Surface properties of and cell adhesion onto allylamine-plasma-coated polyethylenterephtalat membranes.

Allylamine was plasma polymerised onto a polyester (PET) membrane to obtain a surface with good cell adhesive properties. Samples were coated using a microwave plasma source operating at different process parameters. The effect of process parameters on the physical, and chemical properties of plasma-polymerised-allylamine (PPAa) was evaluated by studying elemental composition, amine concentration, wettability, and surface morphology. A relatively high amine concentration was measured (up to 50 nmol/cm2). In parallel, nitrogen enrichment was observed after exposure to high-energetic plasma. Irrespective of the treatment conditions, oxygen was incorporated into the polymer structure. PPAa surfaces were found to be more hydrophilic than PET. The wettability of the samples increased with increasing amine concentration. Pictures from scanning electron microscopy indicated that homogeneous pinhole-free PPAa layers were deposited on PET membranes, without a significant change of permeability. In vitro evaluation of biocompatibility was carried out by studying human skin fibroblast interaction with surfaces. Cell attachment and viability on PPAa layers were found to be more intensive than on the control PET, based on the higher metabolic activity of adhering cells, but also on morphological criteria including overall cell morphology.