Brillouin Technology

Brillouin microscopy is an emerging optical technology that can access the mechanical properties of biological materials in a non-contact, non-invasive, and high-resolution manner. To this end, it is a complement to existing contact-based techniques, such as atomic force microscopy and micropipette aspiration, in many biomedical applications.
Since the technique is still in its nascent stage, we are devoted to the continuous technology innovation by addressing current challenges and limitations. As an example, beyond confocal Brillouin microscope, we have developed Brillouin flow cytometry and line-scanning Brillouin microscopy.
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 Further readings :
Zhang, Scientific Reports, 2016.
Zhang and Scarcelli, Nature Protocols, 2021.
Zhang et al, Nature Methods, 2023.
Kabakova et al, Nature Reviews Methods Primers, 2024.

Cell Biomechanics

Mechanical cues from external microenvironment, together with gene expression and signaling pathways, regulate cell functions and activities through the mechanism of mechanotransduction. In response, cells alter their mechanical properties, suggesting the mechanical signatures are prominent indicators of cell functions and behaviors.
Brillouin technique provides us with a powerful tool to map the mechanical modulus of a cell with sub-um resolution. For the first time, we accessed the nuclear mechanics in intact cells and found the regulation of cytoskeletal network and internal nanostructures. In collaboration with cell biologists, we observed how the cellular/nuclear mechanics regulate tumor cell migration through confined channels as well as transendothelial migration.
​In the future, we will expand the study from 2D to 3D environment and apply the technique to early detection of cancer cells.
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Further readings:
Zhang, Small, 2020.
Wisniewski, Science Advances, 2020.
Roberts, J Biomechanics, 2021.

Tissue Biomechanics

The morphological evolution during embryonic development involves cell alignment and folding as well as tissue reshaping and patterning, accompanied by dramatic mechanical changes of 3D embryonic tissue. We have demonstrated Brillouin technique has good mechanical sensitivity, spatial resolution and penetration depth to quantify tissue mechanics of mouse and chicken embryos at early stages.
Currently, we are working to understand how the tissue mechanics regulates neural tube closure, which is a crucial step for the development of central nervous system, and to fill the gap between the genetic regulation and the mechanical phenotype of embryonic tissue.

Further readings:
Raghunathan, J Biomedical Optics, 2017.
Zhang, Birth Defects Research, 2018. 
Handler, Scientific Reports, 2023.