Modulating biodegradation and biocompatibility of in situ crosslinked hydrogel by the integration of alginate into N,O-carboxylmethyl chitosan – aldehyde hyaluronic acid network

This study aims to investigate the mutual effect of integrating alginate (Alg) into N,O-carboxymethyl chitosan (NOCC) – aldehyde hyaluronic acid (AHA) network regarding degradation behavior and biocompatibility of the hybrid hydrogel. The introduction of Alg not only generated the synergistic effect between electrostatic interaction and Schiff-base crosslinking, which was proved to significantly enhance the system stability and prolong degradation time, but also circumvented the limitation of bio-inert property of Alg-based composites. This approach is versatile and does not required extra effort to modify chemical compositions of the hydrogel components. Fourier Transform Infrared Spectroscopy (FT-IR) analysis was used to study the crosslinking mechanism of obtained fast gelling hybrid. The variation of volume ratios between three constituent components was found to modulate the gel-forming ability, biodegradation and biocompatibility of acquired hydrogel networks. Among investigated formulations, 6:4(1:1) NOCC-Alg-AHA sample possessed desired interconnected porous structure as shown by SEM technique, appropriate water uptake capacity, extended degradation time and excellent cell attachment and proliferation through in vitro studies, which is a promising injectable scaffold and/or encapsulating substrate for tissue engineering applications. [Display omitted] •Prolong degradation rate of NOCC - AHA hydrogel without chemical modification by adding Alg.•Investigate the effect of hybrid crosslink at different volume ratio of NOCC, AHA and Alg.•Resolve the bio-inert of Alg to enhance cell adhesion and proliferation by endogenous interactions within the system.•Be used as an in-situ base to load inorganic phases, cells or drugs for further application in tissue engineering.