Comperative i̇nvestigation of localized surface plasmon resonance spectroscopy and surface plasmon resonance spectroscopy in sensor application

Nowadays, Surface Plasmon Resonance Spectroscopy (SPR) and Localized Surface Plasmon Resonance Spectroscopy (LSPR), has been increasing application area, such as Nanotechnology, Biosensors, Chemical Sensors, Materials science, Medicine and Health, Environmental Science, Kinetic Analysis and Biomolecular Interactions. Thanks to their sensitivity and specificity, they have become indispensable tools for scientific research and industrial applications. Surface Plasmon Resonance Spectroscopy (SPR), which is based on the principle that a plasmon excited by an electromagnetic wave at the dielectric interface with a metal surface resonates and a large part of the light coming at a certain angle is used to create surface plasmons, reduces the reflected light to a minimum level and its intensity is measured by a detector, at the same time. It also enables the detection and analysis of biomolecular interactions on the surface without labeling. Localized Surface Plasmon Resonance Spectroscopy (LSPR), which examines the stimulation of the collective oscillation of electrons on the nanoparticle surface by light waves interacting with nanoscale metallic structures (usually gold or silver), investigates their optical properties, such as the absorption of light by nanoparticles when the oscillating electrons resonate. In this study, which is about the comparative examination of SPR and LSPR, first of all, for a single metal sphere irradiated with nano-sized y-emission z-polarization embedded in an external medium (i.e. vacuum, gas or liquid), the wavelength of the laser light used is λ, the dielectric constant of the medium ε_0, the dielectric constant of the sphere ε_1, the theoretical infrastructure of Localized Surface Plasmon Spectroscopy (LSPR) for this spherical structure will be examined and in this context, the relevant Maxwell Equations will be solved and the suitability of these two methods for nanostructures will be discussed. Keywords: Plasmon, Resonance spectroscopy, Maxwell's Equations, Localized surface plasmon, Surface plasmon