查看更多>>摘要：Two series of diketobenzofurans (5-acetylbenzofurans substituted by an aroyl group in 4 or 6 positions) have been prepared. The synthetic approach developed here makes it possible to vary the nature of the aromatic subunits (ethylthiophene, anisol, N,N-dimethylaniline) and substituents (butyl, 2-methoxyethoxyethyl, N,N-dibutylaminophenyl) on the furan fractions. The self-condensation of these diketones followed by boron complexation allows us to obtain dibenzofuranBODIPYs. The synthesis strategy used is the same as for the dibenzoBODIPYs. Their linear or banana architectures are due to the structures of the precursor diketones and the spectral properties of the BODIPYs are also modulated by the nature of the substituents. Their optical properties have shown a high quantum efficiency associated with a notorious hyperchromic shift leading to fluorophore with improved brightness in the near infrared region.
Penthala, RajuOh, HyeonPark, Si HyeongLee, In Yeol...
12页
查看更多>>摘要：Two types of novel reactive disperse dyes comprising carbamates (CNU-6A, CNU-6B and CNU-6C) and cyanuric chloride (CNU-8A, CNU-8B and CNU-8C) reactive functional groups were designed and synthesized from the anthraquinone parent body. The structures of these synthesized reactive disperse dyes have been defined by IR, 1H NMR, 13C NMR, HRMS and UV-Vis spectroscopy. Further, the dyeing experiments were performed on polyamide and cotton fabrics in supercritical carbon dioxide conditions with the 0.5% (owf) of dye concentration, at 25 MPa (pressure), and 120 degrees C (temperature) for 1 h. A significant improvement in the color strength and dye fixation efficiency has been observed for the carbamate reactive disperse dyes. This is due to the formation of a covalent bond between the carbamate functional group and the amine (-NH) and hydroxy (-OH) group of the fabrics. Besides, the dyed fabrics displayed favorable fastness (wash, crocking, light and sweat) properties indicating that the synthesized dyes meet the garment dyeing standards.
查看更多>>摘要：Three different molecular designs based on BODIPY dye have been proposed as photosensitizers (PSs) for photodynamic therapy (PDT) by the inclusion of halogen atoms (Iodine) at 2,6-positions and with extended conjugation at 3, 5-positions and varying the substitution at meso position. The synthesis is described and their main photophysical features including singlet oxygen production and triplet states were characterized by absorption and fluorescence spectroscopy (steady-state and time-correlated) and nanosecond transient absorption spectroscopy. The results were compared with the commercial Chlorin e6. The three new red-halogen-BODIPYs showed a great balance between singlet oxygen generation (Phi(Delta)>= 0.40) and fluorescence (Phi(fl)>= 0.22) for potential application on PDT, and particularly in theragnosis. In vitro experiments in HeLa cells were done to study their performance and to elucidate the best potential candidate for PDT.
查看更多>>摘要：Photodynamic therapy, during which nontoxic photosensitizers can be photo-activated to generate cytotoxic reactive oxygen species, has attracted great interest. However, the strong aggregation and poor tumor targeting of photosensitizers, the short action radius and lifetime of reactive oxygen species limit the therapeutic efficiency greatly. Herein, indomethacin, an inhibitor and substrate of cyclooxygenase-2, is introduced to conjugate with zinc phthalocyanines for successively solving these three problems. Own to indomethacin moiety, our designed photosensitizer IMC-Pc can bind to cyclooxygenase-2 with reduced aggregation, and its binding mechanism was demonstrated by fluorescence enhancement and docking calculations. Subsequently, the indomethacin moiety assists ZnPc selectively targeting to cyclooxygenase-2 expressive tumor cells, and further accumulating in Golgi apparatus. Importantly, our results exhibit the improved intracellular reactive oxygen species generation and enhanced anticancer efficacy of IMC-Pc. Overall, such a novel photosensitizer with "three-in-one" cyclooxygenase-2-driven dual targeting and aggregation inhibition is a promising candidate for improving therapeutic efficacy.
查看更多>>摘要：Near-infrared two-photon absorption (TPA) molecules designed based on intramolecular charge-transfer (CT) interactions have been widely investigated during the last few decades; however, studies on supramolecular TPA materials based on intermolecular CT interactions are quite rare. In this work, cocrystals of acridine and 1,2,4,5-tetracyano-benzene were successfully prepared by self-assembly. The cocrystals show yellow emission centered at similar to 540 nm with a solid-state photoluminescence quantum yields (PLOY) of 22.48%. Two-photon excited fluorescence (TPEF) measurements show that the cocrystals display wide-window TPEF that is absent in their individual components. Optical absorption analysis indicate that the fluorescence is originated from excitation from the ground states to CT exciton states instead of exciton states of donor or acceptor molecules. This work may facilitate further two-component nonlinear optical material design and applications.
查看更多>>摘要：A series of variably substituted 3-arylallylidene indolones were synthesized as diastereomeric mixtures applying a novel consecutive three-component Heck-condensation sequence in the sense of a one-pot synthesis. The N-substitution pattern was found to be crucial for the fluorescence in the solid state. Accordingly, the synthetic route was extended to a consecutive four-component reaction to generate a diverse compound library of Boc-substituted 3-arylallylidene indolones. Studying the structure-property relationship by Hammett correlation revealed a discontinuous behavior of the longest wavelength absorption bands of these compounds. 3-Arylallylidene indolones exclusively fluoresce in the solid state. Exceptions are strongly donor-substituted derivatives, which also luminesce in solution and reveal positive emission solvatochromism. With the N-tosyl derivative, an AIE (aggregation induced emission) chromophore was discovered and for the (p-anisyl)2N-substituted derivative aggregation induced emission enhancement (AIEE) was found. The absorption spectra of the 3-arylallylidene indolones can be plausibly rationalized by TD(DFT) calculations. Interestingly, the diastereomers, which can be photoisomerized, are very similar in their photophysical properties.
查看更多>>摘要：The regulation factors of rhodamine spirolactam switch has captured great attention because of its great potential applications in super-resolution image and fluorescent probe fields. Herein, we developed two Hg2+ rhodamine probe bearing flexible alpha-amino acid hydrazines, Rh-SH and Rh-MH, to investigate photo-operated rhodamine switch induced by Hg2+. The Hg2+ binding process with Rh-SH containing serine hydrazines moiety was more sensitive to UV light, owing to weak affinity with Hg2+. On the contrary, UV light had little effect on Hg2+ binding process of Rh-MH bearing methionine hydrazine group. The strong Hg2+ binding affinity of Rh-MH demonstrated a higher sensitivity to Hg2+, and detection limit of Rh-MH was 2.32 x 10(-6) M. Probe Rh-MH can also map the distribution of Hg2+ in mitochondria of MCF-7 cells. The modulation of binding affinity of flexible alpha-amino acid hydrazine with Hg2+ might provide new opportunity and strategy to photo-promoted ring switch of rhodamine spirolactam.
查看更多>>摘要：Recently, the single benzene molecule has attracted widespread attention in room temperature phosphorescence (RTP) materials for its simple structure. However, it is difficult to achieve the long wavelength emission and there are few feasible, universal strategies to construct phosphors with long wavelength emission. In this study, a series of X-shaped phosphors derived from tetrafluoroterephthalonitrile were synthesized and copolymerized with acrylamide to obtain RTP materials. Polymers containing selenium (Se) atoms exhibited long wavelength RTP emission around 600 nm and over 200 nm Stokes shift. PN1, the fluorescence and phosphorescence dual emission material, exhibited red phosphorescence emission at 605 nm. Theoretical calculation was performed to explain the underlying reasons for the produce of phosphorescence.
查看更多>>摘要：Surface defects on CsPbX3 nanocrystals (NCs) commonly lead to the degeneration of photoluminescence emission and stability of CsPbX3 NCs. Defect passivation by surface engineering provides an effective route to improve the optical properties and stability. In this work, a series of aromatic carboxylic acids were explored to modify the assynthesized CsPbBr3 NCs. The surface defects of CsPbBr3 NCs are found to be effectively passivated via the binding of carboxyl group with uncoordinated Pb2+ on the surface of CsPbBr3 NCs. The coordination ability of carboxyl groups with Pb2+ can be regulated by the electron effect generated by different groups at the para-position of carboxyl groups, thereby adjusting the passivation of surface defects. Benefitting from the effective passivation of surface defects, the PL emission and stability of the CsPbBr3 NCs can be effectively enhanced. Among them, the CsPbBr3 NCs modified with the softest 4-(trifluoromethyl)benzoic acid show near-unity photoluminescence quantum yields, a single-exponential photoluminescence decay kinetics and excellent stability.
查看更多>>摘要：Phosgene is a suffocating toxic gas that seriously threatens human health and public security. In this work, we devised a colorimetric and fluorogenic chemosensor (BDY) for phosgene by using 3,5-dimethyl BODIPY as a fluorescent reporter and o-phenylenediamine as the recognition site. The BDY sensor displayed an obvious color change from yellow to pink in conjugation with a fluorescence turn-on response due to nucleophilic substitution and cyclization reactions with phosgene. BDY could detect phosgene with a rapid response (9 s), low detection limit (14 nM), and outstanding selectivity. Moreover, BDY-loaded test strips were prepared to serve as portable and sensitive kits for real-time visual monitoring phosgene with good performance.
NSTL
Elsevier