Facilely preparing carboxymethyl chitosan/hydroxyethyl cellulose hydrogel films for protective and sustained release of fibroblast growth factor 2 to accelerate dermal tissue repair

Fibroblast growth factor 2 (FGF-2), a cytokine that plays a crucial role in wound healing, has not been thoroughly applied in clinical wound treatment due to its instability and short half-life. Here, carboxymethyl chitosan (CMCS)/hydroxyethyl cellulose (HEC) hydrogel films prepared by blending and casting method were used for delivery and controlled release of FGF-2 to improve its bioavailability in animal burn treatment. The CMCS/HEC (at 4:1 wt ratio) hydrogel films exhibited a porous structure, 20- to 30-fold swelling degrees, stimulation of NIH/3T3 cell proliferation, protective mode of FGF-2 from protease, and a sustained FGF-2 release rate of over 50% in aqueous solutions with preserved biological activity. In burned murine skinregeneration, FGF-2-incorporated hydrogel films significantly stimulated early re-epithelialization, early granulation tissue formation, angiogenesis, attenuated hypertrophic scar, and induced the expression of vascular endothelial growth factor A and matrix metalloproteinase 9 in repairing skin tissues. Collectively, FGF-2-incorporated CMCS/HEC hydrogel film could potentially become a novel wound dressing for burn treatment.