Surface-enhanced Raman spectroscopy is a highly sensitive method of improving the Raman scattering of molecules supported by nanostructured materials. It means that low concentration analytes can be structurally fingerprinted. This is achieved through chemical enhancement or plasmon-mediated amplification of electrical fields.
Surface enhanced Raman.
Image Credit: Nikalyte Ltd.
In this article, the primary uses and functions of SERS are discussed.
What is Surface Enhanced Raman Spectroscopy?
There are two types of light scattering from molecules: elastic (Rayleigh scattering) and inelastic (Raman scattering). The primary distinction is that in elastic scattering, the scattering events do not affect the photon’s energy or the state of the molecule. This means that the Rayleigh light scattering method reveals little about the states and structures of molecules.
Inelastic scattering occurs when monochromatic light interacts with a molecule's modes and vibrational states. As laser sources have improved, Raman spectroscopy has become an exceedingly sensitive technique; but the low sensitivity and low-scattering cross-sections have restricted the uses of conventional Raman spectroscopy.
Raman spectrum of Fentanyl solution measured at 830nm excitation using Nikalyte's SERS substrates. Image Credit: Nikalyte Ltd.
SERS is a technique that involves molecules undergoing greater scattering efficiencies when adsorbed on metal colloidal nanoparticles and rough metal surfaces.
How it Works
SERS uses silver or gold metal surfaces roughened at the nanoscale. These roughened nanostructures are stimulated by lasers, boosting the surface charges and creating a localized plasmonic light field.
Molecules absorbed by or positioned close to the enhanced field at the surface increase the Raman signal by many orders of magnitude. This increase in Raman signals can detect low concentrations without fluorescent labeling.
Applications of Surface Enhanced Raman Spectroscopy
Illicit Drug Detection
SERS can be used to recognize several illegal substances, including heroin, MDMA, and fentanyl. This is due to the potential to produce a particular molecule. SERS can distinguish between several molecules simultaneously, which is helpful for identifying the components of contaminated street drugs.
Pollution Monitoring in Water
Water quality and contaminant concentrations can be monitored using SERS. It provides a sensitive, versatile, and non-destructive testing method that supplies information on organic and inorganic water pollutants.
SERS is ideal for food inspection due to its readiness, sensitivity, and minimal sample preparation requirements. It can be used to find contaminants like melamine, adulterations, and harmful bacteria in food.
Pharmaceuticals are comprised of several active ingredients, with minuscule levels of the actual drug present. Highly specific analysis and surface enhancement must therefore be done using particular procedures.
Raman spectroscopy is a powerful resource in this situation as it can explain the interactions between the chemical components of the medicine and the pathogenic microbes and organisms.
Surface Enhanced Raman Sensors from Nikalyte
The ground-breaking SERS technology from Nikalyte combines high sensitivity with affordability and simplicity. The distinctive nanoparticle SERS substrates from Nikalyte are extremely sensitive when used with analytes like fentanyl, caffeine, amphetamine, and heroin.
This information has been sourced, reviewed, and adapted from materials provided by Nikalyte Ltd.
For more information on this source, please visit Nikalyte Ltd.