Authors: A. Passeri et al.

Journal: ACS Photonics (2025)

Research Areas: Material Science

Cell Lines: HEK293T

Summary: The authors present a novel correlative microscopy method combining Brillouin microscopy and Raman spectroscopy to better understand the mechanical properties of hydrated biological materials, especially the confounding effect of water content on Brillouin-derived stiffness measurements. They apply this technique to single cells to show that apparent changes in stiffness measured by Brillouin microscopy are strongly influenced by changes in hydration and refractive index—rather than purely by structural or “stiffness” changes per se. By modelling cells as biphasic systems and correlating Raman chemical signatures and phase-holographic thickness measurements, they disentangle hydration effects from true mechanical changes. This allows a more reliable interpretation of Brillouin data for biomechanical studies, improving our ability to map 3D micromechanical properties of cells and other hydrated materials. HoloMonitor M4 is used to measure the cell thickness and optical path.

Keywords: HoloMonitor M4, Brillouin microscopy, Raman spectroscopy, quantitative phase imaging, hydration, cell mechanics, longitudinal modulus, non-invasive imaging, label-free, holographic imaging, morphological monitoring