Tetraphenylethylene-based Organic Functional Materials:Preparation And Application

When traditional dyes are dispersed in aqueous media or interacted with biomacromolecules, ACQ often takes place, which results in drastically negative effects on efficiencies and sensitivities of biosensors or bioprobes. To overcome this problem, recently, molecules with A1E characteristics are developed and draw much attention, due to their enhanced emission in aggregated form or solid-state. Since Tang’s group reported the AIE features of TPE-based luminophors, TPE-based AIE active materials have already shown practical applications in OLEDs, chem-sensors, and bio-probes, due to its efficient preparation and facile functionalization. Furthermore, TPE molecules exhibit propeller-like, nonplanar conformation, which is different from the contorted spiro-cyclic compounds and the planar π-system molecules. Owing to its efficient preparation, propeller-like structure, and AIE characteristics, tetraphenylethylene is expected to be a novel building block for the construction of porous polymers with unique properties. In this thesis, a series of research on the construction of new materials were carried out, and the applications of new materials were also investigated.1. Two TPE-based glyco-conjugates were prepared through Cu(Ⅰ)-catalyzed "Click" ligation and used for studies of carbohydrate-protein interaction and related biosensing. Significant fluorescence change of water-soluble glyco-conjugates can be observed based on aggregation derived from selective glycosidase-induced hydrolysis in aqueous solution, due to the TPE moiety with AIE feature. We believe the method inspired by this novel concept to investigate carbohydrate-mediated biological interactions shows promising applications in biomacromolecule detections and glycobiology studies.2. TPOPs were synthesized efficiently through Suzuki coupling polycondensation reaction. The obtained materials were characterized by NMR, TGA, XRD, SEM and TEM.3. Surface properties, hydrogen uptake capacities and photo luminescence of TPOPs were studied. According to the obtained nitrogen physisorption isotherms, the BET specific surface area values for these porous materials vary between440and736m2g-1. Gravimetric hydrogen adsorption isotherms show that the adsorption capacity for hydrogen is up to1.00wt%(TPOP-3) at1.13bar and77K. Incorporation of tetraphenylethylene moieties into these polymers can induce high photoluminescence (λmax:530-560nm) in solid state.2,4,6-trinitrophenol (picric acid, PA) can cause a significant fluorescence quenching of TPOPs, due to the electron transfer from TPOPs to PA. We believe that tetraphenylcthylene-based porous organic polymers can be used for explosive sensing.