On Au(111)/PEG-C9t these bands appear much stronger with main peaks at 1465 cm -1 , 1630 cm -1 , 1710 cm -1 . As PEG molecules have no absorption in this region, this variation might be caused by a significant change in the orientation of the C9t chains. On Au(111)/(PEG-C9t)+ S protein broad bands appear in this region which come from an overlap of several vibrations including aptamer rings, and protein amide I and II on the surface (table ).