To improve therapeutic responses besides tumors, various drugdelivery systems have been developed. Recently, the core-shell structure of polymeric micelles or nanoparticles consisting of hydrophilic and hydrophobic groups has been proposed as a drug delivery system. In the aqueous phase, their hydrophobic cores are surrounded by hydrophilic covering, because a hydrophobic core can occur an intermolecular association within micelles or nanoparticles. So micelles or nanoparticles may serve to enhance the water-soluble, long circulation time, bio-compatible properties, and container for the drug.