Mapping light distribution in tissue by using MRI-detectable photosensitive liposomes
Author(s)
Simon, Jacob; Schwalm, Miriam; Morstein, Johannes; Trauner, Dirk; Jasanoff, Alan
DownloadSimon2023NatBiomedEng_accepted.pdf (3.038Mb)
Open Access Policy
Open Access Policy
Creative Commons Attribution-Noncommercial-Share Alike
Terms of use
Metadata
Show full item recordAbstract
Characterizing sources and targets of illumination in living tissue is challenging. Here we show that spatial distributions of light in tissue can be mapped by using magnetic resonance imaging (MRI) in the presence of photosensitive nanoparticle probes. Each probe consists of a reservoir of paramagnetic molecules enclosed by a liposomal membrane incorporating photosensitive lipids. Incident light causes the photoisomerization of the lipids and alters hydrodynamic exchange across the membrane, thereby affecting longitudinal relaxation-weighted contrast in MRI. We injected the nanoparticles into the brains of live rats and used MRI to map responses to illumination profiles characteristic of widely used applications of photostimulation, photometry and phototherapy. The responses deviated from simple photon propagation models and revealed signatures of light
scattering and nonlinear responsiveness. Paramagnetic liposomal nanoparticles may enable MRI to map a broad range of optical phenomena in deep tissue and other opaque environments.
Date issued
2022-12-22Journal
Nature Biomedical Engineering
Publisher
Springer Science and Business Media LLC
Citation
Simon, J., Schwalm, M., Morstein, J. et al. Mapping light distribution in tissue by using MRI-detectable photosensitive liposomes. Nat. Biomed. Eng 7, 313–322 (2023).
Version: Author's final manuscript
ISSN
2157-846X
Keywords
Computer Science Applications, Biomedical Engineering, Medicine (miscellaneous), Bioengineering, Biotechnology