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Search results for: PRE-ANALYTICAL ASPECTS
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Birds' feathers – Suitable samples for determination of environmental pollutants
PublicationThe intensive development of industry and human population results in large amounts of different xenobiotic emitted into individual ecosystem components. As a consequence, monitoring of the level of pollution of particular elements of the environment by exotoxins has become a common interest. The determination of environmental changes by different types of biological indicators is called bioindication, which is used as one of the...
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Determination of eight artificial sweeteners and common Stevia rebaudiana glycosides in non-alcoholic and alcoholic beverages by reversed-phase liquid chromatography coupled with tandem mass spectrometry.
PublicationThe method for the determination of acesulfame-K, saccharine, cyclamate, aspartame, sucralose, alitame, neohesperidin dihydrochalcone, neotame and five common steviol glycosides (rebaudioside A, rebaudioside C, steviol, steviolbioside and stevioside) in soft and alcoholic beverages was developed using high-performance liquid chromatography and tandem mass spectrometry with electrospray ionisation (HPLC-ESI-MS/MS). To the best of...
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How to evaluate methods used in chemical laboratories in terms of the total chemical risk? – a ChlorTox Scale
PublicationReliable assessment of the health and environmental risk associated with the use of chemicals is critical to ob- jectively evaluate the greenness and whiteness of an analytical method. An objective and useful way of risk assessment should take into account all the relevant properties of used substances, their actual amounts needed for application of the method, and quantify the assessment result using a standardized unit. This...
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New matrix-free reference material for ethene in the form of optical fibres
PublicationReference materials are indispensable in the qualitycontrol and quality assurance of analytical measurements. Onenovel approach to the generation of standard gaseous mixturesof toxic, reactive, volatile, labile, and malodorous substancesinvolves thermal decomposition or rearrangement, under definedtemperature conditions, of compounds immobilized, bychemical bonding, on the surface of an appropriate carrier torelease specific amounts...
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Development and validation of an eco-compatible UV–Vis spectrophotometric method for the determination of Cu2+ in aqueous matrices
PublicationCu 2+ are ubiquitous ions in the ecosystem and are responsible of serious environmental pollution. Indeed, the development of sensitive methods for Cu 2+ detection is an urgent demand. In this work, we proposed a new spectrophotometric method for Cu 2+ determination in different water matrices (distilled water, drinking water, wastewater, and river water). The method employs a bio-based organic ligand namely tetrasodium iminodisuccinate...
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Application of deep eutectic solvents in bioanalysis
PublicationThe application of deep eutectic solvents (DESs) is sharply surging as a green alternative to conventional solvents due to their unique properties in terms of simplicity of preparation, designability and low cost. A great deal of attention has been paid to the application of these green solvents in analytical chemistry in recent years, and a lot of interesting work has been reported. This review summarizes the most relevant applications...
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Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1
PublicationSolid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...
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Modern trends in solid phase extraction: New sorbent media
PublicationBased on the recently published literature, this review provides an update of the most important features and application of formats and devices employed in solid phase extraction (SPE). Special attention was paid on new trapping media proposed in SPE prior the chromatography analysis, based on the use of nanostructured materials, including carbon nanomaterials, electrospun nanofibers, dendrimes and magnetic nanoparticles, molecular...
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Novel Desorber for Online Drilling Mud Gas Logging
PublicationThis work presents the construction solution and experimental results of a novel desorber for online drilling mud gas logging. The traditional desorbers use mechanical mixing of the liquid to stimulate transfer of hydrocarbons to the gaseous phase that is further analyzed. The presented approach is based on transfer of hydrocarbons from the liquid to the gas bubbles flowing through it and further gas analysis. The desorber was...
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Modern solutions in the field of microextraction using liquid as a medium of extraction
PublicationThe monitoring of compounds present in samples at trace/ultra-trace level usually requires a preliminary step of isolation and/or enrichment of analytes. Against, sample preparation is considered as crucial part of whole analytical procedures, in particular in samples characterized by complex matrices composition. Several new miniaturized extraction techniques is introduced and extensively applied to different type of samples....
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Dzielnica Reprezentacyjna Gdyni i jej powojenne oraz współczesne interpretacje
PublicationThe concept of the Premiere District in Gdynia was first conceived in the 1920s and from that time on it constantly accompanied the history of the city. It derivated from the idea of creating a symbol of Poland's regaining independence after the first World War and the successful creation of the new port and city on the Baltic coast. As the result of that development, Gdynia was named the maritime capital of Poland and was treated...
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Diagnostyka ultradźwiękowa mostowej belki prefabrykowanej typu T metodą młoteczkową
PublicationZastosowanie prefabrykacji w budowie obiektów mostowych pozwala optymalizować zużycie energii i materiałów i tym samym redukować koszty budowanego obiektu. Prefabrykowane belki sprężone mogą występować jako elementy kablobetonowe wykonywane bezpośrednio na placu budowy lub powstawać w zakładzie prefabrykacji jako elementy strunobetonowe. Elementy prefabrykowane wytwarzane w warunkach przemysłowych muszą spełniać wymagania wysokiej trwałości,...
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Solventless and solvent-minimized sample preparation techniques for determining currently used pesticides in water samples: A review
PublicationThe 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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Recent breakthroughs in the stability testing of pharmaceutical compounds
PublicationPharmaceutical development is mostly focused on the research leading to approval of a new and viable active substance. However, there is a number of old generation compounds that are still being used in contemporary medicinal practice. So that new analytical developments should cover not only the safety of newly developed drug substances, which is obvious, but should also be directed into the search of individual stability issues...
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Isotope-labeled substances in analysis of persistent organicpollutants in environmental samples
PublicationUltratrace analysis of persistent organic pollutants (POPs) in environmental samples requires very sophisticated methods for both sample preparation and instrumental analysis. The complex matrix requires a multi-stage procedure. Each stage is a potential source of error, as a consequence of which the final result of analysis could be a source of misinformation rather than information. The individual stages and the procedure as...
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Detection, identification and determination of chiral pharmaceutical residues in wastewater: Problems and challenges
PublicationChiral pharmaceuticals (CPs) are widely used in different areas of human life, thus they are frequentlydetected in different ecosystems. However, before CPs reach the environment, wastewater is subjected todifferent treatment processes in order to remove them. Nevertheless, such processes may affect thechirality of CPs, thus it is very important to monitor CP levels during the wastewater treatment.This review addresses the present...
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Analysis of arsenic species in environmental samples
PublicationMany analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas...
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Detection, identification and determination of resveratrol in wine. Problems and challenges
PublicationResveratrol is a compound synthesized by plants in response to unfavorable conditions of growth like mechanical injury, siege of bacteria or fungi and UV exposure. It is concentrated mostly in grapes skin and further more in the products made from grapes especially red wines. Each wine is characterized by different amount of given stilbene since its occurrence is affected by many factors like: types of grapes, environment (climate,...
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Determination and identification of organic acids in wine samples. Problems and challenges.
PublicationFor long time, organic acids were underestimated. However, during last two decades there is an increasing interest of natural compounds having antioxidant, antimicrobial and anti-inflammatory properties thus organic acids are very preferable. Wine stands as one of the sources of organic acids since they are responsible for its organoleptic and aestethic character. Nevertheless, it is important to not exceed acceptable level of...
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Surfactants application in sample preparation techniques: Insights, trends, and perspectives
PublicationSince the implementation of Green Chemistry into analytical practice, significant efforts have been made to improve the sustainability of chemical analysis. These include reducing the use of hazardous chemicals and solvents, minimizing waste, and improving energy efficiency. Surfactants can be applied in chemical analysis as an environmentally friendly alternative to conventional solvents and chemicals. The use of surfactants can...
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Miniaturized solid phase extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 2
PublicationDetermination of pollutants present in environmental samples at a low concentration level very often requires the analytical protocol that includes analytes isolation and/or enrichment prior to the final quantification. Miniaturized SPE offers an interesting alternative to LLE. Nowadays, many types of sorbents are available and can be used as selective materials for extraction of varied analytes in different kinds of samples. The...
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Determination of chlorinated solvents in industrial water and wastewater by DAI- GC-ECD
PublicationA very simple and quick analytical method, basedon direct aqueous injection, for determination of halogenatedsolvents in refinery water and wastewater, is described.There is a need to determine halogenated solvents in refinerywater streams, because they may originate from severalprocesses. There is also a need to develop methods enablingVOX to be determined in samples containing oil fractions.The method described enables simultaneous...
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Liquid–phase microextraction: A review of reviews
PublicationSample preparation is an important step in chemical analysis. It is generally done to deal with problems associated with the nature of the matrix, low analyte concentrations in real samples or analyte features incompatible with the instrumentation. Classical methods of extraction consume large volumes of hazardous solvents and other reagents and are not in line with the recent emergence of green analytical chemistry. Liquid-phase...
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Meconium analysis as a promising diagnostic tool for monitoring fetal exposure to toxic substances: Recent trends and perspectives
PublicationPrenatal exposure to toxic substances is an important public health problem. Many biological specimens obtained from the fetus or mother are used for biomonitoring. Each material reflects exposure in a specific time period and has different advantages and disadvantages in terms of accuracy, time window of detection and cost/benefit ratio. Recently, meconium has become the matrix of choice in toxicology screening for detecting exposure...
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Application of modern sample-preparation techniques to the determination of chloropropanols in food samples
PublicationChloropropanols are heat-induced food toxicants that recently caused concern among industrial and scientific experts. World and European organizations related to food safety asked researchers to investigate mitigation strategies regarding these contaminants. The essential objective of this project was development of fast analytical methods enabling reliable determination and quantification of 3-monochloropropane-1,2-diol, 2-monochloropropane-1,3-diol...
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Challenges in determination of pesticides from various chemical groups in fruits and vegetables applying QuEChERS method
PublicationPesticides are a large group of compounds with different physical and chemical properties, which place some of them among the most toxic, environmentally stable, and mobile substances. Nevertheless, their number, use, and application are continuously expanding. A consequence of their use is the possible presence of residues in treated food products. To protect consumers from exposure to unacceptable levels of pesticides Maximum...
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Pesticide Analysis of Bee and Bee Product Samples
PublicationBee 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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Determination of aminoglycoside antibiotics: current status and future trends
PublicationThe use of aminoglycoside antibiotics is prevalent in medicine and agriculture. Their overuse increases their mobility in the environment, resulting in a need for reliable methods for their determination in a variety of matrices. However, the properties of aminoglycosides, in particular their high polarity, make the development of such methods a non-trivial task, inciting researchers to tackle this complex issue from different...
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Quantum and carbon dots conjugated molecularly imprinted polymers as advanced nanomaterials for selective recognition of analytes in environmental, food and biomedical applications
PublicationSamples with complex matrix analyzed during explanation of pathogenesis of various diseases and food or environmental monitoring request advanced analytical and instrumental devices. Among the materials used for described purposes, quantum (QDs) or carbon dots (CDs) layered by molecularly imprinted polymer (MIP) shells have gained widespread attention. Unique optical and physicochemical properties of QDs/CDs together with high...
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Analysis of MArkers of Exposure to Constituents of Environmental Tobacco Smoke (ETS)
PublicationTobacco smoke is a complex mixture of more than 4000 chemical compounds, many of which are harmful to human health. These compounds belong to various chemical classes, including amides, imides, lactams, carboxylic acids, aldehydes, ketones, alcohols, phenols, amines, hydrocarbons, ethers, and inorganic compounds. There are three types of tobacco smoke streams: the mainstream, the sidestream, and environmental tobacco smoke (ETS)....
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Properties and determination of pesticides in fruits and vegetables
PublicationThe intensive development of agriculture means that more and more toxic organic and inorganic compounds are entering theenvironment. Because of their widespread use, stability, selective toxicity and bioaccumulation, pesticides are among the mosttoxic substances contaminating the environment. They are particularly dangerous in fruit and vegetables, by which people areexposed to them. It is therefore crucial to monitor pesticide...
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Chemometrics and Statistics | Multicriteria Decision Making
PublicationThis contribution describes the application of Multicriteria Decision Making tools in analytical chemistry. The general scheme of MCDM is presented to show its general steps. The most frequently applied in analytical sciences MCDM techniques – AHP, ELECTRE, PROMETHEE and TOPSIS – are briefly described and their advantages and disadvantages are discussed. The applications in analytical chemistry are selection of an appropriate...
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Miniaturized solid phase microextratcion
PublicationWithout any doubt analytical laboratories have an essential role in environmental protection due to the fact that they takes an active part in the monitoring pollutants present in air, water or soil. From the other side, the analytical activity is involved in the generation of toxic waste what is associated with the use of not eco-friendly reagents and solvents. For these reasons, green analytical chemistry (GAC) was introduced...
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The experience of movement in the built form and space: A framework for movement evaluation in architecture
Publication“Movement in architecture” is an organized system of various types of movements stimulated by specific architectural elements. This research was conducted through a qualitative-analytical method and empirical and bibliographical research methods with the aim to categorize different types of movements based on the explorer and observer relationships with the built space and form. So far, most of the related studies have focused...
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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
PublicationA new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an...
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Fast, sensitive and reliable multi-residue method for routine determination of 34 pesticides from various chemical groups in water samples by using dispersive liquid – liquid microextraction coupled with gas chromatography – mass spectrometry
PublicationA simple and efficient dispersive liquid-liquid microextraction technique (DLLME) was developed by using a mixture of two solvents: 40 μL of tetrachlorethylene (extraction solvent) and 1.0 mL of methanol (disperser solvent), which was rapidly injected with a syringe into 10mL ofwater sample. Some important parameters affecting the extraction efficiency, such as type and volume of solvents, water sample volume, extraction time,...
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An evaluation of sucrose as a possible contaminant in e-liquids for electronic cigarettes by hydrophilic interaction liquid chromatography–tandem mass spectrometry
PublicationThe influence of sucrose combustion products on smoking and nicotine addiction is still controversial because the presence of the sucrose may be treated as a source of aldehydes and organic acids. In e-liquids used as refills for electronic cigarettes, which are made primarily of poly(propylene glycol), glycerine and ethanol, sucrose may be present at trace levels, and its impact on mainstream smoke formation, and hence on human...
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Stabilities of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and their derivatives under controlled conditions analyzed using liquid chromatography coupled with tandem mass spectrometry
PublicationBisphenol A diglycidyl ether (BADGE), bisphenol F diglycydyl ether (BFDGE), and their related compounds are widely used as precursors in production of epoxy resins. The high reactivity of these compounds makes the development of analytical methodologies that ensure appropriate metrological accuracy crucial. Consequently, we aimed to determine whether and to what extent the composition of the solution and storage conditions affect...
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Common methods for the chiral determination of amphetamine and related compounds II: Capillary electrophoresis and nuclear magnetic resonance
PublicationAmphetamine group and related ring-substituted substances are generally synthetic compounds, belonging to one of the most heavily abused drug groups in recent years. Some compounds in this class also originate from plants. Analysis of the enantiomers of AM-type compounds and metabolites is extremely important for a number of scientific disciplines. From studies of biological activity or mechanisms through determination of precursor...
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New Polymeric Materials for Solid Phase Extraction
PublicationSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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Identification of novel psychoactive substances 25B-NBOMe and 4-CMC in biological material using HPLC-Q-TOF-MS and their quantification in blood using UPLC–MS/MS in case of severe intoxications
PublicationThis paper describes cases of poisoning caused by new psychoactive substances such as: 25BNBOMe (2-(4-bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine) and 4-CMC (1-(4-chlorophenyl)-2-(methylamino)-1-propanone). The analytical procedure includes rapid and selective method for the extraction and determination of 4-CMC and 25B-NBOMe in blood samples using UPLC–MS/MS technique. To the best of our knowledge,this is...
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Evaluation of the standardisation of gutta-percha points
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Searching for in vitro biomarkers of susceptibility to prostate and cervical cancers by analysis of chromosomal instability, γ-H2AX foci, polymorphisms in DNA repair genes and apoptosis
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Caring for patients with Huntington disease – A survey of caregivers’ experiences and views
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The experience of movement in the built form and space: A framework for movement evaluation in architecture
Publication“Movement in architecture” is an organized system of various types of movements stimulated by specific architectural elements. This research was conducted through a qualitative-analytical method and empirical and bibliographical research methods with the aim to categorize different types of movements based on the explorer and observer relationships with the built space and form. So far, most of the related studies have focused...
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Ranking of Generation Source Locations by a Hybrid Multi-Criteria Method
PublicationThe paper presents a ranking of the locations of eight renewable energy sources (RES) made using a hybrid multi-criteria analysis method. The method is a combination of the analytical hierarchical process (AHP) method and numerical taxonomy. The considered generating sources, i.e. solar plants, biogas plants, and wind farms are sources that will significantly contribute to implementing the provisions of the energy and climate package...
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Principles and Developments of Solid-Phase Microextraction
PublicationSample preparation has been commonly considered a critical step of the analytical process. In this sense, remarkable efforts have been made to develop efficient sample preparation techniques which could overcome the limitations of conventional approaches. Since its inception in the early 1990’s, solid-phase microextraction (SPME) has become a widespread miniaturized sample preparation technique for extraction and preconcentration...
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Truss imperfections in the design of bar and diaphragm bracing systems
PublicationIn the article three variants of roof bracing were considered: bar bracing, diaphragm bracing and the combination of bar and diaphragm bracing. Different analytical and numerical ways of taking into account the imperfections of the truss girder were compared. The entire 3D model of the roof (shell and beam elements with the eccentricities taken into account) was analysed numerically. Selected stressed-skin aspects were considered....
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Poprawa jakości klasyfikacji głębokich sieci neuronowych poprzez optymalizację ich struktury i dwuetapowy proces uczenia
PublicationW pracy doktorskiej podjęto problem realizacji algorytmów głębokiego uczenia w warunkach deficytu danych uczących. Głównym celem było opracowanie podejścia optymalizującego strukturę sieci neuronowej oraz zastosowanie uczeniu dwuetapowym, w celu uzyskania mniejszych struktur, zachowując przy tym dokładności. Proponowane rozwiązania poddano testom na zadaniu klasyfikacji znamion skórnych na znamiona złośliwe i łagodne. W pierwszym...
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Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy
PublicationAlcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures...