title: Magnetic manipulation and optical imaging of an active plasmonic single-particle Fe-Au nanorod.
abstract: Superparamagnetic microbeads play an important role in a number of scientific and biotechnology applications including single-molecule force measurements, affinity separation, and in vivo and in vitro diagnostics. Magneto-optically active nanorods composed of single-crystalline Au and polycrystalline Fe segments were synthesized with diameters of 60 or 295 nm using templated electrodeposition. The Fe section was magnetically soft and had a saturation magnetization of approximately 200 emu/g, resulting in a 10-fold increase in magnetization relative to that iron oxide nanoparticles. The strong plasmonic response of the Au segment of the rod in both the longitudinal and transverse directions made it possible to detect the orientation of a single rod in a polarized light microscope with nanometer resolution. These nanorods provide significantly improved physical properties over iron oxide superparamagnetic beads, making it possible to simultaneously manipulate and monitor the orientation of biomolecules with well-defined forces at the nanometer scale.
authors: School of Chemistry and Chemical Biology, University College Dublin, Dublin 4, Ireland.
authors: Yong
authors: Y
authors: Zhang
authors: Manuel
authors: M
authors: DaSilva
authors: Brian
authors: B
authors: Ashall
authors: Gillian
authors: G
authors: Doyle
authors: Dominic
authors: D
authors: Zerulla
authors: Timothy D
authors: TD
authors: Sands
authors: Gil U
authors: GU
authors: Lee
mesh_terms: D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007501:Iron / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008280:Magnetics / Q000379:methods*; D060306:Magnetometry; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008854:Microscopy, Electron; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size
chemical_list: D006046:Gold; D007501:Iron