Aim: To establish a LC-MS(n) method for the identification of anisodamine and its metabolites in rat feces.
Methods: Feces samples were collected after single administration of 25 mg x kg(-1) anisodamine to rats, and dipped in water for 1 h. Samples were then 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, v/v) and detected by LC-MS". Identification of the metabolites and elucidation of their structures were performed by comparing their changes in molecular masses (deltaM), retention-times and full scan MS(n) spectra with those of the parent drug and blank feces.
Results: The parent drug and its seven metabolites (6beta-hydroxytropine, nor-6beta-hydroxytropine, aponoranisodamine, apoanisodamine, noranisodamine and hydroxyanisodamine, tropic acid) were found in rat feces.
Conclusion: This method is sensitive, rapid, simple, effective, and suitable for the rapid identification of drug and its metabolites in biologic samples.