| Abstract
| - Glancing angle deposition was used to produce∼150-nm-thick silver nanoparticle films, which wereevaluated as localized surface plasmon resonance (LSPR)biosensors. The films have a strong extinction peakaround 368 nm in air due to LSPR. As the refractive indexof the surrounding environment is increased, the extinction peak red-shifts with a linear dependence. The filmswere functionalized with 11-amino-1-undecanethiol andrabbit immunoglobulin G (rIgG) to allow for the detectionof anti-rIgG binding. Binding of biomolecules to thenanoparticle surface increases the local refractive indexand results in a red-shifting of the extinction peak. Thewavelength shift at varying concentrations of anti-rIgG wasmeasured and fit to the Langmuir isotherm. This yieldedapproximate values for the saturation response, Δλmax =29.4 ± 0.7nm, and the surface confined binding constant,Ka = (2.7 ± 0.3) × 106 M-1. The response to nonspecificbinding was also investigated.
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