title: Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution.
abstract: We demonstrate that scattering near-field microscopy (s-SNOM) can determine infrared "fingerprint" spectra of individual poly(methyl methacrylate) nanobeads and viruses as small as 18 nm. Amplitude and phase spectra are found surprisingly strong, even at a probed volume of only 10(-20) l, and robust in regard to particle size and substrate. This makes infrared spectroscopic s-SNOM a versatile tool for chemical and-in the case of protein-secondary-structure identification.
authors.affiliation: Max-Planck-Institut für Biochemie & Center for NanoScience (CeNS), München, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Brehm
authors.forename: Thomas
authors.initials: T
authors.lastname: Taubner
authors.forename: Rainer
authors.initials: R
authors.lastname: Hillenbrand
authors.forename: Fritz
authors.initials: F
authors.lastname: Keilmann
mesh_terms: D006046:Gold / Q000737:chemistry; D008853:Microscopy / Q000295:instrumentation* / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012542:Scattering, Radiation; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation*; D014780:Viruses / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D006046:Gold; D019904:Polymethyl Methacrylate