Effect of hydration on plasmonic coupling of bioconjugated gold nanoparticles immobilized on a gold film probed by surface-enhanced Raman spectroscopy.
Gold nanoparticle (AuNP)-Au film constructs were prepared using antibody-antigen interactions or a small organic cross-linker to systematically control the gap between the AuNP and Au film. Surface-enhanced Raman spectroscopy (SERS), scanning electron micrsocopy (SEM), and atomic force microscopy (AFM) were used to characterize each construct and elucidate structure-activity relationships. Interestingly, plasmonic coupling and SERS intensity were reversibly modulated with wetting/drying cycles for the protein immobilized AuNP, and this effect was attributed to changes in protein size with hydration state. This work provides insight into fundamental limitations of AuNP-enabled SERS bioassays and will facilitate rational design of novel biospecific ligands that maximize SERS sensitivity.
Department of Chemistry, Illinois State University , Normal, Illinois 61790, United States.
Jeremy D
JD
Driskell
Carleigh G
CG
Larrick
Christopher
C
Trunell
D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D013059:Spectrum Analysis, Raman
D006046:Gold