电喷雾串联质谱法检测大鼠粪样中的樟柳碱及其代谢物

 目的应用液相色谱-电喷雾串联质谱(LC-MSⁿ)法检测樟柳碱及其大鼠粪样中的代谢物。方法收集灌胃20 mg樟柳碱的大鼠粪样,用水浸泡后,以乙酸乙酯萃取,采用甲醇-0.01%三乙胺水溶液(以甲酸调节pH 3.5)(60∶40)为流动相,0.2mL·min^-1流速,40℃柱温,以及离子源喷射电压5.0 kV,毛细管电压45 V,毛细管温度200℃,鞘气(N₂)流速40个单位等进行LC-MS及LC-MSn检测原药及其代谢物。和空白粪样及樟柳碱相比较,根据代谢物相对分子质量的变化(ΔMr)及其多级质谱数据,鉴定并阐述其结构。结果在服药后的大鼠粪样中发现5种代谢物,分别为莨菪品、去甲基莨菪品、去甲基樟柳碱、羟基樟柳碱以及樟柳酸等。结论该方法灵敏、快速、简便、可靠,适合于生物样品中的药物及其代谢物的快速鉴定。

Determination of Anisodine and Its Metabolites in Rat Feces by Tandem Mass Spectrometry

OBJECTIVE To identify anisodine and its metabolites in rat feces by combining liquid chromatography and tandem mass spectrometry(LC-MSⁿ).METHODS The feces were collected after a single administration of 20 mg anisodine to rats,and dipped in water for 1 h.Then,the samples were extracted by ethyl acetate.The pretreated samples were separated on a reversed-phase C₁₈ column using a mobile phase of methanol-0.01% triethylamine(adjusted to pH 3.5 with formic acid)(60∶40) and detected by LC-MSⁿ.Identification of the metabolites and their structural elucidation were performed by comparing their changes in molecular masses(ΔM_r),retention-times and full scan MSⁿ spectra with those of the parent drug and blank feces.RESULTS The results revealed that the parent drug and its five metabolites(scopine,norscopine,α-hydroxytropic acid,noranisodine and hydroxyanisodine) existed in rat feces.CONCLUSION This method is sensitive,rapid,simple and accurate,and it is suitable to the rapid identification of drug and its metabolites in biologic samples.