85.9%-98.7%. The results of variance analysis and two one-side t-test showed that there was no significant difference between the two formulations in the AUC and Cmax. CONCLUSION: The assay was proved to be sensitive, accurate and convenient. The two formulations were bioequivalent.