New Dinuclear Macrocyclic Copper(II) Complexes as Potentially Fluorescent and Magnetic Materials.

Two dinuclear copper(II) complexes with macrocyclic Schiff bases K1 and K2 were prepared by the template reaction of (R)-(+)-1,1'-binaphthalene-2,2'-diamine and 2-hydroxy-5-methyl-1,3-benzenedicarboxaldehyde K1, or 4-tert-butyl-2,6-diformylphenol K2 with copper(II) chloride dihydrate. The compounds were characterized by spectroscopic methods. X-ray crystal structure determination and DFT calculations confirmed their geometry in solution and in the solid phase. Moreover, intermolecular interactions in the crystal structure of K2 were analyzed using 3D Hirshfeld surfaces and the related 2D fingerprint plots. The magnetic study revealed very strong antiferromagnetic CuII-CuII exchange interactions, which were supported by magneto-structural correlation and DFT calculations conducted within a broken symmetry (BS) framework. Complexes K1 and K2 exhibited luminescent properties that may be of great importance in the search for new OLEDs. Both K1 and K2 complexes showed emissions in the range of 392-424 nm in solutions at various polarities. Thin materials of the studied compounds were deposited on Si(111) by the spin-coating method or by thermal vapor deposition and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), and fluorescence spectroscopy. The thermally deposited K1 and K2 materials showed high fluorescence intensity in the range of 318-531 nm for K1/Si and 326-472 nm for the K2/Si material, indicating that they could be used in optical devices.

Experimental and Theoretical Studies of the Optical Properties of the Schiff Bases and Their Materials Obtained from o-Phenylenediamine.

Two macrocyclic Schiff bases derived from o-phenylenediamine and 2-hydroxy-5-methylisophthalaldehyde L1 or 2-hydroxy-5-tert-butyl-1,3-benzenedicarboxaldehyde L2, respectively, were obtained and characterized by X-ray crystallography and spectroscopy (UV-vis, fluorescence and IR). X-ray crystal structure determination and DFT calculations for compounds confirmed their geometry in solution and in the solid phase. Moreover, intermolecular interactions in the crystal structure of L1 and L2 were analyzed using 3D Hirshfeld surfaces and the related 2D fingerprint plots. The 3D Hirschfeld analyses show that the most numerous interactions were found between hydrogen atoms. A considerable number of such interactions are justified by the presence of bulk tert-butyl groups in L2. The luminescence of L1 and L2 in various solvents and in the solid state was studied. In general, the quantum efficiency between 0.14 and 0.70 was noted. The increase in the quantum efficiency with the solvent polarity in the case of L1 was observed (λex = 350 nm). For L2, this trend is similar, except for the chloroform. In the solid state, emission was registered at 552 nm and 561 nm (λex = 350 nm) for L1 and L2, respectively. Thin layers of the studied compounds were deposited on Si(111) by the spin coating method or by thermal vapor deposition and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), spectroscopic ellipsometry and fluorescence spectroscopy. The ellipsometric analysis of thin materials obtained by thermal vapor deposition showed that the band-gap energy was 3.45 ± 0.02 eV (359 ± 2 nm) and 3.29 ± 0.02 eV (377 ± 2 nm) for L1/Si and L2/Si samples, respectively. Furthermore, the materials of the L1/Si and L2/Si exhibited broad emission. This feature can allow for using these compounds in LED diodes.

Dinuclear Copper(II) Complexes with Schiff Bases Derived from 2-Hydroxy-5-Methylisophthalaldehyde and Histamine or 2-(2-Aminoethyl)pyridine and Their Application as Magnetic and Fluorescent Materials in Thin Film Deposition.

Two Cu(II) complexes, 1 and 2, with tridentate Schiff bases derived from 2-hydroxy-5-methylisophthalaldehyde and histamine HL1 or 2-(2-aminoethyl)pyridine HL2, respectively, were obtained and characterized by X-ray crystallography, spectroscopic (UV-vis, fluorescence, IR, and EPR), magnetic, and thermal methods. Despite the fact that the chelate formed by the NNO ligand donors (C26-C25H2-C24H2-N23=C23H-C22-C19Ph(O1)-C2(Ph)-C3H=N3-C4H2-C5H2-C6 fragment) are identical, as well as the synthesis of Cu(II) complexes (Cu:L = 2:1 molar ratio) was performed in the same manner, the structures of the complexes differ significantly. The complex 1, {[Cu2(L1)Cl2]2[CuCl4]}·2MeCN·2H2O, consists of [Cu2(L1)Cl2]+ units in which Cu(II) ions are bridged by the HL1 ligand oxygen and each of these Cu(II) ions is connected with Cu(II) ions of the next dimeric unit via two bridging Cl- ions to form a chain structure. In the dinuclear [Cu2(L2)Cl3]0.5MeCN complex 2, each Cu(II) is asymmetrically bridged by the ligand oxygen and chloride anions, whereas the remaining chloride anions are apically bound to Cu(II) cations. In contrast to the complex 1, the square-pyramidal geometry of the both Cu(II) centers is strongly distorted. The magnetic study revealed that antiferromagnetic interactions in the complex 2 are much stronger than in the complex 1, which was corresponded with magneto-structural examination. Thin layers of the studied Cu(II) complexes were deposited on Si(111) by the spin coating method and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), and fluorescence spectroscopy. The Cu(II) complexes and their thin layers exhibited fluorescence between 489-509 nm and 460-464 nm for the compounds and the layers, respectively. Additionally, DFT calculations were performed to explain the structures and electronic spectral properties of the ligands.

One-day pulsed-field gel electrophoresis protocol for rapid determination of emetic Bacillus cereus isolates.

Bacillus cereus, the Gram-positive and spore-forming ubiquitous bacterium, may cause emesis as the result of food intoxication with cereulide, a heat-stable emetic toxin. Rapid determination of cereulide-positive B. cereus isolates is of highest importance due to consequences of this intoxication for human health and life. Here we present a 1-day pulsed-field gel electrophoresis for emetic B. cereus isolates, which allows rapid and efficient determination of their genomic relatedness and helps determining the source of intoxication in case of outbreaks caused by these bacilli.

[A method of manufacture and characteristic of surface properties and biological activity of thin-film coatings of Cu-Ti system]. / Sposób wytwarzania oraz charakterystyka wlasciwosci powierzchni i aktywnosci biologicznej cienkowarstwowych powlok ukladu typu Cu-Ti.

BACKGROUND: Biomaterials in the form of thin-film coatings as-deposited on different substrates are nowadays increasingly popular. In particular coatings based on a combination of biocompatible materials (eg. titanium) with metals of high biological activity (eg. copper) have a potentially wide range of applications as active films, intended for various types of medical devices. OBJECTIVES: The aim of this study was to present a method for preparation and analysis of the properties of Cu-Ti thin films, in particular their biological activity in connection with the properties of the surface. MATERIAL AND METHODS: The films were prepared by magnetron sputtering method with the aid of an innovative four-target apparatus. During deposition process two metallic targets (copper and titanium) were sputtered under an argon atmosphere. Material composition of produced coatings was characterized by scanning electron microscope equipped with an adapter for energy dispersive spectroscopy. Moreover, the surface microstructure and roughness of coatings was characterized based on three-dimensional surface profiles, which were obtained with the aid of optical profilometer. The research was also carried out by investigations of surface wettability on the apparatus for measurements of contact angle. Characterization of Cu-Ti surface properties was also expanded by microbiological tests involving Staphylococcus aureus (PCM 2602) bacteria and investigations of cytotoxicity with L 929 (NCTC clone 929) cell line. RESULTS: Measurements have shown that the film was composed of 71% at. Cu and 29% at. Ti. The analysis of surface topography has shown that the surface of Cu-Ti thin film was very uniform with roughness in range of nanometers. It was found that as-deposited film is hydrophilic. Obtained results has shown that as-deposited film had a very good bactericidal properties and it was cytotoxic. This effect was associated with the migration of copper ions, which was the most intense at the edge of the sample. CONCLUSIONS: The results presented in this paper testify that manufactured Cu-Ti thin films may find practical application in the industry as a bioactive coating.

[Influence of Cu and Nb additives on specific surface properties and biological activity of transparent TiO2 thin-film coatings]. / Wplyw dodatków Cu i Nb na wlasciwosci powierzchni wlasciwej oraz aktywnosc bakteriobójcza przezroczystych powlok cienkowarstwowych TiO2.

BACKGROUND: Titanium dioxide is widely used as a bacteriostatic and non-toxic material. It is important, therefore, to modify its properties, for greater biological activity. OBJECTIVES: The aim of this study was comparison of the specific surface properties and the biological activity of TiO2 and TiO2 with niobium and copper additives--TiO2:(Nb,Cu) thin films. MATERIALS AND METHODS: TiO2 and TiO2:(Nb,Cu) thin films were prepared by high-energy magnetron sputtering of metallic Ti-Nb-Cu target in oxygen atmosphere. Films that have been deposited on glass substrates were investigated by transmission method and with the aid of optical profiler transparent. Besides, wettability measurements and antibacterial testes with Pseudomonas aeruginosa (PCM2058) were performed. RESULTS: The light transmission characteristics have shown that the film with niobium and copper additives was less transparent than undoped titanium dioxide. Studies of surface geometric structure, performed with the aid of optical profilometer, have shown that coatings were uniform and the surface roughness had several nanometers. The roughness of TiO2:(Nb, Cu) was higher compared to the film of undoped TiO2. The wettability measurements have shown that (Nb, Cu) additives cause a significant reduction in the degree of surface wettability relative to TiO2 and the change of properties from hydrophilic to hydrophobic. The results of the microbiological tests have shown that the TiO2:(Nb, Cu) film had a very good antibacterial properties, while the undoped TiO2 did not exhibit such properties. CONCLUSIONS: The analysis of all results of carried investigations has shown that manufactured TiO2:(Nb,Cu) thin films can be used as a transparent antibacterial coating.

New dinuclear zinc(ii) complexes with Schiff bases obtained from o-phenylenediamine and their application as fluorescent materials in spin coating deposition.

Two Zn(ii) complexes, K1 and K2, obtained from the template reaction of zinc(ii) acetate dihydrate with o-phenylenediamine and 2-hydroxy-5-methylisophthalaldehyde (K1) or 2-hydroxy-5-tert-butyl-1,3-benzenedicarboxaldehyde (K2), respectively, were characterized by X-ray crystallography, spectroscopic (UV-vis, fluorescence and IR), and thermal methods. In the complex [Zn2(MeO)1.4(OH)0.6(L1)]·2H2O K1, there are two binding sites in the macrocyclic ligand and they are occupied by zinc(ii) cations found in slightly distorted square pyramidal environment. The zinc(ii) cations are connected by slightly asymmetric oxo bridges with a Zn1-O14-Zn1[-x, -y + 1, -z + 1] angle of 104.8(2)°. In the dimer [Zn2(CH3COO)2(L2)]·2EtOH K2, there are two crystallographically independent binding sites both occupied by zinc(ii) cations. There is a significant difference between both complexes, since in K1 only one site is independent and the second is occupied due to the application of symmetry rules, and the geometry of both sites is identical. Thin layers of the obtained Zn(ii) complexes were deposited on Si(111) by the spin coating method and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), fluorescence spectroscopy and ellipsometry. In the non-absorbing range, the value of the refractive index exhibits normal dispersion between 1.8 and 2.1 for K1_1-K1_3; and between 2.3 and 2.6 for the K2 series of samples established for long wavelengths (longer than 500 nm). The Zn(ii) complexes and their thin layers exhibited fluorescence between 534-573 nm and 495-572 nm for the compounds and the layers, respectively. The highest quantum yield of fluorescence was achieved for K2 in benzene and in the solid state ϕ = 0.78 and 0.58, respectively. The influence of the solvent polarity on the fluorescence properties of the obtained complexes was studied. Additionally, DFT calculations were performed to explain the structures and electronic spectral properties of the complexes.