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Simultaneous determination of ibuprofen and its metabolites in complex equine urine matrices by GC-EI-MS in excretion study in view of doping control
PublikacjaA novel assay for the simultaneous determination of ibuprofen (IBU) and its four probable metabolites, 1-hydroxyibuprofen (1-OH IBU), 2-hydroxyibuprofen (2-OH IBU), 3-hydroxyibuprofen (3-OH IBU) and carboxyibuprofen (CBX IBU) in equine urine samples with the application of Gas Chromatography-Electron Ionization-Mass Spectrometry (GC-EI-MS) has been developed and elaborated. The new approach for sample preparation including minimizing...
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Composition and antimicrobial activity of fatty acids detected in the hygroscopic secretion collected from the secretory setae of larvae of the biting midge Forcipomyia nigra (Diptera: Ceratopogonidae)
PublikacjaThe hygroscopic secretion produced by the secretory setae of terrestrial larvae of the biting midge Forcipomyia nigra (Winnertz) was analysed using gas chromatography coupled with mass spectrometry (GC-MS). The viscous secretion is stored at the top of each seta and absorbs water from moist air. GC-MS analyses (four independent tests) showed that the secretion contained 12 free fatty acids, the most abundant of which were oleic...
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Profiling and Qualitative Assessment of Enzymatically and Thermally Oxidized Egg Yolk Phospholipids using a Two‐Step High‐Performance Liquid Chromatography Protocol
PublikacjaA two‐step high‐performance liquid chromatography (HPLC) method for the profiling and qualitative assessment of oxidized phospholipids (oxPL) present in foods was developed. The applicability of the investigated two‐step HPLC protocol was verified for separation of enzymatically and thermally oxidized hen egg yolk phospholipids (PL) as a relevant food model. In the first step, seven individual PL classes were separated using hydrophilic...
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Determination of nine high-intensity sweeteners in various foods by high-performance liquid chromatography with mass spectrometric detection
PublikacjaAn analytical procedure involving solid-phase extraction (SPE) and high-performance liquid chromatography-mass spectrometry has been developed for the determination of nine high-intensity sweeteners authorised in the EU; acesulfame-K (ACS-K), aspartame (ASP), alitame (ALI), cyclamate (CYC), dulcin (DUL), neohesperidin dihydrochalcone (NHDC), neotame (NEO), saccharin (SAC) and sucralose (SCL) in a variety of food samples (i.e. beverages,...
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Analysis
PublikacjaNew food products and diverse formulations containing the regulated steviol glycoside(s) as well as Stevia extracts or Stevia leaves have been brought on the global market. The upcoming multitude of such food products, but also their falsification and adulteration, does have impact on food analysis. Robust high-throughput methods that cope with different food matrices are required for food control to ensure food safety. The analysis...
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Chromatographic and Spectroscopic Identification and Recognition of Natural Dyes, Uncommon Dyestuff Components, and Mordants: Case Study of a 16th Century Carpet with Chintamani Motifs
PublikacjaA multi-tool analytical practice was used for the characterisation of a 16th century carpet manufactured in Cairo. A mild extraction method with hydrofluoric acid has been evaluated in order to isolate intact flavonoids and their glycosides, anthraquinones, tannins, and indigoids from fibre samples. High-performance liquid chromatography coupled to spectroscopic and mass spectrometric detectors was used for the identification of...
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Environmental Fate of Two Psychiatric Drugs, Diazepam and Sertraline: Phototransformation and Investigation of their Photoproducts in Natural Waters
PublikacjaExperimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry...
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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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Comparative evaluation of different methods for determining phytochemicals and antioxidant activity in products containing betalains - Verification of beetroot samples
PublikacjaThis study presents methods that can be used to assess the health quality of products containing betalains. The paper compares and verifies data on the phytochemical composition of three different pigmented beetroot cultivars using spectrophotometric, HPLC-DAD, HPTLC and LC-Q-Orbitrap-HRMS techniques. Additionally, we compared the total antioxidant activity in both the cell-free and cellular systems. Betalain contribution to antioxidant...
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The use of HPLC-Q-TOF-MS for comprehensive screening of drugs and psychoactive substances in hair samples and several “legal highs” products
PublikacjaNon-targeted screening of drugs present in herbal products, known as “legal high” drugs and in hair as a biological matrix commonly used in toxicological investigations was accomplished with the use of high pressure liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS). In total, 25 and 14 therapeutical drugs and psychoactive substances/metabolites were detected in investigated hair samples...
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Determination of impurities in pharmaceutical products using LC-MS
PublikacjaPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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Pesticide residues levels in honey from apiaries located of Northern Poland
PublikacjaConcentration levels of 30 pesticide residues were measured in honey samples collected from apiaries in northern part of Poland (Pomerania) using method based on the QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry with electron spray ionization (LC-ESI-MS/MS). In 29% of the samples were found positive for at least some of the target compounds. Concentration of bifenthrin, fenpyroximate, methidathion,...
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Occurrence and Levels of Biogenic Amines in Beers Produced by Different Methods
PublikacjaThe concentration of biogenic amines (BAs) in beer depends, among other factors, on the activity of microorganisms, in particular lactic acid bacteria. In this work an analytical method based on derivatization with tosyl chloride and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine 17 BAs in samples of commercially available beers, and to monitor the changes in concentration of...
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Określenie zawartości lotnych kwasów tłuszczowych (LKT) w odciekach pochodzących z mikrobiologicznej degradacji monosacharydów
PublikacjaOkreślenie zawartości lotnych kwasów tłuszczowych (LKT) w odciekach pochodzących z mikrobiologicznej degradacji monosacharydów. Milena Jabłońska, Maria Rybarczyk, Marta Wisielewska, Marek Lieder Politechnika Gdańska, Wydział Chemiczny, Katedra Technologii Chemicznej Zawartość lotnych kwasów tłuszczowych (LKT) w metabolitach pochodzących z mikrobiologicznego ogniwa paliwowego (MFC – Microbial Fuel Cell) świadczy o rozkładzie...
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Determination of Glycerol, Propylene Glycol, and Nicotine as the Main Components in Refill Liquids for Electronic Cigarettes
PublikacjaRefill liquids for electronic cigarettes are an important area of research due to the health safety and quality control of such products. A method was developed for the determination of glycerol, propylene glycol, and nicotine in refill liquids using liquid chromatography, coupled with tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring (MRM) mode with electrospray ionisation (ESI). Sample preparation was based...
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FTIR spectra and IGC chromatograms for chemically reduced graphene oxide aerogels (rGOA)
Dane BadawczeThe effect of selected synthesis parameters on reduced graphene oxide aerogels properties was investigated using Fourier-transform infrared spectroscopy and dynamic adsorption method (Inverse Gas Chromatography, IGC). Samples were synthesized by sol-gel method by reduction induced self-assembly of graphene oxide. As a reductant l-ascorbic acid was used....
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Polymer biodegradable coatings as active substance release systems for urological applications
PublikacjaCatheter-associated urinary tract infections are the result of catheterization of the bladder. The risk of infection is directly proportional to the length of the bladder catheterization. Bacteria cells have the ability to adhere and create the biofilm on the surface of catheter materials. Bacteria’s biofilm is an extremely beneficial environment of existence for microorganisms. Microorganisms that are an integral part of the biofilm...
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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublikacjaThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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Development of different methods for drugs and psychoactive substances extraction from hair samples and their identification based on HPLC-ESI-QTOF analysis
PublikacjaOver the past decade, the use of non-controlled designer drugs and drug of abuse has rapidly increased. Hair, as a human matrix, enables detection of drugs incorporated into its structure. Studies of presence and identification of drug metabolites in human hair samples has been performed using liquid chromatography electrospray ionization quadrupole time of flight mass spectrometry (HPLC-ESI-QTOF-MS) with steady alternation of...
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Bisphenols and their derivatives in baby diaper samples.
PublikacjaMany common products contain and leach hazardous chemicals, including endocrine-disrupting chemicals such as bisphenols that are harmful to human health. For toddlers, this dangerousness is higher because of their not fully developed detoxification system. Due to this, bisphenols content in products such as baby diapers, should be monitored. Baby diapers not only remain in close contact with the skin, but are also used from the...
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Analytical Strategies and Applications in Lipidomics
PublikacjaLipidomics is a field of study aiming at a comprehensive analysis of a set of lipids in biological systems. This includes both quantitative and qualitative characterization of lipid profiles, comparative studies of lipidomes, and analysis of lipid-protein interactions. Lipids are structurally diversified that make their analysis a challenging task. The constant advances in analytical technologies, especially in the field of high-performance...
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INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
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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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LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
PublikacjaPharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid...
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Development of potential candidate reference materials for drugs in bottom sediment, cod and herring tissues
PublikacjaRegular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32...
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Novel materials and approaches for solid-phase (micro) extraction in LC-MS-based metabolomics
PublikacjaMetabolomics offers a unique approach to study biological systems. Liquid chromatography coupled to mass spectrometry serves as a powerful analytical tool to analyze complex mixtures of metabolites. However, successful metabolomic analysis relies on sample preparation. While untargeted analysis traditionally favors nonselective procedures like liquid-liquid extraction (LLE), these methods can compromise analytical performance due...
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Extraction and Analysis of Bisphenols and Their Derivatives in Infant and Toddler Ready-to-feed Meals by Ultrasound-assisted Membrane Extraction Followed by LC MS/MS
PublikacjaThis research developed an ultrasound-assisted membrane extraction coupled with liquid chromatography-tandem mass spectrometry method for the determination of nineteen bisphenols and their derivatives in infant and toddler ready-to-feed meals. The calibration curves for all analytes were linear in the tested range, and the limit of detection and limit of quantitation were in the range 0.27 to 0.79 ng/g and 0.80 to 2.4 ng/g, respectively....
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Determination of aminoglycoside antibiotics: current status and future trends
PublikacjaThe 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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Role of Silicon in Counteracting Cadmium Stress in Pea Plants (Pisum sativum L.): Insights Into Cadmium Binding Mechanisms and Pectin Methylesterase Activity
PublikacjaPurpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity...
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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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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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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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A new dilution-enrichment sample preparation strategy for expanded metabolome monitoring of human breast milk that overcomes the simultaneous presence of low- and high-abundance lipid species
PublikacjaThe complex nature of human breast milk (HBM) makes samples difficult to analyze, requiring several extraction techniques and analytical platforms to obtain high metabolome coverage. In this work, we combined liquid-liquid extraction (LLE) and solid-phase extraction (SPE) techniques to prepare HBM samples to overcome the challenge of low- and high-abundance lipid species, enabling the semiquantitative analysis of total HBM lipids...
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Serum bisphenol A concentrations correlate with serum testosterone levels in women with polycystic ovary syndrome
PublikacjaThe aim of this study was to determine serum bisphenol A (BPA) concentrations using high performance liquid chromatography with tandem mass spectrometry (HPLC–MS/MS) in women with polycystic ovary syndrome (PCOS) (n=106, age range 18–40 yrs) and to evaluate its potential impact on their hormonal and metabolic profile. The control group consisted of age- and BMI-matched 80 eumenorrheic women with no clinical or biochemical hyperandrogenism....
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Lipidomics of Staphylococcus aureus – a new insight into the antibiotic resistant phenotype
PublikacjaStaphylococcus aureus is an aggressive pathogen responsible for a variety of diseases, in cluding life-threatening sepsis. Many strains of these bacteria are resistant to multiple classes of antibiotics, which is a substantial clinical problem in the treatment of S. aureus infections. We developed a comprehensive untargeted lipidomic workflow, including sample preparation, liquid chromatography-quadrupole-time-of-flight mass spectrometry...
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Effects of liquid phase modification on the performance of biotrickling filters
Dane BadawczeDataset presents the effects of liquid phase modification on the biotrickling filtration (BTF) performance of air polluted with toluene, ethylbenzene, xylene and styrene.
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Exposure scenario and risk assessment of infants and newborns to bisphenols and their derivatives from diapers
PublikacjaNewborns and infants are more sensitive to harmful compounds such as bisphenols and their derivatives because of their not fully developed detoxification mechanism. Exposure to these substances can lead to developmental problems and health consequences in adulthood. Since disposable baby diapers are used from the first days of life and remain in contact with the baby skin, it seems important to monitor the levels of endocrine disrupting chemicals...
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Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
PublikacjaThe TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the...
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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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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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Preconcentration and Analytical Methods for Determination of Methyl Tert-Butyl Ether and Other Fuel Oxygenates and Their Degradation Products in Environment: A Review
PublikacjaFuel oxygenates (FOs) are mainly ethers or alcohols which are added to gasoline either to boost the octane number or to make the fuel burning process more "cleaner" with increasing the oxygen content, or to obtain a combination of both effects. FOs are water soluble with high mobility in the environment which presence even at very low concentrations lower the quality of water making it unsafe or unpleasant due to their objectionable...
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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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Mass Spectrometry
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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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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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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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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
PublikacjaA 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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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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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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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,...