Wyniki wyszukiwania dla: GAS CHROMATOGRAPHY
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Controlling the size and morphology of precipitated calcite particles by the selection of solvent composition
PublikacjaCalcium carbonate particles were obtained in the reaction of calcium hydroxide with carbon dioxide at 65°C. Initial Ca(OH)2 suspensions were prepared in pure water and aqueous solutions of ethylene glycol or glycerol of the concentration range up to 20% (vol.). The course of reaction was monitored by conductivity measurements. Precipitated solids were analyzed by FTIR, XRD, SEM and the particles size distribution was determined...
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Divulging the anti-acetylcholinesterase activity of Colletotrichum lentis strain KU1 extract as sustainable AChE active site inhibitors
PublikacjaAlzheimer’s disease (AD), also called senile dementia is a neurodegenerative disease seen commonly in the elderly and is characterised by the formation of β-amyloid plaques and neurofbrillary tangles (NFT). Though a complete understanding of the disease is lacking, recent studies showed the role of the enzyme acetylcholinesterase (AChE) in pathogenesis. Finding new lead compounds from natural sources has always been a quest for...
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Electrochemical and in silico approaches for liver metabolic oxidation of antitumor-active triazoloacridinone C -1305
Publikacja5-Dimethylaminopropylamino-8-hydroxytriazoloacridinone (C-1305) is a promising antitumor compound developed in our laboratory. A better understanding of its metabolic transformations is still needed to explain the multidirectional mechanism of pharmacological action of triazoloacridinone derivatives at all. Thus, the aim of the current work was to predict oxidative pathways of C-1305 that would reflect its phase I metabolism. The...
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Comparative Lipidomic Study of Human Milk from Different Lactation Stages and Milk Formulas
PublikacjaIn this report, we present a detailed comparison of the lipid composition of human milk (HM) and formula milk (FM) targeting different lactation stages and infant age range. We studied HM samples collected from 26 Polish mothers from colostrum to 19 months of lactation, along with FM from seven brands available on the Polish market (infant formula, follow-on formula and growing-up formula). Lipid extracts were analysed using liquid...
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Simultaneous opto-electrochemical monitoring of carbamazepine and its electro-oxidation by-products in wastewater
PublikacjaThe growing human impact on aquatic environments, due to the extensive use of pharmaceuticals and the release of persistent pollutants, makes it necessary to implement new widespread methods for the characterisation and quantification of such contaminants and relative degradation products. Carbamazepine, 5H-dibenzo[b,f]azepine-5-carboxamide, (CBZ) is a widely used anti-epileptic drug, characterised by its limited removal by conventional...
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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
PublikacjaThe 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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Progressing Pollutant Elution from Snowpack and Evolution of its Physicochemical Properties During Melting Period— a Case Study From the Sudetes, Poland
PublikacjaMain aim of the work assumed recognition of physicochemical changes in snowpack occurring during the melting period. Properties of snow cover had been identified at two sites in Western Sudetes mountains (860 and 1228 m asl) in SW Poland since the end of January, and monitored until the disappearance of snow in late Spring. Snow pit measurements and sample collection at both sites were made followed by chemical analyses with the...
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Single-phase product obtained via crude glycerine depolymerisation of polyurethane elastomer: structure characterisation and rheological behaviour
PublikacjaPolyurethane recycling is a topic of growing interest due to the increasing amount of polyurethanewaste. The main purpose of polyurethane feedstock recycling is to recover the starting polyol, a valuable material. In thiswork, amethod of polyurethane thermo-chemical recycling, glycerolysisbymeansof crude glycerine, is proposed. Themaineffort is focusedonthe employment of crude glycerine without purification from biodiesel production...
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Distinction of clenbuterol intake from drug or contaminated food of animal origin in a controlled administration trial – the potential of enantiomeric separation for doping control analysis
PublikacjaThe differentiation of clenbuterol abuse and unintentional ingestion by contaminated meat is crucial with respect to the valuation of an adverse analytical finding in human sports doping control. The proportion of the two enantiomers of clenbuterol may serve as potential discriminating parameter. For the determination of the individual enantiomers, specific methods were developed and validated for the different matrices under investigation...
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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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Ultrasound-Assisted Solvent Extraction of a Porous Membrane Packed Sample for the Determination of Tobacco-Specific Nitrosamines in the Replacement Liquids for E-Cigarettes
PublikacjaThe content of tobacco-specific nitrosamines (TSNAs) possessing carcinogenic properties has been an important area of research since replacement liquids were introduced for e-cigarettes. A method for determining N′-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N′-nitrosoanatabine (NAT), and N′-nitrosoanabasine (NAB) in replacement liquids for electronic cigarettes was developed using liquid chromatography–tandem...
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Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
PublikacjaFor many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional...
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Plant-based meat substitute analysis using microextraction with deep eutectic solvent followed by LC-MS/MS to determine acrylamide, 5-hydroxymethylfurfural and furaneol
PublikacjaFor the analysis of plant-based meat substitutes and the determination of Maillard reaction products such as acrylamide, 5-hydroxymethylfurfural and furaneol, a novel and effective procedure based on hydrophobic natural deep eutectic solvent and liquid chromatography coupled with tandem mass spectrometry was developed for the first time. The 49 compositions of the deep eutectic solvents were designed and screened to select the...
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Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare
PublikacjaLigustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been histori-cally recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from differ-ent morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance...
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Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
PublikacjaA rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean...
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Comparison of classical and modern approach of determination of highly polar compounds by High Performance Liquid Chromatography coupled with Tandem Mass Spectrometry
PublikacjaAbstract: Sugars and sugar alcohols are known as highly polar compounds. Four analytes were taken into consideration for comparison of classical and modern approach of separation of highly polar substances. Mannitol was chosen as an example of simple sugar alcohol, sucrose and lactulose as examples of disaccharides and structural isomers, raffinose as an example of complex trisaccharide. Raffinose was also used as internal standard...
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Phototransformation of Amlodipine: Degradation Kinetics and Identification of Its Photoproducts
PublikacjaNowadays, monitoring focuses on the primary compounds and does not include degradation products formed during various biological and chemical processes. Transformation products may have the same effects to human health and the environment or sometimes they can be more toxic than the parent compound. Unfortunately, knowledge about the formation of degradation products is still limited, however, can be very important for the environmental...
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Novel single-stranded DNA-binding proteins from extreme psychrophilic bacterium Psychromonas ingrahamii 37
PublikacjaWe report the identification and characterization of the single-stranded DNA binding protein (SSB) from extreme psychrophilic bacterium Psychromonas ingrahamii 37 (PinSSB) that grows expotentially at -12°C and may well grow at even lower temperatures. PinSSB is one of the largest known bacterial SSB protein consisting 222 amino acid residues with a calculated molecular mass of 25.1 kDa. The analysis by gel filtration chromatography...
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Quality control of cheese samples for the presence of natamycin preservative – A natural deep eutectic solvent (NADES) based extraction coupled with HPLC
PublikacjaA new protocol for the determination of natamycin – an antifungal agent used as a food preservative - in cheese samples – is described. This new method is based on a natural deep eutectic solvent (NADES) green extraction procedure. High-performance liquid chromatography (HPLC) was used for detection and quantification. NADESs with different molar ratios were evaluated for efficient and selective extraction. NADES made of thymol...
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Microwave radiation in the synthesis of urethane prepolymers
PublikacjaThis paper describes the use of microwave radiation in the synthesis of urethane prepolymers in bulk (without solvent). The prepolymers were synthesized using 1,6-hexamethylene diisocyanate (HDI) and poly (ε-caprolactone) diol (PCL) at a molar ratio of 4:1. The reaction was carried out without a catalyst in the reactor with a conventional heating system (oil bath) or in the microwave reactor (MW Reactor NOVA 09) at temperatures...