Graphene integrated Nanocellulose - Sodium alginate hydrogel for burn wound healing applications

Growing research attention has been directed towards developing innovative and sustainable biomaterials for effective wound care. Hydrogels based on biopolymers offer great promise as a substitute for conventional wound dressing materials. Its three-dimensional hydrophilic crosslinked structure has unique wound healing properties, since it maintains a moist microenvironment in the affected area. In this work, a novel hydrogel is fabricated based on nanocellulose and sodium alginate with varying concentrations of graphene quantum dots (GQDs). The cellulose nanofibers were prepared from the rice straw, an abundant agricultural waste material and a sustainable, eco-friendly source. The amino acid L-cysteine was used as the precursor for the synthesis of GQDs. The structural and physicochemical properties of the hydrogels were characterised through analytical techniques. The fibrous nature of cellulose nanofibers and elliptical shape of GQDs were demonstrated in Transmission Electron Microscopy (TEM). The effective formation of the hydrogel network was confirmed by Fourier Transform Infrared Spectroscopy (FTIR). Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), revealed porous morphology and surface roughness of the hydrogels. Thermogravimetric analysis (TGA) has shown a thermal stability up to 220˚C of the hydrogels at the optimal concentration of GQDs. The cell viability studies conducted using fibroblast cell lines (L929) illustrated the biocompatibility of the hydrogels. The samples exhibited remarkable anti-microbial and anti-inflammatory activities with varying concentration of GQDs. In vitro scratch wound assays further confirmed the efficiency of hydrogels in the wound closure. The results highlight the strong potential of the synthesized hydrogels for burn wound care.