Tuneable Thiol-Ene Photo-Crosslinked Chitosan-Based Hydrogels for Biomedical Applications

Access to biocompatible hydrogels with tuneable properties is of great interest. Here we report the practical synthesis and characterisation of a series of photo-crosslinked chitosan hydrogels from norbornene-functionalised chitosan (CS-nb) and various thiolated crosslinkers. The resulting materials were characterised by NMR, swelling ratio, rheology, SEM and SANS. The new hydrogels exhibit pH- and salt-dependent swelling whilst the macro- and microscale properties can be modulated by the choice and degree of crosslinker or the polymer concentration. The materials can be molded in situ and loaded with small molecules that are released overtime. Moreover, the incorporation of collagen in the hydrogels drastically improves cell adhesion and excellent cell viabilities were observed with human dermofibroblast cells for up to 6 days, highlighting the potential use of these materials in the biomedical area.