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Wyniki wyszukiwania dla: equine urine samples
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Ionic liquids in extraction techniques: Determination of pesticides in food and environmental samples
PublikacjaThe intensive use of pesticides in agricultural practices has promoted the appearance of environmentaland public health problems. Due to that, scientists face challenges with developing simple, fast, sensitive,selective, and low-cost methods dedicated to determining pesticide residues in food and environmentalsamples. Following thefifth principle of Green Analytical Chemistry, chemists are searching for greeneralternatives for...
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Comparison of different extraction techniques of polychlorinated biphenyls from sediments samples.
PublikacjaIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. Main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sedimentreference material (METRANAL 2) with the use of different solvents (dichloromethane, hexsane, and toluene); the process...
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New achievements in the field of extraction of trace analytes from samples characterized by complex composition of the matrix
PublikacjaWithout any doubt, the monitoring of compounds present in samples at trace or ultra-trace level usually requires a preliminary step of isolation and/or enrichment of analytes due to the fact that majority of analytical techniques are not sensitive enough for direct determination of trace compounds. On the other hand, sample preparation is considered as crucial part of whole analytical procedures, in particular in samples characterized...
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‘Green’ multi - residue methods for the determination of high importance currently used pesticides in environmental samples
PublikacjaThe purpose of the research has been to develop and apply ‘green’ analytical methodologies to control and monitor the level of currently used pesticides from different chemical groups in aqueous samples. For extraction of analytes solid - phase microextraction (SPME) and dispersive liquid - liquid microextraction (DLLME) have been applied and compared. For SPME, commonly used materials for coating fibers include: polydimethylsiloxane...
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Long-Term Stability of Benzodiazepines and Z-Hypnotic Drugs in Blood Samples Stored at Varying Temperatures
PublikacjaBenzodiazepines (BZDs) and Z-drugs are among the most commonly prescribed pharmaceuticals in the world and are considered standard care for various mental illnesses and for treatment of sleeping and anxiety disorders, alcohol withdrawal, muscle spasms and epilepsy. Some BZDs are not allowed as pharmaceuticals in many countries, and they are used as "designer benzodiazepines" (DBZDs). All these compounds are typically screened in...
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Environmental Phage-Based Cocktail and Antibiotic Combination Effects onAcinetobacter baumanniiBiofilm in a Human Urine Model
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Comparison of Fluoride Ion-Selective Electrode Based Potentiometric Methods of Fluoride Determination in Human Urine
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GC-MS-based untargeted metabolomics of plasma and urine to evaluate metabolic changes in prostate cancer
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Comparison of RP-HPLC columns used for determination of nucleoside metabolic patterns in urine of cancer patients
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A targeted metabolomic protocol for quantitative analysis of volatile organic compounds in urine of children with celiac disease
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Organomercury compounds in environmental samples: emission sources, toxicity, environmental fate and determination.
PublikacjaIn view of the specific properties of mercury and its capability of forming compounds that can be bioaccumulated and biomagnified at successive levels of the trophic pyramid, it has become necessary to gather detailed information on the sources of emission of this element into the environment and its fate there. Moreover, the increasing awareness of the relationship between the toxicity of mercury and its chemical form has sharpened...
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The use of selected analytical techniques for pollutants determination in the environmental samples collected from the Arctic regions
PublikacjaThe paper concern importance of the use of analytical techniques for pollutants determination in the Arctic based on the example of total organic carbon, phenolsandformaldehyde determinationandmeasurementofpHand electrical conductivity parameters in surfacewater samples collected fromthe Revelva catchment.
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Application of GC-MS/MS technique for the determination of benzodiazepines in blood samples
PublikacjaAbstract Benzodiazepines (BZD) are widely used as pharmaceuticals in medicine. However, due to psychostimulatory effect of BZD, in the last decade, they are more and more often used as drugs of abuse. These compounds produce similar effects to classical illicit drugs and are sold as “legal” alternatives to them as new psychoactive substances (NPS). Currently new BZD, named designer benzodiazepines (DBZD), are synthesized each year...
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SYNTHETIZED MEMBRANES FOR ULTRASOUND-ASSISTED SOLVENT EXTRACTION OF POROUS MEMBRANE PACKED SOLID SAMPLES.
PublikacjaMembranes are becoming more and more popular in analytical chemistry, which is why they are used, among others, in extraction processes. Therefore, this work focuses on the process of synthesis PVDF membranes and its optimization. The obtained membranes were used as bags for the phthalate extraction in disposable diapers for babies. Extraction was accomplished by method ultrasound-assisted solvent extraction of porous PVDF membrane...
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Greenness assessment of analytical methods used for antibiotic residues determination in food samples
PublikacjaFood of animal origin plays an important role in ensuring a healthy and sustainable human diet. However, residues of pharmaceuticals, especially antibiotics, can be the cause of many health problems. To protect consumers and improve food quality, analytical methods used to determine contaminants should be simple, selective, and have high throughput and low detection limits. Recently, greenness metric tools have proven useful in...
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New, fast and cheap prediction tests for BRCA1 gene mutations identification in clinical samples.
PublikacjaDespite significant progress in cancer therapy, cancer is still the second cause of mortality in the world. The necessity to make quick therapeutic decisions forces the development of procedures allowing to obtain a reliable result in a quick and unambiguous manner. Currently, detecting predictive mutations, including BRCA1, is the basis for effectively treating advanced breast cancer. Here, we present new insight on gene mutation...
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Determination of selected chemical parameters in surface water samples collected from the Revelva catchment (Hornsund fjord, Svalbard)
PublikacjaSurface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters deter- mination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant...
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Taq DNA polymerase fused with DNA binding protein with increased resistance to inhibitors from clinical samples
PublikacjaNowadays PCR method is commonly used in molecular diagnostic. However, in many cases PCR is limited, by the presence of inhibitory substances in biological, soil or food samples Efficiency and fidelity of amplification is strongly connected with DNA polymerase and reaction conditions. To meet the requirements of modern diagnostic methods it is essential to seeking for new DNA polymerases with better properties useful in these field....
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An analytical hierarchy process for selection of the optimal procedure for resveratrol determination in wine samples
PublikacjaThe study shows the application of analytical hierarchy process (AHP) in ranking the analytical procedures, that are applied for resveratrol determination in wine samples. 19 different analytical methodologies are described by metrological, economic and environmental criteria, that are further divided into 10 subcriteria. Before AHP application, the amount of input data is decreased with cluster analysis. The first run of AHP is...
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Analytics of dew and fog samples - problems and challenges
PublikacjaBadania analityczne próbek mgły i rosy mogą dostarczyć wielu interesujących informacji o stanie powietrza atmosferycznego i procesów, które w nim zachodzą. Badania takie stanowią jednak poważne wyzwanie analityczne m.in. ze względu na: konieczność dysponowania odpowiednimi urządzeniami do pobierania próbek, małe objętości próbek jakie udaje się zebrać w określonym czasie, co w istotnym stopniu determinuje wybór techniki ich przygotowania...
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Strategy of collecting samples from an aquatic environment
PublikacjaW rozdziale opisano strategię, sposoby i urządzenia do pobierania próbek wód powierzchniowych i podziemnych, a także osadów dennych, które stanowią integralną cześć środowiska wodnego. Zwrócono uwagę na aktualne trendy w sposobach pobierania próbek do oznaczania zanieczyszczeń środowiska, szczególnie opartych na metodach pasywnych.
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Preparation of samples for analysis: the key to analytical success
PublikacjaW rozdziale przedstawiono informacje literaturowe o nowych rozwiązaniach metodycznych w zakresie:-izolacji i/lub wzbogacania śladowych składników z próbek środowiskowych-mineralizacji próbek.Szczególna uwagę zwrócono na wykorzystanie w procesie przygotowania próbek nowych typów rozpuszczalników i mediów reakcyjnych spełniających wymogi związane z koncepcją zrównoważonego rozwoju.
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Pesticide analysis of bee and bee product samples
PublikacjaBee products possess therapeutic properties and are the source of many essential trace elements,which is why they are regarded as valuable food products. Honey bees may bring to thehive numerous contaminants deposited on the plants they visit, including pesticide withoutxenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead tomass mortality among bees, and the chemicals find their way into...
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Effectiveness of in-needle extraction device for liquid samples
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Pesticide Analysis of Bee and Bee Product Samples
PublikacjaBee products possess therapeutic properties and are the source of many essential trace elements,which is why they are regarded as valuable food products. Honey bees may bring to thehive numerous contaminants deposited on the plants they visit, including pesticide withoutxenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead tomass mortality among bees, and the chemicals find their way into...
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Preparation of samples of plant material for chromatographic analysis
PublikacjaPrzedstawiono informacje literaturowe nt. etapów przygotowania próbek materiału roślinnego do analizy chromatograficznej. Szczególną uwagę zwrócono na techniki izolacji i/lub wzbogacenie analitów przed etapem oznaczeń końcowych, walidację stosowanych procedur, sposoby pobierania próbek celem określenia emisji biogenicznej lotnych związków organicznych.
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Multivariate Assessment of Procedures for Molecularly Imprinted Polymer Synthesis for Pesticides Determination in Environmental and Agricultural Samples
PublikacjaIn the case of quantitative and qualitative analysis of pesticides in environmental and food samples, it is required to perform a sample pre-treatment process. It allows to minimalize the impact of interferences on the final results, as well as increase the recovery rate. Nowadays, apart from routinely employed sample preparation techniques such as solid-phase extraction (SPE) or solid-phase microextraction (SPME), the application...
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Genetic and biochemical characterization of yeasts isolated from Antarctic soil samples
PublikacjaThe Polish Arctowski Station is situated in the maritime Antarctic on the western shore ot' Admiralty Bay and encompasses terrestrial habitats which are not perma-nently covered by ice, in contrast to morę than 90% of the island's surface area. Over the past several decades, stud-ies exploring the soils of those habitats have revealed a considerable diversity of bacteria, filamentous fungi, and, to a lesser extent, yeasts; however,...
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublikacjaThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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Arctic as a reservoir for polycyclic aromatic hydrocarbons and polychlorinated biphenyls- water samples from Foxfonna glacier
PublikacjaPolycyclic aromatic hydrocarbons and polychlorinated biphenyls are groups of stable compounds, hard to biodegrade, potentially toxic. Their presence in Arctic environment may have a big impact on natural balance, fauna and flora. Although Arctic areas should be unpolluted, some amounts of pollutants are transferred from lower latitudes with sea currents and air masses. This paper presents the amounts of selected persistent organic...
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Identification of organic acids as potential biomarkers in the urine of autistic children using gas chromatography/mass spectrometry
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Serum-to-urine renalase ratio and renalase fractional excretion in healthy adults and chronic kidney disease patients
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Serum-to-urine renalase ratio and its differences between healthy adults and chronic kidney disease patients
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Serum-to-urine renalase ratio and renalase fractional excretion in healthy adults and chronic kidney disease patients.
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Serum-to-urine renalase ratio and renalase fractional excretion in healthy adults and chronic kidney disease patients.
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Serum-to-urine renalase ratio and its differences between healthy adults and chronic kidney disease patients
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A solid phase extraction–ion chromatography with conductivity detection procedure for determining cationic surfactants in surface water samples
PublikacjaA new analytical procedure for the simultaneous determination of individual cationic surfactants (alkyl benzyl dimethyl ammonium chlorides) in surface water samples has been developed. We describe this methodology for the first time: it involves the application of solid phase extraction (SPE – for sample preparation) coupled with ion chromatography–conductivity detection (IC-CD – for the final determination). Mean recoveries of...
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublikacjaDue to human activities, the concentrations of organometallic compounds in all parts of the environment have increased in recent decades. The toxicity and some biochemical properties of mercury and tin present in the environment depend on the concentration and chemical form of these two elements. The ever-increasing demand for determining compounds at very low concentration levels in samples with complex matrices requires...
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Determination of fuel combustion product in airport runoff water samples using liquid–liquid extraction with gas chromatography–spectrometry
PublikacjaDetermination of xenobiotics in samples of airport runoff water is both a complex and indispensable task due to an increasing threat resulting from the activities of numerous airports. The aim of this study was to develop, optimize, and validate a procedure based on liquid–liquid extraction (LLE) coupled with gas chromatography–mass spectrometry (GC–MS) for the determination of polycyclic aromatic hydrocarbons (PAHs). So far, no...
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Chemical pollution and toxicity of water samples from stream receiving leachate from controlled municipal solid waste (MSW) landfill
PublikacjaThe present study was aimed to determine the impact of municipal waste landfill on the pollution level of surface waters, and to investigate whether the choice and number of physical and chemical parameters monitored are sufficient for determining the actual risk related to bioavailability and mobility of contaminants. In 2007–2012, water samples were collected from the stream flowing through the site at two sampling locations,...
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Solventless and solvent-minimized sample preparation techniques for determining currently used pesticides in water samples: A review
PublikacjaThe intensification of agriculture means that increasing amounts of toxic organic and inorganic compounds are entering the environment. The pesticides generally applied nowadays are regarded as some of the most dangerous contaminants of the environment. Their presence in the environment, especially in water, is hazardous because they cause human beings to become more susceptible to disease. For these reasons, it is essential to...
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Determination of hormones in water samples using liquid chromatography coupled with tandem mass spectrometry
PublikacjaOver the past few years, many synthetic (ethinylestradiol) and natural (estradiol,estriol, estrone) compounds present in the environment have been affecting the hormonalbalance of humans and animals. Steroid hormones are very often used for medical purposesand have high estrogenic activity what makes them endocrine disrupters. Most hormonalcompounds are released into the water as a result of their incomplete removal in wastewatertreatment...
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Correlation between chemical composition and the presence of selected groups of bacteria in freshwater samples collected from Isfjorden and Billefjorde
PublikacjaThe average concentrations of pollutants in the arctic water, snow and the atmosphere are much lower than those observed in the temperate climate. Specific conditions occurring in the polar regions have apotential to accumulate the pollutants transported from other parts of the world. In this study, attempts were made to find a correlation between selected chemical components and the bacterial population. The analysis involved...
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LC-MS/MS dtermination of isoprostanes in plasma samples collected from mice exposed to doxorubicin or tert-butyl hydroperoxide
PublikacjaIsoprostanes are stable products of arachidonic acid peroxidation and are regarded as the most reliable markers of oxidative stress in vivo. Here we describe the LC-MS/MS procedure enabling simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in plasma samples collected from mice. The four plasma isoprostanes are determined by LC–ESI-MS/MS...
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Organic Acids and Polyphenols Determination in Polish Wines by Ultrasound-Assisted Solvent Extraction of Porous Membrane-Packed Liquid Samples
PublikacjaIn the near future, Poland is going to have more and more favorable conditions for viticulture. Organic acids and polyphenols are among the most commonly analyzed compounds due to their beneficial properties for human health and their importance in the winemaking process. In this work, a new technique involving ultrasound-assisted solvent extraction of porous membrane-packed liquid samples (UASE-PMLS) was for the first time described...
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Drill holes decrease cancellous bone strength: A comparative study of 33 paired osteoporotic human and 9 paired artificial bone samples
PublikacjaThis study was designed to compare compressive strength of cancellous bone retrieved from the femoral head in a specimen with and without guide wire hole, with comparison to synthetic bone samples. Femoral heads retrieved from 33 patients who sustained femoral neck fractures and underwent hip arthroplasty were cut into cuboids leaving two matching samples from the same femoral head. Similar samples were prepared from synthetic femurs....
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublikacjaIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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Main complications connected with detection, identification and determination of trace organic constituents in complex matrix samples
PublikacjaIt is well known that some problems with the determination of organic analytes at trace level can occur. This issue is connected with contamination during each stage of the analytical procedure from sampling to sample preparation up to chromatographic analysis, which often leads to false-positive or overestimated results. Another problem associated with determination of analytes occurs at trace- and ultra-trace level is a background...
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Sensitive determination of isoprostanes in exhaled breath condensate samples with use of liquid chromatography-tandem mass spectrometry
PublikacjaOxidative stress is the hallmark of various inflammatory lung diseases. Increased concentrations of reactive oxygen species in the lungs are reflected by elevated concentrations of oxidative stress markers in the breath, airways, lung tissue and blood. The aim of this work was to develop a method for the fast measurement of F2 isoprostanes in exhaled breath condensate (EBC) samples using equipment which is nowadays available and...
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Rapid method for the determination of organochlorine pesticides and PCBs in fish muscle samples by microwave-assisted extraction and analysis of extracts by GC-ECD
PublikacjaA procedure for the multiresidue determination of organochlorine pesticides and polychlorinated biphenyls in fish muscle samples has been developed. The method is based on the microwave-assisted extraction (MAE) of food samples from an acetonitrile-water (95 + 5, v/v) mixture followed by SPE cleanup of the extracts and analysis by GC with an electron capture detector. MAE operational parameters, such as the extraction solvent,...