Chromophore binding to in vitro engineered bio-mimetic surfaces

In the retina, a chromophore isomerizes and the protein to which it binds changes shape. In this proof-of-concept experiment we engineer an artificial surface to mimic the physiochemical environment of the retina and the key reaction of the visual cycle. We immobilized small peptides on silicon and assessed changes in their surface properties upon chromophore binding via ellipsometry, X-ray photoelectron spectroscopy and atomic force microscopy. Our observations suggest that when binding occurs it is accompanied by changes in the properties of the film composed of surface-anchored peptides.