Electrospun polyurethane/keratin/AgNP biocomposite mats for biocompatible and antibacterial wound dressings

Keratin based biomaterials have emerged as potential candidates for various biomedical and biotechnological applications due to their intrinsic biocompatibility, biodegradability, mechanical durability, and natural abundance. The objective of this study is to combine the merits of polyurethane, keratin, and silver nanoparticles (AgNPs) together and develop a novel nanofibrous mat for wound dressing. Herein, keratin was first extracted from human hair and chemically modified with iodoacetic acid to afford S-(carboxymethyl) keratin. The modified keratin was examined using Raman spectroscopy, infrared spectroscopy, and SDS-PAGE. The keratin was then blended with polyurethane (PU) and electrospun. Subsequently, AgNPs were formed in situ to afford antibacterial PU/keratin/AgNP mats. These mats were characterized using field emission scanning electron microscopy (FE-SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), water contact angle measurements, and X-ray photoelectron spectroscopy (XPS). MTT results indicated that the introduction of keratin could accelerate fibroblast cell proliferation, while the loaded AgNPs did not weaken cytocompatibility. Antibacterial test results showed that PU/keratin/AgNP mats exerted good antibacterial property. The results from a wound healing test and a histological examination suggested that these biocomposite mats could remarkably accelerate wound recovery as compared to the conventional gauze sponge dressing. Given their excellent biocompatibility, antibacterial properties, and very mild inflammatory responses, PU/keratin/AgNP mats have great potential for wound dressing applications.