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Determination of phenylbutazone, sulfamethazine, carbendazim and linuron using a novel pine bark biosorbent for solid-phase extraction (SPE) with high-performance liquid chromatography (HPLC)
PublikacjaThe paper presents a novel pine bark based biosorbent for solid-phase extraction (SPE). The morphology and composition of the pine bark were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The biosorbent was used for the preparation of wastewater for the determination of phenylbutazone, sulfamethazine, carbendazim, and linuron by high performance liquid chromatography with...
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Multivariate Optimization of the FLC-dc-APGD-Based Reaction-Discharge System for Continuous Production of a Plasma-Activated Liquid of Defined Physicochemical and Anti-Phytopathogenic Properties
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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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Suitability of biomass from waste wood composites for liquid biofuel production Możliwość wykorzystania biomasy poużytkowych tworzyw drzewnych w technologii ciekłych biopaliw
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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
PublikacjaOpracowano 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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Optimal conditions of ramentaceone and plumbagin separation and isolation from carnivorous plants extracts using reverse phase-high performance liquid chromatography (RP-HPLC)
PublikacjaPreparatywna chromatografia cieczowa jest szczególnie przydatną techniką do rozdzielania i izolacji użytecznych ilości substancji z różnych skomplikowanych mieszanin. Praca prezentuje optymalne warunki rozdzielania i izolacji ramentaceonu i plumbaginy uwzględniając maksymalną selektywność rozdzielania naftochinonów od substancji balastowych z chloroformowych ekstraktów roślinnych D. aliciae i D. capensis z zastosowaniem techniki...
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Optimal conditions of ramentaceone and plumbagin separation and isolation from carnivorous plants extracts using normal phase-high performance liquid chromatography (NP-HPLC)
PublikacjaPraca prezentuje optymalne warunki rozdzielania i izolacji plumbaginy i ramentacenu z matrycy analitycznej, którą stanowią chloroformowe ekstrakty z roślin D.aliciae i D.capensis z wykorzystaiem techniki NP-HPLC. Skład eluentu dla żelu krzemionkowego jako fazy stacjonarnej był optymalizowany. Zostały przedstawione optymalne warunki powiększania skali procesu izolacji badanych metabolitów z ekstrakrów roślinnych. Określono również...
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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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Modelowanie procesów oscylacyjnych w układach z membraną ciekłą i kationowym surfaktanetm = Modeling of oscillation processes in systems with liquid membrane and cationic surfactant
PublikacjaBadano mechanizm oscylacji róznicy potencjału elektrycznego między fazami wodnymi trójfazowego układu z membraną ciekłą zawierającą kwas pikrynowy rozpuszcony w nitrobenzenie. Wodna faza donorowa zawierała kationowy surfaktant (bromek heksadecylotrimetyloamoniowy) i etanol. Faza akceptorowa składała się z wodnego roztworu sacharozy. Mechanizm sugeruje, że gwałtowna adsorpcja i desorpcja surfaktantu na granicy fazy akceptorowej...
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Rozróznianie substancji odpowiedzialnych za wrażenia smakowe za pomocą oscylatorów z membraną ciekłą.Recognition of substances responsible for taste by using liquid membrane oscillators.
PublikacjaOtrzymano krzywe oscylacyjne oscylatorów z membraną ciekłą zawierających anionowy (oleinian sodu) lub kationowy (chlorek brnzylodimetylotetradecyloamoniowy) surfaktant i substancje należące do czterech podstawowych klas samaku (słony, słodki, kwaśny i gorzki). Dla każdego przypadku zrekonstuowano portrety fazowe metodą opóźnienia czasowego. Stwierdzono, iż oscylatory z kationowym surfaktantem wydają sie byż korzystniejsze do rozróżniania...
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‘Green’ multi - residue methods for the determination of high importance currently used pesticides in environmental samples
PublikacjaThe purpose of the research has been to develop and apply ‘green’ analytical methodologies to control and monitor the level of currently used pesticides from different chemical groups in aqueous samples. For extraction of analytes solid - phase microextraction (SPME) and dispersive liquid - liquid microextraction (DLLME) have been applied and compared. For SPME, commonly used materials for coating fibers include: polydimethylsiloxane...
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Roxithromycin-loaded lipid nanoparticles for follicular targeting
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Developments in Green Chromatography
PublikacjaGreen analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents...
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How Do Ionic Liquids Affect the Surface Structure of Titania Photocatalyst? An Electron-Trap Distribution-Analysis Study
PublikacjaTitanium(IV) oxide, titania, photocatalyst particles were prepared from titanium alkoxide in the presence of several kinds of ionic liquids, and it was clarified that a group of samples exhibited photocatalytic activity for phenol degradation under the irradiation of light of wavelength >400 nm higher than those of the other group of samples. Although the conventional structural analytical results could not be related to the activity,...
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User-assisted methodology targeted for building structure interpretable QSPR models for boosting CO2 capture with ionic liquids
PublikacjaTask-specific ionic liquid (IL) is an emerging class of compounds that may be environmentally friendly. Properly selected, these compounds may be green alternative to amine solutions and can replace them in post-combustion carbon dioxide (CO2) capture processes on an industrial scale. However, owing to the vast diversity of ions and their possible combinations, laboratory research is time consuming and expensive. Therefore, computational...
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How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies
PublikacjaIonic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation...
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Dual functionality of amphiphilic 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids: surfactants with catalytic function
PublikacjaA series of amphiphilic 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids were synthesized. Acidic hydrogen sulfate ionic liquids with the alkyl chains C6–C14 are characterized by good surface properties. Their surface properties (adsorption and micellization parameters, degree of ionization of micelles, Krafft temperatures and thermodynamic parameters) were determined. Synthesized ionic liquids were applied as a co-catalyst...
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Enhanced extraction of proteins using cholinium-based ionic liquids as phase-forming components of aqueous biphasic systems
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Preliminary study on suitability of ionic liquids as potential passive-sampling media of polyaromatic-hydrocarbon (PAH) analyses in water
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Characteristic of Morpholinium Ionic Liquids as Gas Chromatography Stationary Phases with McReynolds Constants and Activity Coefficients at Infinite Dilution
PublikacjaIn this work, four ionic liquids based on N-alkyl-N-methylmorpholinium cation ([Mor1,R] where R= 2, 4, 8, 10) and bis(trifluoromethanesulfonyl)imide anion [TFSI] were synthesized. Using gas-liquid chromatography a number of parameters describing the sorption properties of the investigated ionic liquids were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis...
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Determination of the adsorption mechanism of imidazolium type ionic liquids onto kaolinite: implications for their fate and transport in the soil environment
PublikacjaNiniejsza publikacja szczegółowo opisuje sorpcję cieczy jonowych na powierzchni glin kaolinowych. Uzyskane wyniki wskazują na występowanie zjawiska sorpcji wielowarstwowej. Przy całkowitym wysyceniu najwyższy współczynnik podziału został zaaobserwowany dla cieczy jonowych podstawionych długim łańcuchem alkilowym. Średnie wartości energii swobodnej wyznaczone dla procesu sorpcji cieczy jonowych są niższe niż typowe energie swobodne...
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Ionic liquids: predictions of physicochemical properties with experimental and/or DFT-calculated LFER parameters to understand molecular interactions in solution
PublikacjaPublikacja zawiera modele pozwalające na przewidywanie współczynnika podziału oktanol-woda (log P), rozpuszczalności w wodzie oraz krytycznego stężenia micelizacji (CMC) cieczy jonowych oraz współczynników aktywności anionowej i hydrofobowości w wodzie i w mieszaninie oktanolu z wodą. Modele oparte są na liniowych zależnościach energii swobodnej (LFER) i wykorzystują parametry zmierzone i/lub wyliczone na podstawie funkcjonalnej...
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Enzymatic Polymerization of Cyclic Monomers in Ionic Liquids as a Prospective Synthesis Method for Polyesters Used in Drug Delivery Systems
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Solvation of ionic liquids based on N-methyl-N-alkyl morpholinium cations in dimethylsulfoxide – volumetric and compressibility studies
PublikacjaThe density and sound velocity of the solutions of ionic liquids based on N-alkyl-N-methyl-morpholinium cations, N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-butyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, N-methyl-N-octyl-morpholinium bis(trifluoromethanesulfonyl)imide and N-decyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide in dimethylsulfoxide were measured at T = (298.15 to 318.15)...
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Influence of temperature and anion type on thermophysical properties of aqueous solutions of morpholine based amino acid ionic liquids
PublikacjaDensities and sound velocities of aqueous solutions of N-butyl-N-methylmorpholine based amino acid ionic liquids (AAILs), including N-acetyl-L-alanine, N-acetyl-Lvalinate, N-acetyl-L-leucinate, and N-acetyl-L-izoleucinate anions were measured at a temperature from 293.15 to 313.15 K at 5 K intervals and atmospheric pressure. These data were used to calculate the apparent molar volumes and the apparent molar compressibilities in...
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Hydrophobic deep eutectic solvents as “green” extraction media for polycyclic aromatic hydrocarbons in aqueous samples
PublikacjaThe paper presents novel nonionic and hydrophobic deep eutectic solvents which were synthesized from natural compounds, i.e., thymol, ±camphor, decanoic and 10-undecylenic acids. Fundamental physicochemical properties of the synthesized deep eutectic solvents were determined, followed by their application as extractants in ultrasound-assisted dispersive liquid-liquid microextraction to isolate and enrich polycyclic aromatic hydrocarbons...
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Characterization of home-made and regional fruit wines by evaluation of correlation between selected chemical parameters
PublikacjaSince the last decade of the 20th century, there has been rising interest in the production of fruit wines, as evidenced by the high number of published papers and books covering this matter. When aiming to produce quality fruit wines, it is essential to evaluate the analytical parameters of the beverage. In this context, there are a large number of analyses for the evaluation of wines and fruit wines. This article characterizes...
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Comparison of mouse plasma and brain tissue homogenate sample pretreatment methods prior to high-performance liquid chromatography for a new 1,2,4-triazole derivative with anticonvulsant activity
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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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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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Production of antimicrobial silver nanoparticles modified by alkanethiol self‐assembled monolayers by direct current atmospheric pressure glow discharge generated in contact with a flowing liquid anode
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Flowing Liquid Anode Atmospheric Pressure Glow Discharge as an Excitation Source for Optical Emission Spectrometry with the Improved Detectability of Ag, Cd, Hg, Pb, Tl, and Zn
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Comparison of the performance of direct current atmospheric pressure glow microdischarges operated between a small sized flowing liquid cathode and miniature argon or helium flow microjets
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Direct current atmospheric pressure glow discharge generated between a pin-type solid cathode and a flowing liquid anode as a new tool for silver nanoparticles production
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Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive Part II Mechanical losses in a pump
PublikacjaŚciśliwość cieczy roboczej może znacząco zmienić wartości i proporcje współczynników strat objętościowych i mechanicznych w pompie wyporowej zastosowanej w układzie napędu hydrostatycznego. Wpływ ten jest szczególnie widoczny w trakcie pracy pod wysokim ciśnieniem a także wówczas, gdy występuje zapowietrzenie cieczy roboczej. W części II przedstawiono model matematyczny momentu strat mechanicznych w pompie oraz jego laboratoryjną...
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Toxicity of ionic liquid cations and anions towards activated sewage sludge organisms from different sources – Consequences for biodegradation testing and wastewater treatment plant operation
PublikacjaIonic liquids (ILs) have attracted great interest in academia and industry during the last decade. So far, several ILs have been used in technological processes, from small scale to industrial applications, which makes it more and more likely that they will be released into the environment. Researches have been actively studying the environmental and toxicological bevaviour of ILs, but their influence on the activated sewage sludge...
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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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Determination of eight artificial sweeteners and common Stevia rebaudiana glycosides in non-alcoholic and alcoholic beverages by reversed-phase liquid chromatography coupled with tandem mass spectrometry.
PublikacjaThe method for the determination of acesulfame-K, saccharine, cyclamate, aspartame, sucralose, alitame, neohesperidin dihydrochalcone, neotame and five common steviol glycosides (rebaudioside A, rebaudioside C, steviol, steviolbioside and stevioside) in soft and alcoholic beverages was developed using high-performance liquid chromatography and tandem mass spectrometry with electrospray ionisation (HPLC-ESI-MS/MS). To the best of...
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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
PublikacjaA 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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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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Nowoczesne metody termochemicznej konwersji biomasy w paliwa gazowe, ciekłe i stałe = Modern methods of thermochemical biomass conversion into gas, liquid and solid fuels
PublikacjaBiomass utilization through direct- or co-combustion with coal, based on coal, hydrogen and oxygen compounds chemical energy conversion into heat in boilers, is simultaneously the cheapest and - according to experts - economically least effective solution. In case of heat and electricity production in cogeneration process in biomass fueled heat and power stations (wood, straw, energetic plants, RDF etc), investment costs are little...
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Nowe rozwiązania metodyczne i techniczne w zakresie techniki mikroekstrakcji do fazy stracjonarnej
PublikacjaSample preparation has been recognized as a critical step of the analytical process, being even considered as the bottleneck of the overall process. Enrichment of target compounds, transfer of the analytes into a solvent compatible with the analytical instrumentation, minimization of potential interferences, and efficient sample clean-up, are among the main aims of sample preparation techniques. In this regard, liquid-liquid extraction...
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Positron Scattering and Annihilation in Organic Molecules
PublikacjaIn this paper, we address the problem of connecting positron lifetimes in liquids with collision cross sections in gases. We present the analyses of annihilation lifetime spectra of positrons in the liquid benzene, c-hexane, n-hexane, methanol and ethanol and calculations of scattering cross sections of positrons with benzene and c-hexane in the gas phase.
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Five years of innovations in development of glow discharges generated in contact with liquids for spectrochemical elemental analysis by optical emission spectrometry
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Evaluation of Gas Chromatography Stationary Phases Based on Morpholinium Ionic Liquids by McReynolds Constants and Activity Coefficients at Infinite Dilution
PublikacjaIn this work, four ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium cation ([Mor1,R], in which R = 2, 4, 8, or 10) and bis (trifluoromethanesulfonyl)imide anion were synthesized. Using GLC, a number of parameters describing the sorption properties of the investigated ILs were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis for the evaluation...
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Apparent Molar Volumes and Isentropic Compressibilities of Tetraalkylammonium Bromides in Aqueous Propane-1,2-diol. An Attempt to Design Hydraulic Liquids
PublikacjaApparent molar volumes and apparent molar compressibilities for tetramethylammonium, tetraethylammonium, tetrapropylammonium, and tetrabutylammonium bromides in water, propane-1,2-diol, and water−propane-1,2-diol mixtures (mass fraction: 0.25, 0.50, and 0.75) have been determined from solution density measurements at T = 288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15 K and sound velocity measurements at T = 298.15 K...
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Cations of amino acid alkyl esters conjugated with an anion from the group of NSAIDs – As tunable pharmaceutical active ionic liquids
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New procedure for the control of the treatment of industrial effluents to remove volatile organosulfur compounds
PublikacjaWe present a new procedure for the determination of volatile organosulfur compounds in samples of industrial effluents using dispersive liquid–liquid microextraction and gas chromatography with flame photometric detection. Initially, the extraction parameters were optimized. These included: type and volume of extraction solvent, volume of disperser solvent, salting out effect, pH, time and speed of centrifugation as well as extraction...
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Evaluation of the Impact of Storage Conditions on the Biogenic Amines Profile in Opened Wine Bottles
PublikacjaA survey of biogenic amine (BA) profiles in opened wine bottles has been established to monitor the level of biogenic amines (BAs) in opened bottles against time and other conditions. Bottles of red and white wine were submitted to different temperatures, stopper type (screw cap, cork), and use of vacuum devices. A total of six wines made from a variety of grapes were obtained from vineyards from regions across Poland. Dispersive...
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Optimization of a Fabric Phase Sorptive Extraction protocol for the isolation of six bisphenols from juice pouches to be analysed by high performance liquid chromatography coupled with diode array detector
PublikacjaFabric Phase Sorptive Extraction (FPSE) combined with high pressure liquid chromatography using to diode array detection (HPLC-DAD) was applied for the simultaneous determination of bisphenols (BPA, BPB, BPC, BPE, BPF, BPS) in juice pouches. The FPSE procedure was optimized with regards to the critical parameters that affect the performance of the method including the selection of the FPSE membrane type and size, adsorption time,...