Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published April 7, 2021 | Supplemental Material + Published
Journal Article Open

Toward photoswitchable electronic pre-resonance stimulated Raman probes


Reversibly photoswitchable probes allow for a wide variety of optical imaging applications. In particular, photoswitchable fluorescent probes have significantly facilitated the development of super-resolution microscopy. Recently, stimulated Raman scattering (SRS) imaging, a sensitive and chemical-specific optical microscopy, has proven to be a powerful live-cell imaging strategy. Driven by the advances of newly developed Raman probes, in particular the pre-resonance enhanced narrow-band vibrational probes, electronic pre-resonance SRS (epr-SRS) has achieved super-multiplex imaging with sensitivity down to 250 nM and multiplexity up to 24 colors. However, despite the high demand, photoswitchable Raman probes have yet to be developed. Here, we propose a general strategy for devising photoswitchable epr-SRS probes. Toward this goal, we exploit the molecular electronic and vibrational coupling, in which we switch the electronic states of the molecules to four different states to turn their ground-state epr-SRS signals on and off. First, we showed that inducing transitions to both the electronic excited state and triplet state can effectively diminish the SRS peaks. Second, we revealed that the epr-SRS signals can be effectively switched off in red-absorbing organic molecules through light-facilitated transitions to a reduced state. Third, we identified that photoswitchable proteins with near-infrared photoswitchable absorbance, whose states are modulable with their electronic resonances detunable toward and away from the pump photon energy, can function as the photoswitchable epr-SRS probes with desirable sensitivity (<1 µM) and low photofatigue (>40 cycles). These photophysical characterizations and proof-of-concept demonstrations should advance the development of novel photoswitchable Raman probes and open up the unexplored Raman imaging capabilities.

Additional Information

© 2021 Published under license by AIP Publishing. Submitted: 11 January 2021; Accepted: 15 March 2021; Published Online: 2 April 2021. This work was supported by the grants from the National Institutes of Health, Grant No. DP2 GM140919 (to L.W.) and Grant No. R35 GM122567 (to V.V.), and by the start-up fund from the California Institute of Technology (to L.W.). Data Availability: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Attached Files

Published - 5.0043791.pdf

Supplemental Material - supplementary_032802021_final.pdf


Files (3.0 MB)
Name Size Download all
2.5 MB Preview Download
503.5 kB Preview Download

Additional details

August 20, 2023
October 23, 2023