A Tri-component-based Hydrogel Wound Dressing with Antibacterial and Hemostatic Competences Based on the Naturally Occurring Macromolecules and Silver Nanoparticles

A nanocomposite hydrogel consisting of chitosan/gelatin/polyethylene glycol and silver nanoparticles was prepared for wound dressing application using gamma irradiation. The chitosan and gelatin solutions were mixed with different blending ratios in an aqueous solution of polyethylene glycol (PEG) and then silver nanoparticles were dispersed in the system using ultrasonic technique. The samples were treated at a dose of ۱۰ kGy and turned into a gel. Chemical, morphological, mechanical, swelling, antibacterial and hemostatic properties of the wound dressings were studied with a number of analyses. The results corroborated that water swelling and water vapor transmission decreased with the increase of gelatin content. The swelling ratio and vapor transmission rate of the sample with the highest amount of gelatin (C۱/G۳) decreased by ۴۷.۵% and ۳۹% comparing the sample with the highest amount of chitosan (C۳/G۱). With the inclusion of silver nanoparticles, swelling ratio increased by ۳-۵%, whereas, vapor transmission rate decreased by ۲-۸% comparing the pristine hydrogels. The gel content raised with the increase of gelatin content and incorporation of AgNPs. The gel content of C۱/G۳ increased by ۴۴% comparing C۳/G۱. And incorporation of AgNPs caused a ۰-۱۸% increase of gel content values. The tensile strength and elongation at break increased by ۴۹% and ۴۷% in C۱/G۳ comparing C۳/G۱ compositions. The nanoparticle inclusion further promoted the tensile strength and elongation at break by ۲-۱۱% and ۳-۴۲%, respectively. The blood clotting analysis proved that the blood clothing depressed in parallel with the gelatin increment. The results of antibacterial analyses corroborated that AgNPs loaded dressing possesses substantially higher bacterial inhibition zone. To sum up, chitosan/gelatin/ AgNPs nanocomposites with the acceptable level of water swelling, water vapor transmission, blood clotting and considerable antibacterial properties can be a very appealing candidate as a wound dressing.