title: LSPR Biosensor Signal Enhancement Using Nanoparticle-Antibody Conjugates.
abstract: A method to amplify the wavelength shift observed from localized surface plasmon resonance (LSPR) bioassays is developed using gold nanoparticle-labeled antibodies. The technique, which involves detecting surface-bound analytes using gold nanoparticle conjugated antibodies, provides a way to enhance LSPR shifts for more sensitive detection of low-concentration analytes. Using the biotin and antibiotin binding pair as a model, we demonstrate up to a 400% amplification of the shift upon antibody binding to analyte. In addition, the antibody-nanoparticle conjugate improves the observed binding constant by 2 orders of magnitude, and the limit of detection by nearly 3 orders of magnitude. This amplification strategy provides a way to improve the sensitivity of plasmon-based bioassays, paving the way for single molecule-based detection and clinically relevant diagnostics.
authors.affiliation: Department of Chemistry, Northwestern University, 2145 North Sheridan Road, Evanston, Illinois 60208, United States.
authors.forename: W Paige
authors.initials: WP
authors.lastname: Hall
authors.forename: Salome N
authors.initials: SN
authors.lastname: Ngatia
authors.forename: Richard P
authors.initials: RP
authors.lastname: Van Duyne