Nanostructuration of titania films prepared by self-assembly to affect cell adhesion

Nanostructured and dense titania films prepared by evaporation-induced self-assembly (EISA) are shown to possess tunable topographical nanoscale features on the order 2-12 nm. Thermal treatment (calcination) induces a transition from amorphous titania to crystalline anatase that modifies the chemical and structural properties of the surfaces via the migration of matter. For nanostructured films, the nanoporous network changes from organized ellipsoidal pores, approximately 4 nm x 2 nm, to a grid-like structure with pores on the order of 12 nm, whereas dense films show a slight roughening of the surface. Cells seeded on templated films show measurable, statistically significant differences in morphology compared with cells seeded on dense films. Moreover, although crystallization of templated films results in surfaces that promote less well-spread cells with higher circularities, the opposite trend is observed for dense films. As such, these results represent a new method to tailor interfaces for biomaterial applications, using EISA to control material patterning on the nanoscale. This self-assembly based approach allows the patterning on size scales that are inaccessible by most traditional techniques while offering the added potential to package and control the release of bioactive molecules.