Brillouin Light Scattering Spectroscopy involves measuring the inelastic scattered light from thermal vibrations. The measured spectra – which is the result of photons coupling to low energy acoustic phonon modes in a sample – is related to the respective phonon velocities, which in turn are related to the high frequency elastic moduli in the probed region. It can thus be used to all optically map the mechanical properties of samples. In a confocal detection scheme these can be measured with near diffraction limited optical resolution in 3 dimensions (Brillouin Microspectroscopy), and depending on the measurement configuration different elastic moduli can be extracted.
An established technique in condensed matter physics, it is only recently gaining popularity for life science and biomedical applications. This is largely due to the realization of improved high resolution sensitive spectrometers together with growing evidence that mechanical properties can play an often critical role for many fundamental biological processes ranging from embryonic development to disease proliferation. Being able to probe these non-invasively and in a label-free manner could thus offer huge potential both in understanding the underlying biophysical mechanisms as well as for future diagnostics.
Though Brillouin Light Scattering Microspectroscopy holds great potential several challenges remain in order for it to become a routine lab tool or diagnostics technique. The BioBrillouin Action network has been setup in order to address these as a community.