title: A general route towards well-defined magneto- or fluorescent-plasmonic nanohybrids.
abstract: Herein, we present a general route towards defined nanohybrids, comprised of a fluorescent quantum dot (QD) or superparamagnetic iron oxide (Fe2O3) nanocrystal core and a tuneable corona of plasmonic gold or silver nanoparticles (NPs), adhered by a cross-linked poly(isoprene)-b-poly(ethylene glycol) diblock copolymer (PI-b-PEG) matrix. To this end, the PEG-terminus of the amphiphilic polymer was acylated with lipoic acid (LA), which, as is known, forms quasi-covalent Au-thiol- or Ag-thiol-bonds. Surprisingly, by variation of the ratio of the different NPs, inverse core/satellite structures bearing QDs or Fe2O3 around a metallic NP core were obtained. Furthermore, gold NPs or even closed gold shells were grown by in situ reductive deposition of Au(3+) ions on Fe2O3 NP seeds. Finally, in order to demonstrate the scope of the method, ternary nanohybrids, composed of QDs, Fe2O3 and Au NPs, were accomplished. All magneto-plasmonic and fluorescent-plasmonic materials were thoroughly characterized by absorption and emission spectroscopy, TEM and TEM-EDX. Antibody conjugation to these novel nanohybrids proved their practical utility in a prototype immunoassay.
authors.affiliation: Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany. schmidtke@chemie.uni-hamburg.de weller@chemie.uni-hamburg.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Schmidtke
authors.forename: Hauke
authors.initials: H
authors.lastname: Kloust
authors.forename: Neus G
authors.initials: NG
authors.lastname: Bastús
authors.forename: Jan-Philip
authors.initials: JP
authors.lastname: Merkl
authors.forename: Huong
authors.initials: H
authors.lastname: Tran
authors.forename: Sandra
authors.initials: S
authors.lastname: Flessau
authors.forename: Artur
authors.initials: A
authors.lastname: Feld
authors.forename: Theo
authors.initials: T
authors.lastname: Schotten
authors.forename: Horst
authors.initials: H
authors.lastname: Weller