Abstract
Current approaches in developing porous 3D scaffolds face various challenges, such as failure of mimicking extracellular matrix’s (ECM) native building blocks and its functionality. Biopolymer based aerogels have shown to provide structural similarities to the ECM owing to their 3D format and a highly porous structure with interconnected pores. Utilising functional biopolymers (such as hydrophilic polysaccharides and proteins) to fabricate aerogels through freeze-drying technique is found to improve swelling degree, support cell growth and offer rapid enzymatic biodegradation, making such biomaterials appropriate as 3D scaffolds in tissue regeneration. Utilising hydrophilic natural biopolymers is associated with drawbacks such as poor mechanical properties and fast dissolvability. The present research focuses on using cellulose nanofibers (CNF) as a suspension to support the development of porous 3D aerogel biocomposites, compensating the drawbacks associated with natural biopolymers. To develop the biocomposites, CNF is blended with gelatine and starch to obtain aerogels with optimal physicochemical, mechanical and biological characteristics intended to be used as 3D scaffolds for tissue regeneration. The CNF biocomposites with various ratios of CNF: starch (CNF-starch) and CNF: gelatine (CNF-GEL)) were synthesized, and their properties were investigated in terms of physicochemical, mechanical and biological characteristics. Furthermore, Epichlorohydrin (EPH) was used to investigate the effect of chemical crosslinking on the molecular interaction of CNF-starch and CNF-GEL. Ultimately, chemical crosslinking helped to improve the mechanical resilience of the aerogels. The tunability of the physiochemical, mechanical and biological properties of the developed biocomposites makes such structure a great candidate as scaffolds for tissue engineering applications. Both in-vitro and in-vivo studies revealed satisfactory biocompatibility for the crosslinked CNF-GEL biocomposites using dermal fibroblasts. Furthermore, curcumin, a natural material with inherent antimicrobial properties, was added into the CNF-GEL biocomposite as an active molecule agent to improve the antimicrobial and anti-inflammatory responses of the scaffolds. The addition of curcumin was effective against both gram-positive and gram-negative due to the lack of existing antimicrobial characteristics in both CNF and gelatine.