Microspectroscopy

Microspectroscopy involves the quantitative measurement of the intensity of light scattered at discrete wavelengths from different points in a sample. Typically, a single frequency laser is focused on a sample and the scattered light from this point is collected (usually in an epi-detection confocal setup) and passed to a spectrometer where it is spectrally analyzed. The sample or the position of the focused point on the sample may then be translated (in 2D or 3D) to produce a multi-dimensional data set that consists of the measured scattering spectra at each point.

Different parts of the spectra give different information on the properties of the sample. At larger wavelength-shifts from the probing laser wavelength one can obtain information on the chemical composition (e.g. lipid, protein content) – so-called “Raman Spectra”. At smaller wavelength shifts one can obtain information on the viscoelasticity (elastic storage and loss moduli) from the so-called “Brillouin Spectra”. The Advanced Microscopy Facility offers the possibility to measure both of these spectra. In addition, it also offers the possibility to measure the fluorescence signal of certain molecules in parallel to allow e.g. for correlative studies of the mechanical properties and abundance of specific labelled molecules. We also offer certain variations on the above techniques, which can be useful for addressing specific questions.

 

What information is contained in the scattering spectra / what can I learn?

 

 

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