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Search results for: HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC)
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Validation and modification of HPLC method for monitoring acetaminophen plasma concentrations in patients with chronic pancreatitis
PublicationBackground. 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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Concentration of Potentially Bioactive Compounds in Italian Extra Virgin Olive Oils from Various Sources by Using LC-MS and Multivariate Data Analysis
PublicationHigh 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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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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The lipophilicity indices of flavonoids estimated by reversed-phase liquid chromatography using different computation methods
PublicationDo oceny właściwości chromatograficznych wybranych flawonoidów zastosowano wyskokosprawną chromatografię cieczową z odwróconym układem faz i kolumnami chromatograficznymi typu C-8 i C-18.Lipofilowość wyrażono za pomocą różnych deskryptów lipofilowości.
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Lipophilicity data for some preservatives estimated by reversed-phase liquid chromatography and different copmutation methods
PublicationW pracy przedstawiono wyniki badań właściwości chromatograficznych wybranych 12 związków z grupy kopnserwantów. Lipofilowy charakter tych związków był oceniany na podtsawie różnych parametrów retencyjnych (log Kw, log K i inne. Zastosowano narzędzie chemometryczne do zbadania korelacji występujących pomiędzy tymi parametrami retencji chromatogfraficznej.
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Measurement of activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide using gas–liquid chromatography
PublicationBased on gas–liquid chromatography (GLC) retention data, activity coefficients at infinite dilution of 39 different solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide ([HDABCO][NTf2]) have been determined. Measurements covered a broad range of types of organic solutes including alkanes, alcohols, ketones, benzene derivatives and McReynold’s compounds. Activity coefficients were...
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The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublicationIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
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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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Determination of Pesticide Residues in Honeybees using Modified QUEChERS Sample Work-Up and Liquid Chromatography-Tandem Mass Spectrometry
PublicationIncreasing emissions of chemical compounds to the environment, especially of pesticides, is one of factors that may explain present honeybee colony losses. In this work, an analytical method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized for the simultaneous screening of 19 pesticides which have not been yet determined in honeybee samples from northern Poland (Pomerania). The sample preparation,...
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Extractive detoxification of hydrolysates with simultaneous formation of deep eutectic solvents
PublicationThe 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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Serum bisphenol A concentrations correlate with serum testosterone levels in women with polycystic ovary syndrome
PublicationThe 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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Sensitive determination of isoprostanes in exhaled breath condensate samples with use of liquid chromatography–tandem mass spectrometry
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Direct Screening ofWater Samples for Benzene Hydrocarbon Compounds by Headspace Liquid-Phase Microextraction--Gas Chromatography
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Direct screening of ground water samples for fuel oxygenates by headspace liquid phase microextraction–gas chromatography
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Rapid Characterization of the Human Breast Milk Lipidome Using a Solid-Phase Microextraction and Liquid Chromatography-Mass Spectrometry-Based Approach.
PublicationHuman breast milk (HBM) is a biofluid consisting of various biomolecules such as proteins, lipids, carbohydrates, minerals and bioactive substances. Due to its unique and complex composition, HBM provides not only nutritional components required for the growth of the infant, but also additional protection against infections. Global insight into the composition of HBM is crucial to understanding the health benefits infants receive...
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Assessment of baby disposable diapers application for urine collection and determination of phthalate metabolites
PublicationThe 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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Accurate, Direct, and High-Throughput Analyses of a Broad Spectrum of Endogenously Generated DNA Base Modifications with Isotope-Dilution Two-Dimensional Ultraperformance Liquid Chromatography with Tandem Mass Spectrometry: Possible Clinical Implication
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Discrepancies in determination of biogenic amines in beer samples by reversed phase and hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry
PublicationBiogenic amines (BAs) are nitrogenous organic bases occurring mainly in fermented food and beverages as a result of free amino acids bacterial decarboxylation. The reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) based methods were compared in terms of usefulness for determination of BAs in beer samples. Analysis of BAs with the use of RPLC method were carried out after their...
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Some aspects of the analysis of environmental pollutants in sediments using pressurized liquid extraction and gas chromatography-mass spectrometry
PublicationOpisano wyniki badań nowej procedury oznaczania analitów z grupy wielopierścieniowych węglowodorów aromatycznych oraz polichlorowanych bifenyli w próbkach osadów dennych. Szczególnie dużo uwagi poświęcono zbadaniu możliwości wykorzystania techniki przyspieszonej ekstrakcji analitów za pomocą rozpuszczalnika na etapie izolacji wzbogacania. Ustalono również warunki oznaczeń końcowych z wykorzystaniem techniki GC-MS.
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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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Identification and characterization of the Indian Yellow dyestuff and its degradation products in historical oil paint tube by liquid chromatography mass spectrometry
PublicationAn analytical protocol for identification of dyes using reversed phase liquid chromatography-mass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/MS) is presented. The developed method has been successfully applied in identification of euxanthic acid and euxanthone, the main components of the Indian Yellow dye in a historical oil paint tube produced by Richard Ain`es, a recognizable French company supplying...
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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
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Partition coefficients of selected environmentally important volatile organic compounds determined by gas - liquid chromatography with polydimethylsiloxane stationary phase
PublicationPrzedstawiono wartości współczynników podziału (stałych podziału) 14 lotnych związków organicznych istotnych dla stanu środowiska (często oznaczanych w powietrzu w pomieszczeniach zamkniętych) między fazą gazową (N2) a ciekłą (PDMS). Wyznaczano je dwiema technikami (izotermiczną i z liniowo programowanym wzrostem temperatury). Dowiedziono, że istnieje możliwość wyznaczania współczynników podziału techniką LTPRI w oparciu o skalę...
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Determination of nonsteroidal antiinflammatory drugs in water samples using liquid chromatography coupled with diode-array detector and mass spectrometry
PublicationOpracowano i zwalidowano metodykę do oznaczania śladowych ilości sześciu różnych związków z grupy niesteroidowych leków przeciwzapalnych w próbkach wodnych. Anality zostały wybrane spośród najczęsciej sprzedawanych leków w Polsce. Sprawdzono kilka różnych kolumienek ekstrakcyjnych i wybrano RP-18 jako najlepsze wypełnienie do wzbogacania oznaczanych związków. Opracowaną metodykę z powodzeniem zastosowano do analizy próbek rzeczywistych.
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Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
PublicationExtracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis...
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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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The efficiency comparison of ramentaceone isolation from Drosera aliciae plants using normal and reversed phase preparative liquid chromatography technique
PublicationW pracy zaprezentowano optymalne warunki otrzymywania ramentaceonu z chloroformowego ekstraktu z rośliny D. muscipula. Opracowano i przedstawiono dwie procedury otrzymywania ramantaceonu z wykorzystaniem NP-PLC i RP-PLC. Dla produktu o określonej czystości, porównano maksymalny stopień przeładowania kolumny, efektywność procesu wyrażoną jako ilość substancji otrzymanej w jednostce czasu oraz produktywność kolumny, wyrażoną jako...
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Quantification of DNA Modifications Using Two-Dimensional Ultraperformance Liquid Chromatography Tandem Mass Spectrometry (2D-UPLC-MS/MS)
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Steroid profiles as potential biomarkers in patients with urogenital tract cancer for diagnostic investigations analyzed by liquid chromatography coupled to mass spectrometry
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Determination of PCBs in marine sediment using pressurised liquid extraction-gas chromatography-isotope dilution mass spectrometry -method validation
PublicationOpracowano procedurę oznaczania wybranych analitów z grupy PCB w próbkach osadu dennego z wykorzystaniem techniki przyspieszonej ekstrakcji za pomocą rozpuszczalnika (PLE) w połączeniu z chromatografią gazową z detektorem spektrometrii mas. Opracowana procedura analityczna została wykorzystana do analizy próbek morskiego osadu dennego, które stanowiły przedmiot badań międzylaboratoryjnych organizowanych przez Comité Consultatif...
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Determination of robenidine in animal feeds by liquid chromatography coupled with diode-array detection and mass spectrometry after accelerated solvent extraction
PublicationRobenidyna (chlorowodorek 1,3-bis[(4-chlorobenzylideno)amino]guanidyny) jest stosowana w celu zapobiegania i leczenia kokcydiozy - pasożytniczej choroby układu pokarmowego wielu zwierząt hodowlanych (kozy, owce, króliki, drób) wywoływanej przez pierwotniaki należące do rzędu Eimeria tenella, E. Necatrix, E. Acervulina, E. Maxima, E. Brunetti, and E. Mivati. Robenidyna wykazuje stosunkowo wysoką skuteczność terapeutyczną, przy niewielkiej...
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Sensitive simultaneous determination of 19 fluorobenzoic acids in saline waters by solid-phase extraction and liquid chromatography–tandem mass spectrometry
PublicationA solid-phase extraction (SPE) procedure using C18 stationary phase was optimized for the preconcentration of 19 fluorinated derivatives of benzoic acid (FBA): mono-, di-, tri-, and tetrafluorosubstituted in the ring, trifluoromethylbenzoic acid and 3,5-bistrifluoromethyl benzoic acid from undiluted salt-rich (>20%) reservoir waters. Quantitative (>90%) retention/elution of 16 out of 19 analyte compounds was achieved allowing a...
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Analysis of chiral pharmaceutical residues in influent and effluent samples at racemic and enantiomeric level using liquid chromatography-tandem mass spectrometry
PublicationIn this work, two different chromatographic methods for seasonal monitoring of pharmaceutical residue in wastewater samples were developed. In the case of enantiomeric separation of selected compounds, LC-MS technique combining with vancomycin based chiral stationary phase was used. The performance of chiral analysis enabled to monitor the pharmaceutical contamination at the enantiomeric level. The d-SPE procedure was developed...
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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
PublicationThe 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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Determination of amikacin and ciprofloxacin by liquid chromatography with pre-column derivatization to evaluate sustained delivery of antibiotics from Drug-Eluting Biopsy Needle
PublicationDetermination of chosen antibacterial antibiotics: amikacin and ciprofloxacin was carried out by HPLC-UV after derivatization with 9-fluorenylmethyl chloroformate and in their native form by HPLC-MS/MS. Developed methods have been applied to control the kinetics of antibiotic release from polymer-based controlled drug delivery system.
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Ultrasound assisted solvent extraction of porous membrane-packed samples followed by liquid chromatography-tandem mass spectrometry for determination of BADGE, BFDGE and their derivatives in packed vegetables
PublicationThe problem of the presence of trace organic pollutants in food is of growing importance due to increasing awareness about their impact on newborns, infants and adults of reproductive age. Despite the fact that packaged food products offer many advantages, packaging can be a source of contamination for stored food. Thus, monitoring such pollution in food is of high importance. In this work, a novel methodology based on the solvent...
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Occurrence and seasonal variations of 25 pharmaceutical residues in wastewater and drinking water treatment plants
PublicationThousands of tons of pharmaceuticals are introduced into the aqueous environment due to their incomplete elimination during treatment process in wastewater treatment plants (WWTPs) and water treat- ment plants (WTPs). The presence of pharmacologically active compounds in the environment is of a great interest because of their potential to cause negative effects. Furthermore, drugs can undergo different pro- cesses leading to the...
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Convenient identification of desulfoglucosinolates on the basis of mass spectra obtained during liquid chromatography-diode array-electrospray ionisation mass spectrometry analysis: Method verification for sprouts of different Brassicaceae species extracts
PublicationOver the past decade, glucosinolates (GLs) present in different tissues of Brassicaceae and their breakdown products, especially isothiocyanates formed after myrosinase catalyzed hydrolysis, have been regarded as not only environment friendly biopesticides for controlling soilborne pathogens, but most importantly as promising anticarcinogenic compounds. For these reasons, the identification and quantitative determination of the...
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Comparison of hydrophilic interaction and reversed phase liquid chromatography coupled with tandem mass spectrometry for the determination of eight artificial sweeteners and common steviol glycosides in popular beverages
PublicationHydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MS/MS) was used to separate artificial and natural sweeteners approved for use in European Union (EU). Among three tested HILIC columns (BlueOrchid PAL-HILIC, Ascentis Express Si and Acclaim™ Trinity™ P2) the last one was selected for the development of HILIC method due to the best results obtained with it. Early eluting and coeluting compounds...
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Novel liquid chromatography method based on linear weighted regression for the fast determination of isoprostane isomers in plasma samples using sensitive tandem mass spectrometry detection
PublicationA simple, fast, sensitive and accurate methodology based on a LLE followed by liquid chromatography–tandem mass spectrometry for simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in routine analysis of human plasma samples was developed. Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the...
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Least absolute shrinkage and selection operator and dimensionality reduction techniques in quantitative structure retention relationship modeling of retention in hydrophilic interaction liquid chromatography
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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)
PublicationThe 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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Structure and Stability Characterization of Natural Lake Pigments Made from Plant Extracts and Their Potential Application in Polymer Composites for Packaging Materials
PublicationNatural 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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Characterization of GM3 Gangliosides in Human Milk throughout Lactation: Insights from the Analysis with the Use of Reversed-Phase Liquid Chromatography Coupled to Quadrupole Time-Of-Flight Mass Spectrometry
PublicationGangliosides are complex lipids found in human milk that play important structural and biological functions. In this study, we utilized reversed-phase liquid chromatography coupled to quadrupole time-of-flight mass spectrometry to evaluate the molecular distribution of GM3 in human milk samples collected at distinct lactation stages, ranging from colostrum to advanced lactation samples. Throughout lactation, GM3 d40:1 emerged as...
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Rapid ion-exchange matrix removal for a decrease of detection limits in the analysis of salt-rich reservoir waters for fluorobenzoic acids by liquid chromatography coupled with tandem mass spectrometry
PublicationA matrix removal procedure with ion-exchange resin prior to analysis for 18 fluorinated benzoic acids (FBAs) tracers in saline (>25% salt) reservoir water was optimized. The elimination of >98% of salt and the simultaneous matrix sample cleanup allowed the direct analysis using the supernatant by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This resulted in a gain in detection limits for most of the tracers...
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Optimisation of pressurised liquid extraction for elimination of sulphur interferences during determination of organotin compounds in sulphur-rich sediments by gas chromatography with flame photometric detection
PublicationOpracowano metodę analizy osadów dennych na zawartość związków cynoorganicznych (MBT, DBT, TBT, MPhT, DPhT, TPhT) przy użyciu przyspieszonej ekstrakcji rozpuszczalnikiem i chromatografii gazowej z detektorem płomieniowo-fotometrycznym. Detektor ten pozwala selektywnie wykrywać niewielkie ilości pochodnych cynoorganicznych. Niestety, bardzo często spotykana w osadach siarka oraz jej pochodne zakłócają sygnał detektora. Z tego względu...
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Using pattern recognition entropy to select mass chromatograms to prepare total ion current chromatograms from raw liquid chromatography–mass spectrometry data
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Silica-Based Ionogels: Nanoconfined Ionic Liquid-Rich Fibers for Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Barrier Discharge Ionization Detection
PublicationIn this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol–gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive...
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Determination of bromhexine and its metabolites in equine serum samples by liquid chromatography – Tandem mass spectrometry: Applicability to the elimination study after single oral dose
PublicationBromhexine (BH), expectorant used in the treatment of respiratory disorders associated with viscid or excessive mucus, is not permitted for use in the competing horse by many authorities in horseracing and Olympic disciplines. Metabolic studies are of the great importance in anti-doping field because they allow for updating the selection of the most appropriate markers for prohibited substances, such as metabolites present at higher...
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Dispersive solid-phase extraction using multi-walled carbon nanotubes combined with liquid chromatography–mass spectrometry for the analysis of β-blockers: Experimental and theoretical studies
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