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bioRxiv · 10.1101/2024.02.13.580074

Photo-Uncaging Triggers on Self-Blinking to Control Single-Molecule Fluorescence Kinetics for Super-Resolution Imaging

Zheng, Y.·Ye, Z.·Zhang, X.·Xiao, Y.
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Abstract

Super-resolution imaging in a single-molecule localization approach has transformed the bulk fluorescence requirements to a single-molecule level, raising a revolution in the fluorophore engineering. Yet, it is a challenge to structurally devise fluorophores manipulating the single-molecule blinking kinetics. In this pursuit, we have developed a new strategy by innovatively integrating the photoactivatable nitroso-caging strategy into self-blinking sulfonamide, to forming a nitroso-caged sulfonamide rhodamine (NOSR). Our fluorophore demonstrated controllable self-blinking events upon photo-triggered uncaging release. This exceptional blink kinetics improved integrity in super-resolution imaging microtubules compared to self-blinking analogues. With the aid of paramount single-molecule fluorescence kinetics, we successfully reconstructed the axial morphology of mitochondrial outer membranes. We foresee that our synthetic approach of photoactivation and self-blinking would set a new avenue for devising rhodamines for super-resolution imaging. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/580074v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@18d51d5org.highwire.dtl.DTLVardef@f7a1cdorg.highwire.dtl.DTLVardef@19fcc7dorg.highwire.dtl.DTLVardef@2a5bcb_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Zheng, Y., Ye, Z., Zhang, X., Xiao, Y.. 2024-02-15. Photo-Uncaging Triggers on Self-Blinking to Control Single-Molecule Fluorescence Kinetics for Super-Resolution Imaging. https://doi.org/10.1101/2024.02.13.580074

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