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

Guanghua Liu, Jianqun Gan, Aimin Chen, Qian Liu, Xusheng Zhao

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DOI: 10.4236/ns.2010.27087                

Abstract

An amphiphilic N-octyl-O-methoxy poly (ethylene glycol) chitosan was successfully prepared by grafting successively octyl groups onto amino groups at chitosan’s C-2 position as hydrophobic moieties and methoxy polyethylene glycol (MPEG) groups onto hydroxyl groups at C-6, C-3 as hy-drophilic ones. A certain amount of -NH2 was retained in the structure of chitosan derivatives through protection by phthalic anhydride. The chemical structures and degree of N-and O-substitution of chitosan derivatives were characterized by FTIR, 1H NMR, GPC and elemental analysis, respectively. The amphiphilic property for convenient self-assembly and the preserved -NH2 groups for progressive chemical cross-linking make the resultant Nocyl-O-MPEG chitosan soluble in water and potentially applicable in preparing stable chitosan hollow microspheres, a demanding drug-carrier in medical and pharmaceutical sciences.

Keywords

Amphiphilic Groups; Chitosan Derivatives; Protection; Hollow Microsperes

Conflicts of Interest

The authors declare no conflicts of interest.

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