title: Generation of ultralarge surface enhanced Raman spectroscopy (SERS)-active hot-spot volumes by an array of 2D nano-superlenses.
abstract: Surface Enhanced Raman Spectroscopy (or SERS) has received tremendous attention in the past three decades. However, the extremely-confined probe volume (1 nm) of the plasmonic hot-spots occurring on a conventional roughened SERS-active metallic surface has limited value in macro-molecular studies. In this article, we show the plausibility of generating large SERS hot-spot volumes on an atomically-flat metal surface based upon a special 3D adiabatic plasmonic nano-focusing effect brought about by an array of nano-scale superlenses. We experimentally demonstrate the feasibility of this particular approach and report, for the first time, the acquisition of whole-protein SERS spectra of a layer of test protein, Cytochrome-c, using a custom-made Otto-Raman spectroscopy system equipped with nano-fluidics. Our study shows the potential of whole-protein SERS spectroscopy as a useful analytical tool that complements surface probe microscopies.
authors: School of Physics, National University of Ireland, Galway, Ireland.
authors: KhoKiang
authors: K
authors: Wei
authors: ZeXiang
authors: Z
authors: Shen
authors: Olivo
authors: O
authors: Malini
mesh_terms: D045304:Cytochromes c / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D007909:Lenses; D053768:Metal Nanoparticles / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D006046:Gold; D045304:Cytochromes c