Nanoplasmonic sensor for chemical measurements

In this paper plasmonic nanoparticles arranged in an array configuration for the detection of glycerol concentration in aqueous solution, are presented. Glycerol concentration measurement is crucial for several application fields, such as biomedical engineering, medicine and biofuels fabrication. The detection of glycerol presence in aqueous solution is not simple, due to the fact that its refractive index shows small changes when different concentrations are considered. For this purpose, an LSPR (Localized Surface Plasmon Resonance) sensor, based on near field interaction of non-spherical dielectric-filled metallic particles (nanoshell) deposited on a silica substrate, is proposed. In this configuration an enhancement of the LSPR phenomenon with high sensitivity performances and a uniform near electric field distribution are obtained. In this way a shift in the position of the sensor response is related to the different concentration of the material under test. Numerical results, performed by full-wave simulations, show that the sensor can be used for the recognition of glycerol and its concentration in a highly accurate and sensitive way.