Photoactivatable Fluorophores for Bioimaging Applications

Abstract

Photoactivatable fluorophores provide the opportunity to switch fluorescence on exclusively in a selected area within a sample of interest at a precise interval of time. Such a level of spatiotemporal fluorescence control enables the implementation of imaging schemes to monitor dynamic events in real time and visualize structural features with nanometer resolution. These transformative imaging methods are contributing fundamental insights on diverse cellular processes with profound implications in biology and medicine. Current photoactivatable fluorophores, however, become emissive only after the activation event, preventing the acquisition of fluorescence images and, hence, the visualization of the sample prior to activation. We developed a family of photoactivatable fluorophores capable of interconverting between emissive states with spectrally resolved fluorescence, instead of switching from a nonemissive state to an emissive one. We demonstrated that our compounds allow the real-time monitoring of molecules diffusing across the cellular blastoderm of developing embryos as well as of polymer beads translocating along the intestinal tract of live nematodes. Additionally, they also permit the tracking of single molecules in the lysosomal compartments of live cells and the visualization of these organelles with nanometer resolution. Indeed, our photoactivatable fluorophores may evolve into invaluable analytical tools for the investigation of the fundamental factors regulating the functions and structures of cells at the molecular level.

RETRACTED: Extracellular Vesicles Embedded with Persistent Luminescence Nanoparticles Exhibiting Near-Infrared Emission for Long-Term Tracking in Primary Tumors

“…The cells were initially transfected with a plasmid carrying the gene encoding green fluorescent protein (GFP). 37 The TCE system allows the direct delivery of DNA into the cytoplasm of cells via nanochannels, thereby accelerating the rate of DNA transcription and translation. 38 The dose can be regulated by altering the number of pulses and voltage.…”

Fluorescence Imaging Enhanced by Members of the Graphene Family: A Review

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No-wash fluorogenic labeling of proteins for reversible photoswitching in live cells

“…The use of photoswitchable uorescent molecules (PSFMs) for tracking cellular dynamics 1 and visualizing cellular components with high spatial resolution using super-resolution imaging [2][3][4][5][6] has greatly increased in recent years. While photoactivatable uorophores irreversibly photoswitch from non-uorescent to uorescent states upon light irradiation, [7][8][9][10][11][12] PSFMs exhibit reversible uorescence switching upon light irradiation allowing each PSFM to be localized multiple times. This is useful for live-cell studies where molecular dynamics can be visualized over long periods.…”