Sensing on Single Plasmonics

Abstract

Plasmonic nanoparticles (Au, Ag, Cu) have attracted increasing attentions due to their excellent optical, chemical and physical characters, especially localized surface plasmon resonance (LSPR) property. Plasmonic nanoparticles have been widely applied in the fields of catalysis, energy sources and various sensors. Notably, the development of optical techniques achieved the investigation of single plasmonic nanoparticles including dark-field microscopy, differential interference contrast (DIC) microscopy and surface plasmon resonance imaging, etc. The single-nanoparticle detection eliminates the average effect compared with bulk system and improves detection sensitivity dramatically, even to single molecule level. Thus, in this chapter, we focus on the determination on a single nanoparticle mainly based on plasmon resonance scattering spectroscopy under dark-field microscopy. The points of morphology and composition modulation, inter-particle coupling, plasmon resonance energy transfer and opto-electrochemical detection are highlighted.