ABSTRACT
OBJECTIVE: To establish a HPLC method for the determination of serum concentration of caffeic acid in rats and which was applied to the pharmacokinetic study of caffeic acid. METHODS: The concentrations of caffeic acid in rats were determined after intragastric (ig) administration or intravenous (iv) administration of 50 mg?kg-1 caffeic acid and the pharmacokinetic parameters of caffeic acid analyzed by Topfit 2.0. RESULTS: The main pharmacokinetic parameters of caffeic acid after ig administration of caffeic acid were as follows: Cmax: (0.56?0.12) ?g?mL-1; tmax: (0.18?0.04) h; t1/2: (0.67?0.12) h; ke: (1.05?0.20) h-1; AUC(0～t): (0.34?0.05) ?g?h?mL-1. The main pharmacokinetic parameters of caffeic acid via iv administration were as follows: t1/2: (0.45?0.05) h; ke: (1.55?0.18) h-1; AUC(0～t): (9.07?2.24) ?g?h?mL-1. CONCLUSION: Administered intragastrically, caffeic acid was characterized by rapid absorption, short elimination half life (t1/2) and low absolute bioavailability in rats.