Premium
Individual SERS substrate with core–satellite structure decorated in shrinkable hydrogel template for pesticide detection
Author(s) -
Wu Yiping,
Li Pan,
Yang Liangbao,
Liu Jinhuai
Publication year - 2014
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/jrs.4429
Subject(s) - dispersity , nanoparticle , materials science , substrate (aquarium) , raman scattering , composite number , nanotechnology , raman spectroscopy , surface plasmon resonance , plasmon , polymer , porosity , chemical engineering , aqueous solution , optoelectronics , composite material , polymer chemistry , chemistry , optics , organic chemistry , oceanography , physics , engineering , geology
Individual Au@PNIPAM/Ag composite has been designed and fabricated as surface‐enhanced Raman scattering (SERS) substrate in this paper. Because of the high porosity of the polymer shell and the driving force of the Au core to Ag + (H 2 O) n ( n = 1–4) in aqueous solution, chemical reactions can be carried out while aggregation is completely avoided. Also, this makes the formation of vast and monodisperse Ag nanoparticles within PNIPAM and increases the colloidal stability. The Au cores with different sizes and the vast Ag nanoparticles then form core–satellite structures that can generate plasmon resonance. Moreover, this kind of individual Au@PNIPAM/Ag composite can be seen directly through Raman optical microscope, and uncertain effects on SERS signals resulting from variability of the configurations are minimized because these individual composite particles are relatively uniform. Importantly, the gaps between the Au and Ag nanoparticles can decrease because the PNIPAM shrinks from swollen to collapse state, so the substrate can also be used for inspecting pesticide residues accurately and rapidly. Copyright © 2014 John Wiley & Sons, Ltd.