水溶性紫杉醇多聚谷氨酸偶合物和紫杉醇在小鼠体内的组织分布比较

目的: 研究水溶性紫杉醇多聚谷氨酸偶合物(PP)在小鼠体内的组织分布,并与紫杉醇(PT)的组织分布特征进行比较,建立测定小鼠血浆及组织中PT的液相色谱-质谱/质谱(LC-MS/MS)方法。 方法: 小鼠尾静脉注射10 mg·kg^-1的PP和PT,于给药后不同时间采血及各组织,以多西紫杉醇为内标,PT用甲基叔丁基醚提取,在BetaBasic C₁₈色谱柱上以流动相乙腈-水-甲酸(65∶ 35∶ 0.1)分离,流速0.2 mL·min^-1;采用电喷雾离子化电离源,以选择反应监测方式进行正离子检测,用于定量分析的离子反应分别为m /z 854.2→286.1(PT)和m /z 808.3→527.2(多西紫杉醇)。 结果: 测定PT的线性范围为0.5~1000 ng·mL^-1,定量下限为0.5 ng·mL^-1,日内和日间精密度(RSD)分别在11.5%和13.1%以内,准确度分别在87.6%~103.3%和87.1%~109.5%,提取回收率为78.8%~97.7%。与PT相比,PP给药后PT在组织中分布更广,驻留时间更长,提高了AUC_{组织/血浆}比值。 结论: LC-MS/MS方法速度快、灵敏度高、专属性好。与PT相比,PP改变了PT的组织分布,有助于提高临床用药水平。

Objectives: To investigate tissue distribution of water-soluble poly glutamic acid -paclitaxel conjugate (PP) in mice and compare to that of paclitaxel (PT), and establish liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of paclitaxel (PT) in plasma and tissues. Methods: Plasma and tissues were collected at designated time points after mice were intravenously administered with PP or PT at a single dose of 10 mg·kg^-1. PT and docetaxel as an internal standard were extracted from plasma and tissues using tert-butyl methyl ether and separated on a BetaBasic C₁₈ column using mobile phase of acetonitrile-water-formic acid (65∶ 35∶ 0.1,v/v/v) at a flow rate of 0.2 mL·min ^-1. At positive electrospray ionization mode, selected reaction monitoring of the precursor-product ion transitions m/z 854.2→286.1 for PT and 808.3→527.2 for docetaxel was used for quantification. Results: The linear calibration curve was obtained in a concentration range of 0.5-1000 ng·mL^-1 with a lower limit of quantification of 0.5 ng·mL^-1. Intra- and inter-day precision was less than 11.5% and 13.1%, respectively. Intra- and inter-day accuracy fell in the ranges of 87.6%-103.3% and 87.1%-109.5%, respectively. The extraction recovery was between 78.8% and 97.7%. Compared to PT, PT released from PP was distributed at tissues with larger MRT and AUC_{tissue/plasma}. Conclusion: The method is rapid, sensitive, specific. As compared with PT, tissue distribution of PT from PP is altered, which is helpful to improve clinical efficacy of PT.