Deuteration improves small-molecule fluorophores

Grimm, J. B.; Xie, L.; Casler, J. C.; Patel, R.; Tkachuk, A. N.; Choi, H.; Lippincott-Schwartz, J.; Brown, T. A.; Glick, B. S.; Liu, Z.; Lavis, L. D.

doi:10.1101/2020.08.17.250027

bioRxiv · 10.1101/2020.08.17.250027

Deuteration improves small-molecule fluorophores

Grimm, J. B.·Xie, L.·Casler, J. C.·Patel, R.·Tkachuk, A. N.·Choi, H.·Lippincott-Schwartz, J.·Brown, T. A.·Glick, B. S.·Liu, Z.·Lavis, L. D.

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Abstract

Fluorescence microscopy relies on dyes that absorb short-wavelength photons and emit longer-wavelength light. In addition to this fluorescence process, dyes can undergo other photochemical reactions that result in spectral shifts and irreversible photobleaching. Increases in brightness, chromostability, and photostability of fluorescent dyes are therefore crucial for advancing the frontier of bioimaging. Here, we describe a general approach to improve small-molecule fluorophores using deuteration. Incorporating deuterium into the alkylamino substituents of rhodamines and other dyes improves fluorescence quantum yield, inhibits photochemically induced spectral shifts, and slows irreparable photobleaching. These compounds are easily synthesized and show improved performance in cellular imaging experiments.

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Grimm, J. B., Xie, L., Casler, J. C., Patel, R., Tkachuk, A. N., Choi, H., Lippincott-Schwartz, J., Brown, T. A., Glick, B. S., Liu, Z., Lavis, L. D.. 2020-08-17. Deuteration improves small-molecule fluorophores. https://doi.org/10.1101/2020.08.17.250027

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