Investigating the suitability of electrohydrodynamic lithography for the fabrication of cell substrates

We have investigated the feasibility of using electrohydrodynamic lithography (EHDL) to produce large lateral areas of patterned polymer substrates for use in biomedical applications. Half centimetered squared regions of uninterrupted patterning were obtained and characterised by profilometry and microscopy. The patterning was found to be elliptical in shape and was composed of concentric bands of distinct patterns centred on initial, randomly located nucleation sites. The size of the patterned area was limited by the degree to which the inter-electrode gap could be kept perfectly parallel, with a difference in height of just 15 nm influencing the patterning. Such sensitivity meant that issues such as the stiffness of the electrodes were important. Hierarchical patterning was achieved by combining EHDL with fracture-induced structuring. The substrates fabricated using EHDL were demonstrated to be viable for cell culture in vitro using fibroblast (3T3) and muscle (C2C12) cell lines.