CELL-ADHESION TO PLASMA-TREATED POLYMER SURFACES

Polymer surfaces were modified by glow discharge to study the effect of surface treatment on cell adhesion using polyethylene, polytetrafluoroethylene, poly(ethylene terephthalate), polystyrene, and polypropylene films. The surface wettability of all the films, evaluated by the water contact angle, decreased with respect to the length of plasma treatment. For each of the polymers, a different dependence of cell adhesion on the length of plasma treatment was observed, but, in each case, the optimal water contact angle for cell adhesion was approximately 70-degrees. The X-ray photoelectron spectroscopy (XPS) of the plasma-treated surfaces using a derivatization method suggested that hydroxyl groups were primarily introduced onto the surfaces of the polymer by plasma treatment. Formation of carboxyl groups by plasma treatment was also observed from XPS, although streaming potential measurements could not identify the newly generated groups.