Nanocellulose mediated injectable bio-nanocomposite hydrogel scaffold-microstructure and rheological properties

Here we report, for the first time, development of nanocellulose based novel bio-nanocomposite injectable hydrogel scaffold. An integrated approach has been used to incorporate ultrafine fluorcanasite (FC) glass-ceramic particulates within nanocellulose matrix, synthesized from lignocellulosic biomass. Epichlorohydrin (ECH) was used as a chemical cross-linking agent for hydrogel synthesis. The compositions and properties of bio-nanocomposite hydrogels were controlled by varying the loading of FC and ECH. Moreover, microstructural characterizations and functional group analysis of synthesized nanocellulose and bio-nanocomposite hydrogels were carried out using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). SEM studies revealed successful extraction of cellulosic nanofibres and interconnected porous micro-architecture of injectable hydrogels. Incorporation of FC particulates resulted into development of well-defined micro-porous morphology. FT-IR studies indicated the presence of hydroxyl groups and possible interactions between nanocellulose and FC reinforcements. The rheological study of the developed injectable hydrogel was carried out at different frequency, amplitude and temperature sweeps. The studies revealed that after the incorporation of FC, dynamic storage modulus increased, while synergistically enhancing the injectability of the bio-nanocomposite hydrogels. An optimum loading level of FC reinforcement could also be established. Swelling behaviour studies of the hydrogels demonstrated higher degree of swelling and enhanced structural integrity with incorporation of FC. The novel bio-nanocomposite injectable hydrogels developed in this study, could demonstrate promising potential as injectable implant material.