反相离子对HPLC测定人血浆中二甲双胍研究

Determination of the content of metformin in human plasma by ion-pair RP-HPLC

目的建立一种快速、准确测定人血浆中盐酸二甲双胍含量的反相离子对HPLC方法。方法在血浆中加入盐酸二甲双胍标样及内标阿替洛尔，用乙腈除蛋白，离心后取上清液加二氯甲烷萃取乙腈，再次离心后，取上清液直接进样分析；色谱柱为Diamonsil C18（150×4．6mm，5μm），流动相组成：（0．01mol／L磷酸二氢钠＋0．0075mol／L十二烷基磺酸钠）（pH5．5）：乙腈（70：30），检测波长为235nm，柱温：30℃，流速为1．0mL／min，进样量为20μL。结果盐酸二甲双胍在0．05～4μg／mL的浓度范围内呈良好线性，r=0．9997，最低检测限为0．015μg／mL，方法回收率大于97．98％，萃取回收率大于89．35％，日间、日内变异系数均小于5％。结论该方法准确、快速、灵敏，可用于盐酸二甲双胍的治疗药物监测、人体内药代动力学及生物等效性研究。

Objective To establish a rapid and accurate method using ion pair RP-HPLC for quantification of metformin in human plasma. Methods Humah plasma sample was deproteinated with acetonitrile,and dichloromethane was used to extract metformin from the supernatant. The metformin and internal standard atenolol were separated with the Diamonsil （150×4.6mm, 5 μm） C18 column. The mobile phase consisted of acetonitrile - 0. 007 5mol/L sodium dodecyl sulphate and 0.01mol/L sodium dibydrogen phosphate [30 ： 70 （V ： V） ,pH 5.5],at a flow rate of 1.0mL/min. The detector was monitored at 235 nm. Results The calibration curve was linear（r=0. 9997） among the concentration range of 0.05--4μg/mL and and the limit of the quantitive detection was 0. 015μg/mL. The recovery of the method was 〉97.98 % and the extraction recovery was 〉89.35%. The coefficients of variation for inter-day and intra-day were both 〈5 %. Conclusion As an accurate,rapid and sensitive method, this assay can be used in the therapeutic drug monitoring,and the study of pharmacokinetic and bioavailability of metformin.