Cell patterning on poly(sodium 4-styrenesulfonate)-patterned fluoropolymer substrate

• PFA films were functionalized by ion-beam induced surface graft polymerization.
• Poly(sodium 4-styrenesulfonate) (PSS)-patterned PFA films were prepared.
• Well-organized cell patterns were obtained on PSS-patterned PFA films.
• This method is useful to fabricate bio-platforms for cell-based biodevices.

The surface functionalization of bio-inert fluoropolymer films through ion beam-induced surface graft polymerization was investigated to control the cellular behavior. The surface of poly(tetrafluoroethylene-co-perfluoropropl vinyl ether) (PFA) films was selectively activated by 150 keV H+ ion implantation in the presence of a pattern mask and sodium 4-styrenesulfonate (SS) was then graft polymerized onto the implanted PFA films to form hydrophilic poly(sodium 4-styrenesulfonate) (PSS)-patterned PFA films. The surface of the resulting PSS-patterned PFA films was investigated in terms of the degree of graft polymerization, chemical structure, chemical composition, wettability, and morphology. The analytical results revealed that PSS was selectively grafted onto the implanted regions of the PFA films. Furthermore, in vitro cell culture on the PSS-patterned PFA films exhibited a preferential adhesion and growth of cells onto the PSS-grafted regions, resulting in well-organized 100 μm cell patterns.