Nanoarray-Based Biomolecular Detection Using Individual Au Nanoparticles with Minimized Localized Surface Plasmon Resonance Variations

摘要

ABSTRACT: Here, we present a mean to expand the use ofnindividual metallic nanoparticles to two-dimensional plasmonicnnanoarrays. An optical detection platform to track downnlocalized surface plasmon resonance (LSPR) signals of indivi-ndual nanoparticles on substrates was built for the application ofnplasmonic nanoarrays. A pseudoimage of nanoparticles on ansubstrate was reconstructed from their scattering spectra ob-ntained by scanning a user-defined area. The spectral and spatialnresolutions of the system were also discussed in detail. Most importantly, we present a method to normalize the localized surfacenplasmon resonance from geometrically different nanoparticles. After normalization, plasmonic responses from different particlesnbecome highly consistent, creating well-fitted dose-response curves of both surrounding refractive index changes and receptor-nanalyte binding to the surface of individual nanoparticles. Finally, the proof-of-concept system for plasmonic nanoarray detection isndemonstrated by the measurement of the aptamer-thrombin binding event.