Pharmacokinetic Study of Apigenin in Rat after Oral and Intravenous Administration

Apigenin is a flavonoid compound widely found in various fruits, vegetables and Chinese herbal medicines. It has the highest content in celery. Apigen has anti-oxidation, hypoglycemic, hypolipidemic and anti-cancer effects. In this study, we used UPLC-MS/MS to detect apigenin in rat plasma, and investigated its pharmacokinetics in rats. Buddleoside was utilized as an internal standard (IS), and acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC BEH C18 column using mobile phase of acetonitrile- 0.1 % formic acid with gradient elution. Electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied. The results indicated that within the range of 1-2000 ng/mL, linearity of apigenin in rat plasma was acceptable (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Intra-day and inter-day precision RSD of apigenin in rat plasma were lower than 15%. Accuracy range was between 92.5 and 109.0 %, and matrix effect was between 102.5 and 107.1%. The method was successfully applied in the pharmacokinetics of apigenin in rats after oral and intravenous administration. The absolute bioavailability of the apigenin was 9.0% in rats.