Exploiting radical-pair intersystem crossing for maximizing singlet oxygen quantum yields in pure organic fluorescent photosensitizers.

Fluorescent photosensitizers (PSs) often encounter low singlet oxygen (O) quantum yields and fluorescence quenching in the aggregated state, mainly involving the intersystem crossing process. Herein, we successfully realize maximizing O quantum yields of fluorescent PSs through promoting radical-pair intersystem crossing (RP-ISC), which serves as a molecular symmetry-controlling strategy of donor-acceptor (D-A) motifs. The symmetric quadrupolar A-D-A molecule PTP exhibits an excellent O quantum yield of 97.

Fluorescent nanorods based on 9,10-distyrylanthracene (DSA) derivatives for efficient and long-term bioimaging.

Fluorescent nanoparticles based on 9,10-distyrylanthracene (DSA) derivatives (4,4'-((1E,1'E)-anthracene-9,10-diylbis(ethene-2,1-diyl))bis(N,N-dimethylaniline) (NDSA) and 4,4'-((1E,1'E)-anthracene-9,10-diylbis(ethene-2,1-diyl))dibenzonitrile (CNDSA)) were prepared using an ultrasound aided nanoprecipitation method. The morphologies of the fluorescent nanoparticles could be controlled by adjusting the external ultrasonication time. NDSA or CNDSA could form spherical nanodots (NDSA NDs, CNDSA NDs) in a THF-H2O mixture with an 80% or 70% water fraction when the ultrasonication time was 30 s.

High-efficiency fluorescent and magnetic multimodal probe for long-term monitoring and deep penetration imaging of tumors.

High-quality multimodal imaging requires exogenous contrast agents with high sensitivity, spatial-temporal resolution, and high penetration depth for the accurate diagnosis and surveillance of cancer. Herein, we design a highly efficient fluorescent and magnetic multimodal probe by doping fluorescent molecule 2-(4-bromophenyl)-3-(4-(4-(diphenylamino)styryl)phenyl)fumaronitrile (TB) with near-infrared (NIR) fluorescent emission (714 nm) and superparamagnetic iron oxide (SPIO) into a polystyrene-polyethylene glycol (PS-PEG) matrix to form TB/SPIO@PS-PEG nanoparticles (TSP NPs). The as-prepared TSP NPs exhibit red aggregation-induced emission (AIE) with a maximum wavelength at 655 nm and high fluorescence quantum yield (QY) of 14.

A cyanide-sensing detector in aqueous solution based on anion-π interaction-driven electron transfer.

A "turn on" fluorescent and colorimetric sensor, HAT(CN)6, was developed for the light-up detection of cyanide. It was implemented through its strong anion-π interaction, inducing thermal CN- → HAT(CN)6 electron transfer, to give the dianion product [HAT(CN)6]2-, which exhibits unexpected fluorescence. The sensor shows high selectivity, rapid response and a low detection limit towards CN- in aqueous solution, hence indicating its enormous potential in practical applications.

Redox-responsive Fluorescent Nanoparticles Based on Diselenide-containing AIEgens for Cell Imaging and Selective Cancer Therapy.

A fluorescent, diselenide-containing 9,10-distyrylanthracene (DSA) derivative (SeDSA) with aggregation-induced emission (AIE) characteristic was successfully synthesized and SeDSA nanoparticles (NPs) were prepared through a nanoprecipitation method. SeDSA could coassemble with an antitumor prodrug, diselenide-containing paclitaxel (SePTX), which could be obtained by precipitation, to form SeDSA-SePTX Co-NPs (Co-NPs). Molecular dynamics (MD) simulations reveal that the driving forces for the self-assembly behaviors of SeDSA NPs and SePTX NPs are π-π interactions and hydrophobic interactions, respectively, while the driving forces for Co-NPs include hydrophobic interactions between SeDSA and SePTX, π-π interactions between SeDSA molecules and hydrophobic interactions between SePTX molecules.

A novel cascade strategy with supramolecular and chemodosimetric methods for designing a fluorescent ratiometric detector hypersensitive to trace water.

An intensely fluorescent zinc-salicylideneimine complex (-Zn(II)) was developed as a fluorescent ratiometric detector for the quantitative determination of trace water contents both in THF and methanol. It works based on a water-triggered cascade process: the dissociation reaction of the supramolecular ensemble and the subsequent hydrolysis reaction of its ligand.