目的:建立反相高压液相色谱法测定亚叶酸钙片剂和胶囊含量的方法,同时检查其有关物质,并进行稳定性考察.方法:采用Lichrosorb C18色谱柱,以乙腈∶10 mmol*L-1醋酸钠-三乙胺缓冲液(冰醋酸调pH至5.5)(4∶96)为流动相,流速1.2 mL*min-1;检测波长286 nm,柱温为常温.结果:在色谱条件下,亚叶酸钙制剂的分析不受辅料和降解产物的干扰,其检测限为0.04 μg,定量限为0.12 μg,在12.5～150 mg*L-1范围内线性关系良好(r=0.9998),加样回收率为99%～101%,日内、日间RSD<3.0%.结论:本法灵敏准确,方便实用.

A sensitive and reliable high-performance liquid chromatographic (HPLC) method, using a solid-phase extraction (SPE), was developed and validated for determination of leucovorin (LV) in human plasma. Plasma sample was extracted by using a Sep-Pak cartridge which could be renewable. The sample was analyzed by HPLC with UV detection at 286 nm. The method was shown to perform selectively and sensitively for LV. The main metabolite of LV, 5-methyltetrahydrofolic acid, and endogenous substances in plasma did not show any interference in the analysis. The limit of detection was 10 ng/mL for LV in plasma and the linear range was 50-1500 ng/mL in plasma. The relative standard deviation (RSD) of intra-day and inter-day assays was 2.8-6.1% and 2.4-5.3%, respectively. The extraction recoveries of LV in plasma were over 90%. The method was proved to be applicable to the pharmacokinetic study of LV in healthy volunteers after a single oral administration (75 mg). The pharmacokinetic parameters and relative bioavailability were investigated for domestic LV tablet and capsule vs an imported tablet.

在人类生活水平不断提高的今天，人类对医药事业的需求不断提高，对治疗和保健有了更迫切的要求。

Objective:A HPLC method was developed for the determination of clinafloxacin in rat plasma.Methods:After adding the internal standard ciprofloxacin,the plasma samples were extracted by an Oasis pretreatment cartridge and determined by HPLC.Chromatography was performed on a Lichrosorb C\-\{18\} column (150 mm×4 6 mm,5 μm) with a mobile phase consisting of acetonitrile-0 05 mol·L\+\{-1\} citric acid-triethylamine (pH 2\^5)(20∶80),at a flow rate of 1 mL·min\+\{-1\}.The detection wavelength was 300 nm.Results:The linear range was 0 03～10 μg·mL\+\{-1\} ( r =0 999 8).The minimal detectable concentration of this method was 0\^02 μg·mL\+\{-1\}.The extraction recovery of this method ranged from 92\^6% to 95\^8%.The plasma concentraction-time curves of clinafloxacin after a single oral dose 50 mg·kg\+\{-1\} in 6 rats were studied by this method.Conclusions:This method has adequate accuracy,precision and sensitivity to determine plasma concentrations in pharmacokinetic studies.

克林沙星(clinafloxacin)是目前正在研制的第四代喹诺酮类广谱抗菌药，其抑菌作用是通过抑制细菌的DNA促旋酶而实现的。克林沙星对肺炎球菌、粪肠球菌、金葡菌、脆弱拟杆菌及绿脓杆菌的抗菌活性优于环丙沙星、左氧氟沙星及司帕沙星[1]，因而在临床上具有较高的使用价值[1]。有文献报道用反相离子对色谱法[2]和手性高效液相色谱法[3]进行克林沙星在人体内的药动学研究，但未报 道具体分析方法，也未对方法进行评价。我们建立了以固相萃取为前处理的反相高效液相色谱法，并测定3个剂量克林沙星在大鼠体内的药代动力学参数。