Construction of cellulose/carboxymethyl chitosan hydrogels for potential wound dressing application

In this study, novel cellulose/carboxymethyl chitosan (CMCS) composite hydrogels were prepared by blending cellulose and CMCS in LiOH/urea aqueous solutions, and then cross-linking with epichlorohydrin. The structure and morphology of the composite hydrogels were characterized by Fourier transform infrared spectroscopy, wide-angle x-ray diffraction, thermo-gravimetric analysis, and scanning electron microscopy. The results revealed that chemical cross-linking reaction between cellulose and CMCS occurred in the hydrogel. Moreover, CMCS contributed to the enhancement of pore size, whereas cellulose acted as a strong backbone in the hydrogel to support the pore wall. The compressive strength of the composite hydrogels was significantly improved from 39.2 ± 2.2 to 145.2 ± 2.8 kPa as a result of the increase in cellulose content, while the equilibrium swelling ratio increased rapidly from 33.8 to 154.2 g/g with the increase in CMCS content. The composite hydrogels showed no cytotoxicity towards L929 cells, suggesting good biocompatibility. All these results indicate that the proposed cellulose/CMCS composite hydrogels can be effectively used as wound dressing materials.