HPLC法测定血浆中左氧氟沙星及其人体药动学研究

目的 建立人血浆中左氧氟沙星的HPLC-UV测定法,测定健康志愿者口服左氧氟沙星片200 mg后的药代动力学参数,并评价其与参比制剂的生物等效性.方法 血浆样品以20%高氯酸沉淀后,直接取上清液进行PHLC分析,流动相为水：乙腈：三乙胺：冰乙酸（81∶19∶0.5∶1,v/v/v/v）.20名志愿者交叉口服左氧氟沙星片试验和参比制剂200mg,用HPLC法测定血药浓度,计算主要药代动力学参数及相对生物利用度,以判断其生物等效性.结果 在0.05～5μg·mL^-1范围内左氧氟沙星峰面积与浓度呈良好的线性关系,左氧氟沙星片受试制剂和参比制剂的t1/2分别为（6.46±0.77）h和（6.58±1）h,峰浓度分别为（2.74±0.75）μ g·mL^-1和（2.55±0.54）μg·mL^-1,达峰时间分别为（0.9±0.3）h和（1.0±0.5）h.以AUC0-24计算的供试制剂相对生物利用度为（105.55±12.30）%.结论 本文建立的HPLC测定方法灵敏、准确、简便,药动学统计数据表明两种左氧氟沙星片生物等效.

Determination of levofloxacin in plasma by HPLC and its pharmacokinetics study

Objective To develop an HPLC-UV assay for the determination of levofloxacin in human plasma, and evaluate the pharmacokinetics and bioequivalence. Methods After being deproteined by perchloric acid (20%, v/v), samples were separated by HPLC on a reversed-phase C18 column with a mobile phase of water-acetonitrile- triethylamine-acetic acid (81∶19∶0.5∶1, V/V/V/V)and with the flow rate 1.0 ml · min-1. A randomized crossover design was performed in 20 healthy volunteers. In the two study periods, a single dose of two tablets was administered to each volunteer. Results The calibration curve was linear among the range 0.05 ～ 5 μg·ml-1 T1/2. Tmax and Cmax were (6.46 ± 0.77) h, (0.9 ± 0.3) h and ( 2.74 ± 0.75 ) ug/L for the test tablet and (6.58 ± 1) h, (1.0 ± 0.59) h and (2.55 ± 0.54)ug/L for the reference tablet, re spectively. The relative bioavailability of the test tablet was(105.55 ± 12.30)%. The results of variance analysis and two one-sided t-test showed that there was no significant difference between the two preparations in the AUC and Cmax. Conclusion The assay was proved to be sensitive,accurate and convenient. The two preparations were bioequivalent.