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Two- and three-photon absorption cross-section characterization for high-brightness, cell-specific multiphoton
Aleksandr A Lanin1,2, Artem S Chebotarev1, Matvei S Pochechuev1,3
1Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia.
Journal of Biophotonics
|October 1, 2019
Summary
This study characterizes the high two-photon and three-photon absorption of Sypher3s, a fluorescent marker ideal for bright brain imaging. Its pH sensitivity also enables deep-tissue optical pH sensing.
Area of Science:
- Biophotonics
- Molecular Imaging
- Fluorescence Microscopy
Background:
- Genetically encodable fluorescent markers are crucial for cellular and tissue imaging.
- Accurate characterization of photophysical properties like two-photon and three-photon absorption (2PA and 3PA) is essential for advanced imaging techniques.
Purpose of the Study:
- To quantitatively characterize the absolute 2PA and 3PA action cross sections of the genetically encodable fluorescent marker Sypher3s.
- To demonstrate the utility of Sypher3s for high-brightness, cell-specific two- and three-photon fluorescence brain imaging.
- To explore the potential of Sypher3s for pH sensing applications in biological tissues.
Main Methods:
- Quantitative characterization of absolute 2PA and 3PA action cross sections.
- In vitro and in vivo fluorescence imaging experiments using Sypher3s.
- pH sensitivity measurements using ratiometric two-photon fluorescence.
Main Results:
- Sypher3s exhibits remarkably high 2PA and 3PA action cross sections.
- High-brightness, cell-specific two- and three-photon fluorescence brain imaging was achieved in rat cortical slices.
- The 2PA action cross section of Sypher3s demonstrated high sensitivity to pH levels.
Conclusions:
- Sypher3s is a highly efficient fluorescent marker for advanced multiphoton brain imaging.
- The pH sensitivity of Sypher3s opens avenues for developing novel optical pH sensors for deep-tissue applications.
