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Search results for: CHROMATOGRAMY
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Novel decahedral TiO2 photocatalysts modified with Ru or Rh NPs: Insight into the mechanism
PublicationNovel decahedral TiO2 modified with Ru or Rh NPs were successfully synthesized by hydrothermal method. The effect of metal type as well as amount of noble metal precursor (0.05, 0.1, 0.2, 0.3 and 0.5 wt.%) on the photocatalytic activity were investigated. Decahedral TiO2 decorated by Ru and Rh nanoparticles was prepared by photodeposition method, whereas Rh doped TiO2 was obtained by onestep hydrothermal method with introduction...
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Electrochemical simulation of metabolic reduction and conjugation reactions of unsymmetrical bisacridine antitumor agents, C-2028 and C-2053
PublicationElectrochemistry (EC) coupled with analysis techniques such as liquid chromatography (LC) and mass spectrometry (MS) has been developed as a powerful tool for drug metabolism simulation. The application of EC in metabolic studies is particularly favourable due to the low matrix contribution compared to in vitro or in vivo biological models. In this paper, the EC(/LC)/MS system was applied to simulate phase I metabolism of the representative...
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THE GENE CLONING, OVEREXPRESSION, PURIFICATION AND BIOCHEMICAL CHARACTERISATION OF A NEW COLD-ADAPTED β–GALACTOSIDASE FROM ARTHROBACTER SP. VII-4
PublicationINTRODUCTION. β-Galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It is commercially used in dairy industry for the production of milk with reduced lactose content. Potentially, the best method for lactose removal under cooling conditions should be carried out with a cold-adapted enzyme. AIM. The aim of this study was to determine the taxonomic affiliation of the isolate...
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B-GALACTOSIDASE ARTHROBACTER SP. 32cB - OBTAINING THE GENE SEQUENCE, CONSTRUCTION OF THE EXPRESSION SYSTEM, BIOSYNTHESIS AND BIOCHEMICAL CHARACTERIZATION OF THE ENZYME
PublicationINTRODUCTION: β-Galactosidase is an enzyme which catalyzes the hydrolysis of O glycosidic bond in β-galactosides. Another activity of β galactosidase is a transglycosylation activity. The main industrial use of this protein is the hydrolysis of lactose in milk in a cooling conditions. Synthesis of galactooligosaccharides, which are mostly used as a prebiotics added to some foods or available as dietary supplements, is only one...
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Screening evaluation of the quality of commercially available cigars, cigarillos, and bidis based on emission levels of selected terpenes and terpenoids
PublicationThe aim of the research was to verify the use of the solvent-free, non-destructive and easy to operate analytical method to study and compare the emissions of 16 representatives of terpenes and terpenoids from commercially available cigars, cigarillos and bidis − a potential screening analysis for the quality of combustible tobacco products. To assess the amount of organic compounds emitted to the gaseous phase from investigated...
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Determination of benzodiazepines and Z-hypnotic drugs in whole blood samples by GC–MS/MS: Method development, validation and application
PublicationBenzodiazepines (BZDs) and Z-drugs are widely used as anxiolytics, sedative hypnotics, anticonvulsants and muscle relaxants. “Designer benzodiazepines” (DBZDs) are a new psychoactive substance class consisting of benzodiazepine derivatives that are not allowed for medical use and are known for being used recreationally. From a toxicologist standpoint, the huge number of such substances implicate a necessity for developing fast...
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Concentrations of monoaromatic hydrocarbons in the air of the underground car park and individual garages attached to residential buildings
PublicationThe paper describes the characteristics of a two-level underground car park and three individual garages attached to residential buildings, differing by the resident utilization habits, located in North Poland (Tri-City agglomeration area). The strategy of collecting the analyte samples from air in mentioned enclosed areas, concerning the determination of benzene, toluene, ethylbenzene, o-xylene and p,m-xylenes (BTEX) concentrations...
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Prediction of Overall In Vitro Microsomal Stability of Drug Candidates Based on Molecular Modeling and Support Vector Machines. Case Study of Novel Arylpiperazines Derivatives
PublicationOther than efficacy of interaction with the molecular target, metabolic stability is the primary factor responsible for the failure or success of a compound in the drug development pipeline. The ideal drug candidate should be stable enough to reach its therapeutic site of action. Despite many recent excellent achievements in the field of computational methods supporting drug metabolism studies, a well-recognized procedure to model...
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TiO2 /SrTiO3 and SrTiO3 microspheres decorated with Rh, Ru or Pt nanoparticles: Highly UV–vis responsible photoactivity and mechanism
PublicationA series of TiO2/SrTiO3 and SrTiO3 microspheres decorated by Rh, Ru or Pt NPs were prepared by facile hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) with energy-dispersive Xray (EDX) spectroscopy, scanning electron microscopy (SEM), photoluminescence spectrometry (PL), Fourier transform infrared (FT-IR) and...
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Interspecific and intraspecific variation in organochlorine pesticides and polychlorinated biphenyls using non-destructive samples from Pygoscelis penguins
PublicationAs humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where...
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A multi‑criteria approach to investigate spatial distribution,sources, and the potential toxicological effect of polycyclic aromatic hydrocarbons (PAHs) in sediments of urban retention tanks
PublicationBottom sediments deposited in retention tanks (RTs) located on two urban streams (Oliwski and Strzyza) in the central part of Gdansk (Poland) were analysed for polycyclic aromatic hydrocarbons’ (PAHs) content. PAHs were extracted from samples with methylene chloride, then the extracts were subjected to clean-up applying the solid phase extraction (SPE) method. Quantitative and qualitative determination of 16 PAHs was performed...
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Determination of the Major By-Products of Citrus hystrix Peel and Their Characteristics in the Context of Utilization in the Industry
PublicationKaffir lime (Citrus hystrix) is a popular citrus in Southeast Asia. Despite the growing interest in the peel of the fruit, the leaves are the most frequently used part of the fruit. The aim of the study was to determine the main by-products of the peel, such as pectins, minerals, essential oil, and bioactive compounds, and to evaluate the possibility of using them in various branches of industry. In the study of the essential oil...
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Seasonal changes of mercury speciation in the coastal sediments
PublicationPurpose Mercury speciation in sediments is linked to environmental conditions and processes. Domination of particular mercury species depends on its source, displays considerable seasonal behavior, and may be further modified due to oxygen levels, icing conditions, or the input of fresh organic matter. The purpose of this study was to examine the coastal area of the Gulf of Gdańsk in terms of mercury contamination and the influence...
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Differences between selected volatile aromatic compound concentrations in sludge samples in various steps of wastewater treatment plant operations
PublicationSewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality...
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Rapid and simple multi-analyte LC–MS/MS method for the determination of benzodiazepines and Z-hypnotic drugs in blood samples: Development, validation and application based on three years of toxicological analyses
PublicationBenzodiazepines (BZDs) and Z-drugs have been particularly important treatments for sleeping and anxiety disorders for many years. However, recently, a number of new benzodiazepines (named designer benzodiazepines, DBZDs) were synthesised, but some of them have never been used in the clinic; they reached the black drug market as new psychoactive substances and are used for recreational purposes. The abuse of these substances has...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES. PART II. ANIONIC COMPOUNDS
PublicationSurfactants (SAA) with negative charge of polar group are named as anionic compounds. They are main constituent of most products containing synthetic surfactants. The linear alkylbenzene sulfonates (LAS), alkyl ethoxysulfates (AES) and alkyl sulfates (AS) are typically applied from this class of compounds. Those surfactants are ingredients of household detergents and cleaners, laundry detergents, cosmetic. Moreover they can be...
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Composition and antimicrobial activity of fatty acids detected in the hygroscopic secretion collected from the secretory setae of larvae of the biting midge Forcipomyia nigra (Diptera: Ceratopogonidae)
PublicationThe hygroscopic secretion produced by the secretory setae of terrestrial larvae of the biting midge Forcipomyia nigra (Winnertz) was analysed using gas chromatography coupled with mass spectrometry (GC-MS). The viscous secretion is stored at the top of each seta and absorbs water from moist air. GC-MS analyses (four independent tests) showed that the secretion contained 12 free fatty acids, the most abundant of which were oleic...
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Simultaneous determination of ibuprofen and its metabolites in complex equine urine matrices by GC-EI-MS in excretion study in view of doping control
PublicationA novel assay for the simultaneous determination of ibuprofen (IBU) and its four probable metabolites, 1-hydroxyibuprofen (1-OH IBU), 2-hydroxyibuprofen (2-OH IBU), 3-hydroxyibuprofen (3-OH IBU) and carboxyibuprofen (CBX IBU) in equine urine samples with the application of Gas Chromatography-Electron Ionization-Mass Spectrometry (GC-EI-MS) has been developed and elaborated. The new approach for sample preparation including minimizing...
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Opracowywanie i porównanie chromatograficznych metodyk oznaczania krótkołańcuchowych kwasów alkanomonokarboksylowych w próbkach wodnych i stałych
PublicationNadrzędnym celem jaki postawiono przy planowaniu programu badawczego będącego podstawą tej rozprawy doktorskiej było opracowanie metodyk oznaczania wolnych krótkołańcuchowych kwasów alkanomonokarboksylowych (KKA) opartych na chromatografii gazowej sprzężonej ze spektrometrią mas lub z detektorem płomieniowo-jonizacyjnym oraz sprawdzenie ich przydatności w analizie wodnych próbek rzeczywistych. Na podstawie przeprowadzonych badań...
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The Action Mechanisms, Anti-Cancer and Antibiotic-Modulation Potential of Vaccinium myrtillus L. Extract
PublicationHerbal medicinal products containing Vaccinium myrtillus L. (bilberry) fruits and fruit extracts are widely available in the market. Although bilberry leaves and stems are considered as bio-waste, they contain much higher levels of phenolic compounds than fruits. The study aimed to investigate the antimicrobial and anticancer potential of aerial part extracts from Vaccinium myrtillus L. (V. myrtillus, VM) plants harvested at high...
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Określenie zawartości lotnych kwasów tłuszczowych (LKT) w odciekach pochodzących z mikrobiologicznej degradacji monosacharydów
PublicationOkreślenie zawartości lotnych kwasów tłuszczowych (LKT) w odciekach pochodzących z mikrobiologicznej degradacji monosacharydów. Milena Jabłońska, Maria Rybarczyk, Marta Wisielewska, Marek Lieder Politechnika Gdańska, Wydział Chemiczny, Katedra Technologii Chemicznej Zawartość lotnych kwasów tłuszczowych (LKT) w metabolitach pochodzących z mikrobiologicznego ogniwa paliwowego (MFC – Microbial Fuel Cell) świadczy o rozkładzie...