Fabrication of arbitrary polymer patterns for cell study by two-photon polymerization process

Topographically patterned surfaces are known to be powerful tools for influencing cellular functions. Here we demonstrate a method for fabricating high aspect ratio (∼10) patterns of varying height by using twophoton polymerization process to study contact guidance of cells. Ridge patterns of various heights and widths were fabricated through single laser scanning steps by low numerical aperture optics, hence at much higher processing throughput. Fibroblast cells were seeded on parallel line patterns of different height (∼1.5-lm, ∼0.8-lm, and ∼0.5-lm) and orthogonal mesh patterns (∼8-lm and ∼4-lm height, ∼5-lm and ∼5.5-lm height, ∼5-lmand ∼6-lm height). Cells experienced different strength of contact guidance depending on the ridge height. Our results demonstrate that a height threshold of nearly 1 lm influences cell alignment on both parallel line and orthogonal mesh patterns. This fabrication technique may find wide application in the design of single cell traps for controlling cell behavior in microdevices and investigating signal transduction as influenced by surface topology.