A Minireview on the Applications of Nanobiosensors Based on Localized Surface Plasmon Resonance Phenomenon

Abstract

In this new era of nano-materials, most chemists and physicists are familiar with the phenomenon of localized surface plasmon resonance (SPR). Noble-metal nano-particles with dimensions (3–100 nm) much smaller than the wavelength of incident light (400–900 nm) exhibit this tendency. In nanostructured materials, due to their very small particle size, the electrons are restricted within the nanoparticle surface area and oscillate with a certain frequency. It is noteworthy that the phenomenon of localized surface plasmon resonance appears when the frequency of the incoming photons overlaps with the frequency of the electrons. As this oscillation of surface electrons is taking place against the restoring forces of the positive nuclei, there is a formation of plasmon resonance. This characteristic property of scattering and absorption of photons appearing in the SPR of every nano-structured material, make them excellent nanoprobes for a variety of applications such as cell imaging and detection of protein phosphorylation and many others. The performance of bio-chemical sensing devices has been greatly improved by the development of localized surface plasmon resonance (SPR) based sensors. In the present minireview, we have briefly discussed the classification of biosensors and the basics of their instrumentation. Some of these applications have been discussed here using some nano-engineered biosensors.