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Search results for: CHROMATOGRAMY
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“Dilute & Shoot” approach for rapid determination of trace amounts of nicotine in zero-level e-liquids by reversed phase liquid chromatography and hydrophilic interactions liquid chromatography coupled with tandem mass spectrometry-electrospray ionization
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“Dilute & Shoot” approach for rapid determination of trace amounts of nicotine in zero-level e-liquids by reversed phase liquid chromatography and hydrophilic interactions liquid chromatography coupled with tandem mass spectrometry-electrospray ionization
PublicationTwo analytical procedures are proposed where HILIC and RPLC techniques are coupled with tandem mass spectrometry detection for rapid determination of trace amounts of nicotine in zero-level liquids for electronic cigarettes. Samples are prepared on the basis of the approach “dilute & shoot” which makes this important step quick and not complicated. The chromatographic separation was carried out on a Zorbax XDB column (RPLC method)...
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A comparison of three solvent-free techniques coupled with gas chromatography for determining trihalomethanes in urine samples
PublicationDążenie 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
PublicationOpisano 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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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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A chromatography-free total synthesis of a ferrocene-containing dendrimer exhibiting the property of recognizing 9,10-diphenylanthracene
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The application of gradient reversed-phase high-performance liquid chromatography to the pKa and determination of polyprotic analytes
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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 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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Application of chiral chromatography for enantiomeric separation of currently used pesticides from various chemical groups
PublicationChiral 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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Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation
PublicationThe 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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Comprehensive methodology for Staphylococcus aureus lipidomics by liquid chromatography and quadrupole time-of-flight mass spectrometry
PublicationStaphylococcus aureus is a common pathogen known to cause relatively minor infections as well as severe disorders in humans. Although there is fair amount of published data concerning various aspects of its biology, epidemiology, genetics, etc., there is still a scarce amount of data presenting reliable and thorough investigations regarding high-throughput analysis of total S. aureus lipid content. Therefore, the aim of this study...
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A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublicationThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
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Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublicationThe 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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Determination of isoprostanes in exhaled breath condensate samples by liquid chromatography coupled with tandem mass spectrometry
PublicationOxidative stress (OS) is a state of imbalance between continuously generating reactive oxygen species (ROS) during normal cell metabolism and mechanism of detoxifying oxygen radicals through a network of antioxidative enzymes. Isoprostanes are prostaglandin -like substances that are produced in vivo primarily by free radical-induced peroxidation of arachidonic acid. The measurement of isoprostanes in biological fluids and/or tissue...
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A research on the optimal conditions for separation and identyfication of the components from the Droseraceae extracts by column liquid chromatography
PublicationThe isolation of the components with anticipated biological properties i.e. antimicrobial, fungicidal, antioxidant and perhaps anticancer activity is for many years a one of the biggest issues of modern separation science. Their obtaining based on the isolation of the components with the biological activity from in vitro cultured plants by extraction techniques is often more difficult than their production by the chemical synthesis.The...
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High-performance liquid chromatography in group-type separation and technical or process analytics of petroleum products
PublicationW 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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Determination of carbon monoxide, methane and carbon dioxide in refinery hydrogen gases and air by gas chromatography
PublicationW pracy przedstawiono metodę oznaczania śladowych zawartości tlenku węgla, metanu oraz dwutlenku węgla w rafineryjnych gazach wodorowych oraz powietrzu; granica oznaczalności metody wynosi odpowiednio 0,15, 0,15 oraz 0,20 mikro-gram/litr. Zaprezentowano w pracy prostą modyfikację chromatografu gazowego wyposażonego w detektor płomieniowo-jonizacyjny (FID). Zastosowano kolumnę typu PorapakQ, dodatkowo połączono szeregowo z krótką...
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The role of centrifugal partition chromatography in the removal of β-asarone from Acorus calamus essential oil
PublicationΒ-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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Application of gas chromatography-olfactometry (GC-O) in analysis and quality assessment of alcoholic beverages - a review
PublicationW 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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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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Poultry meat freshness evaluation using electronic nose technology and ultra-fast gas chromatography
PublicationTo ensure that chicken meat products are safe to consume, it is important to be able to reliably determine its shelf-life. To assess the applicability of ultra-fast gas chromatography and electronic nose technology in evaluation of poultry, an analysis of the headspace of ground chicken meat samples refrigerated over a period of 7 days was performed. Chemometric techniques were used to mine additional information from a multiparametric...
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Application of gas chromatography–tandem mass spectrometry for the determination of amphetamine-type stimulants in blood and urine
PublicationAmphetamine, methamphetamine, phentermine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) are the most popular amphetamine-type stimulants. The use of these substances is a serious societal problem worldwide. In this study, a method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) with simple and rapid liquid-liquid extraction (LLE)...
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Authenticity Assessment of the "Onisiówka" Nalewka Liqueurs Using Two-Dimensional Gas Chromatography and Sensory Evaluation
PublicationThe “Onisiówka” nalewka liqueur is a regional Polish alcoholic beverage, which is inscribed on the list of regional and traditional products of the Ministry of Agriculture and Rural Development in Poland. It is produced from multiflower honey, black elderberry flower syrup, and spirit. Due to fact that the “Onisiówka” nalewka liqueur has never been investigated, these studies are the foundation for further work on this regional...
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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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Novel analytical method for detection of orange juice adulteration based on ultra-fast gas chromatography
PublicationThe food authenticity assessment is an increasingly important issue in food quality and safety. The application of an electronic nose based on ultra-fast gas chromatography technique enables rapid analysis of the volatile compounds from food samples. Due to the fact that this technique provides chemical profiling of natural products, it can be a powerful tool for authentication in combination with chemometrics. In this article,...
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Study of pH and temperature effect on lipophilicity of catechol-containing antioxidants by reversed phase liquid chromatography
PublicationLipophilicity of selected antioxidant phytochemicals, including flavonoids, phenolic acids and xanthonoids, was determined by reversed phase high performance liquid chromatography with UV detection (RP-HPLC-UV). The analyses run at different temperature and pH conditions in isocratic mode suggested that lipophilicity as distribution coefficient (logD) between aqueous and organic phase decreases with increasing temperature. For...
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Use of pyrolysis and gas chromatography for the determination of acrylic acid concentration in acrylic copolymers containing carboxylic groups
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Effect of sample-preparation methods on the quantification of selected flavonoids in plant materials by high performance liquid chromatography
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Surfactant free fractions of metallic and semiconducting single-walled carbon nanotubes via optimised gel chromatography
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Retention time and peak width in the combined pH/organic modifier gradient high performance liquid chromatography
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Environmental aspects of using gas chromatography for determination of pharmaceutical residues in samples characterized by different composition of the matrix
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Identification of organic acids as potential biomarkers in the urine of autistic children using gas chromatography/mass spectrometry
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Sweeping of hydrophobic amines under inhomogeneous electric field and low surfactant concentration in micellar electrokinetic chromatography
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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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Sensitive determination of isoprostanes in exhaled breath condensate samples with use of liquid chromatography-tandem mass spectrometry
PublicationOxidative stress is the hallmark of various inflammatory lung diseases. Increased concentrations of reactive oxygen species in the lungs are reflected by elevated concentrations of oxidative stress markers in the breath, airways, lung tissue and blood. The aim of this work was to develop a method for the fast measurement of F2 isoprostanes in exhaled breath condensate (EBC) samples using equipment which is nowadays available and...
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Comparison of High Performance Liquid Chromatography Methods with Different Detectors for Determination of Steroid Hormones in Aqueous Matrices
PublicationThis paper presents the development and comparison of procedures for the qualitative and quantitative determination of five estrogenic compounds (17-a-ethynylestradiol, estrone, estradiol, estriol, and progesterone) in drinking water and wastewater samples. Five extraction columns and two disks were tested for their efficiency. The C18 columns were superior on the basis of cost for solid phase extraction of drinking water or sewage....
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Research on the separation properties of empty-column gas chromatography (EC-GC) and conditions for simulated distillation (SIMDIS)
PublicationThe paper presents the results of investigations on new procedures of determination of selected cleaning additives in diesel fuel. Two procedures: one-step analysis using gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS) and a two-step procedure in which normal-phase high-performance liquid chromatography (NP-HPLC) was used for preliminary separation of the additives, were compared. The additive...
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Common methods for the chiral determination of amphetamine and related compounds I. Gas, liquid and thin-layer chromatography
PublicationThis article reviews the most common, useful methods for the chiral determination of amphetamine (AM) and AM-deriveddesigner drugs in different of matrix, including blood, hair, urine, medicaments or standard solutions, taking into considerationarticles published in the past 15 years. We consider chromatographic methods (e.g., gas, liquid, high-performance liquid, and thinlayer). We describe several types of chiral derivatization...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublicationVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublicationVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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Development of gas chromatography - tandem mass spectrometry procedure for development of pesticide residues in honey and honeybee samples
PublicationA new analytical procedure of determination of multiresidue of pesticides based on application of the modified QuEChERS approach at the step of sample preparation and technique GC-MS/MS has been developed and applied for studies the real honey and honeybee samples. Samples were collected from northern Poland (Pomerania). The proposed procedure enables for the determination of 34 and 30 pesticides residues respectively on honey...
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Application of single drop extraxtion (SDE) gas chromatography method for the determination of carbonyl compounds in spirits and vodkas
PublicationW pracy przedstawiono metodę oznaczania związków karbonylowych w spirytusach i wódkach, wykorzystującą do izolacji i wzbogacania technikę mikroekstrakcji do pojedynczej kropli (SDE)po derywatyzacji analitów O-(2,3,4,5,6-pentafluorobenzylo)hydroksylaminą. Określono optymalne parametry izolacji i wzbogacania aldehydów z roztworów alkoholowych (objętość próbki, objętość kropli, zawartość alkoholu, temperaturę i czas ekstrakcji)....
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Headspace solid-phase microextraction and gas chromatography-olfactometry analysis of raw spirits of different organoleptic quality
PublicationCelem pracy było określenie, ktore związki wnoszą wkład w aromat destylatów rolniczych i wskazać te z nich które mogą powodować obniżenie ich właściwości organoleptycznych. W badaniach zastosowano ekstrakcję lotnych analitów z fazy nadpowierzchniowej techniką mikroekstrakcji do fazy nadpowierzchniowej w połączeniu z chromatografia gazową z detekcja olfaktometryczną . Znaleziono 40 zsubstancji, które mogą być markerami jakości organoleptycznej
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Thermal degradation assessment of canola and olive oil using ultra-fast gas chromatography coupled with chemometrics
PublicationOil blending is often used to enhance the properties of vegetable oils. The admixture of a more thermally stable oil makes the resulting blend more suitable for use in frying. A new method of quality assessment of vegetable oils used in frying is presented in this paper. In this method, ultra-fast gas chromatography coupled with flame ionization detector and chemometrics is employed. Principal component analysis was used for data...