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A facile strategy was used to construct a series of composite materials with color-tunable and white light emission by encapsulating 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) into framework material [Eu(MCTCA)1.5(H2O)2]·1.75H2O (Eu-MCTCA), which is synthesized based on Eu(NO3)3·6H2O and 5-methyl-1-(4-carboxylphenyl)-1H-1,2,3-triazole-4-carboxylic acid (H2MCTCA). A slight adjustment of the emission color can be easily fulfilled by simply altering the concentration of H4TBAPy or regulating the excitation wavelength. Notably, white light emitting Eu-MCTCA@H4TBAPy can be realized by encapsulating H4TBAPy with a concentration of 0.75 mM, when the excitation wavelength is 350 nm. Furthermore, based on the favorable luminescence and stable structure of Eu-MCTCA@H4TBAPy in water or organic solvents, Eu-MCTCA@H4TBAPy can be used as a potential luminescent probe for detecting Fe3+, Cr2O72− and colchicine. [ABSTRACT FROM AUTHOR]

Vanadium(iii) complexes [V(2,6-pdc)2(H2O)2]·2H2O (1) and V(2,6-pdc)(htba)(H2O)2 (2), (2,6-pdc = 2,6-pyridinedicarboxylic acid, htba = 2-acetoxy-4-trifluoromethylbenzoic acid) have been synthesized by the reaction of V2(SO4)3 with 2,6-pdc (for 1) or 2,6-pdc and htba (for 2) under hydrothermal conditions at 120 °C for 36 hours. Because the vanadium(iii) was easily oxidized into higher oxidation states, we included the reducing agent vitamin C to protect the vanadium(iii) center. The complexes were characterized by elemental analysis, IR and UV-vis spectroscopy, and single-crystal X-ray diffraction. Structural analysis revealed that the central metal V atoms in the complexes 1 and 2 were seven-coordinate, forming pentagonal bipyramid geometries. The complexes catalyzed the bromination of the organic substrate phenol red in the presence of H2O2, bromide and buffer. Compared with vanadium complexes having other oxidation states, the vanadium(iii) complexes had better catalytic activity (the maximum reaction rate constant was 2.424 × 102k(mol L−1)−2 s−1). The mimicking vanadium haloperoxidases also overcame some serious disadvantages of natural enzymes. Therefore, the reaction system described herein can be considered as an effective model for hydrogen peroxide determination. [ABSTRACT FROM AUTHOR]

Four novel supramolecular complexes [Cd(H2L)2]·(NO3)2·2H2O (1), [Cd(H2L)2]·(OH)2·(EtOH)0.5 (2), [Zn(H2L)(2,6-pdc)]·(2,6-H2pdc)1.5·MeOH·0.5H2O (3) and [Zn(H2L)2][Zn(2,5-Hpdc)3]2·1.5H2O (4) (H2L = 2,6-di-(5-methyl-1H-pyrazol-3-yl)pyridine, 2,6-H2pdc = 2,6-pyridinedicarboxylic acid, 2,5-H2pdc = 2,5-pyridinedicarboxylic acid) based on pyrazolyl derivatives as ligands were designed and synthesized. They were characterized by elemental analysis, IR and UV-vis spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction. The structural analysis indicates that the central metal atom (cadmium and zinc atoms) is six-coordinated, and possesses a slightly distorted-octahedral configuration. In addition, a cytotoxicity study was performed using multiple parallel perfused microbioreactors and the potential apoptotic effects on adrenal pheochromocytoma cells and human adipose tissue-derived stem cells were examined by flow-cytometric analysis. The results show that the percentage of apoptotic cells becomes gradually higher as the concentration of the supramolecular complex is increased. [ABSTRACT FROM AUTHOR]