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

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.