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Two nickel metal-organic frameworks (Ni-MOFs) based on a nitrogen-containing rigid tetracarboxylic acid ligand had been synthesized by the hydrothermal method, namely {[Ni(H4L1)0.5(4,4′-bibp) (H2O)]·1.5H2O}n (1) and {[Ni(H4L1)(H2O)2]·H2O}n (2) (H4L1 = 5,5′-(1H-1,2,4-triazole-3,5-diyl)diisophthalic acid, 4,4′-bibp = 4,4′-di (1H-imidazol-1-yl)-1,1′-biphenyl). Crystal structure analysis revealed that the two complexes exhibited varied structures in the presence or absence of the auxiliary N-donor ligand 4,4′-bibp: the complex 1 was a three-dimensional (3D) metal-organic framework with a (1,2,4,5)-connected {4.64.8}2{42.64}3{6}2 topology. In the complex 2, the carboxylate ligand was used as a junction point to form a 2D layered structure with Ni(II). The results showed that the addition of the 4,4′-bibp has a very important effect on the structure of the complexes. Some conventional characterizations were carried out, such as: Infrared (IR) spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric (TGA) analyses. Moreover, the ORCA program was used to perform density functional theory (DFT) calculations to investigate the molecular properties of the two complexes. [ABSTRACT FROM AUTHOR]

The bioinformatics method is used to analyze the relationship of serum albumin among different species, and to analyze the characteristics of the amino acid changes in the other closely related species of the interaction sites of hypoglycemic drugs miglitol and voglibose with human serum albumin. The results show that the binding sites of miglitol, voglibose and human serum albumin are located at the hydrophobic cavity of human serum albumin subdomain IB, and the main forces are hydrogen bonding and hydrophobic interaction. The amino acids at the binding sites of miglitol and voglibose with human serum albumin are mostly conserved in other species, with only a few amino acids being different and polarities being different. The serum albumin hydrophobicity analysis suggests that the amino acids at the binding sites of miglitol and voglibose with serum albumin are more hydrophilic, less hydrophobic, and the other four species in the same species also have the same phenomenon. These bioinformatics based analysis provide an important scientific basis for the further research on the expression and interaction of hypoglycemic drugs in other species. [ABSTRACT FROM AUTHOR]

Recently, curcumol is one of the important new anti-tumor traditional Chinese medicine monomer. It can help us to better understand the mechanism of drug's action by analyzing the interaction between curcumol and transporter-serum albumin. In this paper, we analyzed the molecular interaction between curcumol and human serum albumin, as well as the characteristics in other closely related species by using multiple sequence analysis, evolutionary relationship and molecular docking technique. The results showed that the active sites II and III between curcumol and human serum albumins are surrounded by hydrophobic amino acids, which suggested that intermolecular hydrophobic interaction plays a very important role. Their lowest binding energies are -7.22 kcal/mol and -8.34 kcal/mol, respectively. Most of the amino acids in the active sites are conservative in other close genetic species, such as Canis lupus, Ovine, Bos mutus and Bos Taurus. It is noticed that few changes occurred between the amino acids with identical polarity. The conformation of the hydroxyl group in curcumol has the most obvious variation in the active site compared with the optimal structure. [ABSTRACT FROM AUTHOR]

The biotoxicity of nanomaterials is very important for the application of nanomaterials in biomedical systems. In this study, proteins with varying secondary structures (α-helices, β-sheets, and mixed α/β structures) were employed to investigate the biological properties of three representative two-dimensional (2D) nanomaterials; these nanomaterials consisted of black phosphorus (BP), graphene (GR), and nitrogenized graphene (C 2 N) and were studied using molecular dynamics simulations. The results showed that the α-helix motif underwent a slight structural change on the BP surface and little structural change on the C 2 N surface. In contrast, the structure of the β-sheet motif remained fairly intact on both the BP and C 2 N surfaces. The α-helix and β-sheet motifs were able to freely migrate on the BP surface, but they were anchored to the C 2 N surface. In contrast to BP and C 2 N, GR severely disrupted the structures of the α-helix and β-sheet motifs. BBA protein with mixed α/β structures adsorbed on the BP and C 2 N surfaces and exhibited biological behaviors that were consistent with those of the α-helix and β-sheet motifs. In summary, C 2 N may possess better biocompatibility than BP and GR and is expected to have applications in the biomedical field. This study not only comprehensively evaluated the biological characteristics of nanomaterials but also provided a theoretical strategy to explore and distinguish the surface characteristics of nanomaterials.

Full-color lanthanide (Ln) photoluminescent materials have attracted considerable interest owing to their potential applications in display systems and lighting technologies. Herein, full-color photoluminescent films have been designed and fabricated facilely with a fixed-component Ln-based (Ln=Tb and Eu) polymer hybrid doped with a proton-sensitive amide-type β-diketonated photosensitizer, N-(2-pyridinyl)benzoylacetamide (HPBA). The tunable photoluminescence emissions of the films are achieved by changing the amounts of OH(-) in the hybrid rather than varying the relative concentrations of the lanthanide ions and photosensitizers, thus representing a new paradigm for full-color displays. The emission color can also be finely tuned through the variation of the excitation wavelength, and white-light emission can be achieved when the given film is excited at the visible region (405 nm). The photophysical properties and the mechanisms of the intra- and intermolecular energy transfer before and after deprotonation have been investigated in detail. Meanwhile, the films might find application as vapoluminescent sensors due to their good stability, sensitivity, reversibility, and quick response when triggered by a base-acid vapor., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)