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Au-Beta zeolites prepared by different methods and on supports of different compositions were studied in base-free glucose oxidation to gluconic acid. The catalysts were characterized by XRD, N2 adsorption/desorption, TEM, UV–vis and FTIR spectroscopy, ICP-OES and pyridine adsorption combined with FTIR measurements in order to estimate the structural/textural and surface properties of prepared materials and their impact on the activity and selectivity in glucose oxidation. A relationship between the gold particle size, depending on the method of gold deposition, and the effectiveness of glucose oxidation to gluconic acid, expressed by glucose conversion and the selectivity to gluconic acid, was observed. The optimal average gold nanoparticles (NPs) size corresponding to the maximum glucose conversion was ∼6 nm, whereas the normalization of structure/size sensitivity to exposed surface gold atoms (TOF) moved this optimum to Au NPs of ca. 24 nm. The presence of niobium in the support reduced the gold particle size, decreased the activity in glucose oxidation and affected the selectivity of the reaction, enhancing glucuronic acid formation. Addition of cerium dopant to the zeolite support for gold resulted in an increase in glucose conversion and stabilization of the catalyst activity for six investigated reaction cycles. Deactivation of the catalysts in successive reaction runs depended on the method of gold deposition and the type of zeolite support.

The quantitation and qualification of amino acids are most commonly used in clinical and epidemiological studies, and provide an excellent way of monitoring compounds in human fluids which have not been monitored previously, to prevent some diseases. Because of this, it is not surprising that scientific interest in evaluating these compounds has resurfaced in recent years and has precipitated the development of a multitude of new analytical techniques. This review considers recent developments in HPLC analytics on the basis of publications from the last few years. It helps to update and systematize knowledge in this area. Particular attention is paid to the progress of analytical methods, pointing out the advantages and drawbacks of the various techniques used for the preparation, separation and determination of amino acids. Depending on the type of sample, the preparation conditions for HPLC analysis change. For this reason, the review has focused on three types of samples, namely urine, blood and cerebrospinal fluid. Despite time-consuming sample preparation before HPLC analysis, an additional derivatization technique should be used, depending on the detection technique used. There are proposals for columns that are specially modified for amino acid separation without derivatization, but the limit of detection of the substance is less beneficial. In view of the fact that amino acid analyses have been performed for years and new solutions may generate increased costs, it may turn out that older proposals are much more advantageous.

We report on the polymorphism in helical nanofilament (HNF, B 4 ) liquid crystal (LC) phase depending on the fabrication methods, here UV light-driven formation and templated assisted self-assembly in the nanoconfined geometries. As a result, uniaxially oriented HNFs with different helical structures are obtained, in which the polymorphs, twisted ribbon, and cylindrical ribbon are generated to show even molecular lattice has a different orientation. The detailed structures are directly observed using scanning electron microscopy and grazing incidence X-ray diffraction with synchrotron radiation. Our resultant polymorph would be used in the chiro-optical applications due to the capability of fine control of the helical structures.

Within the present study, novel chelating resins containing a layer loaded with N-methyl-D-glucamine functionalities were synthesized. The procedure involved impregnation of macroporous Amberlite XAD-4 adsorbent using mixture of vinylbenzyl chloride (VBC) and divinylbenzene (DVB) further subjected to free radical suspension polymerization. The so-obtained 1PTN and 2PTN adsorbents were characterized by expanded-gel or microporous structure of VBC-co-DVB layer, respectively. The both materials were used in desalination of geothermal water aimed to decrease levels of boron and arsenic. As a part of this, he research on boron and arsenic removal included batch adsorption and kinetic studies. The results have shown that the resin 1PTN showed maximum boron removal of 64% and arsenic removal of 18% from the geothermal water. The resin 2PTN exhibited competitive boron removal performance as compared to the commercial Diaion CRB 05 resin, reaching its efficiency by removing over 96% of boron. Also, the sample 2PTN outmatched Diaion CRB 05, removing 97% of arsenic and leading to decrease of its concentration to permissible level., bilateral collaboration program between Turkey and Poland [TUBITAK-NCBR-2549, TuBTAK 117M023]; Turkish Higher Education CouncilMinistry of National Education - Turkey [YoK 100-2000], This research has been financially supported by bilateral collaboration program (TUBITAK-NCBR-2549) between Turkey and Poland (Project No: TuBTAK 117M023).; E. Altok is grateful for the PhD scholarship of Turkish Higher Education Council (YoK 100-2000). We thank Izmir Geothermal Co. for the kind support to get geothermal water samples. We also acknowledge Mitsubishi Chem. Japan for Diaion CRB 05 resin.

We report on the synthesis of composite nanobeads with antibacterial properties. The particles consist of polystyrene cores that are surrounded by sulfonic gel shells with embedded silver nanoparticles. The nanocomposite beads are prepared by sulfonation of polystyrene particles followed by accumulation of silver ions in the shell layer and subsequent reduction with sodium borohydride. The resulting material has been characterized by electron microscopy, vibrational and X-ray photoelectron spectroscopy and several other experimental techniques. It was shown that sodium borohydride reduces silver ions embedded in the gel layer producing silver nanoparticles but also transforms a fraction of sulfonic groups in the polymer to moieties with sulfur in a lower oxidation state, likely thiols. It is hypothesized that the generated thiol groups are anchoring the nanoparticles in the gel shell of the nanobeads stabilizing the whole structure. The silver-decorated nanobeads appear to be a promising material with considerable antimicrobial activity and were tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis. The determined minimum inhibitory (MIC) and minimum biofilm inhibitory (MBIC) concentrations are comparable to those of non-incorporated silver nanoparticles.

Invited for the cover of this issue are the groups of Janusz Lewiński from Polish Academy of Sciences and Warsaw University of Technology. The image depicts how a zinc ethylsulfinate web can be woven by using diethylzinc and sulfur dioxide. Read the full text of the article at 10.1002/chem.201902733.

The purpose of our research was to obtain and characterize Cu(II), Co(II) and Ni(II) complexes with herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA). The structural characterization of compounds in their powder form was based on various laboratory as well as synchrotron X-ray spectroscopic methods, magnetic measurements and atomistic calculations. The anhydrous [Cu(MCPA)2]n complex exhibits a distorted square-planar geometry. [Co(MCPA)2(H2O)4]·H2O and [Ni(MCPA)2(H2O)4]·H2O complexes have octahedral molecular geometry with two MCPA anions acting as monodentate ligands. The X-ray crystal structure analysis performed for Cu(II) complex after its recrystallization from N,N-dimethylformamide solution showed the formation of dinuclear complex with solvent molecules included in the coordination sphere of Cu(II). MCPA herbicide and its Cu(II), Co(II) and Ni(II) complexes showed the low cytotoxicity potential against HaCaT and V79 cells with IC50 in the range from 65 to >100 µM.

Hypothesis A new, facile in-situ method for synthesis of polymeric nanocomposites (NCs) with nanoparticles (NPs) of Au, Pt and Pd is proposed. The method involves reduction-coupled sorption of Au(III), Pt(VI), and Pd(II), which avoids diffusion limitations, allowing the precipitation and stabilization of the NPs directly in the polymeric matrix. Experiments The obtained nanomaterials were characterized by transmission electron microscopy (TEM), and Fourier-transformation infrared spectroscopy (FT-IR). NPs loaded into polymers were also investigated using X-ray diffraction (XRD). Findings Based on the results, it was concluded that the amino functionalities simultaneously reduced noble metals ions and capped the NPs. The average diameter of the obtained AuNPs ranged from 25 to 109 nm, while reduction-coupled sorption was carried out in 1 and 3 mol L−1 HCl solutions, respectively. Applying a 0.1 mol L−1 HCl solution containing Au(III), Pd(II) and Pt(VI), a NC with AuNPs and cubic-like PdNPs was fabricated, while using a solution of the same composition, but in 3 mol L−1 HCl, resulted in formation of a NC with flower-like PtNPs. Ultimately, the selected NC based on a resin with functionalities derived from 1-(2-aminoethyl)piperazine and with bi-metallic active sites, i.e. AuNPs and PdNPs, revealed catalytic activity in the reduction of 4-nitrophenol.

International audience

Enterococcus faecalis is known as a significant nosocomial pathogen due to its natural resistance to many antibacterial drugs. Moreover, it was found that E. faecalis infection causes inflammation, production of reactive oxygen species, and DNA damage to human gastric cancer cells, which can induce cancer. In this study, we synthesized and tested the biological activity of a new Schiff base, 5-[(4-ethoxyphenyl)imino]methyl-N-(4-fluorophenyl)-6-methyl-2-phenylpyrimidin-4-amine (3), and compared its properties with an analogous amine (2). In the biological investigation, (3) was found to have antibacterial activity against E. faecalis 29212 and far better anticancer properties, especially against gastric adenocarcinoma (human Caucasian gastric adenocarcinoma), than (2). In addition, both derivatives were non-toxic to normal cells. It is worth mentioning that (3) could potentially inhibit cancer cell growth by inducing cell apoptosis. The results suggest that the presence of the –C=N– bond in the molecule of (3) increases its activity, indicating that 5-iminomethylpyrimidine could be a potent core for further drug discovery research.

The experimental and theoretical studies of the local atomic order and chemical binding in tantalum oxide amorphous films are presented. The experimental studies were performed on thin films deposited at the temperature of 100 °C by atomic layer deposition on silicon (100) and glass substrates. Thin films of amorphous tantalum oxide are known to exhibit an extremely large extent of oxygen nonstoichiometry. Performed X-ray absorption and photoelectron studies indicated the oxygen over-stoichiometric composition in the considered films. Surplus oxygen atoms have 1s electron level with binding energy about 1 eV higher than these in reference Ta2O5 oxide. The density functional theory was applied to find the possible location of additional oxygen atoms. Performed calculation indicated that additional atoms may form the dumbbell defects, which accumulate the dangling oxygen bonds in orthorhombic structure and lead to increase of oxygen 1s level binding energy. The presence of this kind of oxygen–oxygen bonding may be responsible for increase of amorphous film chemical resistivity which is very important in many applications.

Zinc oxide nanoparticles were synthesized with microwave hydrothermal technique and tested as luminescent contrast for biological imaging. Luminescence was activated by Eu3+ ions embedded in the nanoparticle matrix in the increasing concentrations of 1, 5 and 10 %mol. It was found that europium did not create a separate crystalline phase up to the concentration as high as 5 %mol. However, Eu3+ ions did not substitute Zn2+ in the host lattice, but allocated in the low symmetry environment. It was proposed that europium was locating in the inter-grain space or on the surface of nanoparticles. The luminescence intensity in ZnO:Eu, as well as the size of particles, increased with the Eu ion concentration. Moreover, in 10 %mol Eu sample, the separate phase of Eu-hydroxide was identified with crystals of micrometre length. Interestingly, in vivo study revealed, that contrary to the in silico experiments, following gastric gavage, the brightest nanoparticle-related luminescence signal was observed at 1 %mol. concentration of Eu. Since the alimentary uptake of nanoparticles was related to their size, we concluded that the increase in luminescence at 5 and 10 %mol. Eu concentrations was associated with the largest ZnO:Eu and Eu-hydroxide particles that did not cross the gastrointestinal barrier.

Elemental sulfur (ES) is a component essential for proper development of animals, but it can be toxic for aquatic organisms. The objectives of the study reported here included determination of ES concentrations in sediment collected in the area of the Gulf of Gdansk (Baltic Sea) and search for the possible correlations with the ecotoxicity results. Sediment samples were collected from four locations: the Vistula River mouth, in the Port Basin, in the area of discharge of the treated wastewater from the Wastewater Treatment Plant (WWTP) and in the area of the sunken World War II s/s ‘Stuttgart’ shipwreck. The levels of elemental sulfur were determined using a gas chromatograph coupled with a mass spectrometer (GC–MS). Toxicity of marine sediment samples was estimated for three biotest organisms – bioluminescent bacteria Vibrio fischeri, crustacean Heterocypris incongruens, and Synapis alba plant. The highest toxicity of sediments for all indicator organisms was observed in samples taken at the place of the shipwreck (2–100%). The same samples had a high sulfur content (16.7–143.2 µg/g dry weight (d.w.)) therefore, it was decided to investigate whether the presence of ES in the sediment in the studied area can have an impact on the results of the ecotoxicity determination in real samples. However, the removal of sulfur from the samples resulted in no significant changes in the level of toxicity of the samples. In this research it could not be confirmed that the presence of elemental sulfur is the only factor responsible for the observed sediment toxicity. It seems that other compounds or their mixtures present in the sediment may have a significant influence on the results obtained.

The molecular structure of Cu(II) complexes, obtained using direct and electrochemical synthesis, with 4-oxo-4H-chromene-2-carboxylic acid, 2-oxo-2H-chromene-3-carboxylic acid and (7-hydroxy-2-oxo-2H-chromen-4-yl)acetic acid have been studied. Due to difficulties in obtaining complexes as monocrystals the combination of laboratory based methods with X-ray absorption spectroscopy supported with density functional theory calculations has been employed. Complexes were found to be mono- and dinuclear. Different coordination modes were also observed: monodentate, bidentate chelating and carboxylate bridges. The octahedral geometry was found for complex with 2-carboxylic acid whereas for the other two the tetragonal pyramid was formed around copper cations.

Summary Introduction: Due to its low cost and easy availability on the market, the petitgrain oil is commonly used in food, cosmetics, and aromatherapy. Objective: The examination of chemical composition and antibacterial activity of commercial petitgrain oil. Methods: Identification of chemical components of the petitgrain oil was performed by gas chromatography (GC). The minimum inhibitory concentrations (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC) were determined using macrodilution method for the reference strains of bacteria and fungi. Results: Twenty components were identified. The petitgrain oil contained mostly oxygenated monoterpene hydrocarbons (98.01%), and the main components included linalyl acetate (48.06%) and linalool (26.88%). The MIC/MBC of the petitgrain oil for bacteria was in the range of 0.63-5.0/1.25-5.0 mg/ml and for fungi in the range of 1.25-40/5.0-80 mg/ml. Conclusion: The petitgrain oil had higher antibacterial activity than antifungal activity. Bacillus subtilis among the tested bacteria and Aspergillus niger and Penicillium expansum among the fungi were found to be highly inhibited by the petitgrain oil.

Four Cu(II) complexes with 2- and 3-benzo[ b ]furancarboxylic acids have been synthesized and characterized using combination of two spectroscopic techniques. These techniques were: ( i ) FTIR and ( ii ) XAFS. FTIR analysis confirmed that complexes were formed and gave insight into identification of possible coordinating groups to the metallic center. XANES analysis indicated that the oxidation state of Cu is +2. EXAFS analysis allowed to identify that the first coordination sphere is formed by 4–5 oxygen atoms with the Cu–O distances around 2 A. Combining these techniques it was possible to structurally describe novel Cu(II) complexes with benzo[ b ]furancarboxylic acids.

The new Cu(II) complexes of 1/2/3-(bromophenyl)-3-(1,7,8,9-tetramethyl-3,5-dioxo-4-azatricyclo[5.2.1.0 2,6 ]dec-8-en-4-yl)thiourea derivatives have been synthesized. The spectroscopic studies together with density functional theory calculations of Cu(II) complexes revealed that two parent ligands coordinate to the copper cation in bidentate fashion via thiocarbonyl S and deprotonated N atoms forming rarely observed four-membered chelate ring, with nearly planar [CuN 2 S 2 ] moiety. In solid state, the mononuclear complex is formed for thiourea derivative with 3-bromophenyl, whereas for Cu(II) connection with 2- and 4-bromophenyl-thioureas the formation of dinuclear complexes is observed, the latter formed by the stacking of mononuclear complexes. The microbiological activity of novel compounds has been evaluated. The Cu(II) complex with 4-bromophenyl ring connected to the thiourea moiety showed significant inhibition against standard strains of S. aureus and S. epidermidis . The range of minimal inhibitory concentration values is 2–4 μg/mL. That compound exhibited antibiofilm potency and effectively inhibited the formation of biofilm of methicillin-susceptive strain of S. epidermidis ATCC 12228. Moreover, the cytotoxicity against the MT-4 cells of all obtained complexes has been evaluated. The complexes turned out to be non-cytotoxic for exponentially growing MT-4.

We have synthesized a series of bromo derivatives of 5-hydroxycoumarin and two new Cu(II) complexes with 6-acetyl-8-bromo-5-hydroxy-4,7-dimethylcoumarin (L2) and 6-acetyl-3,8-dibromo-5-hydroxy-4,7-dimethylcoumarin (L3) ligands, designed as potential active compounds against human cancer cell lines. The elemental analysis, mass spectroscopy, NMR and infrared spectroscopy have been used for basic characterization of analyzed compounds. The X-ray crystal structure analysis for one representative organic compound, 3,6,8-tribromo-5-hydroxy-4,7-dimethylcoumarin (c) has been performed. It has shown that coumarin system is nearly planar and the Br⋯Br interaction is a very characteristic feature of the molecular association for organic ligands. The complexes, Cu(L2)2·3H2O and Cu(L3)(ClO4)·2.5H2O, have been found as four-coordinated and contain copper in the +2 oxidation state according to X-ray absorption spectroscopy. All the compounds have been screened in vitro for their cytotoxic activity against mouse fibroblast and human prostate cancer cells. The coordination products of brominated ligands have shown to be more active than the free ligands and demonstrate significant in-vitro cytotoxicity against human prostate cancer cells (DU145).

We report the synthesis of new Co(II), Ni(II) and Cu(II) complexes with 4-bromophenoxyacetic acid. We characterize these compounds structurally using various laboratory (XRF, IR, UV–vis) and synchrotron (EXAFS, XANES) spectroscopic methods, magnetic measurements and DFT calculations. We found that in the powder form of complexes Co(II) and Ni(II) cations are coordinated by two monodentate carboxylate ligands and the first coordination sphere is completed by water molecules that form an octahedron. The coordination polyhedron of Cu(II) exhibits a distorted tetragonal–pyramidal geometry with two ligands coordinating in bidentate and monodentate fashion via carboxylate O atoms and two water molecules. The X-ray single crystal structure analysis performed for Cu(II) complex after its recrystallization from N,N-dimethylformamide (DMF) solution revealed the formation of dinuclear complex. In crystals, the carboxylate O atoms occupy the bases of two tetragonal pyramids formed around two Cu(II) ions with the DMF molecules in the apical positions.

A method of processing Wasted Electric and Electronic Equipment (WEEE), and the separation of gold that it contains, is presented within the present work. Due to the fact that the amount of Au in real-life secondary resources covers a broad range of concentrations, the applied solutions were obtained by digesting in aqua regia WEEE characterized by relatively high (Central Processing Units, CPU) and relatively low (Pin Contact Elements, PIN) amounts of gold. The investigated systems were received after processes of enrichment and leaching, ignoring the usually applied WEEE processing reduction and solvent-extraction processes, keeping the amount of generated wastes to a minimum. The obtained CPU and PIN solutions were then directly contacted with core–shell type anion exchange resins functionalized using ethylenediamine and 1-(2-aminoethyl)piperazine. Application of the designed polymers allowed the process of aqua regia-leaching, omitting the application of other, more harmful agents.The investigated resins revealed great selectivity towards gold. Despite the fact that the obtained solutions contained only 1.5% (CPU) or 0.1% (PIN) of Au, its removal reached 86% and the logarithms of partition coefficients indicate that affinity of the applied resins to gold is almost ten times greater than the very competitive nickel present in the obtained solutions. Finally, the gold-containing core–shell polymers were effectively eluted, recovering 100% of the taken from the solutions gold. Keywords: E-scrap, Leaching, Anion exchange

A method for the synthesis of anion-exchange membranes by the grafting of ethylenediamine (EDA), diethylenetriamine (DETA) or pentaethylenehexamine (PEHA) onto poly(vinyl chloride) (PVC) film has b...

Phthalate esters are widely used in production of polymer materials (approximately five millions tones annually), therefore they occur in final products (food packages, cosmetics, vinyl products) and undergo emission into the environment. Phthalates have a negative impact on living organisms (e.g. disturbing function of endocrine/reproductive systems) and some of them are restricted (REACH, U.S. CPSC). Investigating their occurrence in the environment, especially indoor/outdoor air, is very important. After several improvements in recent years (e.g. heating/cooling efficiency), sorption of analytes on sorbent followed by thermal desorption (TD) and GC–MS seems to be the best suited protocol to determine phthalates in air samples. It is a straightforward technique, without dilution of samples and use of toxic solvents. However, it cannot be applied to compounds which are thermally unstable and have a low vapor pressure. Overall, TD it is one of the best available technique for desorption of phthalates from a sorbent.

The pH-responsive molecularly imprinted polymers (SR-MIPs) for the removal of dibutyl phthalate (DBP) were obtained. The polymers were synthesized using methyl methacrylate, methacrylic acid, divinylbenzene and a template mixed at different ratios allowing to optimize the process. The so-prepared SR-MIPs were evaluated at various pH in processes of DBP sorption. The studies covered evaluation of uptake capacity, sorption kinetics, selectivity and elution. The imprinted samples are characterized by improved factors comparing to their non-imprinted analogues, revealing also pH-sensitivity. The highest removal of DBP (130 mg g−1) was achieved at pH=6, while pH-driven desorption (90%) was the most efficient at pH=8.

International audience; We characterize the structure of two Cu(II) complexes of 7-hydroxycoumarins in organic solvents. The solvents are, dimethyl sulfoxide and dimethylformamide. X-ray absorption spectroscopy together with density functional theory calculations are employed to identify the structural changes induced by the two solvents in comparison to the solid form of complexes. We show that the structure of the Cu(II) complexes is modified depending on the solvent and we propose the geometry of the complexes molecule.

Achiral stilbene polycatenars forming smectic, columnar or cubic phase depending on the terminal chains length, were studied. The cubic Im3m phase exhibited optical activity originating in twisted face-to-face molecular aggregates. The optical activity of the phase is preserved upon sample crystallization, providing evidence of a transfer of chirality on a molecular level.

The paper focuses on preparation of dual purpose porous prefilter that can serve either as a filter or sorbent for removal of bisphenol A. To obtain such materials, a possibility to form imprinted layer of methyl methacrylate and ethylene glycol methacrylate copolymer was evaluated. The layer was grafted to plasma activated porous polypropylene filters. It was noted formation of some patches on the surface for lower grafting yield. The patches increased their size up to formation of continuous layer. It was noted that optimization of grafting parameters should be performed separately and the use of the same protocol as for bulk polymerization of molecularly imprinted polymers could not be applied. The dual purpose prefilters were able to catch bisphenol A during filtration and its concentration was reduced significantly while other phenol derivatives were not adsorbed. By the use of molecularly imprinted filters, the removal of bisphenol A was four time higher than that removal on non-imprinted membranes. The best sorption properties were obtained for materials grafted by monomers with 4:6 M ratio of methyl methacrylate to ethylene glycol dimethacrylate. The static sorption reached the value of 0.06 mmol g−1 and bisphenol A was rejected at 70% level in filtration of 0.2 mM BPA aqueous solution.

Recent years have seen the increased utilization of ionic liquids (ILs) in the development and optimization of analytical methods. Their unique and eco-friendly properties and the ability to modify their structure allows them to be useful both at the sample preparation stage and at the separation stage of the analytes. The use of ILs for the analysis of pharmaceuticals seems particularly interesting because of their systematic delivery to the environment. Nowadays, they are commonly detected in many countries at very low concentration levels. However, due to their specific physiological activity, pharmaceuticals are responsible for bioaccumulation and toxic effects in aquatic and terrestrial ecosystems as well as possibly upsetting the body’s equilibrium, leading to the dangerous phenomenon of drug resistance. This review will provide a comprehensive summary of the use of ILs in various sample preparation procedures and separation methods for the determination of pharmaceuticals in environmental and biological matrices based on liquid-based chromatography (LC, SFC, TLC), gas chromatography (GC) and electromigration techniques (e.g., capillary electrophoresis (CE)). Moreover, the advantages and disadvantages of ILs, which can appear during extraction and separation, will be presented and attention will be given to the criteria to be followed during the selection of ILs for specific applications.

A gas chromatography-mass spectrometry (GC–MS) method to determine polar and thermally unstable phthalate metabolites [monomethyl phthalate–MMP, monoethyl phthalate–MEP, mono-n-butyl phthalate–MnBP, mono-(2-ethylhexyl) phthalate–MEHP] has been developed. This is the first report presenting the separation of monophthalates without derivatization step and any additional equipment or special injection port. Injection parameters (temperature, pressure, time, and volume of injection), chromatographic separation (retention gap, temperature program), and MS detection/identification (working parameters, ion selection) were investigated. Mechanisms and phenomena occurring under different conditions in the GC injector were evaluated and discussed. The limits of detection (LODs) of MMP, MEP, MnBP, MEHP in the protocol were 0.049, 0.036, 0.038, and 0.029 ng (per 2 μL of injection), respectively. The response of the monophthalates was found to be linear in the tested concentration range (for MMP: 0.15–100 ng, MEP and MnBP: 0.11–100 ng, MEHP: 0.087–100 ng per 2 μL) with the coefficient of determination higher than 0.9817 and inter-day precision in the range of 1.4–5.4%. The developed method is fast, easy and repeatable. Moreover, it allows for the elimination of derivatization agents, reduction of toxic waste production and simplification of analytical procedure.

International audience; The unambiguous characterization of the coordination chemistry of nanocrystal surfaces that have been produced by a wetchemical synthesis presently remains a highly challenging issue. Here, zinc oxide nanocrystals (ZnO NCs) coated by monoanionic diphenyl phosphate (DPP) ligands were derived by a traditional sol-gel process and a one-pot self-supporting organometallic (OSSOM) procedure, and advanced atomic-scale characterization through dynamic nuclear polarization (DNP-)enhanced solid-state nuclear magnetic resonance (ssNMR) spectroscopy has notably enabled resolving their vastly different surface-ligand interfaces. For the OSSOM-derived NCs, DPP moieties form stable and strongly-anchored µ2-and µ3-bridgingligand pairs that are resistant to competitive ligand exchange processes. Contrastingly, the sol-gel-derived NCs contain a wide variety of coordination modes of DPP ligands and a ligand exchange process takes place between DPP ligands and glycerol molecules. This highlights the power of DNP-enhanced ssNMR for detailed NC surface analysis and the superiority of the OSSOM approach for the preparation of high quality ZnO NCs.

Each drug has pharmacokinetics that must be defined for the substance to be used in humans and animals. Currently, one of the basic analytical tools for pharmacokinetics studies is high-performance liquid chromatography coupled with mass spectrometry. For this analytical method to be fully reliable, it must be properly validated. Therefore, the aims of this study were to develop and validate a novel analytical method for 4-acetamidobenzoic acid, a component of the antiviral and immunostimulatory drug Inosine Pranobex, and to apply the method in the first pharmacokinetics study of 4-acetamidobenzoic acid in pigs after oral administration. Inosine Pranobex was administered under farm conditions to pigs via drinking water 2 h after morning feeding at doses of 20, 40, and 80 mg/kg. For sample preparation, we used liquid–liquid extraction with only one step—protein precipitation with 1 mL of acetonitrile. As an internal standard, we used deuterium labeled 4-acetamidobenzoic acid. The results indicate that the described method is replicable, linear (r2 ≥ 0.99), precise (2.11% to 13.81%), accurate (89% to 98.57%), selective, and sensitive (limit of quantitation = 10 ng/mL). As sample preparation requires only one step, the method is simple, effective, cheap, and rapid. The results of the pilot pharmacokinetics study indicate that the compound is quickly eliminated (elimination half-life from 0.85 to 1.42 h) and rapidly absorbed (absorption half-life from 0.36 to 2.57 h), and that its absorption increases exponentially as the dose is increased.

A step-by-step synthesis based on the application of monoprotected 2.6-diformylpyridine intermediate resulted in the formation of enantiopure Eu(III), Yb(III) and Y(III) complexes of unsymmetrical macrocycles L3 and L4 containing two pyridine units and two different diamine and diimine links. The final step in the formation of these mixed amine-imine hexaazamacrocycles was based on a templated condensation of ethylenediamine or enantiopure trans-1,2-diaminocyclohexane with a linear [2 + 1] amine intermediate bearing two pyridinecarboxaldehyde fragments. The identity of these unsymmetrical complexes have been determined on the basis of 2D NMR and ESI MS spectroscopy and confirmed by the X-ray crystal structures of Eu(III) and Yb(III) complexes of macrocycle L3. In these complexes the macrocyclic ligand adopts twist-fold conformation and the twist of the achiral ethylene link is dictated by the conformation of the cyclohexane link. The ten-coordinate Ln(III) ions are bound in equatorial positions by the six nitrogen atoms of the macrocycle and their coordination spheres are completed by two axial bidentate nitrate anions. The luminescent properties of the Eu(III) complexes of L3 and L4 have been characterized.

Human urine is one of the most important fluids providing useful information about the body condition. The composition of urine can be used to monitor disease treatment, as a diagnostic tool in clinical chemistry and in the evaluation of occupational or environmental exposure. The chemical composition of urine is complex and shows a high variation of matrix elements. Therefore, the analysis of urine components requires the choice of an appropriate analytical technique. This review helps to update and systematize the analytical techniques which have been used for years in urine analysis. Particular attention is paid to the progress of analytical methods pointing advantages and drawbacks of the various techniques used for separation and determination of urine components. The basic characteristics and application instances of the existing determination methods are introduced, including spectrometry, chromatography and indication tests.

It was found that for H-shape dimers, the parity of the number of atoms in the spacer linking the mesogenic cores has important influence on the mesogenic properties only for the molecules with weak mesogenic core anisotropy. In the case of stronger core anisotropy, the parallel arrangement of mesogenic units is induced regardless of the spacer parity. As a result, phase transition temperatures and layer spacing are only weakly affected by spacer parity. By studying the properties of six new homologue series it was found that for H-shape dimers the orthogonal smectic (SmA) is strongly disfavoured: most compounds form a tilted smectic (SmC) phase, which is related to hindrances in molecular rotation for molecules with large breath to length ratio. For dimers with very long spacer, and thus decoupled mesogenic units, the smectic phase is replaced by a nematic phase, and for stiff polycatenar molecules with very short spacers the cubic phase can appear.

This growing interest in the cultivation of Japanese quince Chaenomeles japonica L. results from the potentially beneficial properties of its fruit. Fresh fruits are very firm and too acidic to eat raw, but their bioactive components, distinctive aroma, and high amount of dietary fiber make the fruits well suited for industrial processing. However, not all the properties of the fruit have been investigated. For example, there are no comprehensive reports about the mineral content or potentially harmful effects on liver metabolism. Hence, the purpose of our study was to examine fresh Japanese quince fruit in terms of (1) ascorbic acid, oxalate, fiber, macro- and micronutrients, dry matter, extract, total acidity, antioxidant activity, and phenolic compound levels; and (2) the effect of its extract on in vitro hepatocyte metabolism, measured by the concentration of lipid peroxides (LPO) and reactive oxygen species (ROS) and the severity of apoptosis and necrosis. The fruit of C. japonica had high levels of macro- and microelements, ascorbic acid, phenolic compounds, fiber, and low oxalate levels. Our analysis of macro- and microelements showed that the average content of Fe was 0.516 mg/g, Cu 0.146 mg/g, Zn 0.546 mg/g, Mg 16.729 mg/g, and Ca 22.920 mg/g of fresh fruit. A characteristic feature of the fresh fruit of C. japonica is a high level of polyphenols, which—combined with a high content of vitamin C—affect their high antioxidant potential. In the tested hepatocyte cultures incubated with extract of the Japanese quince, we observed a significant decrease in the concentration of lipid peroxides compared to the control. There were also no signs of increased formation of ROS in the mitochondria of hepatocytes incubated with the extract of quince. Malondialdehyde was strongly negatively correlated with the concentration of Japanese quince extract, which indicates the hepatoprotective properties of Japanese quince. In addition, our analysis of confocal microscopy images showed that the hepatocytes incubated with the extract of Japanese quince at any concentration did not show any signs of apoptosis or necrosis. The aqueous extract of quince fruit has antioxidative and antiapoptotic hepatocytes, thus exerting a hepatoprotective effect.

The Co(II), Ni(II) and Cu(II) complexes with herbicide 2,4–dichlorophenoxyacetic acid (2,4-D) were synthesized and structurally characterized. The geometry of metal-ligand interaction was refined using XAFS and DFT studies. The Co(2,4-D)2·6H2O and Ni(2,4-D)2·4H2O complexes have octahedral geometry with two carboxylate groups of 2,4-D anions and four water molecules in the coordination sphere. The square planar geometry around metal cations formed by the carboxylate groups from two monodentate ligands and two water molecules, is observed for Cu(2,4-D)2·4H2O complex. In the recrystallized Ni(II) complex dinuclear ‘Chinese lantern’ structures with bridging carboxylate groups of 2,4-D were observed.

The aim of the study was to assess the value of the breaking force of the bonding between selected polymer cements, root dentin and fiber reinforced composite (FRC) posts. Five resin based luting cements were selected for use in the study. Tests were performed on a total of 30 teeth, which were divided into two groups. Fifteen teeth were installed vertically and 15 with an angle of 45°. All samples were exposed to crushing forces in an Instron 4411 device. After the strength tests, each sample was analyzed by micro-CT (micro computed tomography) in order to verify that the forces did not cause defects in the areas of the adhesive connection. The differences observed in the present study only involved the posts that failed at different values of the acting forces – in the case of the vertical sample, x =532.5 N and in the case with an angle of 45°, x = 117.9 N. For the micro-CT images, there were no defects in the analyzed areas of the adhesive connections. Under the conditions of the current study, all selected polymer cements showed the required level of bonding.

In the paper, a modified method for elemental sulfur (S8) determining using gas chromatography coupled with mass spectrometry (GC-MS) is proposed with estimation of selected validation parameters. The aim of this work was a review of problems associated with the determination of S8 and selection of the most optimal conditions for S8 analysis with GC-MS. The presented studies have shown that the temperature of the injector and the chromatographic column during S8 determination should not exceed 180 °C. At temperatures over 180 °C, the sulfur S8 is decomposed to the other sulfur species such as S2, S3, S4, S5, and S6. During decreasing injector and column temperature below 180 °C the chromatographic peak eluted as S8 is badly extended and asymmetric. To minimize the problems of S8 decomposition to other sulfur species during chromatographic process also other parameters of the GC-MS have been selected. In order to apply the proposed method for real sediments samples, determination of sulfur S8 in bottom sediments, collected in the Gulf of Gdansk (southern Baltic Sea), has been performed. The concentration of S8 fell in the range from below the limit of detection to 0.1432 ± 0.0095 mg/g d.w. The research has also shown that addition of approx. 200 mg of activated copper is effective for removing sulfur from bottom sediment extracts.

Microwave hydrothermal growth of Y2O3 crystallites results in needle-shaped aggregates of μm length. Thermal treatment has little influence on the material microstructure, but significant impact on the nanometric level. Nanoparticles doped with europium show an intense red luminescence, related to the 5D0 → 7F2 transition of Eu3+ ions. The luminescence intensity increases with the calcination temperature and is accompanied by increasing size of Y2O3:Eu crystallites. EPR studies show the absence of Eu2+ related signals in the material. Y2O3:Eu nanoparticles crystallized via a microwave hydrothermal method were employed as luminescent biomarkers in mice. The initial tests confirmed their applicability as biological markers. Persorption of the Y2O3:Eu nanoparticles after IG in the adult mouse duodenum, brain and liver is reported.

In this paper a new generation of non-toxic nanoparticles based on the zirconium oxide doped with 0.5%Tb and co-doped by the range of 0–70% with Y was evaluated for the use as a fluorescent biomarker of neuronal trafficking. The ZrO 2 :Tb nanoparticles were created by microwave driven hydrothermal method. Influence of the yttrium content and thermal processing on the Tb 3+ related luminescence emission was discussed. The higher intensities were achieved, when host was cubic and for the nanoparticles with 33 nm. Presence of yttrium was associated with the energy coupling of the host and dopant, wide excitation band is present at 309 and 322 nm before and after calcination respectively. For the experiment on living primary neurons, nanoparticles doped with 0.5%Tb and 7%Y were chosen based on their luminescence emission intensity. Recently transfer of the nanoparticles through the barriers in the organism including blood–brain barrier following their alimentary absorption was confirmed (Godlewski and Godlewski, 2012). This raised the possibility of the nanoparticle application as a tool in the neuroscience, and the question of potential mechanisms of nanoparticle turnover in neurons. Concentration of 0.001 mg/ml of ZrO 2 :0.5%Tb 7%Y in growth medium was added to the primary murine culture medium, and the intracellular trafficking of nanoparticles was observed following 15 min pre-incubation period. ZrO 2 :0.5%Tb 7%Y nanoparticles were dynamically absorbed by the neurons and the dynamic passage of transport vesicles containing ZrO 2 :0.5%Tb 7%Y nanoparticles was observed along the neuronal processes and in between two neighbouring neurons. Reassuming, the ZrO 2 :0.5%Tb 7%Y nanoparticles proved to be biocompatible and a valid tool to assess intracellular trafficking dynamics in the neurobiology.

A series of newly synthesised rod-like polycatenar mesogens forms columnar phases, with the number of molecules in the column cross section depending on the core rigidity. For non-symmetric molecules, an additional density modulation, namely helical arrangement of molecules with a periodicity of approximately 10 molecular distances develops along the columns. For one of the compounds, a new type of columnar liquid crystal phase with 3D positional order is observed. Introducing a stilbene unit in the mesogenic core enhances the fluorescent properties of the compounds. In the hexagonal columnar phase, polarised light emission is observed.

A thermoresponsive molecularly imprinted polymer (T-MIP) for removal of diethyl phthalate (DEP) was obtained. The polymer was synthesized using N-isopropylacrylamide (NIPAM), methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA). The studies have been focused on a selection of monomers composition and kind of solvent. The ability of molecular recognition towards DEP was evaluated. The obtained MIPs showed temperature-sensitive sorption comparing to non-imprinted analogues. The greatest affinity towards template was observed at 35°C for sorbent prepared from NIPAM:MMA of 3:7 ratio, with the 60% of crosslinker and toluene as a solvent. The best conditions for DEP desorption were noted at 60°C.

A new possibility for the formation of macroscopic and photoactive structures from zinc oxide nanocrystals is described. Photoactive freely suspended and free-standing films of macroscopic area (up to few square millimeters) and submicrometer thickness (up to several hundreds of nanometers) composed of carboxylate ligand-coated zinc oxide nanocrystallites (RCO2-ZnO NCs) of diameter less than 5 nm are prepared according to a modified Langmuir-Schaefer method. First, the suspension of RCO2-ZnO NCs is applied onto the air/water interface. Upon compression, the films become turbid and elastic. The integrity of such structures is ensured by interdigitation of ligands stabilizing ZnO NCs. Great elasticity allows transfer of the films onto a metal frame as a freely suspended film. Such membranes are afterward extracted from the supporting frame to form free-standing films of macroscopic area. Because the integrity of the films is maintained by ligands, no abolishment of quantum confinement occurs, and films retain spectroscopic properties of initial RCO2-ZnO NCs. The mechanism of formation of thin films of RCO2-ZnO NCs at the air/water interface is discussed in detail.

A series of nine copper complexes were synthesized by reacting 1,3-disubstituted thioureas with copper(II) chloride. The new compounds were characterized by elemental analysis, infrared, ultraviolet-visible and X-ray absorption spectroscopies as well as molecular modelling. The molecular structure of complexes in the solid state consists of two thiourea ligands chelated to the Cu(II) ion through the S and deprotonated N atoms (CuN2S2). The coordination polyhedron of metal cation in powdered samples exhibits two different geometries. Pseudo-tetrahedral structure is observed for noncentrosymmetric complexes with cis-N2S2 arrangement around Cu(II). A distorted square planar geometry is characteristic for centrosymmetric compounds with trans arrangements of chelating atoms around the central ion. All complexes after dissolving in dimethyl sulfoxide adopt a centrosymmetric coordination, while after diluting this solution with water, the reorganization of atoms around the metal cation is observed, leading to the formation of a tetrahedral compounds. Initial ligands and Cu(II) complexes were evaluated for their cytotoxicity. Two complexes with 4- and 3-bromophenyl attached to the (1,7,8,9,10-pentamethyl-3,5-dioxo-4-azatricyclo[5.2.1.02,6]dec-8-en-4-yl)thiourea moiety (Cu1, Cu3) are cytotoxic against SW480 and PC3 cells (IC50 4–19 μm), and non-cytotoxic against HaCaT cells (IC50 ≥ 84 μm), being more selective than doxorubicin and cisplatin used as references. The compounds induced apoptosis in cancer cells, however, Cu3 was estimated to be highly active inducer of late apoptosis in SW480 and PC3 cells at lower toxicity against normal cells. The likely mechanism of action of complexes is correlated with decreasing release of IL-6 in cancer cell lines.

Series of partially sulfonated poly(F-STs-co-ST) copolymers and poly(TFMST-ter-ST-ter-FMST) terpolymer have been successfully synthesized via post-sulfonation method using acetyl sulfate as a sulfonating agent. The identical and mild sulfonation conditions with a controlled sulfonation degree (SD) in the range of 18-27 mol%, were designed for comprehensive evaluation of the effect of fluorine content on the efficiency of the electrophilic -SO3H substitution. The SD values of the sulfonated FAPs were determined using elemental analysis (EA). The identical, effective and versatile isolation method for all sulfonated polymers, regardless the amphiphilic dual nature of the resulting polymers (hydrophobic fluorine-containing, and also hydrophilic sulfonated unit) and also the presence of different fluorinated methyl moieties (-CH2F, -CF2H and -CF3) in polymeric chain, was developed. The resulting novel sulfonated FAPs were characterized by NMR and FTIR spectroscopies that evidenced a satisfactory incorporation of -SO3H functions into aromatic rings of polymer chain. Studies clearly revealed that the electron-deficient aromatic rings of F-ST units did not undergo sulfonation in comparison with electron-rich aromatic rings of ST units. The FTIR and 1H NMR analysis showed that the sulfonation occurred only in aromatic rings of the ST units and -SO3H functions were introduced at the para position. Moreover, with an increase of the fluorine content in polymer structure, a decrease in the resulting SD values was noticed. The presence of fluorine reduced the electron density directly in fluorinated aromatic units (F-STs), and surprisingly gently affected neighboring ST units. The thermal properties of the resulting copolymers were investigated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The observed higher Tgs values of sulfonated polymers than those of unsubstituted counterparts indicated that the increase in the structural rigidity of the resulting materials as a function of the increase of the amount of sulfonic groups. Finally, the XPS analysis proved that under these conditions undesired sulfone crosslinking did not occur.

We demonstrate for the first time a highly efficient Cu(i)-catalyzed alkyne-azide cycloaddition reaction on the surface of ZnO nanocrystals with retention of their photoluminescence properties. Our comparative studies highlight the superiority of a novel self-supporting organometallic method for the preparation of brightly luminescent and well-passivated ZnO nanocrystals over the traditional sol-gel procedure.

Equimolar reactions between ZntBu2 and diphenyl phosphate (dpphe-H) or dimethyl phosphate (dmphe-H) result in the formation of [tBuZn(O2P(OR')2)]-type compounds which crystallize as tetranuclear aggregates, [tBuZn(dpphe)]4 (14) or [tBuZn(dmphe)]4 (24), with the phosphate ligands spanning 4-coordinate Zn centers. The utility of ZnMe2 instead of ZntBu2 dramatically changes the reaction outcome and leads to [MeZn(O2P(OR')2)]-type moieties incorporating zincoxane units, i.e., pentanuclear [{MeZn(dpphe)}3(Me2Zn2O)(THF)2] (3) and nonanuclear [{MeZn(dmphe)}6(Me2Zn3O2)] (4) aggregates. The resulting compounds were characterized by 1H and 31P NMR spectroscopy and single-crystal X-ray diffraction analysis.

5th International Conference on Functional Materials and Devices (ICFMD) -- AUG 04-06, 2015 -- Johor Bahru, MALAYSIA, WOS: 000371028300003, Due to the connecting one pi -conjugated group with the two backside donor and acceptor groups, anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene (1) might possess nonlinear optical (NLO) properties. To estimate the potential for second-order NLO behaviour; the electric dipole moments and dispersion-free dipole polarizabilities and first hyperpolarizabilities have been determined by density functional theory (DFT) at B3LYP/6-31++G(d, p) level. Quantum mechanical calculations using time-dependent Hartree-Fock (TDHF) procedure have been utilized to evaluate frequency-dependent second-order nonlinearities of 1. The one-photon absorption (OPA) characterization of 1 has been theoretically obtained by means of configuration interaction (CI) with 6-31G basis set. Our theoretical results on the maximum OPA wavelength, second-order susceptibilities and corresponding microscopic NLO responses are accorded with the previous experimental observations of the investigated compound. The highest occupied molecular orbitals, the lowest unoccupied molecular orbitals and the HOMO-LUMO band gaps for 1 have been also examined by DFT/B3LYP method. (C) 2016 The Authors. Published by Elsevier Ltd.

The new Cu(II) complexes with 6-acetyl-7-hydroxy-4-methylcoumarin (HL1) and 8-acetyl-7-hydroxy-4-methylcoumarin (HL2) have been obtained by the electrochemical method. The density functional theory calculations and X-ray absorption spectroscopy techniques have been used to geometrically describe a series of new compounds. The studies have been focused on the coordination mode of the hydroxy ligands to the metallic centre. The complexes, Cu(HL1)2 and Cu(HL2)2⋅0.5H2O, have flat square geometry with oxygen atoms in the first coordination sphere. Two bidentate anionic coumarins are bonded to the metal cation via the acetyl and deprotonated hydroxyl O atoms. Biological activity, including microbiological and cytotoxic, has been evaluated and found to be enhanced in comparison with the parent ligands. Moreover, the Cu(II) complex with 8-acetyl-7-hydroxy-4-methylcoumarin shows similar antifungal activity as commercially used fluconazole.

The preparation of ZnO nanocrystals with enhanced stability and photoluminescence intensity in an aqueous environment is a challenging task. We report on an one-pot two-step organometallic approach for the synthesis of processable alkyne-functionalized quantum-sized ZnO crystals and their efficient phase transfer protocol from an organic solvent to an aqueous environment involving the surface modification by the Cu-mediated azide–alkyne cycloaddition. Remarkably, the water-soluble NCs not only maintain the photoluminescence properties after the post-synthetic surface modification, but also exhibit the unprecedented (for II–VI semiconductor nanocrystals) aggregation enhanced emission phenomenon.

International audience; A study on the α-(difluoromethyl)styrene (DFMST) reactivity under conventional radical copolymerization conditions is presented. Although the homopolymerization of DFMST failed, its radical bulk copolymerization with styrene (ST) led to the synthesis of fluorinated aromatic polymers (FAPs). The resulting novel poly(DFMST-co-ST) copolymers were characterized by 1H, 19F and 13C NMR spectroscopies that evidenced the successful incorporation of DFMST units into copolymers and enabled the assessment of their respective molar percentages (10.4–48.2 mol%). The molar masses were in the range of 1900–17 200 g mol−1. The bulkier CF2H group in the α-position induced the lower reactivity of the DFMST comonomer. ST and DFMST monomer reactivity ratios (rDFMST = 0.0 and rST = 0.70 ± 0.05 at 70 °C) were determined based on linear least-square methods. These values indicate that DFMST monomer is less reactive than ST, retards the polymerization rate, and thus reduces the molar masses. Moreover, the thermal properties (Tg, Td) of the resulting copolymers indicate that the presence of DFMST units incorporated into poly(ST) structure promotes an increase of the Tg values up to 109 °C and a slightly better thermal stability than that of poly(ST). Additionally, the thermal decomposition of poly(DFMST-co-ST) copolymer (10.4/89.6) was assessed by simultaneous thermal analysis coupled with Fourier-transform infrared spectroscopy and thermogravimetric analysis coupled with mass spectrometry showing that H2O, CO2, CO and styrene were released. The surface analysis was focused on the effects of the –CF2H group at the α-position of styrene comonomers on surface free energy of the copolymer films. Water and diiodomethane contact angle (CA) measurements confirmed that these copolymers (Mn = 2300–17 200 g mol−1) are not exactly the same as polystyrenes (Mn = 2100–21 600 g mol−1) in the solid state. The CA hysteresis for poly(ST) (6–8°) and poly(DFMST-co-ST) copolymers (3–5°) reflected these differences even more accurately.