Efficient Singlet Fission in Nanoparticle of Amphipathic Anthracene-Tetracene Dyad with Broadband Light Harvesting Ability

Efficient singlet fission (SF) materials with relatively high triplet state energy and broadband light harvesting ability simultaneously have a greater advantage for its practical application into photovoltaics. Herein, we prepared...

Accessing Lanthanide-based, In Situ Illuminated Optical Turn-On Probes by Modulation of the Antenna Triplet State Energy

Luminescent lanthanides possess ideal properties for biological imaging, including long luminescent lifetimes and emission within the optical window. Here, we report a novel approach to responsive luminescent Tb(III) probes that...

Tuning the Baird aromatic triplet-state energy of cyclooctatetraene to maximize the self-healing mechanism in organic fluorophores

Bright, photostable, and nontoxic fluorescent contrast agents are critical for biological imaging. “Self-healing” dyes, in which triplet states are intramolecularly quenched, enable fluorescence imaging by increasing fluorophore brightness and longevity, while simultaneously reducing the generation of reactive oxygen species that promote phototoxicity. Here, we systematically examine the self-healing mechanism in cyanine-class organic fluorophores spanning the visible spectrum. We show that the Baird aromatic triplet-state energy of cyclooctatetraene can be physically altered to achieve order of magnitude enhancements in fluorophore brightness and signal-to-noise ratio in both the presence and absence of oxygen. We leverage these advances to achieve direct measurements of large-scale conformational dynamics within single molecules at submillisecond resolution using wide-field illumination and camera-based detection methods. These findings demonstrate the capacity to image functionally relevant conformational processes in biological systems in the kilohertz regime at physiological oxygen concentrations and shed important light on the multivariate parameters critical to self-healing organic fluorophore design.

Increasing the anti-Stokes shift in TTA upconversion with photosensitizers showing red-shifted spin-allowed charge transfer absorption but a non-compromised triplet state energy level

Excitation into the 1CT absorption band of a spin–orbit charge transfer ISC triplet photosensitizer increases the anti-Stokes shift in TTA upconversion.