Mechanically Robust Poly(vinyl alcohol)-Egg White Composite Hydrogel with Enhancing Biocompatibility by Unidirectional Nanopore Dehydration

A simple and green method, unidirectional nanopore dehydration (UND), directly processes 10% poly(vinyl alcohol) (PVA) aqueous solution containing 20% egg white (EW) into a composite hydrogel membrane (PVA-EW). The tensile strength and elongation of the UND-based PVA-EW at 25 degrees C were 0.91 MPa and 534.17%, respectively, while the two values at 70 degrees C were increased by 700 and 38%, respectively. The PVA-EW (70 degrees C) was still dominated by random coils and alpha-helical structures. The hydroxyl groups of intramolecules and intermolecules of both PVA and EW could be able to combine and form either more hydrogen bonds or stronger hydrogen bonds. PVA-EW is soft and translucent, has good mechanical properties, and has a porous networked structure with pores that have a diameter of 1-10 mu m. L-929 mouse fibroblasts were found to be able to adhere, grow, and proliferate well on the hydrogel composite membrane. This novel PVA-EW biomaterial has potential applications in biomaterials especially medical tissue engineering.