Cytotoxicity and antibacterial properties of nano fibrous scaffolds based on extracted keratin from human hair waste and silver nano particles

As cytotoxicity and antibacterial properties are considered as two essential factors for advanced wound care dressings, many attempts have been made to introduce and apply potent substances to provide these requirements. In this study, keratin as a valuable substance extracted of human hair waste and fabricated to a nanofibrous scaffold for achieving to least cytotoxic and improved antibacterial properties. Keratin was extracted of human hair waste by an alkaline method and it was characterized by SDS-PAGE electrophoresis method. Extracted keratin was accompanied in different concentrations with PVA and silver nanoparticles and then fabricated into nano-fibrous scaffold through electrospinning method. Fabricated scaffolds were investigated and compared by scanning electron microscopy, measuring antibacterial activity (AATCC Test method 100-2004) and MTT assay (directly and by ISO 10993-5 standard method). Keratin with molecular masses of 56—65 kDa observed in the extracted substance. 3D scaffolds of nanofibers with diameter between 90-180 nm fabricated with different concentrations of kertain successfully. With the increase in keratin concentrations in fabricated scaffolds, their antibacterial activity against both Escherichia coli (ATCC8793) and Staphylococcus aureus (ATCC6538) bacteria were improved significantly. Furthermore, incorporating of keratin caused improved cell viability about 21% more in compare with the control sample. Valuable keratin was obtained from an economical source with an alkaline method. Beside the intrinsic and proven properties of keratin such as compatibility with human skin, introducing this substance to nanofibrous scaffolds caused improved antibacterial properties and cell viability making it as a potent candidate for advanced wound caring purposes.