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Analysis of essential oils through comprehensive two-dimensional gas chromatography: General utility
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Headspace Liquid-Phase Microextraction of Chlorobenzenes in Soil with Gas Chromatography-Electron Capture Detection
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Separation of anthocyanins from black carrot, chokeberry, blackcurrant, and elderberry with the use of preparative chromatography
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Characterization of In Vitro and In Vivo Metabolism of Antazoline Using Liquid Chromatography-Tandem Mass Spectrometry
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pH Gradient as a Tool for the Separation of Ionizable Analytes in Reversed-Phase High-Performance Chromatography
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Can Immobilized Artificial Membrane Chromatography Support the Characterization of Antimicrobial Peptide Origin Derivatives?
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Development and evaluation of headspace gas chromatography method for the analysis of carbonyl compounds in spirits and vodkas
PublikacjaPrzedstawiono wyniki oznaczania związków karbonylowych (po przeprowadzeniu w pochodne przy użyciu odczynnika derywatyzującego - o-PFBHA) przy wykorzystaniu techniki analizy fazy nadpowierzchniowej w połączeniu z chromatografią gazową i detektorem wychwytu elektronów(ECD). Przedstawiono optymalizację metodyki oraz wyniki uzyskane podczas próbek rzeczywistych wybranych wyrobów spirytusowych.
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Determination of solvents residues in vegetable oils and pharmaceuticals by headspace analysis and capillary gas chromatography.
PublikacjaPrzedstawiono wyniki zastosowania techniki analizy fazy nadpowierzchniowej w połączeniu z kapilarną chromatografią gazową do oznaczania wybranych rozpuszczalników organicznych w próbkach olejów jadalnych i produktów farmaceutycznych. Oznaczane rozpuszczalniki to: benzen, toluen, heksan oraz chlorowcopochodne węglowodorów alifatycznych. Opracowaną procedurę poddano walidacji. Wyznaczono granicę wytrzymalności, oznaczalności, liniowość...
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Application of static headspace gas chromatography for routine analysis of VFAs in cattle farm wastewater
PublikacjaOznaczanie lotnych kwasów tłuszczowych w próbkach środowiskowych jest tematem coraz powszechniej analizowanym z uwagi na ich uciążliwość w środowisku. Celem pracy było wykorzystanie techniki statycznej analizy headspace (HS) w połączeniu z analizą chromatograficzną do oznaczania lotnych kwasów monokarboksylowych w wodnych próbkach środowiskowych pochodzących z hodowli bydła.
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Comparison of Ion Chromatography and Isotachophoresis for the Determination of selected Anions in Atmospheric Wet Deposition Samples
PublikacjaW pracy przedstawiono porównanie wyników oznaczenia zawartości wybranych anionów w próbkach opadów atmoferycznych z zastosowaniem technik izotachoforezy i chromatografii jonowej. Na podstawie otrzymanych wyników można stwierdzić, że technika chromatografii jonowej charakteryzuje się niższymi wartościami granic wykrywalności i oznaczalności, szerokim zakresem pomiarowym i możliwością oznaczania analitów w próbkach o róznym składzie...
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Evaluation of the usefulness and optimization of the separation conditions in Empty Column Gas Chromatography (EC-GC)
PublikacjaDotychczasowe badania wykazały, że możliwe jest rozdzielanie wysokowrzących mieszanin techniką chromatografii gazowej z zastosowaniem pustej rurki kapilarnej z topionej krzemionki, zamiast kolumn zawierających fazę stacjonarną. Operacja rozdzielania chromatograficznego ma miejsce jedynie na zasadzie różnicy temperatur wrzenia rozdzielanych substancji. Wysoki stopień podobieństwa warunków rozdzielania, osiąganych w ten sposób, z...
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Recent theoretical and practical applications of micellar liquid chromatography (MLC) in pharmaceutical and biomedical analysis
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Improved chromatography separation for polybrominated diphenyl ether congeners quantification in the food of animal origin
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Troubleshooting of the determination of bisphenol A at ultra-trace levels by liquid chromatography and tandem mass spectrometry
PublikacjaDetermination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observations (i.e., poor repeatability of results)...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublikacjaIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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Determination of cyanide ion in urine samples using ion chromatography with pulsed amperometric detection.
PublikacjaCyanides are widely applied in industrial activity, including gold and silver mining and the production of organic chemicals. HCN is also formed directly from fossil fuel combustion sources from gasoline and diesel vehicles. In natural environment, in plants seeds for example an apple seed, it exists as a cyanogenic glycosides. The amount of cyanide ions originating from food products is however rather small. Larger concentrations...
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Application of micellar electrokinetic chromatography for detection of silver nanoparticles released from wound dressing
PublikacjaThe recent emergence of nanotechnology has provided a new therapeutic modality in case of silver nanoparticles. Dressings containing silver form the basis for the treatment of burns and wounds, either acute or chronic ones. The aim of the study was to examine silver release from the different wound dressings: commercially available (Atrauman Ag, Aqua- cel Ag) and experimental (FKDP-AgNPs) using MEKC. In order to characterize prepared keratin...
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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
PublikacjaBromhexine (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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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublikacjaSalting-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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Human Adipose-Derived and Amniotic Fluid-Derived Stem Cells: A Preliminary In Vitro Study Comparing Myogenic Differentiation Capability
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publikacja: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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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
PublikacjaGangliosides 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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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
PublikacjaBased 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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Application and optimization of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography - flame-ionization detector (GC-FID) to determine products of the petroleum industry in aqueous samples
PublikacjaA simple and solvent-free analytical method has been optimized for the determination of hydrocarbons (C6 - C20) from products of the petroleum industry in aqueous samples. Extraction and analysis was carried out using headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled with flame-ionization detector (GC-FID). A ZB-5 capillary column (30 m × 0.25 mm inner diameter, 0.25 µm film thickness) was used for...
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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
PublikacjaA 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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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
PublikacjaThe 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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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
PublikacjaHydrophilic 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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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
PublikacjaBisphenol 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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The study of salting-out thin-layer chromatography and their application on QSRR/QSAR of some macrolide antibiotics
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Quantitative determination of diazepam, nitrazepam and flunitrazepam in tablets using thin-layer chromatography–densitometry technique
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Continuous Monitoring of Thermooxidative Degradation Products of Polystyrene by Membrane Extraction with Sorbent Interface and Gas Chromatography
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A chromatography-free total synthesis of a ferrocene-containing dendrimer exhibiting the property of recognizing 9,10-diphenylanthracene
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Application of gas chromatography-olfactometry (GC-O) in analysis and quality assessment of alcoholic beverages - a review
PublikacjaW ostatnich latach prowadzone są intensywne badania nad aktywnością sensoryczną poszczególnych składników zapachów napojów alkoholowych i nad zależnościami pomiędzy zapachem, a składem chemicznym lotnej frakcji tych produktów z wykorzystaniem techniki chromatografii gazowej z detekcją olfaktometryczną (GC-O). GC-O jest techniką wykorzystującą możliwość oceny sensorycznej eluatu z kolumny chromatograficznej, przy czym dla każdego...
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A comparison of three solvent-free techniques coupled with gas chromatography for determining trihalomethanes in urine samples
PublikacjaDążenie do oznaczania lotnych analitów organicznych w próbkach płynów biologicznych charakteryzujących się złożonym, a często zmiennym składem matrycy, stanowi siłę napędową do działań analityków w zakresie poszukiwania nowych rozwiązań metodycznych i aparaturowych. Publikacja ta przedstawia porównanie trzech technik zastosowanych do tych celów: technikę analizy fazy nadpowierzchniowej z generacją strumienia ciekłego sorbentu...
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Solid phase microextraction combined with chromatography - a powerful tool for determination of warfare agents and related compounds
PublikacjaOpisano zastosowanie mikroekstrakcji do fazy stacjonarnej do izolacji wzbogacania środków bojowych i produktów ich degradacji w powietrzu, wodzie i glebie oraz próbkach bilogicznych. Na etapie oznaczeń końcowych stosuje się najczęściej chromatografię gazową. Anality można pobierać przez bezpośrednie zanurzenie włókna w próbce ciekłej i gazowej oraz w fazie nadpowierzchniowej. Stosując SPME-GC można osiągnąć niskie granice oznaczalności...
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High-performance liquid chromatography in group-type separation and technical or process analytics of petroleum products
PublikacjaW pracy dokonano przeglądu i poddano krytycznej ocenie metody oznaczania składu grupowego produktów naftowych o różnej lotności, zarówno metody znormalizowane, jak i opisane w literaturze naukowej. W zdecydowanej większości są to metody wykorzystujące technikę chromatografii cieczowej w układzie faz normalnych (NP-HPLC). Na podstawie danych z literatury oraz własnych studiów i badań należy stwierdzić, że im wyższy zakres temperatury...
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The Analysis of the distribution of available mesopores in cellulosic pulp, using Inverse Size Exclusion Chromatography-ISEC
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The lipophilicity indices of flavonoids estimated by reversed-phase liquid chromatography using different computation methods
PublikacjaDo 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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Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation
PublikacjaThe main goal of this paper is to discuss the problems associated with antioxidant profiling in complex samples using a high-throughput HPLC system coupled with post-column derivatisation reactor. Based on the experimental data reported in the literature, we demonstrated that improper optimisation of temperature and/or pH assay conditions performed using an on-line derivatisation reactor may substantially change the antioxidant...
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Assessment of blood–brain barrier permeability using micellar electrokinetic chromatography and P_VSA-like descriptors
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Determination of polyphenolics in extracts of Potentilla species by high‐performance thin‐layer chromatography photodensitometry method
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Application of chiral chromatography for enantiomeric separation of currently used pesticides from various chemical groups
PublikacjaChiral pesticides account for more than 25 % of currently used pesticides and this ratio is still increasing. According to the number of chiral centers in the structure, a pesticide may consist of two or multiple enantiomers or stereoisomers. Studies into the stereoselective behaviour of pesticides started in the early 1990s and most research efforts focused on understanding the environmental fate and effects of these pesticides....
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Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublikacjaThe objective of the present study was to measure the concentration of nine high intensity sweeteners (acesulfame-K, aspartame, alitame, cyclamate, dulcin, neohesperidin dihydrochalcon, neotame, saccharin and sucralose) in different types of beverages available on the polish market. The proposed methodology reported here consists of a extraction with buffer composed of formic acid and N,N-diisopropylethylamine (pH 4.5) followed...
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The role of centrifugal partition chromatography in the removal of β-asarone from Acorus calamus essential oil
PublikacjaΒ-asarone is a phenylpropane derivative present in the rhizomes of Acorus calamus, that was proved to exhibit toxic effects in humans. Because of its presence the whole plant that is commonly used in traditional medicine for its sedative, anti-inflammatory, neuroprotective and other properties has limited application nowadays. In the study, qualitative and quantitative analysis of a collection of nine essential oil (EO) samples...
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Comparative Study on Effects of Thermal Gradient Direction on Heat Exchange between a Pure Fluid and a Nanofluid: Employing Finite Volume Method
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Zastosowanie chromatografii cieczowej w odwróconym układzie faz (RP-LC) w rozdzielanie i oznaczaniu polifenoli i naftochinonów w materiałach roslinnychreversed = Phase liquid chromatography (RP-LC) for separation and quantitative determination of polyphenols and naphtoquinones in plant materials
PublikacjaW pracy przedstawiono przegląd metod rozdzielania i oznaczania naftochinonów i polifenoli pochodzących z materiału roślinnego, z wykorzystaniem technik chromatograficznych w układzie faz odwróconych - RP-TLC (Reversed-Phase Thin Layer Chromatography) oraz RP-HPLC (Reversed-Phase High Performance Liquid Chromatography). Przeanalizowano procedury przygotowania próbki, etap rozdzielania, a także kontroli czystości zbieranych frakcji....
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Mechanika płynów, W/L/C, MiBM, sem. 04, letni 21/22 (PG_00050289) Fluid Mechanics
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Sweeping of hydrophobic amines under inhomogeneous electric field and low surfactant concentration in micellar electrokinetic chromatography
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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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