Enhancement of functional properties by blending cocoon extracted Antheraea mylitta silk fibroin with polyvinyl alcohol for applications in biomedical field

Abstract

In this study, regenerated Antheraea mylitta silk fibroin (ASF) and polyvinyl alcohol (PVA) dissolved in formic acid were blended together in variable ratios to prepare blend films. The blend films presented homogeneous morphology with no visible phase separation as observed in scanning electron microscope (SEM). The structural analysis of blend films through fourier transform infrared spectroscopy and X-ray diffraction indicated the formation of co-crystals due to interaction of fibroin with PVA molecular chains. The thermal properties assessed using thermogravimetric analyzer and differential scanning calorimeter supported the molecular interactions with altered thermal stability of blend films. Incorporation of PVA into ASF enhanced the mechanical properties of blend films. The water uptake capacity, biocompatibility and biodegradability were analyzed. The L929 fibroblast skin cells seeded on blend films were found to have attached the film surface and started attaining their conventional morphology after 48 h, as observed under SEM. Alamar blue assay confirmed the cytocompatibility of blend films with more than 95% cells being viable. Based on the aforementioned encouraging results, we can assert the utility of these blend films in biomedical field for tissue regeneration applications.