Pharmacokinetics and tissue distribution study of camellianin A and its major metabolite in rats by liquid chromatography with tandem mass spectrometry.

Camellianin A is a major active constituent of Adinandra nitida. A LC-MS/MS method for the determination of camellianin A and its metabolite (camellianin B) in rat plasma and tissues was developed and applied to a pharmacokinetics and tissue distribution study. Samples were separated on a Waters HSS T3 column with a mobile phase consisted of methanol and water (containing 0.1% formic acid). MS/MS detection was carried out on a triple-quadruple mass spectrometer under negative ESI mode. Pharmacokinetics study showed that camellianin A was rapidly eliminated with a t1/2 of 92.6±41.4h and CL of 3.19±0.471L/min/kg. Additionally, camellianin A showed a low oral bioavailability of 2.99% and a narrow tissue distribution; however, camellianin B was proved to have a wide tissue distribution with brain penetration. The data presented in this study provides useful information for the further applications of A. nitida and camellianin A.