Development and application of hplc-ms/ms method for determination of pesticide traces in water samples

Predmet ovog rada je razvoj, optimizacija, validacija i primena nove, brze i osetljive multirezidualne analitičke metode za određivanje tragova odabranih pesticida, koji pripadaju hemijski različitim grupama, u površinskim, podzemnim i otpadnim vodama. Pri odabiru pesticida prvenstveno je uzeto u obzir koji se najviše koriste u poljoprivrednoj praksi u Srbiji. Prvo je razvijena osetljiva analitička metoda za određivanje odabranih pesticida pomoću tečne hromatografije u sprezi sa tandem masenom spektrometrijom. Posebna pažnja je posvećena optimizaciji metode za pouzdanu maseno-spektrometrijsku detekciju tragova pesticida i razvoju metode potvrde prisustva analita. Zatim je razvijena i optimizovana metoda ekstrakcije na čvrstoj fazi za efikasnu pripremu uzoraka površinskih i podzemnih voda, koja obuhvata istovremenu ekstrakciju i prečišćavanje ekstrakta. Nakon razvoja i validacije metode za pripremu i analizu odabranih pesticida u površinskim i podzemnim vodama, ista je validirana i za uzorke komunalne otpadne vode. Pri validaciji metode određivani su sledeći parametri: prinos, ponovljivost, linearnost, granica detekcije i granica kvantifikacije za sve ispitivane pesticide u svim ispitivanim matricama. Dobre vrednosti prinosa (70%–120%) uz relativnu standardnu devijaciju ± 20% i niske granice detekcije i kvantifikacije postignute su za većinu odabranih pesticida. Potom je razvijena, optimizovana i validirana metoda primenjena na realne uzorke površinskih, podzemnih i otpadnih voda u cilju dobijanja studije o stanju zagađenosti vode najčešće korišćenim pesticidima u našoj zemlji. Istraživanjem je obuhvaćen ceo sliv Dunava u Srbiji sa najvećim pritokama, kao i bunari podzemne vode koji se nalaze u neposrednoj blizini Dunava i pritoka. Uzorci vode prikupljani su u dvanaest kampanja uzorkovanja. Mesta uzorkovanja površinske vode uključivala su poljoprivredna, šumska i gradska područja. Takođe su analizirani i uzorci komunalne otpadne vode Beograda, kao najvećeg grada u našoj zemlji koji bez prethodne obrade otpadne vode direktno ispušta u Dunav i Savu, kao i otpadna voda na ulazu i izlazu iz dva postrojenja za prečišćavanje otpadnih voda. Na osnovu rezultata se može videti uticaj poljoprivrede, i urbane sredine, kao najvećih i najčešćih izvora zagađenja površinskih i podzemnih voda pesticidima.The subject of this thesis is the development, optimization, validation and application of a new, fast and sensitive multiresidual analytical method for determination of selected pesticides, belonging to chemically different groups, in surface and ground water, as well as wastewater. The selection of pesticides was based on their usage in agricultural practice in Serbia. Firstly, sensitive analytical method for the determination of selected pesticides based on liquid chromatography-tandem mass spectrometry was developed. Also, optimization of the method for reliable confirmation of pesticides at trace levels was done. Then, solid-phase extraction method was developed and optimized for efficient preparation of surface and groundwater samples which involves simultaneous extraction and extract purification. Developed and validated method for the sample preparation and analysis of selected pesticides in surface and ground water was validated for municipal wastewater samples. The method was validated for accuracy, reproducibility, linearity, limits of detection and quantification for all investigated pesticides in all tested matrices. Good recoveries (70%–120%) with relative standard deviation ± 20% and low detection and quantification limits have been achieved for the majority of selected pesticides. The developed, optimized and validated method was finally applied to real samples of surface and ground water, as well as wastewater, in order to obtain a study of water contamination with most frequently used pesticides in our country. The study covered the entire Danube basin in Serbia with the largest tributaries, as well as wells of groundwater located near the Danube and tributaries. Water samples were collected in twelve sampling campaigns. Surface water sampling sites included agricultural, forest and urban areas. Municipal wastewater from Belgrade, as the largest city in our country that directly discharges wastewater into the Danube and the Sava without any treatment, was also analyzed, as well as the wastewater at the inlet and the outlet from two wastewater treatment plants. Based on the results, the influence of agriculture and urban environments as the largest and most common sources of pesticide pollution in surface and ground water was determined

Determination of bisphenol A traces in water samples from the Vrbas River and its tributaries, Bosnia and Herzegovina

The bisphenol A (BPA) concentration was determined in 12 surface water samples of the Vrbas River and its five tributaries. The samples were taken in the area that belongs to the city of Banja Luka (Bosnia and Herzegovina). BPA was isolated using micro liquid-liquid extraction followed by derivatization and gas chromatography-mass spectrometry analysis (GC-MS). Silylation was used as a derivatization method to increase volatility and allow the GC-MS determination of BPA. The limits of detection (LOD) and quantification (LOQ), obtained by validating the procedure, were determined at 4 and 10 ng L-1, respectively. The concentrations of BPA were ranged between 33 and 354 ng L-1, and all were above the LOQ value. The lowest amount of BPA was found in the sample collected in the river Vrbas, near Švrakava estuary upstream from the city of Banja Luka. The highest concentration of BPA was recorded at the confluence of the Crkvena and Vrbas rivers, which is located in the city center. This study shows that population and human activity could affect the level of BPA in the environment

Struktura i stereohemija poli-(1-naftilamina) elektrohemijski sintetisanog u neutralnom acetonitrilnom rastvoru

Poly-(1-naphthylamine) films were synthesized potentiodinamically and potentiostatically from 1-naphthylamine in neutral acetonitrile medium using a platinum electrode. These polymer films were investigated by infrared spectroscopy. Contrary to earlier published results neglecting the stereochemistry of the poly-(1-naphthylamine), we predict on the basis of quantum stereochemical analysis of the possible structural subunits of the polymer, that the ordinary N–C(4) coupled product is not predominant in the polymer because it is far removed from the expected planarity. Based on the results of IR investigations and semiempirical quantum chemical calculations, it is proposed that the polymer products are formed via mixed N–C(4), N–C(5) and N–C(7) coupling routes. The heats of formation of the oxidized 1-naphthylamine dimers and hexamers were calculated.Poli-(1-naftilaminski) filmovi sintetisani su potenciostatski i potenciodinamički iz neutralnog acetonitrilnog rastvora 1-naftilamina na platinskoj elektrodi. Ovi polimerni filmovi ispitivani su IR spektroskopijom. Za razliku od ranije publikovanih rezultata koji su zanemarivali stereohemiju poli-1(-naftilamina), u ovom radu se predviđa na osnovu kvantne stereohemijske analize mogućih strukturnih jedinica polimera da uobičajeni N–C(4) kuplovani produkt nije predominantan u polimeru, jer njegova struktura nije planarna. Na osnovu rezultata IR ispitivanja i semiempirijskih kvantno-hemijskih proračuna mi pretpostavljeno je da se polimerni produkti formiraju kombinovanim N–C(4), N–C(5) i N–C(7) načinima vezivanja 1-naftilamina. U ovom radu su takođe izračunate toplote nastajanja oksidovanih dimera i heksamera 1-naftilamina

Position and size of massa intermedia in Serbian brains

Background: Massa intermedia, a midline bar-shaped structure, connects two thalami across the third ventricle in 70–80% of healthy humans. It has become clinically important since its absence was comprehended as a midline malformation of the brain and brought in connection with schizophrenia indicating that some symptoms could be a consequence of disturbed neuron chains underlying the mechanisms of attention and processing of information. The aim of the investigation was to find out the incidence, position, and size of massa intermedia in the brains of the Serbian population. Materials and methods: Our investigation was performed on 41 brains of adult Serbian cadavers using a macro dissection method. Results: Massa intermedia was present in 80.49% of cases, in 1 case it was double. In most of the cases it was located in the superior quadrants of the lateral wall of the third ventricle, the larger part being in the anterosuperior one. Some other combinations were also present. The horizontal diameter of the cross-section was larger than vertical and was not in correlation with the length of the third ventricle. The average cross-sectional area was 29.58 mm2, significantly larger in females. Conclusions: Massa intermedia is present in most of the investigated brains, usually connecting the anterior-superior quadrants of the lateral walls of the third ventricle. Different in shape and size its cross-section is a horizontal ellipse, significantly larger in females. The cross-sectional area and the size of the third ventricle are not in correlation

The Response of Badland Materials from Spain with Different Mineralogical Content on Seasonal Changes

Badlands are areas with limited vegetation, reduced or no human activity, and a great variety of geomorphic processes [1]. Badland materials have a different responsetothe same environmental conditions, because of differences in their mineralogical and physico-chemical characteristics. Many studies show that smectite-poorsediments are more resistant to different weathering treatments of freezing, thawing, wetting, and drying,than smectite-rich materials [2,3].In this paper, three unweathered samples of badlands from Spain were analyzed with the aim of monitoring, but also comparing physico-chemical changes caused by simulations of changes in climatic conditions. Selectedsediment samples havedifferent compositions. Besides quartz and calcite, the first sampleis composed of smectite and gypsum (3 UW), the second of smectite (4 UW), while the third sample is composed of neither smectite nor gypsum (5 UW). The experiment setup was designed in the way that each sample had three sub-samples, a sample for simulation of rain, snow, and a control sample (Figure 1). Sample_rain was treated with a rain intensity of ~850 ml/h for 10 minutes (~140 ml), while sample_snow was treated with crushed ice (~150 g). After precipitation simulations snow were put samples were placed in a climate chamber at - 3 °C together with a control sample. This was repeated for 15 cycles. Every cycle was documented with photographs. The leached solution was collected and its volume, pH, electrical conductivity (EC), and ion concentrations were measured. The second part of the experiment was based on exposing the samples after wetting to higher temperatures, 50 ° C. It was done in 8 cycles. FESEM and BET analyzes were performed for each sample before and after the experiments.The 3 UW samples had significantly different leachate pH and EC, while the leachate volume was similar for all samples during the experiment. Sulphate ions were leached in the highest concentrations during the whole experiment from the sample with both smectite and gypsum present. The sample with smectite has shown the highest disintegration of the structure, especially after the simulation of snow. The sample with smectite and gypsum has shown a lower degree of degradation than sample 3 UW due to the content of gypsum which increases the weathering resistance of the material. Sample 5 UW has shown the lowest degradation of the structure along with the weathering cycles. This study has proven that both mineralogical and physico-chemical properties of sediments are important for predicting their response to variable climate factors

Contamination, risk, and source apportionment of potentially toxic microelements in river sediments and soil after extreme flooding in the Kolubara River catchment in Western Serbia

Climate change is contributing to an increase in extreme weather events. This results in a higher river flooding risk, causing a series of environmental disturbances, including potential contamination of agricultural soil. In Serbia, the catastrophic floods of 2014 affected six river basins, including the Kolubara River Basin, as one of the larger sub-catchments of the large regional Sava River Basin, which is characterized by large areas under agricultural cultures, various geological substrates, and different types of industrial pollution. The main aim of this study was to establish the sources of potentially toxic elements in soil and flood sediments and the effect of the flood on their concentrations. Field sampling was performed immediately after water had receded from the flooded area in May 2014. In total, 36 soil samples and 28 flood sediment samples were collected. After acid digestion (HNO3), concentrations of the most frequent potentially toxic elements (PTE) in agricultural production (As, Cd, Cr, Cu, Ni, Pb, Zn) and Co which are closely related to the geological characteristics of river catchments, were analyzed. The origin, source, and interrelations of microelements, as well as BACKGROUND: values of the PTE of the river catchment, the pollution index (Pi), enrichment factor (Ef), and geological index (Igeo), were determined, using statistical methods such as Pearson correlations, principal component analysis (PCA), and multiple linear regression (MLRA). The content of the hot acid-extractable forms of the elements, PCA, and MLRA revealed a heavy geological influence on microelement content, especially on Ni, Cr, and Co, while an anthropogenic influence was observed for Cu, Zn, and Cd content. This mixed impact was primarily related to mines and their impact on As and Pb content. The pseudo-total concentrations of all the analyzed elements did not prove to be a danger in the catchment area, except for Cu in some samples, indicating point-source pollution, and Ni, whose pseudo-total content could be a limiting factor in agricultural production. For the Ef, the Ni content in 59% soil and 68% flood sediment samples is classified into influence classes. The similar pseudo-total contents of the elements studied in soil samples and flood sediment and their origin indicate that the long-term soil formation process is subject to periodic flooding in the Kolubara River Basin without any significant changes taking place. This implies that floods are not an endangering factor in terms of the contamination of soil by potentially toxic elements in the explored area

Psychotherapy in Europe

Psychotherapy was an invention of European modernity, but as the 20th century unfolded, and we trace how it crossed national and continental borders, its goals and the particular techniques by which it operated become harder to pin down. This introduction briefly draws together the historical literature on psychotherapy in Europe, asking comparative questions about the role of location and culture, and networks of transmission and transformation. It introduces the six articles in this special issue on Greece, Hungary, Yugoslavia, Russia, Britain and Sweden as well as its parallel special issue of History of Psychology on ‘Psychotherapy in the Americas’. It traces what these articles tell us about how therapeutic developments were entangled with the dramatic, and often traumatic, political events across the continent: in the wake of the Second World War, the emergence of Communist and authoritarian regimes, the establishment of welfare states and the advance of neoliberalism

Clinical significance of radioimmunoassay (RIA) and immunoradiometric assay (IRMA) in endocrinology

Radiopharmaceuticals are compounds used in human medicine for the diagnosis of 95% and therapy of 5%. Radiopharmaceuticals are used by in-vivo and in-vitro in medicine. In-vitro application includes RIA methods (radioimmunoassay) in clinical laboratories. RIA methods are methods with bookmarks, i.e. the indicator molecule is marked with a radioactive isotope 125J with a half-life of 60 days. RIA methods are the most sensitive quantitative and qualitative techniques. A radioimmunoassay (RIA) is an immunoassay that uses radiolabeled molecules in a stepwise formation of immune complexes. Immunoradiometric assay (IRMA) is an assay that uses radiolabeled antibodies. It differs from conventional RIA n that the compound to be measured combines immediately with the radiolabeled antibodies, rather than displacing another antigen by degrees over some period. RIA and IRMA are the most commonly used techniques which allow the measurement of a wide range of materials of clinical and biological importance, especially in endocrinology for estimation of hormones. These techniques have a significant impact on medical diagnosis due to the ease with which the tests can be carried out, while assuring precision, specificity and sensitivity. These techniques achieve sensitivity through the use of radionuclides and specificity that is uniquely associated with immunochemical reactions. They are largely used for measuring biologically active compounds present in low concentrations, such as hormones, proteins, drugs, microorganisms, etc. The radioimmunoassay (RIA) method is employed to determine numerous hormones, enzymes, antigens, and drugs in very low quantities (10-12–10-9 M) in human plasma in order to assess various diseases. In RIA, the immunologic reaction between the antigen and the antibody is highly specific, and hence the method has high specificity. The accuracy of the method depends on various experimental factors and the specificity of the antigen–antibody reaction. The precision of RIA is affected by experimental errors in pipetting of reagents, chemical separation of the complex, and counting. IRMA is much more sensitive to RIA, which in some cases (e.g. in TSH) is very significant. Because of the use of monoclonal antibodies in the first phase of the reaction, this system has a much better specificity, which significantly reduces errors due to cross-reactions with other hormones.VII International Conference on Radiation in Various Fields of Research : RAD 2019 : book of abstracts; June 10-14, 2019; Herceg Novi, Montenegr