【作者】 杨敏； 王广基； 王素军； 李晓天； 徐宇平； 曹国宪； 叶文才；

【Author】 YANG Min, WANG Guang-ji,WANG Su-jun, LI Xiao-tian, XU Yu-ping, CAO Guo-xian, YE Wen-cai ( Jiangsu Institute of Nuclear Medicine, Key Laboratory of Nuclear Medicine, Wuxi 214063, China; Research Center of pharmacokinetics, China Pharmaceutical University, Nanjing 210009,China; Department of Phytochemistry, China Pharmaceutical University, Nanjing 210009, China)

【机构】 江苏省原子医学研究所卫生部核医学重点实验室； 中国药科大学药代中心； 中国药科大学天然药化教研室；

【摘要】 目的:建立测定小鼠血浆中23-羟基白桦酸的液相色谱-质谱联用法(LC-MS)。方法取血浆,加入内标物柠檬苦素,经二氯甲烷-水(6:1)提取后,40℃水浴中氮气吹干,残渣用甲醇溶解,进行LC-MS测定。色谱柱为Intersil C8(2．1mm×250mm, 3．5 μm):70％乙腈为流动相(其中三乙胺为0．05％):流速0．2mL·min-1;柱温30℃;电喷雾离子源(ESI),负离子检测(23-HBA, m／z471;柠檬苦素,m／z469)。结果 23～羟基白桦酸的线性范围为10～1000 ng·mL-1(r=0．9998),最低定量检测限为0．05pg(10 ng／mL,5 μL进样),方法平均回收率>88％,日内、日间精密度(RSD)均小于10％。小鼠血浆样品-20℃放置至少稳定三周。结论本方法专属性强,灵敏度高,线性范围宽,操作简便,适用于药动学研究。更多还原

【Abstract】 OBJECTIVE To develop a sensitive and specific LC/MS method for the determination of 23-Hydroxybetulinic acid in mouse plasma. METHODS 23-hydroxybetulinic acid and the internal standard limonin were extracted by liquid-liquid extraction. The organic layer was blowed by N2 to dryness at 40 ℃. The residue was reconstituted in methanol. The LC-MS method was performed on an Intersil C8 column (2.1mm × 250mm, 3.5μm). The mobile phase consisted of 70% acetonitrile and 0.05% triethylamine. The flow rate was at 0.2 mL ·min-1.The temperature of column was 30 ℃. Negative ion electrospray ionization (ESI) was used to form deprotonated molecules at m/z 471 of 23-hydroxybetulinic acid and 469 of the internal standard limonin. RESULTS The linear calibration curve was observed in the concentration range of 10-1000 ng·mL-1(r=0.9998). The limit of quantitation of 23-hydroxybetulinic acid was 0.05 pg (0.11 fmol,10ng/mL, 5μL injection volume) injected on-column. The relative recoveries were more than 88%.The inter and intra-day precision (RSD) were below 8.0%. 23-hydroxybetulinic acid was stable in plasma samples at -20 ℃ for at least 3 weeks. CONCLUSION The method was proved to be convenient, sensitive, rapid and suitable for pharmacokinetics study.更多还原