Fabrication of nanostructures of poly(ethylene glycol) and its application to protein adsorption and cell adhesion

We developed a method for fabricating poly(ethylene glycol) (PEG) nanostructures using capillary lithography mediated UV exposure. A PEG dimethacrylate (PEG-DMA) was used for crosslinking, which could be applied to other PEG polymers having a crosslinking group. In comparison to unstructured, planar PEG films, the hydrophobicity was significantly enhanced on PEG nanostructures presumably due to embedded air in the nanostructures, as confirmed by contact angle measurements of water. A number of proteins and cells were tested to examine the effects of the modification of surface properties on protein adsorption and cell adhesion. It was found that proteins and cells adhered on a nanostructured PEG surface slightly higher than on a bare PEG film, but much less than on glass control, which could be attributed to the increased surface area and hydrophobicity.