Surface modification of NPs allows longer blood-circulation and favors its preferential accumulation in solid tumors by EPR effect. d--Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a water-soluble derivative of natural vitamin E and polyethylene glycol (PEG) 1000. TPGS has been used as solubilizer and absorption enhancer in some drug delivery formulations. Also, TPGS inhibits P-gp-mediated multidrug resistance in tumor cells, and thus enhance drug permeation and increases the oral bioavailability of anticancer drugs [25]. It was found that TPGS could also effectively inhibit the growth of human lung carcinoma cells in vitro and in vivo