title: Magnetic field induced aggregation of nanoparticles for sensitive molecular detection.
abstract: A molecular detection method utilizing the magnetically induced aggregation of silver nanoparticle (NP)-embedded silica NPs for SERS activation is described. Here, silver embedded magnetic NPs (Ag-M-dots) composed of a magnetic core and silica shells, on whose surface silver NPs were formed, were used. Because the magnetic field induced aggregated Ag-M-dots exhibit a strong SERS signal compared to the dispersed Ag-M-dots, the system allows for the detection of adsorbed Raman label compound even at the 100 fM level. Adenine was tested as a model biocompound and its Raman spectrum could be observed at concentrations as low as 1 pM. The experimental results were supported by the theoretical calculations.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul, 151-747, Korea.
authors.forename: Bong-Hyun
authors.initials: BH
authors.lastname: Jun
authors.forename: Gunsung
authors.initials: G
authors.lastname: Kim
authors.forename: Jongho
authors.initials: J
authors.lastname: Baek
authors.forename: Homan
authors.initials: H
authors.lastname: Kang
authors.forename: Taeho
authors.initials: T
authors.lastname: Kim
authors.forename: Taeghwan
authors.initials: T
authors.lastname: Hyeon
authors.forename: Dae Hong
authors.initials: DH
authors.lastname: Jeong
authors.forename: Yoon-Sik
authors.initials: YS
authors.lastname: Lee