Synthesis and characterization of an amphiphilic chitosan bearing octyl and methoxy polyethylene

Abstract

An amphiphilic N-octyl-O-methoxy poly (ethyl-ene glycol) chitosan was successfully prepared by grafting successively octyl groups onto amino groups at chitosan's C-2 position as hy-drophobic moieties and methoxy polyethylene glycol (MPEG) groups onto hydroxyl groups at C-6, C-3 as hydrophilic ones. A certain amount of -NH 2 was retained in the structure of chitosan derivatives through protection by phthalic an-hydride. The chemical structures and degree of N-and O-substitution of chitosan derivatives were characterized by FTIR, 1 H NMR, GPC and elemental analysis, respectively. The amphiphi-lic property for convenient self-assembly and the preserved -NH 2 groups for progressive chemical cross-linking make the resultant N-ocyl-O-MPEG chitosan soluble in water and po-tentially applicable in preparing stable chitosan hollow microspheres, a demanding drug-carrier in medical and pharmaceutical sciences.