Key Lab of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, No. 24 Tongjiaxiang Street, Nanjing 210009, China.
J Pharm Biomed Anal. 2011 Jul 15;55(5):1157-62. doi: 10.1016/j.jpba.2011.04.007. Epub 2011 Apr 15.
A sensitive and simple liquid chromatography-mass spectrometry (LC-MS) method has been developed and validated for the quantification of solamargine, a steroidal glycoalkaloid, in rat plasma. Vincristine was selected as the internal standard. Sample preparation involved simple liquid-liquid extraction by ethyl acetate with high efficiency. The chromatographical separation was performed on a Shimadzu C(18) column (150mm×2.0mm, 5μm) with a gradient elution of acetonitrile and 0.02% (v/v) formic acid. The elutes were detected under positive electrospray ionization (ESI) and the target analytes quantified by selected ion monitoring (SIM) mode. The method was sensitive with the lowest limit of quantitation (LLOQ) at 0.5ng/mL in 50μL of rat plasma. Good linearity (r(2)=0.9996) was obtained covering the concentration of 0.5-2000.0ng/mL. The intra- and inter-day assay precision ranged from 2.87 to 3.60% and 0.52 to 6.81%, respectively. In addition, the stability, extraction recovery and matrix effect involved in the method were also validated. The practical utility of the aforementioned method was successfully confirmed in the pharmacokinetic evaluation of solamargine in Sprague-Dawley rats after intravenous administration.
一种灵敏而简单的液相色谱-质谱（LC-MS）方法已经建立并验证，用于定量检测大鼠血浆中的甾体糖苷生物碱甾体苦马豆素。长春新碱被选为内标。样品制备采用乙酸乙酯进行简单的液液萃取，效率高。色谱分离在 Shimadzu C(18)柱（150mm×2.0mm，5μm）上进行，采用乙腈和 0.02%（v/v）甲酸的梯度洗脱。采用正电喷雾电离（ESI）进行洗脱检测，通过选择离子监测（SIM）模式定量分析目标分析物。该方法具有较高的灵敏度，在 50μL 大鼠血浆中的最低定量下限（LLOQ）为 0.5ng/mL。在 0.5-2000.0ng/mL 的浓度范围内，具有良好的线性关系（r(2)=0.9996）。日内和日间测定的精密度范围分别为 2.87-3.60%和 0.52-6.81%。此外，还验证了该方法涉及的稳定性、提取回收率和基质效应。上述方法在静脉注射后评价 Sprague-Dawley 大鼠体内甾体苦马豆素的药代动力学方面得到了成功的应用。
