Abstract: Objective： To investigate the oral absorption effect of liposomes with different sizes on TFu in mice. Methods： Based on former studies, TFu liposomes of different particle sizes (530nm, 320nm and 180nm) were prepared using the film dispersion-homogenization technique. The Zeta potentials and the polydispersity were evaluated by laser scatter analysis. The entrapment efficiencies were determined and the release characteristics in vitro were investigated. The mice were orally administered suspensions of TFu and liposomes of different particle sizes and venous blood was collected from the eyeholes of mice at a regular time. The plasma concentration of TFu was measured using the HPLC method and the pharmacokinetic parameters were calculated by the DAS(2.0) program. Results： The relative bioavailabilities of TFu liposomes with different particle sizes (530nm, 320nm and 180nm) were 160.5%, 221.6%, and 260.3%, respectively. Conclusion： The particle size of liposomes has a significant influence on oral absorption of TFu in mice: the relative bioavailability of liposomes increases with a decrease of particle size.

Key words: TFu, Liposomes, Paticle size, Bioavailability