Prospects for plasmonic hot spots in single molecule SERS towards the chemical imaging of live cells

Abstract

Single molecule surface enhanced Raman scattering (SM-SERS) is a highly local effect occurring at sharp edges, interparticle junctions and crevices or other geometries with a sharp nanoroughness of plasmonic nanostructures ("hot spots"). The emission of an individual molecule at SM-SERS conditions depends on the local enhancement field of the hot spots, as well as the binding affinity and positioning at a hot spot region. In this regard, the stability of near-field nano-optics at hot spots is critical, particularly in a biological milieu. In this perspective review, we address recent advances in the experimental and theoretical approaches for the successful development of SM-SERS. Significant progress in the understanding of the interaction between the excitation electromagnetic field and the surface plasmon modes at the metallic or metallic/dielectric interface of various curvatures are described. New knowledge on methodological strategies for positioning the analytes for SM-SERS and Raman-assisted SERS or the SERS imaging of live cells has been acquired and displayed. In the framework of the extensive development of SM-SERS as an advancing diagnostic analytical technique, the real-time SERS chemical imaging of intracellular compartments and tracing of individual analytes has been achieved. In this context, we highlight the tremendous potential of SERS chemical imaging as a future prospect in SERS and SM-SERS for the prediction and diagnosis of diseases.

Raman spectroscopy: techniques and applications in the life sciences

“…A great selection of reviews exist which go into further detail than is presented here for other related areas within SERS. These reviews include general overviews [267][268][269][270][271], and reviews specific to cell studies [272][273][274][275], medical applications [24,25,276,277], and toxicology [278,279].…”

Magnetic field concentration with coaxial silicon nanocylinders in the optical spectral range

“…[1][2][3][4]. While performances of conventional optical elements cannot lead to substantial field concentrations below classical diffraction limit, various auxiliary nanostructures, operating with near field, could deliver deep subwavelength enhancement.…”

SERS Detection of Penicillin G Using Magnetite Decorated with Gold Nanoparticles

“…The TEM images ( Figure 2) show that the Au NPs formed larger aggregates at the sorbents surfaces, which have been reported to provide sites of local strong enhancement of the electromagnetic field ("hot spots") within interparticle junctions [54,55]. However, it is not clear that the aggregation state by itself could explain the differences observed in the SERS magnification signal among all the substrates employed.…”