Achieving optical transparency in live animals with absorbing molecules

Optical imaging plays a central role in biology and medicine but is hindered by light scattering in live tissue. We report the counterintuitive observation that strongly absorbing molecules can achieve optical transparency in live animals. We explored the physics behind this observation and found that when strongly absorbing molecules dissolve in water, they can modify the refractive index of the aqueous medium through the Kramers-Kronig relations to match that of high-index tissue components such as lipids. We have demonstrated that our straightforward approach can reversibly render a live mouse body transparent to allow visualization of a wide range of deep-seated structures and activities. This work…

• NS
  National Science Foundation

  Awards: 2045120, 1542152, 2217582, 1656518, CAREER, ECCS-1542152
• FU
  Focused Ultrasound Foundation
• SN
  Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung

  Award: ECCS-1542152
• NI
  National Institutes of Health

  Award: R01NS126076
• DO
  Division of Electrical, Communications and Cyber Systems

  Awards: ECCS-1542152, 1542152