The ability to generate cell patter

The ability to generate cell patterns on polymer surfaces is critical for the detailed study of cellular
biology, the fabrication of cell-based biosensors, cell separation techniques and for tissue engineering. In
this study contact tape masking and steel shadow masks were used to exclude plasma immersion ion
implantation (PIII) treatment from defined areas of polytetrafluoroethylene (PTFE) surfaces. This process
enabled patterned covalent binding of the cell adhesive protein, tropoelastin, without employing
chemical linking molecules. Tropoelastin coating rendered the untreated regions cell adhesive and the
PIII-treated area non-adhesive, allowing very fine patterning of cell adhesion to PTFE surfaces. A blocking
step, such as with BSA or PEG, was not required to prevent cell binding to the underlying PIII-treated
regions as tropoelastin coating alone performed this blocking function. Although tropoelastin coated
the entire PTFE surface, the cell binding C-terminus of tropoelastin was markedly less solvent exposed on
the PIII-treated, hydrophilic regions. The differential exposure of the C-terminus correlated with the
patterned distribution of tropoelastin-mediated cell adhesion. This new methodology specifically
enables directed cell behavior on a polymer surface using a simple one-step treatment process, by
modulating the adhesive activity of a single extracellular matrix protein.