Colloidal SERS Substrate for the Ultrasensitive Detection of Biotinylated Antibodies Based on Near-Field Gradient within the Gap of Au Nanoparticle Dimers

MERCADAL, P. A.; ENCINA, E. R.; CORONADO, E. A.

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2019 vol. 123 p. 23577 - 23577

1932-7447

urface-enhanced Raman spectroscopy(SERS) has demonstrated to be a powerful technique forthe ultrasensitive detection of different types of analytes andparticularly biomolecules, with the rational design of SERSsubstrates being one of the most relevant issues for thedevelopment of effective detection protocols. In this work, acolloidal SERS substrate consisting of a pair of Au nanorodslinked by the molecular bridge biotin/streptavidin/biotin hasbeen obtained and employed for the detection of picomolarquantities of the biotinylated antibodies gliadin IgG and Arah1 IgG, which is of great interest in food science. As aconsequence of the bioconjugation strategy implemented, the SERS substrate, that is, the Au nanorod dimer, presents theadvantage of combining in a single nanostructure the capabilities for both direct and indirect detection of the biotinylatedantibodies. Furthermore, the experimental results are supported by detailed electrodynamics simulations which takes intoaccount not on