Four systems 1a - d were prepared to investigate the optical properties of copolymers comprised of polyfluorene doped with BODIPY-based fluors. The underlying hypothesis was energy harvested via the strong absorptivity of the major component, fluorine, would be primarily emitted from the BODIPY parts at much higher wavelengths. Optimization of the polymerization process as a function of the mol % of BODIPY, indicated that the brightest polymers were formed when approximately 4 fluorene units were co-polymerized with every BODIPY precursor.
View Article and Find Full Text PDFPhotophysical data and orbital energy levels (from electrochemistry) were compared for molecules with the same BODIPY acceptor part (red) and perpendicularly oriented xanthene or BODIPY donor fragments (green). Transfer of energy, hence the photophysical properties of the cassettes, including the pH dependent fluorescence in the xanthene-containing molecules, correlates with the relative energies of the frontier orbitals in these systems. Intracellular sensing of protons is often achieved via sensors that switch off completely at certain pH values, but probes of this type are not easy to locate inside cells in their "off-state".
View Article and Find Full Text PDFTo understand the effects of substitution patterns on photosensitizing the ability of boron dipyrromethene (BODIPY), two structural variations that either investigate the effectiveness of various iodinated derivatives to maximize the "heavy atom effect" or focus on the effect of extended conjugation at the 4-pyrrolic position to red-shift their activation wavelengths were investigated. Compounds with conjugation at the 4-pyrrolic position were less photocytotoxic than the parent unconjugated compound, while those with an iodinated BODIPY core presented better photocytotoxicity than compounds with iodoaryl groups at the meso-positions. The potency of the derivatives generally correlated well with their singlet oxygen generation level.
View Article and Find Full Text PDFFluorescent probes 1 and 2 were prepared directly from tetramethyl-BODIPY via palladium-mediated C-H functionalization reactions.
View Article and Find Full Text PDF