Absorption by water increases fluorescence image contrast of biological tissue in the shortwave infrared
Abstract
Shortwave infrared (SWIR) fluorescence imaging is a tool for visualizing biological processes deep within tissue or living animals. Our study shows that the contrast in a SWIR fluorescence image is primarily mediated by the absorptivity of the tissue, and can therefore be tuned through deliberate selection of imaging wavelength. We show, for example, that, in 3D tissue phantoms and in brain vasculature in vivo in mice, imaging at SWIR wavelengths of the highest water absorptivity results in the greatest fluorescence contrast. We further demonstrate, in microscopy of ex vivo mouse liver tissue, that imaging at wavelengths of high tissue absorptivity can also increase imaging penetration depth, and use a theoretical contrast model to explain this effect.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 27, 2018
- Source ID
- 10.1073/pnas.1803210115
Entities
People
- Daniel Franke
- Jessica A Carr
- Marianne Aellen
- Moungi Bawendi
- Oliver T. Bruns
- Peter T. C. So
Organizations
- Air Force Office of Scientific Research
- Boehringer Ingelheim Fonds
- ETH Zurich
- European Molecular Biology Organization
- Massachusetts Institute of Technology
- National Institutes of Health
- National Science Foundation