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bioRxiv · 10.1101/626853

Photoactivation of silicon rhodamines via a light-induced protonation

Frei, M. S.·Hoess, P.·Lampe, M.·Nijmeijer, B.·Kueblbeck, M.·Ellenberg, J.·Ries, J.·Pitsch, S.·Reymond, L.·Johnsson, K.
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Abstract

We present a new type of photoactivatable fluorophore that forms a bright silicon rhodamine derivative through a light-dependent isomerization followed by protonation. In contrast to other photoactivatable fluorophores, no caging groups are required, nor are there any undesired side-products released. Using this photoactivatable fluorophore, we created probes for HaloTag and actin for live-cell single-molecule localization microscopy and single-particle tracking experiments. The unusual mechanism of photoactivation and the fluorophores outstanding spectroscopic properties make it a powerful tool for live-cell super-resolution microscopy.

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Frei, M. S., Hoess, P., Lampe, M., Nijmeijer, B., Kueblbeck, M., Ellenberg, J., Ries, J., Pitsch, S., Reymond, L., Johnsson, K.. 2019-05-04. Photoactivation of silicon rhodamines via a light-induced protonation. https://doi.org/10.1101/626853

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