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 deprotei...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.展开更多
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)
文摘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.