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Wyniki wyszukiwania dla: liquid chromatography
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Determination of volatile organic compounds in water samples using membrane-solid phase microextraction (M-SPME) (headspace version)
PublikacjaThe results of a study on the use of membrane-solid phase microextraction (M-SPME) for sampling volatile organic compounds (VOCs) from the headspace above the liquid medium are presented. The sampled VOCs were subsequently quantified by gas chromatography (GC). Two systems were compared in this study, i.e. a novel two-phase sorption system (M-SPME), and a commercial fibre. Headspace sampling using SPME was optimized with respect...
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Concentration of Potentially Bioactive Compounds in Italian Extra Virgin Olive Oils from Various Sources by Using LC-MS and Multivariate Data Analysis
PublikacjaHigh quality extra virgin olive oils represent an optimal source of nutraceuticals. The European Union (EU) is the world’s leading olive oil producer, with the Mediterranean region as the main contributor. This makes the EU the greatest exporter and consumer of olive oil in the world. However, small olive oil producers also contribute to olive oil production. Beneficial effects on human health of extra virgin olive oil are well...
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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
PublikacjaAlcohol 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...
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Separation and determination of the group-type composition of modern base and lubricating oils with a wide range of polarity, especially emitted to the environment
PublikacjaLubricating oils are composed of base oils (>85% v/v) and enriching additives (<15% v/v). Three types of base oils may be distinguished: 1) traditional bases (obtained by low-volatile fractions from crude oil distillation refining), 2) synthetic bases (mainly poly-alpha-olefins, sometimes esters, especially succinic acid esters), 3) bases of natural origin (especially obtained from refined plant oils). The bases of natural origin...
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Chromatographic behaviour of ionic liquid cations in view of quantitative structure-retention relationship
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Analityka surfaktantów w próbkach środowiskowych
PublikacjaSurfaktanty stanowią grupę związków charakteryzujących się specyficznymi właściwościami fizykochemicznymi (m.in. amfifilowa budowa, zdolność rozpuszczania się w cieczach o różnej polarności, zdolność do tworzenia micelli) i z tego względu są one wykorzystywane w wielu sferach działalności człowieka. Związki powierzchniowo-czynne ulegają różnorodnym przemianom fizykochemicznym, co umożliwia ich migrację między różnymi elementami...
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Extractive detoxification of hydrolysates with simultaneous formation of deep eutectic solvents
PublikacjaThe hydrolysis of lignocellulosic biomass results in the production of so-called fermentation inhibitors, which reduce the efficiency of biohydrogen production. To increase the efficiency of hydrogen production, inhibitors should be removed from aqueous hydrolysate solutions before the fermentation process. This paper presents a new approach to the detoxification of hydrolysates with the simultaneous formation of in-situ deep eutectic...
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Presence of antibiotics in the aquatic environment in Europe and their analytical monitoring: Recent trends and perspectives
PublikacjaThe presence of antibiotics and their metabolites in the aquatic environment exerts a negative impact on all organisms. Moreover, the easy migration of these substances to drinking water may also have serious consequences for public health, such as drug resistance. Although antibiotics and their metabolites are detected in surface waters and wastewater, there are still no systemic solutions preventing environmental pollution with...
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Introduction to MIP synthesis, characteristics and analytical application
PublikacjaOne of the trends in analytical chemistry is associated with designing and developing new types of sample preparation techniques, which might significantly increase the efficiency and selectivity of the analytes isolation or/and preconcentration process. One of the most widely employed solutions are selective sorption materials, defined as molecularly imprinted polymers (MIPs), as well as the sorbents with the molecular fingerprint....
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A comprehensive lipidomic analysis of oilseeds using LC-Q-TOF-MS and dispersive micro-solid phase (D-μ-SPE) extraction techniques
PublikacjaGrowing public health awareness increased the demand for natural products with positive health benefits. Vegetable oils containing omega-3 fatty acids (FA) such as alpha-linolenic acid (ALA) has been proposed as a possible source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In this work, a comprehensive lipidome analysis and comparison of seven oilseeds, including flaxseed, chia, hemp, black cumin, white sesame,...
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Comparative Study on Assisted Solvent Extraction Techniques for the Extraction of Biologically Active Compounds from Sideritis raeseri and Sideritis scardica
PublikacjaThe plants in the Sideritis genus are postulated to exhibit several important medicinal properties due to their unique chemical composition. To isolate the targeted phytochemical compounds, the selection of a suitable extraction method is of primary importance. In this work, a comparative study on the phytochemical profiles of various Sideritis raeseri and Sideritis scardica extracts has been carried out. An untargeted metabolomics...
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Primary degradation of antidiabetic drugs
PublikacjaType 2 diabetes is a chronic disease affecting a large portion of the world population and is treated by orally administered drugs. Since these drugs are often taken in high doses and are excreted unchanged or partially metabolised many of them are nowadays detected in surface waters or wastewater treatment plants effluents. Unmetabolised antidiabetics or some of their transformation products retain their pharmacological activity,...
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Untargeted Lipidomics Reveals Differences in the Lipid Pattern among Clinical Isolates of Staphylococcus aureus Resistant and Sensitive to Antibiotics
PublikacjaStaphylococcus aureus resistance to antibiotics is a significant clinical problem worldwide. In this study, an untargeted lipidomics approach was used to compare the lipid fingerprints of S. aureus clinical isolates that are resistant and sensitive to antibiotics. High-performance liquid chromatography coupled with time-of-flight mass spectrometry was employed to rapidly and comprehensively analyze bacterial lipids. Chemometric...
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Metals and metal-binding ligands in wine: Analytical challenges in identification.
PublikacjaBackground Due to important role of metals in the vinification process as well as their impact on the human health, their content in this alcoholic beverage has been extensively studied by many researchers. It is already known that speciation of metals determines their toxicity and bioavailability as well as influences their activity. Understanding the chemistry and knowing the structures of metal complexes could have relevant...
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Influence of Storage Time and Temperature on the Toxicity, Endocrine Potential, and Migration of Epoxy Resin Precursors in Extracts of Food Packaging Materials
PublikacjaThe aim of the present study was to establish a standard methodology for the extraction of epoxy resin precursors from several types of food packages (cans, multi-layered composite material, and cups) with selected simulation media (distilled water, 5% ethanol, 3% dimethyl sulfoxide, 5% acetic acid, artificial saliva) at different extraction times and temperatures (factors). Biological analyses were conducted to determine the acute...
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Determination of MDPBP in postmortem blood samples by gas chromatography coupled with mass spectrometry
PublikacjaMDPBP (1-(3,4-methylenedioxyphenyl)-2-(1-pyrrolidinyl)-1-butanone) is a new psychoactive substance sold on the black market. It has been a controlled drug of abuse in Poland and China since 2015 as some toxic and fatal cases connected with use of synthetic cathinone derivatives were observed. The fatal case outlined here concerns a 19 year-old man, who was found dead with an envelope containing white powder lying nearby the cadaver....
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Determination of benzodiazepines and Z-hypnotic drugs in whole blood samples by GC–MS/MS: Method development, validation and application
PublikacjaBenzodiazepines (BZDs) and Z-drugs are widely used as anxiolytics, sedative hypnotics, anticonvulsants and muscle relaxants. “Designer benzodiazepines” (DBZDs) are a new psychoactive substance class consisting of benzodiazepine derivatives that are not allowed for medical use and are known for being used recreationally. From a toxicologist standpoint, the huge number of such substances implicate a necessity for developing fast...
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Assessment of baby disposable diapers application for urine collection and determination of phthalate metabolites
PublikacjaThe baby disposable diapers were investigated as a sampling material for urine collection and validated for the evaluation of the exposure of children to xenobiotics. Phthalate metabolites detected in urine samples were chosen as proof-of-concept analytes. For the determination of phthalate metabolites in children’s urine samples, high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was used. Two...
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The Impact of Different Drying Methods on the Metabolomic and Lipidomic Profiles of Arthrospira platensis
PublikacjaDrying is an inseparable part of industrial microalgae production. In this work, the impacts of eight different drying methods on the metabolome and lipidome of Arthrospira platensis were investigated. The studied drying methods were freeze drying (FD), sun drying (SD), air drying at 40 and 75 °C (AD′ and AD″), infrared drying at 40 and 75 °C (IRD′ and IRD″), and vacuum drying at 40 and 75 °C (VD′ and VD″). Results gathered by...
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Mass spectrometry based identification of geometric isomers during metabolic stability study of a new cytotoxic sulfonamide derivatives supported by quantitative structure-retention relationships
PublikacjaA set of 15 new sulphonamide derivatives, presenting antitumor activity have been subjected to a metabolic stability study. The results showed that besides products of biotransformation, some additional peaks occurred in chromatograms. Tandem mass spectrometry revealed the same mass and fragmentation pathway, suggesting that geometric isomerization occurred. Thus, to support this hypothesis, quantitative structure-retention relationships...
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Asfalteny jako fazy stacjonarne w chromatografii cieczowej w normalnych układach faz
PublikacjaRozprawa doktorska dotyczy zbadania możliwości wykorzystania asfaltenów wydzielonych z: próżniowej pozostałości ropy naftowej, produktów jej utleniania i naturalnego asfaltu jako fazy stacjonarnej na powierzchni sorpcyjnej żelu krzemionkowego do rozdzielania nisko polarnych organicznych związków chemicznych w warunkach chromatografii cieczowej w normalnych układach faz, w odniesieniu do żelu krzemionkowego jako nośnika. Opracowano...
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Validation and modification of HPLC method for monitoring acetaminophen plasma concentrations in patients with chronic pancreatitis
PublikacjaBackground. Pancreatitis is the inflammation of the pancreas. The infl ammation may occur suddenly and resolve in a few days with the treatment in case of acute pancreatitis (AP). Chronic pancreatitis (CP) is a persistent inflammation of the pancreas that results in irreversible morphological changes and impairment of both exocrine and endocrine functions. Abdominal...
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Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
PublikacjaFor many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional...
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Ionogel sorbent coatings for determining organophosphorus and pyrethroid insecticides in water and fresh juice samples by headspace-solid phase microextraction
PublikacjaThe sol–gel method yielded three different ionogel sorbent coatings that were obtained based on a silica material containing ionic liquids (ILs) immobilized in its pores. Two ILs, triethylsulfonium bis(trifluoromethylsulfonyl) imide [Set3][TFSI] and 1-butyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide [C4C1Pip][TFSI], as well as their equimolar mixture [Set3/C4C1Pip], were used to obtain ionogel fibers. The developed...
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Simultaneous opto-electrochemical monitoring of carbamazepine and its electro-oxidation by-products in wastewater
PublikacjaThe growing human impact on aquatic environments, due to the extensive use of pharmaceuticals and the release of persistent pollutants, makes it necessary to implement new widespread methods for the characterisation and quantification of such contaminants and relative degradation products. Carbamazepine, 5H-dibenzo[b,f]azepine-5-carboxamide, (CBZ) is a widely used anti-epileptic drug, characterised by its limited removal by conventional...
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A hierarchical porous composite magnetic sorbent of reduced graphene oxide embedded in polyvinyl alcohol cryogel for solvent‐assisted‐solid phase extraction of polycyclic aromatic hydrocarbons
PublikacjaA hierarchical porouscomposite magnetic sorbent was fabricated and applied tothe dispersive solvent-assisted solid-phase extraction of five polycyclic aromatichydrocarbons. A sorbent was first prepared by incorporating graphene oxide,calcium carbonate, and magnetite nanoparticles into a polyvinyl alcohol cryo-gel. The graphene oxide was converted to reduced graphene oxide using ascorbicacid and a hierarchical porous structure was...
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Multi-Technique Investigation of Grave Robes from 17th and 18th Century Crypts Using Combined Spectroscopic, Spectrometric Techniques, and New-Generation Sequencing
PublikacjaThe textile fragments of the funeral clothes found in the 17th and 18th century crypts were subjected to spectroscopic, spectrometric, and microbial investigation. The next-generation sequencing enabled DNA identification of microorganisms at the genus and in five cases to the species level. The soft hydrofluoric acid extraction method was optimized to isolate different classes of dyes from samples that had direct contact with...
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Concentrations of alfa- and gamma- tocopherols in human breast milk during the first months of lactation and in infant formulas
PublikacjaThe aim of this study was to determine the concentrations of alpha- and gamma-tocopherols in human breast milk samples from different periods of lactation and to compare them with tocopherol content in commercially available formulas for infants at corresponding ages. The study included 93 breast milk samples obtained on the 2nd (colostrum, n=17), 14th (n=30), 30th (n=27) and 90th day of lactation (n=19), along with 90 samples...
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The dose-dependet influence of zinc and cadmium contamination of soil on their uptake and glucosinolate content in white cabbage (Brassica oleracea var. capitata f. alba)
PublikacjaThe relationship between the ability to accumulate heavy metals (represented by Cd and Zn) and to synthesize bioactive compounds (represented by glucosinolates[GLS]) was investigated in two cabbage cultivars. Plants were grown in the greenhouse of a phytotron under controlled conditions in soils spiked with two different Zn or Cd concentrations. The measurements of Cd and Zn contents in soil and cabbage (leaf) samples were performed...
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A Closed Bipolar Electrochemical Cell for the Interrogation of BDD Single Particles: Electrochemical Advanced Oxidation
PublikacjaA closed bipolar electrochemical cell containing two conductive boron-doped diamond (BDD) particles of size 250 – 350 m, produced by high-pressure high-temperature (HPHT) synthesis, has been used to demonstrate the applicability of single BDD particles for electrochemical oxidative degradation of the dye, methylene blue (MB). The cell is fabricated using stereolithography 3D printing and the BDD particles are located at either...
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Plant-based meat substitute analysis using microextraction with deep eutectic solvent followed by LC-MS/MS to determine acrylamide, 5-hydroxymethylfurfural and furaneol
PublikacjaFor the analysis of plant-based meat substitutes and the determination of Maillard reaction products such as acrylamide, 5-hydroxymethylfurfural and furaneol, a novel and effective procedure based on hydrophobic natural deep eutectic solvent and liquid chromatography coupled with tandem mass spectrometry was developed for the first time. The 49 compositions of the deep eutectic solvents were designed and screened to select the...
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Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare
PublikacjaLigustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been histori-cally recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from differ-ent morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance...
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The Effect of Hyperbaric Storage on the Nutritional Value and Retention of Certain Bioactive Proteins in Human Milk
PublikacjaHuman milk (HM) contains the essential macronutrients and bioactive compounds necessary for the normal growth and development of newborns. The milk collected by human milk banks is stored frozen and pasteurized, reducing its nutritional and biological value. The purpose of this study was to determine the effect of hyperbaric storage at subzero temperatures (HS-ST) on the macronutrients and bioactive proteins in HM. As control samples,...
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The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans
PublikacjaCruciferous vegetables represent a valuable source of bioactive compounds. However, there is currently a deficiency of information regarding the extent to which these compounds remain bioaccessible to the body following thermal treatment and digestion processes within the digestive tract. Accordingly, the aim of this study was to evaluate the impact of heat treatment and in vitro digestion on the level of selected bioactive compounds...
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A multi-analytical approach to the characterization of natural organic dyestuffs and inorganic substrates present in the 19th-century artistic oil paints manufactured by a French art materials supplier Richard Aines
PublikacjaThis paper presents a comprehensive analysis of artistic paints produced in the 19th century by a French art materials supplier Richard Ain`es. Improved mild extraction with hydrofluoric acid enabled the observation of intact organic dyes. Reversed-phase liquid chromatography with diode-array and mass spectrometry detection was utilised for the identification of 35 dyes present in yellow and red paint samples, and in selected plant...
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Comparative Lipidomic Study of Human Milk from Different Lactation Stages and Milk Formulas
PublikacjaIn this report, we present a detailed comparison of the lipid composition of human milk (HM) and formula milk (FM) targeting different lactation stages and infant age range. We studied HM samples collected from 26 Polish mothers from colostrum to 19 months of lactation, along with FM from seven brands available on the Polish market (infant formula, follow-on formula and growing-up formula). Lipid extracts were analysed using liquid...
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Electrochemical and in silico approaches for liver metabolic oxidation of antitumor-active triazoloacridinone C -1305
Publikacja5-Dimethylaminopropylamino-8-hydroxytriazoloacridinone (C-1305) is a promising antitumor compound developed in our laboratory. A better understanding of its metabolic transformations is still needed to explain the multidirectional mechanism of pharmacological action of triazoloacridinone derivatives at all. Thus, the aim of the current work was to predict oxidative pathways of C-1305 that would reflect its phase I metabolism. The...
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Structure and Stability Characterization of Natural Lake Pigments Made from Plant Extracts and Their Potential Application in Polymer Composites for Packaging Materials
PublikacjaNatural dyes were extracted from various plant sources and converted into lake pigments based on aluminum and tin. Three different plants (weld, Persian berries, and Brazilwood) were chosen as representative sources of natural dyes. High-performance liquid chromatography (HPLC) and triple-quadrupole mass spectrometry (QqQ MS) were used to identify dyestuffs in the raw extracts. The natural dyes and lake pigments were further characterized...
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The Education of Analytical Chemists in Polish Universities
PublikacjaAnalytical Chemistry plays a very important role in the modern world. The main reasons are; the need of environmental monitoring, quality of food and water control, human health, quality of industrial production control, nanotechnologies and material science. Together with Inorganic Chemistry, Organic Chemistry and Physical Chemistry, Analytical Chemistry is a fundamental chemical course. The education of Analytical Chemists is...
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Quality control of cheese samples for the presence of natamycin preservative – A natural deep eutectic solvent (NADES) based extraction coupled with HPLC
PublikacjaA new protocol for the determination of natamycin – an antifungal agent used as a food preservative - in cheese samples – is described. This new method is based on a natural deep eutectic solvent (NADES) green extraction procedure. High-performance liquid chromatography (HPLC) was used for detection and quantification. NADESs with different molar ratios were evaluated for efficient and selective extraction. NADES made of thymol...
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Multi-Analytical Techniques for the Study of Burial Clothes of Polish King Sigismund III Vasa (1566–1633) and His Wife Constance Habsburg (1588–1631)
PublikacjaThe subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance...
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Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
PublikacjaA rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean...
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Phototransformation of Amlodipine: Degradation Kinetics and Identification of Its Photoproducts
PublikacjaNowadays, monitoring focuses on the primary compounds and does not include degradation products formed during various biological and chemical processes. Transformation products may have the same effects to human health and the environment or sometimes they can be more toxic than the parent compound. Unfortunately, knowledge about the formation of degradation products is still limited, however, can be very important for the environmental...
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Recent advancements in LC‐MS based analysis of biotoxins: Present and future challenges
PublikacjaThere has been a rising concern regarding the harmful impact of biotoxins, source of origin, and the determination of the specific type of toxin. With numerous reports on their extensive spread, biotoxins pose a critical challenge to figure out their parent groups, metabolites, and concentration. In that aspect, liquid chromatography‐mass spectrometry (LC‐MS) based analysis paves the way for its accurate identification and quantification....
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Phototransformation of three selected pharmaceuticals, naproxen, 17α-Ethinylestradiol and tetracycline in water: Identification of photoproducts and transformation pathways
PublikacjaTransformation products (TPs) may be formed during various processes, however, it was proved that one of the main mechanisms responsible for degradation of pharmaceuticals in natural waters is photolysis. Three compounds were selected, tetracycline (TC), 17-α-ethinylestradiol (EE2) and naproxen (NAP), for degradation experiments which were performed using a xenon lamp emitting light with a spectrum closely approximating that of...
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Measurements of Activity Coefficients at Infinite Dilution for Organic Solutes in the Ionic Liquids N-Ethyl- and N-Octyl-N-methylmorpholinium Bis(trifluoromethanesulfonyl)imide. A Useful Tool for Solvent Selection
PublikacjaIn recent years, many papers describing ionic liquids (IL) as promising solvents in separation techniques have been published. The conscious choice of appropriate ionic liquid as absorption media in effective extraction of selected types of analytes requires deeper understanding of the analyte−IL interactions. Therefore, intensive research is conducted to determine the values of activity coefficient at infinite dilution, which...
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Żółte barwniki organiczne w XIX-wiecznych farbach Jana Matejki - identyfikacja substancji barwiących, nośników, oraz wypełniaczy
PublikacjaNaturalne barwniki organiczne można znaleźć w wielu obiektach dziedzictwa kulturowego. Identyfikacja substancji barwiących obecnych w farbach historycznych dostarcza istotnych informacji dla wielu specjalistów zaangażowanych w naukę o sztuce. Identyfikacja składu farb pozwala na zastosowanie odpowiednich procedur dotyczących renowacji i konserwacji historycznych dzieł sztuki. Informacje te pozwalają na ich renowację zgodnie z decyzjami...
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Novel insights into conjugation of antitumor-active unsymmetrical bisacridine C-2028 with glutathione: characteristics of non-enzymatic and glutathione S-transferase-mediated reactions
PublikacjaUnsymmetrical bisacridines (UAs) are a novel potent class of antitumor-active therapeutics. A significant route of phase II drug metabolism is conjugation with glutathione (GSH), which can be non-enzymatic and/or catalyzed by GSH-dependent enzymes. The aim of this work was to investigate the GSH-mediated metabolic pathway of a representative UA, C 2028. GSH supplemented incubations of C-2028 with rat, but not with human, liver...
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Superhydrophobic sponges based on green deep eutectic solvents for spill oil removal from water
PublikacjaThe paper described a new method for crude oil-water separation by means of superhydrophobic melamine sponges impregnated by deep eutectic solvents (MS-DES). Due to the numerous potential of two-component DES formation, simple and quick screening of 156 non-ionic deep eutectic solvents using COSMO-RS (Conductor-like Screening Model for Real Solvents) computational model was used. DES which were characterized by high solubility...
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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...