Raman spectroscopy and microscopy
Raman spectroscopy and microscopy
Raman spectroscopy is one of the main vibrational spectroscopic techniques, in which the spectra of the observed samples are obtained as a result of vibrations of bonds between atoms in sample molecules. It is a non-destructive chemical analytical technique that uses inelastic light scattering to identify a unique fingerprint of a molecule. With the interaction of a monochromatic light source (in the area of the visible, close infrared or close ultraviolet part of the spectrum) and the pattern, there is a so-called inelastic scattering of light, in which the output photons have a different wavelength from the input (Raman effect). By detecting scattered photons, a spectrum is obtained in which Raman displacement is displayed along with the intensity of the detected photons.
Since the displayed ribbons in the spectrum correspond to the connections of atoms within the molecules, a quick identification of the material is possible using the relationship of the specific positions and intensity of the ribbons in the Raman spectrum. Furthermore, given that the intensity of individual ribbons in the spectrum can be linked to the concentration of analytes in the sample, qualitative and quantitative determination of analytes is possible.
Raman microscopy combines Raman spectroscopy with optical microscopy, allowing the spatial determination of the different components within the observed sample in three dimensions and obtaining of a so-called chemical imaging of the cross-section, with resolution up to 1μm.
Raman spectroscopy and microscopy are used in research in the fields of nanotechnology, electronics, materials science, pharmacy, geology...
Pharmaceutical industry:
Potential applications in the detection and development of drugs:
testing the distribution of components within the formulations,
characterisation of the homogeneity of pharmaceutical samples,
determination of the condition of medicinal substances and excipients and
characterisation of pollution and foreign particulate matter
Raman spectroscopy methods are also applied for:
design of medicinal substance,
development of solid and liquid formulations,
as a process analytics tool
to determine patent infringements
falsification analysis
Material analysis:
chemical and structural analysis of multidimensional materials
ideal choice for determining the thickness of a layer of graphene and determining the relative diameter of carbon nanotubes
Battery development:
real-time analysis of structural and material changes on lithium-ion batteries
perfect for effective ex situ analysis of anodic and cathodic materials
Polymer/packaging analysis:
visualization of 3D confocal spectral data
fast understanding of multi-layered patterns at high resolution
obtaining data on structure and crystallinity
Determination of microplastics:
microplastics: automated analysis and identification of multi-point microplastics,
advanced software for optical location, characterization and identification of microplastics
higher spatial resolution allows microparticle analysis
Geological surveys:
rapid non-destructive identification of liquid inclusions in minerals
current data on crystallinity and crystal structure
Restoration of art and the study of cultural art:
identifying and characterising the original and decomposed compounds present in art objects and archaeology
non-invasive, non-destructive pigment analysis method
Forensic science:
Applications within forensic science include the identification of illegal drugs, shooting residues, accelerants in cases of arson, ink used for counterfeiting or explosives.
Sample Control uses the most technologically advanced Raman microscope in its work. The Thermo Scientific™ DXR™3xi Raman Imaging microscope significantly expands the analyses carried out by Sample Control Laboratory.
As part of the analyses on the Raman microscope, at the moment we perform a large number of methods, several of which are accredited or in the process of accreditation, while some methods are innovative and subject to research and development. Some of the methods we use:
Identification of materials
Determination of microplastics in drinking water and seawater
Determination of microplastics in food and dietary supplements
Determination of microplastics in cosmetic products
Application of chemometric techniques for quantitative determination of analytes in solutions
Detection of SERS (Surface Enhanced Raman Spectroscopy) contaminants
