Polymeric amphiphiles consisting of hydrophilic and hydrophobic segments can form micelles or micelle-like self-assemblies with a hydrophobic core and a hydrophilic shell due to non-covalent association arising from intra and/or intermolecular interactions among hydrophobic segments in aqueous media.These self-assemblies have potential uses in biotechnology and medicine due to their unique supramolecular structures.Novel self-aggregated nanoparticles were prepared from polymeric amphiphiles,cholesterol-modified O-carboxymethyl chitosan (CCMC) conjugates,and the relationships between the chemical structure,the amphiphilic property and the morphological characteristics of CCMC self-aggregated nanoparticles were investigated in this study.