Simultaneous Determination and Pharmacokinetics of Three Steroidal Alkaloids in Rat Plasma by UHPLC–MS After Oral Administration of Three Different Preparations of <i>Fritillaria ussuriensis</i> Maxim Bulb

Pharmacokinetic studies can provide a method for optimizing preparations. In this study, three most abundant compounds from Fritillaria ussuriensis bulb were isolated, and a selective, sensitive new analytical method was developed. This method aims for the simultaneous determination of peimisine-3-O-β-D-glucopyranoside (1), karelinine (2), and peimisine (3) in rat plasma after oral administration of F. ussuriensis bulb powder (FUP), total alkaloid extract (FUE), and its nanodispersion preparation (FUN) using UHPLC-MS/MS. The chromatographic separation was performed on the UHPLC Waters BEH C18 column. The pharmacokinetic results showed that among three groups, 1 and 3 exhibited slower absorption and elimination processes when rats were orally administered with FUP and FUE. Steroidal alkaloids 1 ~ 3 from FUN reached peak concentrations within 3 h. Compared with FUE and FUP, the absorption and elimination rates were accelerated, and the area under the curve (AUC) significantly increased. In this study, the pharmacokinetic characteristics of 1 ~ 2 were first detected and calculated parameters in rat plasma when orally administered in different dosage forms. And a new nanodispersion preparation, FUN, has been developed. FUN has better absorption efficiency and higher bioavailability compared with traditional powder oral administration.