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Four sets of samples of anodically prepared ZnO thin films were tested as potential photocatalysts for degradation of methyl orange (MO). The results show that the best properties belong to the samples prepared by anodization in oxalic acid and subsequently annealed 3 hours at 341°C. The dependences of the rate of the reaction on the time of use of the photocatalyst, the temperature of the decomposition reaction, the pH of the solution and the illumination were investigated too. The activation energies of the reactions were derived from the dependence of the rate of the reaction on the temperature. The properties of the acquired ZnO anodic films, as well as their compositions and structures were investigated by various analytical techniques, as follows: Attenuated Total Reflection Fourier Transformation Infrared Spectroscopy (ATR-FTIR), X-ray Diffractometry (XRD), Atomic Force Microscopy (AFM), Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP-OES), Scanning Electron Microscopy (SEM) and UV-VIS Spectrophotometry. [ABSTRACT FROM AUTHOR]

In the present study series of triazole-, thiadiazole- and thiosemicarbazone-benzimidazole hybrid compounds were synthesized as potential anti-cancer agents. In order to determine their antitumor potential and cytotoxic effect (via MTT assay) lung adenocarcinoma (A549) and breast cancer (MDA-MB-231) cell lines were examined. For detection of apoptosis induced by drug treatment, DAPI staining was performed in order to observe the apoptotic alterations in cell nuclei. It was found that the thiadiazole derivative 12 leads to the occurrence of micronuclei, suggesting genotoxic effect. Furthermore, a wound healing assay was performed in order to test whether any changes in cell motility occurred upon treatment with the newly synthesized hybrids, since both cell lines are examples of highly invasive tumours. The cell motility of MDA-MB-231 was impeded mostly by compound 12 (15 % of wound closure) and in A549 compound 9 reduced cell motility by 46 % compared to the control. The obtained results suggest that compound 12 possesses a promising anticancer effect. [ABSTRACT FROM AUTHOR]

New 1,3-disubsituted benzimidazol-2-ones are synthesized in order to evaluate their anti-trichinellosis efficacy. Solid-liquid phase transfer catalysis as the most readily available synthesis method was used to prepare the target compounds. The precursors required for the synthesis of the disubstituted benzimidazoles were obtained by means of two methods. Structures analysis of the compounds by means of IR, 1H NMR analysis was performed. The molecular geometry and electron structure of these molecules were evaluated using density functional theory (DFT) methods. Antitricinellosis activity of the compounds was investigated. The parasitological study in vitro showed that some of the tested benzimidazolones possessed higher activity against Trichinella spiralis than albendazole. The data of SAR for most of the tested compounds are comparable with those of albendazole. [ABSTRACT FROM AUTHOR]

This is the first report on the synthesis of vitamin B9-Rapana thomasiana hemocyanin conjugates (vit. B9-RtH). Proteins modified with 25 and 150 vitamin B9 residues аre obtained in a coupling reaction between N-hydroxysuccinimide-activated γ -carboxylic groups of vitamin B9 and the amino-groups of N-terminal amino acids and lysines comprising the protein. ATR-FTIR spectroscopy is applied to monitor the changes of the secondary structure upon the modification. The comparison of the secondary structure of the native and the vitamin B9-conjugated RtHs shows that the modification results in an increase of the β-structures in a favor of α-helices and coiled structures. The therrmal stability of the novel preparations is evaluated by differential scanning calorimetry (DSC). Despite the serious changes of the conformation, the vit.-B9-RtH conjugates are characterized by a high thermal stability. It is assumed that the changes of the DSC profiles are due to alternative protein-protein interactions, e.g H-bonding, stacking or hydrophobic interactions with vitamin B9 moieties that are possible in the modified RtH molecules. [ABSTRACT FROM AUTHOR]