摘要
A new high-performance liquid chromatography （HPLC） method for the quantitative determination of sitagliptin in rat plasma was developed and validated for pharmacokinetics study. The plasma was spiked with the internal standard （hydrocortisone, IS）, treated with sodium hydroxide, and extracted with ethyl acetate. The extracted analyte was injected into an Agilent Zorbax Extend-C18 column （250 mm×4.6 mm, 4 μm） maintained at 30℃ and monitored at 267 nm. The mobile phase consisting of methanol-water （60：40, v/v, containing 10 mM Tris and 10 mM triethylamine） was titrated to pH 9.0 using 1 mol/L hydrochloric acid. The flow rate was 1.0 mL/min. The method showed high specificity. Calibration curves of the peak area ratio of each analyte/IS versus sitagliptin concentration were linear in the range of 0.75-100.0μg/mL （r〉0.9957）. The lower limit of quantification （LLOQ） was 0.75 μg/mL. The intra-day and inter-day coefficient of variation was lower than 10%. The accuracy （relative recovery） at three levels was 105.3% （0.75 μg/mL）, 99.8% （10.0 μg/mL） and 99.0% （100.0 μg/mL）. The extraction recovery was 81.5%, 82.4% and 84.5% at the concentrations of 0.75, 10.0 and 100.0 μg/mL, respectively. The short-term, long-term, freeze-thaw storage stability of plasma samples and the stability of standard solutions were satisfactory. This HPLC method is suitable for determining the concentration of sitagliptin in rat plasma and it was applied to determine the concentration-time profiles of sitagliptin in rat plasma following oral administration of sitagliptin.
本研究建立并验证了测定大鼠血浆中磷酸西他列汀浓度的高效液相色谱法,并在大鼠体内进行药动学研究。血浆中的药物和内标(氢化可的松)由乙酸乙酯萃取。所用色谱柱为Agilent Zorbax Extend-C18柱(250mm×4.6mm,4μm),进样量为20μL,检测波长为267nm,柱温为30oC。流动相为甲醇–水(60:40,内含10mMTris和10mM三乙胺,并用1M盐酸调至pH9.0)。流速为1.0mL/min。色谱峰具有良好的特异性。在0.75–100.0μg/mL范围内具有良好的线性关系(r>0.9957)。定量下限为0.75μg/mL。日间,日内精密度均小于10%。在0.75,10.0,100.0μg/mL的相对回收率为105.3%,99.8%,99.0%,提取回收率分别为81.5%,82.4%,84.5%。样品的稳定性良好。运用该方法测定了大鼠口服磷酸西他列汀水溶液后的血药浓度,说明本方法可用于药物动力学的研究。
基金
National Integrity Innovational Technology Platform of New Drug and Research and Development (Grant No. 2009ZX09301-010)
National Fund for Talent Training in Basic Science
