Development of a micro-patterned membrane consisting of a PCL/Keratin/PEGDE ternary blend using PSµM for potential biotechnological applications

The incorporation of the structural fibrous scleroprotein keratin into synthetic polymers may be a solution for the development of biomaterials with advanced properties. This study aimed to develop micro-patterned membranes based on poly(ε-caprolactone)(PCL) polymer blended with native or polyethylene glycol diglycidyl ether (PEGDE) cross-linked keratin, suitable for guiding cell attachment and orientation for potential biotechnological applications. First, human hair keratin was extracted; its biochemical composition and physicochemical properties were analyzed. Then, micropatterned membrane constructs from PCL blended with 20% and 40% by mass of keratin were created using phase separation micromolding for the first time. Four different mold micropatterns were evaluated; the one applicable to all polymer compositions was determined [(channel:20μm)x(height:10μm)x(ridge:10μm)]. The constructs were extensively investigated for their physicochemical (FTIR, XRD), thermal (DSC,TGA), morphological (SEM), mechanical (compressive-tensile strength, degradation) and in vitro biological (hemocompatibility, cytocompatibility) properties. While blending PCL with keratin did not affect the physicochemical and melting temperature of PCL, it significantly affected the mechanical properties of the constructs. Compressive strength increased linearly with the addition of keratin, especially with cross-linked keratin. All constructs were found to be highly hemocompatible (<0.2% hemolysis). Stem cell interactions showed cross-linked keratin-blended PCL constructs could be suitable substrates for cell alignment and proliferation.