Selective neuronal cell attachment to a covalently patterned monoamine on fluorinated ethylene propylene films

The patterned covalent surface addition of a monoamine to fluorinated ethylene propylene films (FEP) controls both cellular attachment and differentiation in defined media conditions. A radio frequency glow discharge (RFGD) process was used to replace FEP surface fluorine atoms with hydroxyl groups. The primary amine was then covalently attached by polymerizing aminopropyl-triethoxysilane (APTES) via the hydroxyl functionalities. The selective attachment of cells to the APTES regions was determined to be dependent upon the initial adsorption of albumin to the patterned FEP membrane. Albumin was determined to enhance cellular attachment to the APTES regions and prevent attachment to the unmodified FEP areas for both an NB2a neuroblastoma cell line and primary rat endothelial cells. If albumin were not preadsorbed onto the membrane, selective attachment to the modified regions would not occur. Radiolabeling albumin with 125I demonstrated the preference of albumin for adsorption onto the monoamine surface where the cells preferentially attached. Both hydrophobic and ionic forces contributed to the adsorption process. Although selective cellular attachment to the patterned APTES regions could be achieved by albumin preadsorption to the surface, the neuroblastoma cells did not significantly differentiate unless additional serum components were supplemented to the media.