摘要
An efficient and sensitive ion-pair HPLC-UV method using atenolol as internal standard （IS） was developed and validated for the determination of metformin in the plasma of diabetic rats. Plasma samples were deproteinated with 10% （v/v） perchloric acid. Separation was achieved on a UltimateTM AQ-C18 column （250 mm×4.6 mm, 5 μm） with a mobile phase （pH 5.05） composed of acetonitrile-water （31：69, v/v, containing 0.002 M sodium dodecyl sulfate, 0.0125 M potassium dihydrogen phosphate, 0.015 M triethylamine） at a flow rate of 1.0 mL/min. The calibration curve was linear （r〉0.994） between 7.5 and 4000 ng/mL. The lower limit of quantification （LLOQ） was 7.5 ng/mL. The precision was validated and the relative standard deviation was in the range of 1.87% to 15.70%; the accuracy was between 93.98%-106.89%. The mean recoveries were 95.40% and 95.31% for metformin and IS, respectively. The relative error （RE） of stability at different storage conditions was within ±9.00%. This method was used to determine the concentration-time profile of metformin in diabetic rat plasma following an oral administration of metformin at the dose of 10 mg/kg. Our results indicated that ion-pair HPLC-UV method using UltimateTM AQ-C18 column was effective for the pharmacokinetic studies of high polarity compounds like metformin.
本研究建立并验证了测定糖尿病大鼠血浆中二甲双胍浓度的高效液相色谱方法,以阿替洛尔为内标,加入10%高氯酸沉淀蛋白来制备血浆样品。色谱条件:AQ-C18极限色谱柱(250mm×4.6mm,5μm),流动相(pH5.05)为乙腈-水(31:69,v/v,水相中含有0.002M十二烷基磺酸钠,0.0125M磷酸二氢钾,0.015M三乙胺),流速1.0mL/min。二甲双胍在7.5-4000ng/mL范围内具有良好的线性关系(r>0.994),最低检测限(LLOQ)为7.5ng/mL,描述精密度的相对标准偏差(RSD)范围为1.87%-15.70%,准确度为93.98%-106.89%。二甲双胍和内标的回收率分别为95.40%和95.31%。不同实验条件下质控样品的稳定性相对偏差范围在±9.00%之内。该方法成功地运用到糖尿病大鼠单剂量灌胃10mg/kg二甲双胍后的药代动力学研究中,结果显示本研究采用AQ-C18极限色谱柱建立的离子对色谱法对强极性化合物如二甲双胍具有良好的分离效果。
基金
National Integrity Innovational Technology Platform of New Drug and Research and Development (Grant No.2009ZX09201-010)
Innovation Team of Ministry of Education(Grant No. BMU20110263)
