Mixed Monolayers on Gold Nanoparticle Labels for Multiplexed Surface-Enhanced Raman Scattering Based Immunoassays

TitleMixed Monolayers on Gold Nanoparticle Labels for Multiplexed Surface-Enhanced Raman Scattering Based Immunoassays
Publication TypeJournal Article
Year of Publication2009
AuthorsWang GF, Park HY, Lipert RJ
Journal TitleAnalytical Chemistry
Volume81
Pages9643-9650
Date Published12/01
ISBN Number0003-2700
Accession NumberISI:000272084700021
Keywordsavium subsp paratuberculosis, colloidal silver particles, DNA, identification, immunogold labels, large ag nanocrystals, molecules, nucleic-acids, sers, spectroscopic tags
Abstract

This paper describes a new approach, based on self-assembled mixed monolayers, to the design and preparation of extrinsic Raman labels (ERLs). ERLs function as spectroscopic tags for the readout of sandwich-type immunoassays using surface-enhanced Raman scattering (SERS). They are created by coating gold nanoparticles with Raman reporter molecules and antibodies specific for the target analyte. Mixed-monolayer ERLs are formed by coveting gold nanoparticles with a mixture of two different thiolates. One thiolate serves to covalently bind antibodies to the particles, imparting biospecificity to the ERLs, while the other thiolate produces a strong Raman signal. Mixed-monolayer ERLs can be prepared in a few relatively simple steps using readily available materials. The SERS intensity of each type of ERL can be tuned to match other ERLs by adjusting the mixed monolayer composition, greatly facilitating the generation of sets of ERLs for multiplexed applications. The work herein not only describes the new pathway for ERL production, but also demonstrates the simultaneous qualitative and quantitative multiplexed detection using a set of four mixed-monolayer ERLs.

URL<Go to ISI>://000272084700021
DOI10.1021/Ac901711f