Radiation synthesis of Chitosan - polyacrylic acid nanogel integrated berberine for accelerated wound healing application: In-vitro and in-vivo evaluations

The present study explores the potential of chitosan/poly (acrylic acid) (Cs/PAA) nanogels, loaded with berberine (BBR), as an anti-inflammatory agent to enhance bioavailability and promote wound healing. Cs/PAA nanogels were synthesized through gamma radiation, which facilitated the graft polymerization of acrylic acid onto chitosan in an aqueous solution. The effect of gamma irradiation dose on the nanogel yield, average hydrodynamic diameter, and zeta potential was systematically investigated. The resultant nanogels were extracted from the opalescent solution via spray drying. Fourier-transform infrared spectroscopy (FT-IR) confirmed the successful grafting of polyacrylic acid onto chitosan and the effective encapsulation of BBR within the nanogel. Drug loading was determined to be 92%, demonstrating the efficiency of the preparation method, while the maximum drug release of 62% was observed over 300 minutes. The BBR-loaded nanogels were further evaluated for their anti-inflammatory and cytotoxic effects. In an in vivo wound healing model using adult Wistar albino rats, the BBR-loaded nanogel formulation significantly accelerated the healing of full-thickness skin wounds, reducing the wound area and promoting faster tissue regeneration.