Volume 9, Issue 2

The synthesis of the potential molecular receptors in the amination-reduction reaction has been investigated within the model system comprising (2-formylphenyl)boronic acid and morpholine. The 3-amine substituted benzoxaborole was identified to be the intermediate of the synthesis and the unsubstituted benzoxaborole as the by-product resulting from reduction of the starting material. The insight into the reactivity of the starting materials as well as the intermediate benzoxaborole enabled significant rise in the yield of 2-(aminomethyl) phenylboronic acids synthesis. The solid state structure of 2-(piperidylmethyl)phenylboronic acid has been re-determined, and the description of the molecule and the crystal is given. The supramolecular layer structure directed by the weak C-H…O and C-H…π interactions was identified and scrutinized based on the geometry and Hirshfeld surface analyses

This article discusses the preparation of different polymeric sorbents for solid phase extraction. Various monomers like acrylamide, methacrylic acid and 4-vinylpyridine (VP), cross-linkers such as divinylbenzene (DVB) and ethyleneglycoldimethacrylate (EDMA), porogens like tetrahydrofuran (THF) and dimethylsulphoxide (DMSO) / acetonitrile (ACN) with different ratios were investigated in order to optimize recoveries. Resulting polymers were characterized through scanning electron microscope (SEM) and compared with Oasis HLB (Waters, MA, USA) and Strata-X (Phenomenex, Torrance, USA) on the basis of extraction performance, recovery efficiency and loading capacity. Sample applied was a mixture of flavonoid standards (rutin, myricetin, luteolin, quercetin, apigenin and kaempferol). HPLC hyphenated with PDA was used for the analysis of samples. Results showed that among the prepared SPE materials, 4-VP-co-EDMA produced best results. Comparison of the produced polymers with of Oasis HLB and Strata-X resulted in comparable efficiencies; especially the polymer 4-VP-co-EDMA gave almost similar results for all analytes to those of commercially available SPE materials. A general trend of decrease in retention efficiency with increase in polarity has been observed in both synthesized and already available SPE materials. The newly synthesized polymeric materials can be employed as SPE sorbents for efficient extraction of polyphenolic compounds especially for flavonoid aglycons.

A multi-element analytical method based on inductively coupled plasma atomic emission spectrometry (ICP-AES) was developed for trace elements in pharmaceutical tablets and cosmetics. Titanium was also included in the analytes since it is widely used in pharmaceuticals. Critical ICP conditions, like RF incident power, argon gas flow rate and nebulizer sample uptake flow rate were optimized. The most sensitive spectral line of each analyte was selected as optimum for further study. Detection limits in the low µg g−1 range were obtained. Prior to chemical analysis, the samples were decomposed by acid digestion, using various mixtures of HCl, HNO3 and HF. Yttrium was used as a suitable internal standard in order to correct for possible matrix effects. The method was applied to the analysis of six different pharmaceutical products (anti-biotic, anti-inflammatory, anti-hypertensive) in the form of tablets with film coating and also three cosmetic products like hair and face masks.

The synthesis and photophysical properties of several 6,6″ symmetrically substituted 4′-aryl-2,2′:6′,2″-terpyridine derivatives are reported herein. The UV-Vis spectra in acetonitrile as well as in dichloromethane show two intense bands in the UV areas 252–262 nm and 275–290 nm while the fluorescence emission spectra are only slightly influenced by chemical derivatization.

Reaction of [CuII(cyclam)](ClO4)2 or [NiII(cyclam)](ClO4)2 in DMF with aqueous 4-hydroxy-3-(4-sulfonato-1-naphthylazo)naphthalen-1-sulfonate disodium salt (carmoisine) yielded coordination polymers {[CuII(cyclam)](carmoisine dianion)(H2O)5}n and powder {[NiII(cyclam)](carmoisine dianion)}n, respectively (cyclam = 1,4,8,11-tetrazacyclotetradecane). They were characterized by powder X-ray diffraction, IR, Raman spectrometry and TGA.

In this work the application of hybrid materials, containing TEOS as source of SiO2 and k-carrageenan in different percentage, synthesized by the sol-gel method at room temperature was studied. They were used as matrices for entrapment of whole Bacillus sp. UG-5B cells, producers of thermostable nitrilase. The effect of the surface area and size and quantity of pores in the synthesized materials on the enzyme activity was evaluated. The process of biodegradation of different concentrations of toxic, potentially carcinogenic and mutagenic substrates by the obtained biocatalysts was investigated. The enzyme reaction takes place by the nitrilase pathway, catalysing nitrile hydrolysis directly to the corresponding carboxylic acid, forming ammonia. At batch experiments the influence of the substrate concentration of different nitriles was tested and 20 mM concentration was found most suitable. A two-step biodegradation process in a laboratory-scale column bioreactor of o-, m- and p-tolunitrile as a mixture was followed. After operation of the system for nine hours for the mixture of substrates at a flow rate of 45 mL h−1 and at 60°C, the overall conversion realized was above 90%, showing a good efficiency of the investigated process.

Iron catalyst for ammonia synthesis of various mean sizes of iron nanocrystallites were nitrided with ammonia in a differential reactor equipped with systems that made it possible to conduct both thermogravimetric measurements and hydrogen concentration analyses in the reacting gas mixture. The nitriding process was investigated under atmospheric pressure at the temperature of 475°C. It was found that along with an increase of mean size of iron nanocrystallites, with a decrease of specific surface area of the samples, nitriding degree of solid samples increased. At the same time the rate of surface reaction of catalytic ammonia decomposition decreased. Along with an increase of the samples’ specific surface area an increase of the catalyst’s activity was observed. However, it was also observed that the concentration of active sites on the catalysts’ surface decreased along with an increase of specific surface area.

Samples of human serum albumin (HSA) obtained as a result of heat denaturation followed by refolding controlled by a cooling of the protein solution were studied by several methods: chromatographic measurements, kinetic of the reaction with a water soluble free radical and by electron paramagnetic resonance (EPR) spectroscopy. In this context the interaction of this protein with β-cyclodextrin (β-CD) and sodium dodecyl sulfate (SDS) was also investigated. Reversed phase thin layer chromatography (RP-TLC) showed changes in lipophylicity of HSA, which are related with the existence of different ensembles of conformers. The UV-Vis absorption spectra had shown the broadening of absorption band of the protein and a hyperchrom effect in the presence of SDS; β-CD reduces the effect of SDS on protein UV-Vis spectra. Kinetic measurements related to the reaction of HSA with a water soluble DPPH type free radical provided evidence that reactivity of the HSA denaturated conformers is higher compared with the natural conformer. The affinity of SDS to the albumins surface and the effect of β-CD on the SDS/protein aggregates were also evident by changes in the EPR spectra of the spin probe CAT16.

Tautomerism of benzaurins and hydration are studied. 1H and 19F chemical shifts have been determined for a number of substituted 4-hydroxyphenyl-diphenyl carbinols containing fluorine in a 3-, 3*- or 4*-position, and for similar compounds containing additional methyl groups in a position of 3, 3** or 4**. The same data have been obtained for the fuchsones prepared by dehydration of the above carbinols. On this basis chemical shifts of fluorine in different positions have been evaluated as a monitor of the transformation of 4-hydroxyphenyl group to the semiquinone moiety. The 19F NMR can be used to monitor the transformation of 4**-fluorobenzaurin and the related 3,3*-disubstituted and 3,3*,5,5*-tetramethylsubstituted compounds to the corresponding carbinols due to the addition of a water molecule and to study the tautomerism of the two latter benzaurins as well as that of 3,3*,4**trifluorobenzaurin. Furthermore, fluorine and methyl group chemical shifts are sensitive to syn-anti-isomerism in substituted fuchsones. The prototropic process of these compounds may be slow or fast on a 1H NMR time scale depending on the solvent and may be catalyzed by water or carbonic acids. On the basis of kinetic and thermodynamic data obtained by dynamic NMR studies, a mechanism for the process has been proposed.

The paper presents an example of using multivariate techniques to interpret a large data set obtained during a 4-year water quality monitoring program in the Gdansk Municipality region, on the southern coast of the Baltic Sea. From 2004 to 2007, 11 physicochemical water parameters were analyzed monthly at 15 sites within eight watercourses. Principal-components analysis and cluster analysis were used to explore the data. Spatio-temporal trends in water quality were evaluated, the variables that determined the data set’s structure and the factors that affected the water’s physicochemical composition identified, with the goal of helping to optimize future monitoring. To reduce the number of analyzed variables, relationships between the analyzed parameters were also identified. The results revealed that the differences in physicochemical water properties among stations were generally smaller than those between the warmer and cooler seasons. It was determined that seasonal intrusions of brackish water from the Gulf of Gdansk can modify the water properties of some watercourses in the study area, but that dissolved oxygen, chemical oxygen demand, and total phosphorus were the main parameters responsible for the overall variation in the observed data. These parameters are related to pollution of anthropogenic origin.

Three layered double hydroxides (LDH) [Mg1−xAlx(OH)2]x+(Am−)x/m]·nH2O and [MII 1−xMIII x (OH)2]x+(Am−)x/m]·nH2O (MII — Mg, Co, Ni; MIII — Al; A — CO3 2−) were successfully synthesized by the low supersaturation method. The as-synthesized LDH samples were thermally decomposed and the derived mixed metal oxides reformed back to layered structures in water and magnesium nitrate media at different temperatures. All synthesized samples were characterized by X-ray diffraction (XRD) analysis, thermogravimetric (TG) analysis, X-ray fluorescence (XRF) analysis and scanning electron microscopy (SEM). The results of XRD and XRF analyses showed that single-phase layered double hydroxides were formed during synthesis and reformation. It was demonstrated, that a partially substituted by cobalt and nickel LDH samples also show memory effect. The crystallite size of regenerated LDH depends on the regeneration media, temperature and chemical composition. The LDH samples after regeneration consist of large particles with sharp edges along with a large amount of smaller particles

The aim of this work was to increase our understanding of collagen (COLL)/ hydroxyapatite (HA) composite materials; more specifically, we focused on the study of the influence of the precursorconcentrations over the final content of deposited HA. We found that the increase of the precursor concentrations led to better mineralization (on the basis of the content of deposited mineral phase). Regardless of the precursor concentrations, the content of the deposited amount was found to increase with the increase of the number of deposited layers. Quantification of the mineral phase amount was achieved by gravimetric determination. Based on the determined deposition equation the number of layers can be easily determined in order to obtain composite materials with desired content of mineral phase.

Results on the influence of mechanoactivation (3–30 min) in a planetary ball mill on the composition, crystal structure, IR spectra and morphology of EuCl3·6H2O, dibenzoylmethane (HDBM) and mixtures of EuCl3·6H2O — HDBM and EuCl3·6H2O — HDBM — 1,10-phenathroline (phen) are presented. Mechanoactivation leads to a decrease of interplanar distances of the EuCl3·6H2O and HDBM and partial synthesis of Eu(DBM)3 and Eu(DBM)3·phen in the respective mixtures. The fluorescence properties of the products of activation (excitation and emission spectra, lifetime of the excited states) are similar to those of the complexes produced by the conventional “wet” methods, but the strongest excitation of the mechanochemically produced solid state samples is achieved at higher wavelength. Crystals of different forms (prismatic, needle-, long-length-leaf- and rod-like) are formed by mechanoactivation of the mentioned mixtures.

A series of ethoxylates of 2,2,4-trimethyl-1,3-pentanediol mono-isobutyrate representing a synthetic C12 hydroxyester hydrophobe was obtained. The solubility parameters, surface tension and critical micelle concentrations for model solutions were investigated. The new surfactants were found to produce extremely low foam levels and a non-standard surface interfacial behavior was determined. It was observed that the ethoxylates of the C12 hydroxyester formed an oriented monolayer at the interface regardless of their average polyaddition degree. Such behavior is different from the surface activities of commonly known linear nonionic surfactants and it indicates self organization of the surfactants at the interface. This feature offers possibility for application of these surfactants in nanotechnology as well as in the conventional cleaning processes.

In years 2006–2010 particulate matter analysis was undertaken for dust samples collected from Gdansk and London area in order to compare their morphology and composition. Part of those studies was devoted to analysis of particulate matter (PM) bearing metals. Characterization of the morphology and size of the particles collected onto the filters was performed using a scanning electron microscope (SEM) and transmission electron microscope (TEM). Both electron microscopes were equipped with energy dispersive X-ray spectrometers to identify the elemental composition of the particles. On analysis of the X-ray spectra acquired by both TEM and SEM, the particles were divided into 10 groups as follows: Al-rich, Ba-rich, C-rich, Ca-rich, Cl-rich, Fe-rich, Mg-rich, Na-rich, S-rich, Si-rich. Speciation of the particles based on the major element and accompanying minor elements yielded 34 particle types. However, some pairs of elements repeat, for instance: Na-Cl and Cl-Na, Al-S and S-Al, Si-Al and Al-Si, S-Ca and Ca-S. These are undoubtedly the same types of particles; variation in peak heights of the major and minor elements is normal in a mixed particle population.

This study aims to analyse RDS heavy metal concentrations on road deposited sediment (RDS) using Riccarton Campus of Heriot-Watt University, Edinburgh, Scotland as a study site. RDS samples were collected at two transverse positions from different sites over a 4 month period in order to describe the influence of traffic on heavy metal emissions. The heavy metal concentrations of the RDS were determined by strong nitric acid digestion and atomic absorption spectrometry. The mean concentrations for Zn, Cu, Cd, Cr, Ni, Pb and Fe were found to be 213, 57, 1, 16, 15, 118, and 13497 mg kg-1 from samples near to the curb and 211, 79, 2, 15, 9, 35, and 14276 mg kg−1 from samples 1 m from the curb respectively. Furthermore for both positions the highest concentrations for all metals were associated with the finer fraction (<63 µm) and stronger correlations between the metals were found further from the curb than near the curb, indicating that metals accumulating on the road surface further from the curb may likely be from the same source (traffic), while the sources of metals near the curb are more diverse.

The feasibility of the application of various eluents for recovery of lead and cadmium from Saccharomyces biomass has been investigated. Desorbing agents such as HCl, HNO3, H2SO4, Na2SO4, Na2CO3, EDTA and NaOH at concentrations of 0.05–0.5 M were used. The possibility of re-using of S. pastorianus for cadmium removal was assessed. Among the desorbing agents EDTA and mineral acids were the most effective, as approximately 85% of lead and cadmium could be recovered. However, when HNO3 and EDTA were used as desorbing agents, a dramatic loss in the cadmium adsorption by the biomass in the next cycles was observed.

Metals are perceived as pollutants but they are also natural substances found in the environment. The surface water environment is under the influence of continuing industrial pollution/effluents. Therefore it is necessary to determine various metal forms present in each component of the water ecosystem. The study presents analysis for Cd, Cu, Cr, Fe, Mn, Ni, Zn and Pb content in the Bobrza River bottom deposits and water. The analysis of water and sediment samples from the Bobrza River taken from the littoral zone at three sampling points: the riverhead, i.e. the natural environment; Białogon — the acidic environment; and Sitkówka-Nowiny — the alkaline environment, were analyzed. Sample quality indicators were defined with pH value, conductivity, heavy metal content for water and suspended matter samples. The metal forms in river sediment were also analyzed. The sediment samples were subjected to Tessier’s five-stage sequential extraction procedure assisted by microwave radiation. Analyte concentration in water samples and in the extracts was determined with the use of F-AAS and GF-AAS techniques. The results obtained reveal a relationship between land development, the degree of metal bonding with suspended matter and metal forms found in river sediments.

The relationship between real total contents of the major elements Na, Mg, Al, Si, P, S, K, Ca, Ti, Fe and the trace elements Ag, As, B, Ba, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Sn, V, U, Zn in topsoil from the central part of Vilnius is analysed. The amounts of most elements were determined by energy-dispersive X-ray fluorescence, while amounts of Ag, B, Co were measured by optical atomic emission spectrophotometry. Two factors were distinguished according to major elements: anthropogenic (A) including Ca, Mg, Fe, P, S and clayey (C) including K, Al, Ti. Boron, Mn, Cr and U are significantly correlated with members of both factors, Sb with none of them and other trace elements either with all (Cu, Zn, Pb, Se, Ba, Ni, Co) or with separate (V, Ag, Sn, Mo, As) members of the A-factor. Only B, Mn, Cr, U (partly their additive index Z1) are influenced by the C-factor, while twelve other trace elements (also their additive index Z2) are influenced by the A-factor. The additive index Z of all 17 elements is also affected by the A-factor. Four groups of sites have been distinguished according to normal or higher contents of both factors. The majority of trace element anomalies are related to the sites affected by the A-factor.

Properties of metal solution, environmental conditions and the type of biomaterials (microorganism genus, species or even strain) influence the mechanism of metal biosorption and consequently metal adsorption capacity, affinity and specificity. Cell surface properties determine the metal-microorganism interactions to a large extent. In this work the relationship between yeast surface properties and yeast’s ability to bind cadmium, lead and copper was studied. Surface charge and hydrophobicity before and after biosorption were determined using dye retention and solvent partition assays, respectively. There were differences in the surface charge and relative hydrophobicity among different yeast strains. A higher metal adsorption capacity for more negatively charged yeast cells was observed. Biosorption of heavy metals resulted in modifications to the surface charge and hydrophobicity of yeast cells. However, there were not statistically significant changes in the yeast surface charge and hydrophobicity after binding of heavy metals depending on the nature of the metal, initial metal concentration and solution pH.

The highly sensitive method of adsorptive stripping voltammetry (AdSV), with differential pulse steps, was performed at a mercury film electrode and has been applied here for the determination of trace molybdenum content in selected wild mushrooms. Fruiting body caps of 12 selected macrofungi species from Basidiomycetes have been investigated. Molybdenum content of investigated samples was determined in the range of 0.006 to 0.38 mg kg−1 of dry matter. The highest value of molybdenum content was found in Leccinum rufum and the lowest in Lactarius deliciosus.

The Kielce Lake is a water reservoir located in the Kielce city zone. Areas around the reservoir are used for recreational, residential and industrial purposes. Additionally, the nearby state road to the city of Łódź, is a source of transportation pollution, including heavy metals. The reservoir is fed by a watercourse which receives municipal wastewater from the town of Masłów near Kielce. The amount and diversity of organic and inorganic compounds which flow into the reservoir causes heavy pollution of the Lake waters. To reduce the degree of reservoir pollution, a pulverizing aerator was installed in the middle of the Kielce Lake in May 2008. Sediment samples were collected at a depth of 0–20 cm between July 2008 and May 2010 at five sites in the littoral zone of the recultivation area. These environmental samples underwent a five-stage sequential extraction procedure, assisted by microwave radiation. The concentrations of trace metals Zn, Cu, Ni, Cr, Pb, Mn, Fe and Cd in various extracts were determined by means of F-AAS and GF-AAS. The results have shown a high concentration of analytes in reservoir sediments.