A new type of vanadium-containing ionic liquids (ILs) was synthesized by cation exchange from barium salts of oxidovanadium(IV) complexes stabilized by edta and its congeners (dcta, oedta, and heedta) serving as pentadentate ligands. All starting barium salts and several magnesium and cesium salts, serving as models for the cation exchange, were structurally characterized by single-crystal XRD analysis. The synthesized ILs consisting of organic cations (Bu4N+, Bmim+, and Bu4P+) and complex anions ([VO(edta)]2-, [VO(dcta)]2-, [VO(oedta)]-, and [VO(heedta)]-) were characterized by analytical and spectroscopic methods including EPR spectroscopy and cyclic voltammetry. Then, ILs were tested as catalysts for the ring-opening copolymerization of epoxy resin with cyclic anhydride showing significant catalytic activity, which led to production of highly cross-linked glassy thermosets. A detailed isothermal DSC kinetic study was performed for the most promising IL showing that the progress of cross-linking can be successfully fitted by the Kamal-Sourour model. Based on the DSC and NIR results, the initiation mechanism of the cross-linking in the presence of vanadium-containing IL was suggested. IL had ability to activate a rapid hydrolysis of anhydride cycle and the formed carboxyl groups initiated a polyesterification. In parallel, the role of imidazolium cation of IL for the initiation of chain-growth anionic copolymerization is also discussed.

A series of molybdenum(II) compounds [(η5 -Cp')Mo(CO)2 (L2 )][BF4 ] (Cp'=C5 H4 (CH2 )2 SPh, C9 H6 (CH2 )2 OMe, L2= N,N-chelating ligand) have been synthesized and characterized by spectroscopic and analytical methods including X-ray crystallography. The in vitro assay on human leukemia cells MOLT-4 has shown that the substitution in the π-ligand in combination with suitable N,N-chelating ligand can lead to species with cytotoxicity considerably higher than reported to cisplatin. Unusually high activity was observed for compounds bearing phenanthroline ligands [{η5 -C9 H6 (CH2 )2 OMe}Mo(CO)2 (3,4,7,8-Me4 phen)][BF4 ] (IC50 =0.7±0.3 μM) and [{η5 -C9 H6 (CH2 )2 OMe}Mo(CO)2 (4,7-Ph2 phen)][BF4 ] (IC50 values 0.8±0.4 μM).

Improvised explosives can be, in most cases, prepared from relatively easily accessible matters. The preparation procedure is often simple and generally known, or the information can be looked up on the Internet. The spectrum of phases which can be met concerning these materials is extremely wide and until now no systematic attention has been paid to this fact. In the past years the attention of the Institute of Criminalistics and the University of Pardubice concentrated on preparation of selected groups of these matters, to experimental explosions and to analyses of primary phases and post blast residues using wide spectrum of analytical techniques. Last year the organic analysis was focused on the detection of amines. A simple and sensitive method for the determination of free aliphatic and aromatic amines using derivatives agents as a labelling reagent by high-performance liquid chromatography with fluorescence detection (HPLC-FLD) has been developed. Derivatization conditions including reagent concentration, buffer pH, reaction time and temperature were optimized. A fluorescence derivatization - high-performance liquid chromatography (HPLC) method, which enables the femtomole-level detection of analytes, is a powerful tool for the analysis with high sensitivity and selectivity. Inorganic microanalysis was concentrated on analysis of post-blast residues from experimental explosions of explosive pyrotechnical compositions based on potassium nitrate, sodium nitrate, and barium nitrate – fuel. All the information obtained is stored in a specialized software – database, which will be used by specialized security units. All the activities described above are still in progress.

Každý alkoholický napoj ma sve vlastni aroma a jedinecnou chuť. Elektronický nos (E-nose) je nastroj, který umožňuje analyzovat aroma vzorků. Tato prace ilustruje použiti E-nose pro stanoveni charakteristických vůni sedmi různých alkoholických napojů (bourbon, brandy, koňak, vodka, likery vyrobene z hrusek a ovocne destilaty vyrobene z citronu). Pro klasifikaci alkoholických napojů byly použity nasledujici chemometricke metody pro analýzu dat: analýza hlavnich komponent (PCA), diskriminacni faktorova analýza (DFA a měkke nezavisle modelovani třidy analogie (SIMCA). Výsledky ukazuji, že chemometricke metody PCA a DFA dovoluji urcit jednotlive skupiny ovocných destilatů, bourbonu, koňaku a brandy, ale je obtižne oddělit body likeru, ginu a vodky. Pouze metoda SIMCA umožnila rozlisit body patřici vsem skupinam bez jakekoli aproximace casti grafů.

A series of six indenyl molybdenum compounds bearing a thiophenyl function in the side chain were prepared and characterized by analytical and spectroscopic methods. The structures of [(η5-C9H6CH2C4H3S)(η3-C3H5)Mo(CO)2] and [(η5-C9H6CH2C4H3S)Mo(CO)2(bpy)][BF4] were determined by single-crystal X-ray diffraction. The compounds bearing N,N-chelating ligands exhibit increased cytotoxic activity against human leukemia cell lines MOLT-4; up to two orders of magnitude lower IC50 values were observed compared to analogues with unsubstituted indenyl, which clearly demonstrates the strong effect of the indenyl ligand modification on the biological activity of the molybdenum(ii) compounds. The highest cytostatic potential was observed for the complex bearing 4,7-diphenyl-1,10-phenanthtoline [(η5-C9H6CH2C4H3S)Mo(CO)2(Ph2phen)][BF4] with IC50 (MOLT-4) = 0.19 ± 0.02 μM. Detailed regulation of the molecular and cellular mechanism by this derivative was investigated on the lung carcinoma cell line A549 and compared with the lung fibroblast cell line MRC-5. Rather unusual differences in the effects on tumor and non-tumor cell lines provide a unique insight into the cytostatic action of molybdenum(ii) complexes.

Non-standard and homemade explosives can represent a certain risk for security units as the result of their, practically, unlimited variability both in content and in the construction of explosive objects. Identification of matters that have already gone through an explosion can be problematic. The number of different combinations is really high and it is not difficult to obtain precise and functional instructions for production and the construction itself is quite easy. That is why a few-years-long project was commenced the aim of which is to obtain new complex analytical data of improvised explosives residues. A whole range of experimental substances was selected for experiments including liquid explosives that can be prepared fast and easily. Experimental explosions are carried out on a freshly ploughed soil of dumps of open pit mines (where explosives are not used for mining) to avoid possible contamination. After the explosion, the residues from the stub are analyzed in a standard way and a complex analysis of both organic and inorganic phase is carried out. For selected non-stoichiometric mixtures, explosion characteristics are further calculated unless they are already known. Analysis of post-blast residues of non-standard and homemade compounds is usually started with the SEM analysis. Concerning the character of the data obtained in the frameworks of the project, a special information system is programmed. All the data obtained are entered into this system. The information system is a database layer allowing data to be entered, classified and analysed. The system shall serve the Forensic Laboratories and Expert Services of the Police of the Czech Republic and other specialized units.

Head-space solid phase microextraction (HS-SPME), simultaneous distillation-extraction (SDE) and supercritical fluid extraction (SFE) were employed to prepare volatile extracts of tonka beans (Dipteryx odorata). A total of 190 compounds were assigned by gas chromatography/mass spectrometry (GC/MS) together in comparison with retention indices. These included 156 (HS-SPME), 77 (SDE) and 36 (SFE) compounds (alcohols, carbonyl compounds, acids, esters, terpenes, terpenoids, lactones, aliphatic and aromatic hydrocarbons, and other non-categorised compounds). Semiquantitative evaluation of individual compounds was performed using gas chromatography coupled with a flame ionisation detector. The main constituent detected in all extracts was coumarin (51-85%, despite the extraction method) belonging to the group of lactones. A comparison was made among the three methods in terms of volatile profiles, categorisation of compounds and representation of individual groups of compounds. Extracts prepared by HS-SPME were rich in alcohols, carbonyls and acids than other extracts. Results can provide essential information for the application of different treatment of tonka beans in flavor industries.

V praci je popsan vývoj metody pro stanoveni alifatických aminů pomoci kapalinove chromatografie s využitim citlive fluorescencni detekce. Je zde popsan způsob derivatizece. Nalezene podminky byly testovany na realných vzorcich, ktere byly ziskany po odpaleni namichaných směsi.

Fruit spirits are typical alcoholic beverages in the Moravian region of the Czech Republic. The aim of this work was to find differences in chemical composition among volatile profiles of spirits produced from various kinds of fruits. Twenty-four samples of seven kinds of fruit spirits (plum, apple, pear, cherry, mirabelle, apricot and raspberry spirits) were analysed for examination of their volatile profiles. The most abundant family of compounds was esters, particularly ethyl esters. Sesquiterpenes proved to be a significant group of volatile substances by observing the differences between pome and stone fruit spirits [by relative higher content of (E,E)-a-famesene and by presence of alpha-zingiberene and (E)-alpha-bisabolene in volatile profiles of pome fruit spirits]. Only in stone fruit spirits were propyl decanoate and ethyl salicylate found. Some other compounds were observed as being characteristic for individual kinds of analysed fruit spirits, e.g. gamma-decalactone for apricot spirits, (E)-beta-farnesene for apple spirits, (Z)-9-tetradecen-1-ol for mirabelle spirits or some apocarotenoids for raspberry spirits. This work could potentially be the basis for checking the fruit origin of these distillates, or a partial manual as to how to differentiate individual kinds of pome-fruit spirits (pear and apple spirits) or stone-fruit spirits (plum, mirabelle, apricot spirits). (C) 2017 The Institute of Brewing & Distilling

This study is focused on the optimisation of stir-bar sorptive extraction method for isolation of volatile sulphur compounds of garlic followed by gas chromatography coupled with electron impact detector analysis. By the Plackett-Burmanův design the significant experimental parameters affecting the extraction process were evaluated and these parameters were then optimised by central composite design principles.

Two ultrasonic systems were compared with different settings for extraction of capsaicinoids (capsaicin, dihydrocapsaicin and nordihydrocapsaicin) from chili peppers. The first system was ultrasonic homogenizer using an ultrasonic probe operating at a working frequency of 20 kHz, with variable setting of power output. The second one was ultrasonic cleaner operating at a working frequency of 35kHz, with fixed power output of 50 W. Determination of the optimum extraction procedures was performed by comparison of the extraction yields. Content of capsaicinoids was determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS). Optimization studies of extractions by both ultrasonic systems were performed. Ten various real samples of chili underwent optimum extraction conditions in both ultrasonic systems. The results were compared with each other and to a conventional Soxhlet extraction. The ultrasonic methods provide the higher extraction efficiency and simple and straightforward operation. System working at higher power of ultrasound resulted in higher extraction yields. An application of ultrasonic system working at lower frequency of ultrasonic waves is slightly advantageous.

A series of the cyclopentadienyl and indenyl molybdenum compounds bearing alkylammonium functions [(eta(5)-Cp')Mo(CO)(2)(L-N,L-N)][BF4](2) were synthesized and characterized by analytical and spectroscopic methods. The structures of [{eta(5)-C5H4CH2CH2NH(CH2)(5)}Mo(CO)(2)(4,7-Ph-2-phen)][BF4](2) (4,7-Ph-2-phen = 4,7-dipheny1-1,10-phenanthroline) and [(eta(5)-C9H6CH2CH2NHMe2)Mo(CO)(2)(phen)][BF4](2) (phen = 1,10-phenanthroline) were determined by X-ray crystallography. All of the synthesized compounds exhibit high activity against the human leukemia cell lines MOLT-4 and HL-60. They are approximately one order of magnitude more active than cisplatin. This study has proven that the modification of the outer coordination sphere of molybdenum complexes has a strong impact on their activity and may be successfully used for the design of new highly cytotoxic active species.

An alcohol dehydrogenase-based biosensor was prepared and tested for its use to determine ethanol in beer. The biosensor is based on a screen-printed carbon electrode (SPCE) modified by rhodium dioxide and immobilized with a biocatalytic layer containing the enzyme. Function of the enzyme biosensor was tested in model ethanol samples, in which it showed a linear range of 15–120 g∙L−1 with a detection limit of 3.3 g∙L−1 (established as 3σ) and response time of 19 s. In a potential window from –0.2 to +0.45 V, interferences of both ascorbic and uric acids were negligible. Several types of marketed beers of Czech provenance were selected and subjected to measurements under optimized conditions but without any pretreatment of real samples. When compared with the reference method (gas chromatography), the results were in quite good agreement for beers of the pale lager type but higher contents of ethanol were indicated in the samples of dark lager beers.

In this study, an optimisation of extraction of sulphur volatile compounds (SVCs) has been performed using Central Composite Design. The conditions of the highest amount of eluated peaks and total peaks area have been treated. Factors such as coating of fiber for SPME (Solid Phase Microextraction), extraction temperature and extraction time have been optimised. The SVCs have shown the optimal extraction using a DVB/CAR/PDMS (divinylbenzene/carboxen/polydimethylsiloxane) fiber at 73 °C during 50 min. Furthermore, a pre-incubation step lasting 20 min at the extraction temperature has been used. In total, 12 samples have been investigated at the mentioned optimal conditions, eight from the Alliaceae and four from the Brassicaceae family. The highest number of SVCs (24) has been identified in the sample of chive. The most frequently identified compound found in 11 of 12 samples has been dimethyl trisulphide.

Pressurised hot water extraction (PHWE) was applied to chilies in order to optimise extraction yield of capsaicinoids (capsaicin, dihydrocapsaicin, nordihydrocapsaicin, nonivamide). Determination of the optimum extraction procedure was performed by comparison of the yield of the extracts. Capsaicinoids content was determined by HPLC coupled with mass spectrometry. An optimisation study was performed using water as an extraction solvent at constant extraction pressure (20 MPa), extraction temperature ranging from 120 to 240 degrees C and static extraction time ranging from 5 to 60 min as independent variables. The optimum PHWE conditions for all response variables were estimated; however, PHWE conditions resulting in the highest recovery of capsaicinoids (20 MPa, 200 degrees C and 10 + 20 min of static extraction time) were chosen for comparison with a conventional Soxhlet extraction (SOX) in the case of seven chili pepper fruit samples (chili peppers of species Capsicum chinenses: Trinidad Scorpion Moruga, Jamaican Hot Red, and Yellow Habanero, chilies of species Capsicum annuum: Yellow Bedder, Ring of Fire, and Chiltepin, chili pepper Tabasco of species Capsicum frutescens) and three chili spices (ground spices from Trinidad Scorpion Moruga, Bhut Jolokia, and Fatalii Red, all of species Capsicum chinenses). (C) 2015 Elsevier Inc. All rights reserved.

Extensive traditional use of medical plants leads to research dealing with chemical composition of essential oils. The aim of this work was evaluation of quality of the essential oil and extending of the knowledge about chemical composition of essential oil from ribwort (Plantago lanceolata L.) and proportional representation of compounds. Extractions of essential oils from samples of ribwort were performed by hydrodistillation. GC-MS and GC-FID techniques were used for investigation of the qualitative and semi-quantitative content of aromatic compounds in the essential oils, respectively. Major aroma constituents of ribwort leaves were groups of fatty acids 28.0-52.1 % (the most abundant palmitic acid 15.3-32.0 %), oxidated monoterpenes 4.3-13.2 % (linalool 2.7-3.5 %), aldehydes and ketones 6.9-10.0 % (pentyl vinyl ketone 2.0-3.4 %) and alcohols 3.8-9.2 % (1-octen-3-ol 2.4-8.2 %). In relative high amount were identified apocarotenoids (1.5-2.3 %) which are important constituents because of their intense fragrant. The importance is in potential manufacture control of feedstocks before producing of food supplements.

Reaction of Cp2VCl2 with α-amino acids bearing functional group in the side chain gives N,O-chelate complexes [Cp2V(N,O-aa)]Cl (aa=ser, thr, asp, glu, asn, gln, lys, arg). These complexes were studied by spectroscopic methods (ESR, IR and Raman). All prepared complexes contain amino acid ligand bonded via oxygen atom of carboxylic group and nitrogen atom of amino group in α-position giving five-membered chelate ring. We have observed that hydroxy, amine, carboxylic, amide and guanidinium groups present in α-amino acid ligand are not able to coordinate to the central vanadium atom.

In this study a rapid and easily applicable method for the quantification of 2-ethylhexyl nitrate (2-EHN) in diesel fuel was developed and validated. This method employees Fourier transform infrared spectrometry with attenuated total reflectance (ATR-FTIR). Before the determination of 2-EHN content, could be made to be necessary to analyse the fatty acid methyl esters (FAME) content in diesel fuel in order to prepare the appropriate background solution. Based on the matrix assisted calibration method, the limit of detection was found to be 0.009% w/w for 2-EHN and the limit of quantification 0.025% w/w. The method is linear over the range 0.025-0.300% (w/w), with a correlation coefficient over 0.9998 with satisfactory accuracy, repeatability, and reproducibility. The ATR-FTIR method has been applied to quantify 2-EHN in ten samples of real diesel fuel. Relative standard deviations for all fuel samples were lower than 10%. (C) 2013 Elsevier Ltd. All rights reserved.