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A fluorophilic fluorescent probe based on a perfluoroalkyl‐substituted bis(binaphthyl) compound was designed and synthesized. It displayed a highly enantioselective fluorescence response toward structurally diverse amino acids in a biphasic fluorous/aqueous system with enantiomeric fluorescent enhancement ratio (ef; ΔID/ΔIL) values up to 45.2 (histidine). It can be used to determine the enantiomeric compositions of amino acids and also allows the amino acid enantiomers to be visually discriminated. NMR and mass‐spectroscopic investigations provided insights into the observed high enantioselectivity. This biphasic fluorescent recognition was used to determine the enantiomeric composition of the crude phenylalanine products generated by an enzyme‐catalyzed asymmetric hydrolysis under various reaction conditions. The fluorous‐phase‐based fluorescence measurement under the biphasic conditions was able to minimize the interference of other reaction components and thus has potential in asymmetric reaction screening. [ABSTRACT FROM AUTHOR]

Samarium and nitrogen co-doped Bi2WO6 nanosheets were successfully synthesized by using a hydrothermal method. The crystal structures, morphology, elemental compositions, and optical properties of the prepared samples were investigated. The incorporation of samarium and nitrogen ions into Bi2WO6 was proved by X-ray diffraction, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. UV/Vis diffuse reflectance spectroscopy indicated that the samarium and nitrogen co-doped Bi2WO6 possessed strong visible-light absorption. Remarkably, the samarium and nitrogen co-doped Bi2WO6 exhibited higher photocatalytic activity than single-doped and pure Bi2WO6 under visible-light irradiation. Radical trapping experiments indicated that holes (h+) and superoxide radicals ( .O2−) were the main active species. The results of photoluminescence spectroscopy and photocurrent measurements demonstrated that the recombination rate of the photogenerated electrons and holes pairs was greatly depressed. The enhanced activity was attributed to the synergistic effect of the in-built Sm3+/Sm2+ redox pair centers and the N-doped level. The mechanism of the excellent photocatalytic activity of Sm-N-Bi2WO6 is also discussed. [ABSTRACT FROM AUTHOR]

A new strategy for fast fluorescent detection of cysteine (Cys), based on a response-assisted electrostatic attraction, is demonstrated. By utilizing this strategy, we designed and synthesized three fluorescent probes for the specific detection of Cys under actual physiological conditions. The probe m- CP, a coumarin fluorophore conjugated with a substituted methyl pyridinium group through an unsaturated ketone unit, showed highly selective and sensitive detection for cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). The kinetic analysis indicated that the sensing process was highly accelerated (a response time less than 1 min) by the response-assisted electrostatic attraction. More importantly, control experiments with isomeric probes first demonstrated that the spatial charge configuration of the probe played an important role in Cys-preferred selectivity and kinetic rate acceleration. Furthermore, the practical utility of the probe m- CP in the fluorescent labeling of Cys residues within proteins was demonstrated. Finally, these probes were employed in living cell imaging with HeLa cells, in which it displayed satisfactory cell permeability and enabled us to distinguish active thiols in the cytoplasm, nucleus, and mitochondria. [ABSTRACT FROM AUTHOR]