Abstract: “The signal enhancement using the evanescent electric field monitoring in the gold nanoparticles (AuNPs) filled surface plasmon resonance (SPR) biosensing is of interest here. The profiles of average evanescent electric fields in a direction normal to the gold/saline layer interface of the 2-dimensional (2D) system are generated at various surface AuNP densities. The shift of the corresponding power density profile increases consistently with the density. The SPR curves associated with dielectric effects from AuNPs are next determined. It shows that the SPR curve shift also possesses the similar characteristic to that of the evanescent field. The evanescent field approach may thus be a potential tool for analyzing SPR signal enhancement.”

Keywords: Electric field distribution, Gold nanoparticles, Maxwell-Garnett, SPR enhancement, Surface plasmon resonance