RESUMEN
Objective To develop and validate a LC-MS/MS method for determination of rhoifolin in rat plasma and investi?gate its pharmacokinetic properties after intravenous administration to rats. Methods The analyte was isolated from rat plasma by liq?uid-liquid extraction with ethyl acetate. Separation was performed on a Phenomenex C8 column(30 mm×2.00 mm,3μm)with gradient elution using water-methanol as mobile phase. Electrospray ionization(ESI)was adopted in the negative ion mode for multiple reaction monitoring(MRM). The mass transitions were m/z 577.6→269.1 for rhoifolin,and m/z 271.0→151.0 for naringenin(internal stan?dard),respectively. Results The method showed good linearity over the range of 1-2000μg/L. Intra and inter-day precisions were both less than 10%,the relative error was within ± 7%. The extraction recoveries of three concentrations (low,middle and high) ranged from 86.8%to 91.0%. Main pharmacokinetic parameters were calculated by DAS 2.0. AUC0-t was(72627.8± 18067.9)μg·min/L, t1/2 was(52.1±14.3)min and CLz was(0.07±0.02)L/(min·kg). Conclusion The established LC-MS/MS method is specific and sensi?tive,and can be applied to pharmacokinetic study of rhoifolin. The pharmacokinetic parameters show that rhoifolin is eliminated rapid?ly in rats.