Near superhydrophobic fibrous scaffold for endothelialization: fabrication, characterization and cellular activities

In this work, we have applied an electrospinning method to control wettability and further hydrophobic modification of a hydrophobic polymer mat of poly(vinylidene fluoride-co-hexafluoropropylene). A correlation between the processing parameters, rheological properties of polymer solutions, and electrospinning ability was made using the polymer's critical entanglement concentration, the boundary between the semidilute unentangled regime and the semidilute entangled regime. The wetting behavior, structural and thermal characteristics of electrospun (ES) mats were evaluated and compared with solvent cast sample using advancing and receding contact angle analyses, differential scanning calorimetry, and small-angle X-ray scattering. To demonstrate the feasibility, the best optimized ES samples were examined for their potential and ability to support bone marrow derived endothelial cell seeding efficiency, adhesion and proliferation. Our studies show that, while different processing techniques can effectively modulate physical and morphological changes such as porosity and hydrophobicity, the cellular adhesion and proliferation are highly time-dependent and controlled by chemical factors. As such, these results suggest that it is the interplay of both physical and chemical factors that determine the endothelialization of porous near superhydrophobic scaffolds. The developed electrospun samples demonstrate their feasibility for endothelialization.