Pharmacokinetics study of a supersaturatable self-microemulsifying drug delivery system for ellagic acid by UHPLC-Q-TOF-MS

To evaluate the bioavailability of ellagic acid loaded super-saturatable self-microemulsifying drug delivery system (S-SMEDDS), its pharmacokinetic properties were studied in rats with an ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry. The plasma samples were treated by solid-phase extraction method, and gallic acid was used as the internal standard when determining the concentration of ellagic acid. Results showed that the established analytical method was sensitive and accurate, which is applicable to the pharmacokinetic study of ellagic acid. The drug was found to be absorbed rapidly in vivo, and the plasma concentration-time curve showed double peaks, indicating that ellagic acid were reabsorbed by entero-hepatic circulation after oral administration. Compared with ellagic acid suspension, the apparent clearance of ellagic acid-loaded S-SMEDDS and SMEDDS reduced significantly, and the AUC_0~t of them were 4.7 and 5.8-fold increase, respectively. Therefore, the bioavailability of ellagic acid-loaded S-SMEDDS was higher than that of the suspension and SMEDDS.