Supramolecular Control of Helicene Circularly Polarized Luminescence Emitters in Molecular Solids and Bright Nanoparticles.

Circularly polarized luminescence (CPL) from chiral molecules is attracting much attention due to its potential use in optical materials. However, formulation of CPL emitters as molecular solids typically deteriorates photophysical properties in the aggregated state leading to quenching and unpredictable changes in CPL behavior impeding materials development. To circumvent these shortcomings, a supramolecular approach can be used to isolate cationic dyes in a lattice of cyanostar-anion complexes that suppress aggregation-caused quenching and which we hypothesize can preserve the synthetically-crafted chiroptical properties.

Photophysics of fluorescent nanoparticles based on organic dyes - challenges and design principles.

Fluorescent nanoparticles have become attractive for bioanalysis and imaging, due to their high brightness and photostability. Many different optical materials have been applied in fluorescent nanoparticles with a broad range of properties and characteristics. One appealing approach is the incorporation of molecular organic fluorophores in nanoparticles with the intention of transferring their known attractive solution-state properties directly to the nanoparticles.

Control of the fluorescence lifetime in dye based nanoparticles.

Fluorescent dye based nanoparticles (NPs) have received increased interest due to their high brightness and stability. In fluorescence microscopy and assays, high signal to background ratios and multiple channels of detection are highly coveted. To this end, time-resolved imaging offers suppression of background and temporal separation of spectrally overlapping signals.

Cellular Visualization of G-Quadruplex RNA via Fluorescence- Lifetime Imaging Microscopy.

Over the past decade, appreciation of the roles of G-quadruplex (G4) structures in cellular regulation and maintenance has rapidly grown, making the establishment of robust methods to visualize G4s increasingly important. Fluorescent probes are commonly used for G4 detection in vitro; however, achieving sufficient selectivity to detect G4s in a dense and structurally diverse cellular environment is challenging. The use of fluorescent probes for G4 detection is further complicated by variations of probe uptake into cells, which may affect fluorescence intensity independently of G4 abundance.

Universal Concept for Bright, Organic, Solid-State Emitters─Doping of with FRET Acceptors.

Brightly fluorescent solid-state materials are highly desirable for bioimaging, optoelectronic applications, and energy harvesting. However, the close contact between π-systems most often leads to quenching. Recently, we developed (SMILES) that efficiently isolate fluorophores while ensuring very high densities of the dyes.