Raman spectroscopy

SPECTROMETER

LabRAM (HR 800), HORIBA Jobin-Yvon

DESCRIPTION OF THE INSTRUMENT

  • Laser 632 and 785 nm
  • XYZ motorized stage with a resolution of 0.1µm (Linkam)
  • CCD 1024×256 front-illuminated open electrod (Synapse)
  • 3 gratings: 300, 600 and 1800 lines/mm allowing to analyze with a resolution from 4 to 0.5 cm-1
  • SIWFT mode: ultra-fast imaging mode allows the acquisition of molecular map with an integration time per spectrum under 1 second.
  • The DuoScan Technology: provide a rastered macrospot from 100×100 to 3×3 µm depending on the objective
  • Labspec software v5

SAMPLES:

We developed expertise in the analysis of calcified tissues. One of the main advantages of Raman spectroscopy is that sample preparation is not complicated. The HR800 permits to work on fresh or embedded bone samples. We use Polymethyl Metacrylate resin to embed samples.

DATA TREATMENT & ANALYSIS

Since many years, the physico-chemical has become a standard to evaluate the bone quality. We developed functions under Matlab to calculate the physico-chemicals parameters (mineral/organic ratio, type-B carbonate ratio, crystallinity).

We developed expertise in multivariate analysis, especially in Principal Component Analysis and Partial Least Square Discriminant Analysis. We also analyse the structure of mineralized collagen fibres with polarized Raman spectroscopy. 

EXAMPLES

  • Raman imaging using DuoScan technology: spatial distribution of type-B carbonate content of a large area (600×800 µm²) acquired in 4h with a pixel resolution of 30 µm.

  • Polarized Raman spectroscopy: variation of the relative intensity as function of the orientation of the mineralized collagen fibres