(478d) Molecular Dynamics Imaging in Micropatterned Living Cells

In the most common approach for cell micropatterning--microcontact printing of self-assembling monolayers--an elastomeric stamp of poly(dimethyl siloxane) (PDMS) is used to pattern islands of methyl-terminated alkyl thiols on gold. Remaining regions of the gold substrate are covered by a SAM of oligo(ethylene glycols) (EG SAM) that is resistant to cellular adsorption. Cells adhere to the patterned islands and assume their shapes. This and related approaches have been used to investigate the relationship between cell shape, extracellular matrix, growth and directional motility. A major drawback of microcontact printing, however, has been its unsuitability for fluorescence imaging of molecular dynamics in living cells and for correlative electron microscopy. This is because the adhesive islands on which the cells reside are supported by a layer of gold, which attenuates the fluorescence signal and scatter electrons. In this talk, we will demonstrate how this limitation can be overcome by patterning cells on substrates with transparent adhesive islands (that is, bare glass) surrounded by gold derivatized with an anti-adhesive EG SAM. Such substrates are fabricated by Anisotropic Solid Microstructuring (ASOMIC) that uses reaction-diffusion processes to chemically remove gold from an initially uniform layer into a micropatterned hydrogel stamp. We demonstrate that ASOMIC allows fluorescent imaging of living, geometrically defined cells as well as total internal reflection fluorescence (TIRF) and electron microscopy.