Cell colonization of scaffolds for tissue engineering enhanced by means of plasma processes

Abstract

Synthetic biodegradable polymers are commonly used as scaffolds for tissue engineering despite their poor cell adhesion compared to natural polymers. One of the problems in using biodegradable scaffolds is that a higher cell colonization at the scaffold periphery and inadequate colonization at its center is generally noted. Such aspects could seriously compromise the in vivo regeneration of a damaged tissue and, in turn, the success of the implant. Plasma processes have been lately proven as promising scaffold modification techniques. The current work aims at enhancing cell colonization in the core of polymer scaffolds via plasma deposition of coatings with different chemical characteristics. The versatility and ability of plasma processes to modify only the outermost layer of a material can render them competitive with respect to wet chemistry approaches in the field of biomedical materials. In this paper some of the results obtained by plasma processing of 3D interconnected porous polymer scaffolds for Tissue Engineering will be shown. In particular, it will be shown how it is possible to enhance cell adhesion, growth and colonization in porous Polycaprolactone (PCL) scaffolds where gradient of surface compositions are induced from the external (e.g., hydrophobic, slightly cell-repulsive) to the internal (e.g., hydrophilic, cell-adhesive) side of the scaffolds. 3D scaffolds were modified with several RF (13.56 MHz) deposition and treatment plasma processes. Materials were characterized by means of XPS, and FT-IR techniques. Cell-growth experiments were run with cell-lines to check the efficiency of several treatments to enhance/accelerate cell in-growth inside scaffolds.