6-Maleimidohexanoic acid-grafted chitosan: A new generation mucoadhesive polymer.

This study aims to synthesize and evaluate a new generation mucoadhesive polymer, 6-maleimidohexanoic acid-grafted chitosan; MHA-CS, for transmucosal drug delivery compared with a well-known mucoadhesive polymer, Cys-CS. The successful synthesis was confirmed by nuclear magnetic resonance (NMR) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. Gel permeation chromatography (GPC) was used to determine the molecular weight of the synthesized polymer. The quantity of maleimide on the polymer chain as well as the mucoadhesive properties and biocompatibility of the synthesized polymers were also assessed. The results revealed that the synthesized MHA-CS demonstrated excellent mucoadhesive properties which is superior to CS and Cys-CS. The maleimide content bound to synthesized polymer was 466 μmol per gram of the polymer. The cytotoxicity test assured the low toxicity of the synthesized polymer on the normal human gingival fibroblast cells. These data support the potential of MHA-CS as a novel material for developing mucoadhesive drug delivery system with enhanced mucoadhesive properties.