Pharmacokinetics and tissue distribution of oroxin B in rats using a validated LC–MS/MS assay

A highly sensitive LC–MS/MS method was developed to measure oroxin B in rat plasma and tissue homogenates. The analyte and IS were isolated from biological matrices by a simple protein precipitation followed by centrifugation. Detection was conducted by electrospray negative‐ionization mass spectrometry in selected‐reaction monitoring mode. The assay was linear in the concentration range 4.52–904 ng/mL with intra‐ and inter‐day precision of <14.41%. It was successfully applied to the pharmacokinetics and tissue distribution studies of oroxin B after an intravenous dose of 1.0 mg/kg in rats. The results would be useful for further development of oroxin B.