Surface-Enhanced Raman Spectroscopy on Selectively Adsorbed Plasmonic Nanostructures Using Polar Surface Arrays

This paper introduces an approach that enables highlyadjustablesurface adsorption of single plasmonic nanostructures using polarsurface arrays. The plasmonic nanostructures are made from DNA origamiand functionalized with gold nanoparticles for surface-enhanced spectroscopictechniques. To ensure that the contribution of individual nanostructuresto the measured signal can be detected without any interference fromthe surrounding structures, we aimed to control the distance and seta minimum gap between the nanostructures on the substrate surface.We describe the fabrication process of the polar surface array basedon electron beam lithography, followed by functionalization. Our resultsindicate that the concentration of DNA origami structures and theduration of the incubation primarily affect the number of adsorbednanostructures. Density functional theory simulation explains theselective adsorption of plasmonic nanostructures due to the substratesurface properties. The spatial arrangement of nanostructures allowsfor the reliable identification of the Raman signal's location,while a falsified identification resulting from agglomeration is prevented.