Publications by authors named "Fangyuan Gai"

This work demonstrated the design and synthesis of multiple dye-doped silica cross-linked micellar nanoparticles (MD-SCMNPs) by encapsulating three organic dyes (fluorescein derivative (FCD), coumarin derivative (HCE) and Rhodamine b (RhB)) in SCMNPs cores for colour-tuneable sensing of cysteine (Cys) in aqueous media and in living cells. In the presence of Cys, HCE exhibited blue emission, and RhB exhibited purple emission, while FCD reacted with Cys and exhibited green fluorescence "turn-on" in the core of MD-SCMNPs. This green-light-emitting sensing product may cause "step by step" fluorescent resonance energy transfer (FRET) from HCE to the sensing product and then to RhB.

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This work demonstrated the synthesis and design of ultra-bright and ultra-small fluorescent nanoparticles, which were prepared by encapsulating 4-(diphenylamino)benzaldehyde (DPB) in silica cross-linked micellar nanoparticles (SCMNPs). The DPB-doped SCMNPs (DPB-SCMNPs) exhibited ultra-bright fluorescence in an aqueous medium that was 22 times brighter than that of free DPB molecules in an organic solvent. For the first time, density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were used to confirm that the enhanced brightness of the DPB-SCMNPs was due to a hydrogen bond-induced mechanism.

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This work demonstrated the synthesis of (4E)-4-(4-(diphenylamino)benzylideneamino)-1,2-dihydro-1,5- dimethyl-2-phenylpyrazol-3-one (DBDDP) for Fe (III) detection in aqueous media and in the core of silica cross-linked micellar nanoparticles in living cells. The free DBDDP performed fluorescence enhancement due to Fe (III)-promoted hydrolysis in a mixed aqueous solution, while the DBDDP-doped silica cross-linked micellar nanoparticles (DBDDP-SCMNPs) performed an electron-transfer based fluorescence quenching of Fe (III) in living cells. The quenching fluorescence of DBDDP-SCMNPs and the concentration of Fe (III) exhibited a linear correlation, which was in accordance with the Stern-Volmer equation.

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This work demonstrates a novel method for the synthesis of large pore mesoporous silica nanoparticles (MSNs) with a pore diameter of 10.3 nm and a particle diameter of ∼50 nm based on the incorporation of mixed anionic surfactants sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl sulphate (SDS) as the template in the synthesis process. The dispersity, morphology, pore structure and size of mesoporous nanoparticles were adjusted by changing the molar ratio of two anionic surfactants, the concentration of the co-structure-directing agent (3-aminopropyltrimethoxysilane) and the reaction temperature.

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Plasmonic materials with large chiroptical activity at visible wavelength have attracted considerable attention due to their potential applications in metamaterials. Here we demonstrate a novel guest-host chiral nematic liquid crystal film composed of bulk self-co-assembly of the dispersed plasmonic silver nanowires (AgNWs) and cellulose nanocrystals (CNCs). The AgNWs-CNCs composite films show strong plasmonic optical activities, that are dependent on the chiral photonic properties of the CNCs host medium and orientation of the guest AgNWs.

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This work demonstrates a luminescent chemosensor based on silica cross-linked micellar nanoparticles (SCMNPs) designed by encapsulating a phenothiazine-derived Schiff base, (4E)-4-((10-dodecyl-10H-phenothiazin-7-yl)methyleneamino)-1,2-dihydro-1,5-dimethyl-2-phenylpyrazol-3-one (EDDP), for the selective detection of Fe. The encapsulation of EDDP inside SCMNPs (EDDP-SCMNPs) can avoid the metal (Fe/Fe)-promoted hydrolysis of EDDP and, thus, exhibit highly selective determination of Fe. The electron transfer (ET) from EDDP in the core to Fe adsorbed on the shell of EDDP-SCMNPs was verified using UV-vis absorption, fluorescent emission and 3D fluorescence spectra.

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This work demonstrated that water-soluble fluorescent hybrid materials can be successfully synthesized by use of silica cross-linked micellar nanoparticles (SCMNPs) as scaffolds to encapsulate fluorescent conjugated dyes for pH sensing, porphyrin sensing and tunable colour emission. Three dyes were separately encapsulated inside SCMNPs (short to dye-SCMNPs). Each of the dye-SCMNPs indicated longer lifetime in water than that of free dye dissolved in organic solvent.

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Metal-organic polyhedra (MOP) nanocages were successfully surface functionalized via ionic self-assembly and the ordered honeycomb architecture of the encapsulated MOP nanocages was also fabricated at the air/water surface. The results provide a novel synthetic method and membrane processing technique of amphiphilic MOP nanocages for various applications.

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The first rigid dendritic gel with strong emission based on oligocarbazole was reported. It is interesting that the second generation of dendron exhibited gelation ability under ultrasound, and two-component gel could be formed from the first generation of dendron assisted by 1,6-diaminohexane.

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