OBJECTIVETo develop a LC-MS/MS method for determination of astragalin in rat plasma and study its pharmacokinetics in rats.

METHODSThe analytical column was packed with ZORBAX SB-C18, and the mobile phase was methanol-water containing 10 mmol/L ammonium acetate-formic acid (80:20:0.15, V/V/V). Quercetin was used as the internal standard (IS). Multiple reaction monitoring (MRM) mode was employed, and the transition of m/z was m/z 449.1→m/z 287.1 for astragalin, and m/z 301.1→m/z 151.1 for IS.

RESULTSA good liner relationship was obtained within the range of 1.00-1000 ng/ml (r(2)=0.9929), and the lower limit of quantification of astragalin was 1.00 ng/ml in rat plasma. The extraction recoveries were all above 93%. After oral administration of astragalin, the maximum plasma concentration of astragalin was 231.1∓67.3 ng/ml and the time to reach this value was 0.5∓0.1 h, with a half-life of 3.9∓1.3 h and an AUC of 782.6∓152.8 ng·h/ml.

CONCLUSIONThe method is highly sensitive, selective and rapid for determination of the concentration of astragalin in rat plasma to facilitates the study of its pharmacokinetics.