The goal of this research program is to explore new laser technologies, new spectral windows, and three- photon fluorescence microscopy for imaging deep into scattering tissues, and then demonstrate the new methodologies in in vivo biological imaging. The proposed research consists of two sequential thrusts: the first involves the development of a novel energetic excitation source for the exploration of the new spectral window between 1600 and 1800 nm (i.e., the 1700-nm spectral window) with significantly reduced tissue scattering;the second thrust concentrates on demonstrating the new methodologies for in vivo deep tissue imaging based on three-photon excitation, improving the signal-to-background ratio by orders of magnitude and extending the depth penetration of multiphoton imaging. The proposed program is based on three major innovations: (1) 1700-nm spectral window for significantly reduced tissue scattering, (2) 3PE as a new excitation modality to simultaneously improve the SBR and extend the accessibility of fluorophores in deep tissue imaging, and (3) an excitation source tailored for in vivo deep tissue three-photon fluorescence microscopy at the 1700-nm spectral window by using soliton self-frequency shift in a photonic crystal rod to generate energetic, wavelength tunable solitons seeded from a fiber laser.
We aim to demonstrate a new generation of multiphoton microscopic imaging tool that can reach an ultimate imaging depth of 3 mm or beyond within intact biological tissues such as the mouse or rat brain. The successful completion of this program will have a broad impact on a wide variety of biological and biomedical research fields where high-resolution imaging deep within intact tissue is required.

Public Health Relevance

The proposed program, if successfully completed, leads to a new generation of multiphoton microscopic imaging tool that can reach an ultimate imaging depth of 3 mm or beyond within intact biological tissues such as the mouse or rat brain. The successful completion of this program will have a broad impact on a wide variety of biological and biomedical research fields where high-resolution imaging deep within intact tissue is required.

Agency
National Institute of Health (NIH)
Type
Research Project (R01)
Project #
5R01EB014873-03
Application #
8604711
Study Section
Enabling Bioanalytical and Imaging Technologies Study Section (EBIT)
Program Officer
Conroy, Richard
Project Start
Project End
Budget Start
Budget End
Support Year
3
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Cornell University
Department
Engineering (All Types)
Type
Biomed Engr/Col Engr/Engr Sta
DUNS #
City
Ithaca
State
NY
Country
United States
Zip Code
14850
Horton, Nicholas G; Xu, Chris (2015) Dispersion compensation in three-photon fluorescence microscopy at 1,700 nm. Biomed Opt Express 6:1392-7
Sinefeld, David; Paudel, Hari P; Ouzounov, Dimitre G et al. (2015) Adaptive optics in multiphoton microscopy: comparison of two, three and four photon fluorescence. Opt Express 23:31472-83
Horton, Nicholas G; Wang, Ke; Kobat, Demirhan et al. (2013) In vivo three-photon microscopy of subcortical structures within an intact mouse brain. Nat Photonics 7:
Xu, C; Wise, F W (2013) Recent Advances in Fiber Lasers for Nonlinear Microscopy. Nat Photonics 7: