Preparation and performance study of thermo-responsive P(NIPAM-AM-ABP)/keratin composite nanofiber membrane for bio-application

This paper describes a temperature-responsive composite nanofibrous membrane by blending of the P(NIPAM-AM-ABP) (PNAA) nanofiber and the wool keratin (WK) nanofiber. The photo crosslinkable PNAA with the LCST value of 38.1 °C was obtained by free radical copolymerization of the temperature sensitive N-Isopropylacrylamide (NIPAM) monomer, the hydrophilic monomer Acrylamide (AM), and the photo crosslinkable monomer 4-Acryloyloxybenzophenone (ABP). Keratin was extracted from waste wool fiber by reduction method. The PNAA nanofiber (PNAA-NF) and the keratin nanofiber (WK-NF) were electoral spun separately by two-needle parallel spinning, and the obtained composite nanofiber membrane was then crosslinked by UV irradiation and heat treatments to prepare the PNAA/WK nanofiber membrane (PNAA/WK-NFM) with good water tolerance. The result indicated that the photo cross-linkable temperature sensitive PNAA with the LCST of 38.1 °C was successfully synthesized. The obtained PNAA/WK-NFM has a good fibrous morphology and excellent water tolerance. The composite nanofiber membrane showed good reversible temperature sensitivity and temperature responsive drug releasing property due to the PNAA. By combining of the PNAA-NF and WK-NF, the mechanical property of the PNAA/WK-NFM was greatly enhanced in both dry and wet states, and the slow drug releasing property of the membrane was further improved. In-vitro cell culture experiments indicated that the PNAA/WK-NFM has a good biocompatibility with no cytotoxicity. These findings suggested that the PNAA/WK-NFM has a potential application in temperature responsive drug releasing biomaterials.