Au@pNIPAM colloids as molecular traps for surface-enhanced, spectroscopic, ultra-sensitive analysis.

Departamento de Química-Física and Unidad Asociada CSIC-Universidade de Vigo, 36310 Vigo, Spain.
Angewandte Chemie International Edition (Impact Factor: 11.34). 12/2008; 48(1):138-43. DOI: 10.1002/anie.200804059
Source: PubMed

ABSTRACT Caught in a trap: Colloids of gold nanoparticles coated with a thermally responsive poly‐(N‐isopropylacrylamide) (pNIPAM) microgel can trap molecules in different ways as a function of temperature (see scheme). The porous pNIPAM shells prevent electromagnetic coupling between metal particles, thus providing highly reproducible surface‐enhanced Raman scattering (SERS) signals and intensity.

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May 29, 2014