The role and importance of mechanical properties of cells and tissues in cellular function, development and disease has widely been acknowledged, however standard techniques currently used to assess them exhibit intrinsic limitations. Recently, Brillouin microscopy, a type of optical elastography, has emerged as a non-destructive, label- and contact-free method that can probe the viscoelastic properties of biological samples with diffraction-limited resolution in 3D. This led to increased attention amongst the biological and medical research communities, but it also sparked debates about the interpretation and relevance of the measured physical quantities. Here, we review this emerging technology by describing the underlying biophysical principles and discussing the interpretation of Brillouin spectra arising from heterogeneous biological matter. We further elaborate on the technique’s limitations, as well as its potential for gaining insights in biology, in order to guide interested researchers from various fields.
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We thank G. Scarcelli and C. J. Chan for insightful discussions and feedback on the manuscript, Q. Yang and P. Liberali (Friedrich Miescher Institute, Basel) as well as V. de Turris and A. Rosa (Istituto Italiano di Tecnologia, Roma) for providing the samples shown in Fig. 5a and c, respectively; and C. Bevilacqua and M. Bergert for help with figures. This work was supported by the European Molecular Biology Laboratory (R.P., A.D.-M.), the COST Action CA16124 (‘BioBrillouin’) and the Deutsche Forschungsgemeinschaft (DFG) research grant DI 2205/2-1 (A.D.-M.).
The authors declare no competing interests.
Peer review information: Nina Vogt was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.
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Prevedel, R., Diz-Muñoz, A., Ruocco, G. et al. Brillouin microscopy: an emerging tool for mechanobiology. Nat Methods 16, 969–977 (2019). https://doi.org/10.1038/s41592-019-0543-3
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