Abstract: Many studies had proved that oral administration of paclitaxel was poorly absorbed and easy to cause hypersensitivity reactions. For this reason, we produced a new nano-paclitaxel by paclitaxel granule wrapped with mannitol and Human Serum Albumin (HSA), which had better water solubility and lower systemic toxicity. In order to research the absorption of nano-paclitaxel after oral administration, the transepithelial flux of nano-paclitaxel was studied using the human colonic cell line Caco-2 cells. The flux of nano-paclitaxel (at a concentration range of 0.5-20 μmol·L^-1) across the Caco-2 cell layer was linear with time for up to 3 h. The apparent permeability coefficient (P_app) for the apical to basolateral transport of nano-paclitaxel (20.9±2.1×10^-6 cm·s^-1; N=3) and the apparent maximal concentration (K_M) of the active efflux component (14.00 μmol·L^-1) were relatively high, suggesting that nano-paclitaxel may have a better absorption rate in the intestinal tract.

Key words: nano-paclitaxel, Caco-2 cell, transport absorption, P-glycoprotein