Quantifying local stiffness and forces in soft biological tissues using droplet optical microcavities

• 成果类型: Article
• 署名作者: Pirnat, Gregor; Marincic, Matevz; Ravnik, Miha; Humar, Matjaz
• 署名单位: Slovenian Academy of Sciences & Arts (SASA); Jozef Stefan Institute; University of Ljubljana
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12405
• DOI: 10.1073/pnas.2314884121
• 发表日期: 2024-01-23
• 关键词: brain-tissue; mechanical-properties; cell; microdroplet; spectroscopy; microscopy; emission; tension; field

摘要

Mechanical properties of biological tissues fundamentally underlie various biological processes and noncontact, local, and microscopic methods can provide fundamental insights. Here, we present an approach for quantifying the local mechanical properties of biological materials at the microscale, based on measuring the spectral shifts of the optical resonances in droplet microcavities. Specifically, the developed method allows for measurements of deformations in dye-doped oil droplets embedded in soft materials or biological tissues with an error of only 1 nm, which in turn enables measurements of anisotropic stress inside tissues as small as a few pN/mu m(2). Furthermore, by applying an external strain, Young's modulus can be measured in the range from 1 Pa to 35 kPa, which covers most human soft tissues. Using multiple droplet microcavities, our approach could enable mapping of stiffness and forces in inhomogeneous soft tissues and could also be applied to in vivo and single-cell experiments. The developed method can potentially lead to insights into the mechanics of biological tissues.