Preparation and characterization of oxidized konjac glucomannan/carboxymethyl chitosan/graphene oxide hydrogel.

Polysaccharide hydrogels have been widely used as biomaterials in biomedical field. In this article, composite hydrogels were prepared through the Schiff-base reaction between the aldehyde of oxidized konjac glucomannan (OKGM) and the amino of carboxymethyl chitosan (CMCS). Meanwhile, different amount of graphene oxide (GO) was added as nano-additive. The hydrogels have been characterized by various methods including Fourier transform infrared spectroscopy (FT-IR) and Surface morphology (SEM). Through the observation of SEM, the hydrogels' scaffolds present a homogeneous interconnected pore structure after lyophilizing. In addition, the influence of different GO content on properties including gelation time, swelling ability, water evaporation rate and mechanical properties was investigated. The results indicate that the hydrogels have short gelation time, appropriate swelling ability and water evaporation rate. Especially, the compressive strength and modulus increase 144% and 296% respectively as the GO content increase from 0 to 5mg/ml. Moreover, MTT assay was applied to evaluate the biocompatibility of hydrogels. The result indicate that hydrogels with GO show better biocompatibility. Therefore, due to the appropriate water absorption capacity, the similar compressive modulus with soft tissue and excellent biocompatibility, the composite hydrogels have potential application in wound dressings.