Synthesis and Characterization of Novel Amphiphilic Chitosan Derivatives and Its Solubilizing Abilities for Water-insoluble Drugs

Novel chitosan derivative with long alky groups as the hydrophobic moieties and carboxymethyl groups as the hydrophilic moieties was synthesized. The chemical structure of N-octyl-O,N-carboxymethyl chitosan(OCC) was characterized via FTIR, 1H NMR and elemental analysis. The physical properties were analyzed with wide angle X-ray diffraction(WAXD) and differential scanning calorimetry(DSC). The solubilities in some solvents were investigated and solubilization abilities of OCC for water-insoluble drugs were evaluated. The results show that the degree of substitution of carboxymethyl groups and octyl groups are determined to be 115.9% and 58.0%, respectively. OCC are insoluble in organic solvents while show a much better solubility in water and formed opalescence solutions, which increased the solubility of paclitaxel up to 500 folds in water. The drug loading and drug encapsulation efficiency of OCC are 34.6% and 89.9%, respectively. It was concluded that the present OCC could be potentially useful as the novel delivery carrier materials for insoluble drugs.