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Nanostructured polyethersulfone nanocomposite membranes for dual protein and dye separation: Lower antifouling with lanthanum (III) vanadate nanosheets as a novel nanofiller
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Optimal conditions of naphthoquinones separation from carnivorous plants extracts using thin-layer chromatography and high performance liquid chromatography
PublikacjaDroseraceae plants are owned by the family of carnivorous plants, which in an unusual way adapt to environments poor in nutrients. Droseraceae obtain essential nutrients catching insects and other small invertebrantes. Plumbagin, chloroplumbagin, ramentaceon and droseron are naphthoquinones, which could be found in leaves and shoots of plants from Droseraceae family. In the literature there are a lot of information about the pharmacological...
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Capillary gas chromatography using a -cyclodextrin forenantiomeric separation of methylamphetamine, its precursors andchloro intermediates after optimization of the derivatization reaction
PublikacjatThe enantiomeric ratio of methylamphetamine (MAMP) is closely related to the optical activity of precur-sors and reagents used for the synthesis and this knowledge can provide useful information concerningthe origins and synthetic methods used for illicit manufacture. The information can be utilized for reg-ulation of the precursors and investigation of the manufacturing sources but this requires analyticalprocedures to determine...
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Musical Instrument Separation Applied to Music Genre Classification . Separacja instrumentów muzycznych w zastosowaniu do rozpoznawania gatunków muzycznych
PublikacjaThis paper outlines first issues related to music genre classification and a short description of algorithms used for musical instrument separation. Also, the paper presents proposed optimization of the feature vectors used for music genre recognition. Then, the ability of decision algorithms to properly recognize music genres is discussed based on two databases. In addition, results are cited for another database with regard to...
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Classification of Music Genres Based on Music Separation into Harmonic and Drum Components . Klasyfikacja gatunków muzycznych wykorzystująca separację instrumentów muzycznych
PublikacjaThis article presents a study on music genre classification based on music separation into harmonic and drum components. For this purpose, audio signal separation is executed to extend the overall vector of parameters by new descriptors extracted from harmonic and/or drum music content. The study is performed using the ISMIS database of music files represented by vectors of parameters containing music features. The Support Vector...
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First deep eutectic solvent-based (DES) stationary phase for gas chromatography and future perspectives for DES application in separation techniques
PublikacjaThe paper presents the first application of deep eutectic solvents (DES) as stationary phases for gas chromatography. DES obtained by mixing tetrabutylammonium chloride (TBAC) as a hydrogen bond acceptor (HBA) with heptadecanoic acid being a hydrogen bond donor (HBD) in a mole ratio of HBA:HBD equal to 1:2 was characterized by its ability to separate volatile organic compounds (VOCs). The Rohrschneider – McReynolds constants determined...
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Combined extraction and microextraction techniques: Recent trends and future perspectives
PublikacjaThe latest advancements in the analytical sample preparation indicate a trend of combining different extraction techniques with targeting an improvement in separation, cleanup, detection limits, enrichment factors, and dealing with complex matrices. This manuscript identifies mainly two groups of combined sample preparation techniques. The first group integrates conventional or enhanced extraction techniques with microextraction....
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Application of molecularly imprinted polymers in analytical chiral separations and analysis
PublikacjaOver the last two decades the process of development and application of a new types of molecular imprinted polymer (MIP) sorbents in the field of analytical chemistry have been widely described in the literature. One of the new trends in analytical chemistry practice is the use of new types of MIP sorbents as specific sorption materials constituting the stationary phase in advanced separation techniques. The following review paper...
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Separation of nitroaromatics and their transformation products in soil around ammunition plants: New high performance liquid chromatographic charge transfer stationary phases
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Separation of nicotinic acid and its structural isomers using 1-ethyl-3-methylimidazolium ionic liquid as a buffer additive by capillary electrophoresis
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Water vapor induced self-assembly of islands/honeycomb structure by secondary phase separation in polystyrene solution with bimodal molecular weight distribution
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Effect of Laminar Pulsatile Fluid Flow on Separation of Volatile Organic Compounds from Aqueous Solution by a Hollow Fiber Membrane-Based Process
PublikacjaIn this study, a laminar pulsatile fluid flow was used for the separation of benzene, toluene, ethylbenzene, and xylene isomers (BTEX) from aqueous solutions. Polyether sulfone hollow fiber membrane has been applied to this process. The effects of BTEX concentration, and feed and extraction flow rates were examined. It was found that the application of the pulsatile fluid flow with...
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The antagonistic role of chaotropic hexafluorophosphate anions and imidazolium cations composing ionic liquids applied as phase additives in the separation of tri-cyclic antidepressants
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Ograniczenie trwałości skojarzeń ceramicznych w wyniku propagacji pęknięć powierzchniowych = Fatigue life limitation of ceramic materials due to surface crack propagation
PublikacjaPrzedstawiono krótką analizę literaturową dotyczącą mechanizmów propagacji pęknięć w materiałach ceramicznych oraz wyniki dotychczasowych badań doświadczalnych wybranych materiałów ceramicznych z uwzględnieniem wpływu pęknięć powierzchniowych na trwałość ceramicznych skojarzeń tocznych.
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Damage detection in 3D printed plates using ultrasonic wave propagation supported with weighted root mean square calculation and wavefield curvature imaging
Publikacja3D printing (additive manufacturing, AM) is a promising approach to producing light and strong structures with many successful applications, e.g., in dentistry and orthopaedics. Many types of filaments differing in mechanical properties can be used to produce 3D printed structures, including polymers, metals or ceramics. Due to the simplicity of the manufacturing process, biodegradable polymers are widely used, e.g., polylactide (polylactide...
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Introduction to MIP synthesis, characteristics and analytical application
PublikacjaOne of the trends in analytical chemistry is associated with designing and developing new types of sample preparation techniques, which might significantly increase the efficiency and selectivity of the analytes isolation or/and preconcentration process. One of the most widely employed solutions are selective sorption materials, defined as molecularly imprinted polymers (MIPs), as well as the sorbents with the molecular fingerprint....
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Pharmaceutical and forensic drug applications of chiral supercritical fluid chromatography
PublikacjaTHE SUPERCRITICAL FLUID IS AN EXCELLENT CHOICE AS THE CHROMATOGRAPHIC MOBILE PHASE BECAUSE IT ALLOWS RAPID SEPARATION WITH HIGH EFFICIENCY AND APPLICATIONS INVOLVING ENANTIORESOLUTION ARE COMMON. SUPERCRITICAL FLUID CHROMATOGRAPHY (SFC) IS INCREASINGLY USED FOR ANALYTICAL, SEMI-PREPARATIVE AND PREPARATIVE PURIFICATION OF CHIRAL COMPOUNDS, INCLUDING PRODUCTION OF ENANTIOMERS THAT ARE MAINLY ENCOUNTERED DURING DRUG DEVELOPMENT. SFC...
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Przydatność białka rybiego w postaci kolagenu lub żelatyny oraz polisacharydu - kapa-karagenu do wytwarzania aktywnych opakowań biodegradowalnych = Usefulness of fish collagen, gelatin and carrageenan for preparation of active biodegradable packages
PublikacjaSummary - The possibility of use of protein films made of fish collagen or gelatin as well as polysaccharide carrageenan films as carriers of enzymes (lysozyme or lysostaphyne), for preparation of microbiologically active packages, was investigated. It was found that crosslinking of such systems with N-[3(dimethylamino)propyl]-N'-ethylcarboimide (EDC) does not influence the activity of lysozyme immobilized in the films (Table 1)....
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Method development and validation for optimized separation of quercetin derivatives in selected Potentilla species using high-performance thin-layer chromatography photodensitometry method
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Nowe metodyki oznaczania dodatków do paliw z zastosowaniem rozdzielenia wielopomiarowego = New procedures for fuel additives determination by multidimensional separation systems
PublikacjaW pracy przedstawiono wyniki badań nad opracowaniem metodyki oznaczania wybranych dodatków "myjących" w paliwie diesla. Porównano metodyki jednoetapowe z wykorzystaniem chromatografii gazowej z detektorem płomieniowo-jonizacyjnym (GC-FID) lub spektrometrem mas (GC-MS) oraz wysokosprawnej chromatografii cieczowej z detektorem UV z matrycą fotodiodową (HPLC-UV-DAD), z metodykami dwuetapowymi, w których do wstępnej izolacji składników...
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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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Performance tuning of chitosan-based membranes by protonated 2-Pyrrolidone-5-carboxylic acid-sulfolane DES for effective water/ethanol separation by pervaporation
PublikacjaToday, the applicability of deep eutectic solvents (DES) in various fields, including membrane science and technology, is extensively investigated. In pioneering works, we have implemented different DES as a component of chitosan (CS)-based flat membranes for pervaporation (PV) separation. Herein, we present a new protonated (by sulphuric acid) 2-Pyrrolidone-5-carboxylic acid: sulfolane DES, as a green additive for its chemical...
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Nowoczesne techniki przygotowania próbki do oznaczania analitów organicznych z zastosowaniem chromatografii gazowej. Część II. Aparatura. Modern techniques of preparation of samples for determining organic analytes by gas chromatography. Part II. Instrumentation.
PublikacjaW pracy dokonano przeglądu szerokiego spektrum technik przygotowania próbki ze szczególnym uwzględnieniem technik o charakterze prośrodowiskowym. Opisu technik dokonano pod kątem wykorzystywanych mechanizmów izolacji analitów oraz stosowanych rozwiązań aparaturowych.
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Acute myocardial infarction reparation/regeneration strategy using Wharton’s jelly multipotent stem cells as an ‘unlimited’ therapeutic agent: 3-year outcomes in a pilot cohort of the CIRCULATE-AMI trial
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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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Automatic music genre classification based on musical instrument track separation / Automatyczna klasyfikacja gatunku muzycznego wykorzystująca algorytm separacji dźwięku instrumentó muzycznych
PublikacjaThe aim of this article is to investigate whether separating music tracks at the pre-processing phase and extending feature vector by parameters related to the specific musical instruments that are characteristic for the given musical genre allow for efficient automatic musical genre classification in case of database containing thousands of music excerpts and a dozen of genres. Results of extensive experiments show that the approach...
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Rapid and Green Separation of Mono- and Diesters of Monochloropropanediols by Ultrahigh Performance Supercritical Fluid Chromatography–Mass Spectrometry Using Neat Carbon Dioxide as a Mobile Phase
PublikacjaThis study demonstrates the effect of column selectivity and density of supercritical carbon dioxide (SC-CO2) on the separation of monochloropropanediol (MCPD) esters, known as food toxicants, using SC-CO2 without addition of cosolvent in ultrahigh performance supercritical fluid chromatography–mass spectrometry (UHPSFC-MS). This study shows that over 20 2-monochloropropanediol (2-MCPD) and 3-monochloropropanediol (3-MCPD) mono-...
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Green chromatography
PublikacjaAnalysis of organic compounds in samples characterized by different composition of the matrix is very important in many areas. A vast majority of organic compound determinations are performed using gas or liquid chromatographic methods. It is thus very important that these methods have negligible environmental impact. Chromatographic techniques have the potential to be greener at all steps of the analysis, from sample collection...
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Analytical procedures for quality control of pharmaceuticals in terms of residual solvents content: Challenges and recent developments
PublikacjaResidual solvents play an important role in the synthesis of drugs and in product formulations. In addition, they pose a serious problem, that is toxicity, as many of them exhibit toxic or environmentally hazardous properties. Therefore, constant monitoring of quality control is needed. In this study, we present an overview of regulatory and general methods described by various pharmacopoeias. Then, the most commonly used methodologies...
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Evaluation of the suitability of low hazard surfactants for the separation of phenols and carotenoids from red-flesh orange juice and olive mill wastewater using cloud point extraction
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Large‐Scale Traveling Ionospheric Disturbances Over the European Sector During the Geomagnetic Storm on March 23–24, 2023: Energy Deposition in the Source Regions and the Propagation Characteristics
PublikacjaMultiple Large-Scale Traveling Ionospheric Disturbances (LSTIDs) are observed in the European sector in both day-time and night-time during the magnetic storm on March 23–24, 2023. The Total Electron Content (TEC) observation from a network of GNSS receivers shows the propagation of LSTIDs with amplitudes between around 0.5 and 1 TECU originating from auroral and polar cusp regions down to southern Europe (35°N) with velocities...
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublikacjaA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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Recent advances on magnetic carbon-related materials in advanced oxidation processes of emerging pollutants degradation
PublikacjaRecently, carbon-related materials have been proposed to improve the charge separation of the photogenerated carriers in the semiconductor matrices’ and surface properties. Carbon-related materials may act as co-catalysts, enhancing the pollutants adsorption on the surface, improving the charge carriers separation and photocatalyst stability and providing more active centres for photocatalytic reactions. This review summarizes...
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Nowoczesne techniki przygotowania próbki do oznaczania analitów organicznych z zastosowaniem chromatografii gazowej. Część I. Podstawy teoretyczne ekstrakcji. Modern techniques of preparation of samples for determining organic analytes by gas chromatography. Part I. Theoretical principles of extraction.
PublikacjaPrzedstawiono podstawy teoretyczne technik izolacji i wzbogacania analitów organicznych z próbek gazowych oraz ciekłych. Już pobieżna analiza literatury dotyczącej omawianych zagadnień, pokazuje jak różnorodne i bogate spektrum technik jest stosowane na etapie przygotowania próbki. Z drugiej strony, z punktu widzenia podstaw fizykochemicznych, większość technik opiera się na dwóch zjawiskach: adsorpcji analitów na medium zatrzymującym...
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The role of solvent solubility parameters in the formation of intermittent low and high molecular weight polystyrene rich structures in a thin film resulting from water vapor induced phase separation
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublikacjaThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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The role of water in deep eutectic solvent-base extraction
PublikacjaDeep eutectic solvents (DESs) are currently being used in different sectors, such as electrochemistry, electrodeposition, organic synthesis, nanoparticle preparation, bioactive compound separation, etc. Their use in analytical chemistry has only recently begun to expand. Despite the publication of a sufficient number of DES-based analytical extraction procedures, some details, such as interaction of DESwith the sample and target...
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Usuwanie lotnych związków organicznych z fazy gazowej z zastosowaniem cieczy jonowych
PublikacjaUżycie cieczy jonowej do usuwania LZO jest limitowane przez rozpuszczalność usuwanych związków. Dane literaturowe sugerują, że ciecze jonowe jako faza membranowa mogą być z powodzeniem stosowane do selektywnej separacji węglowodorów aromatycznych z mieszanin węglowodorów aromatycznych i alifatycznych. Przedmiotem pracy było kompleksowe opisanie procesu separacji LZO z fazy gazowej z uwzględnieniem czynników wpływających na efektywność...
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Chemical Derivatization Processes Applied to Amine Determination in Samples of Different Matrix Composition
PublikacjaAmines are important biological compounds, and so their analysis and monitoring in various matrices is worthy of investigation and development.Due to the polar nature of amines, chromatographic analysis of free amines is generally unsatisfactory owing to adsorption and decomposition of the solute on the column, resulting in peak tailing and losses. Therefore, many derivatization reactions are employed to reduce the polarity, improve...
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Separation and determination of ciprofloxacin in seawater, human blood plasma and tablet samples using molecularly imprinted polymer pipette‐tip solid phase extraction and its optimization by response surface methodology
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The Application of 2,6-Bis(4-Methoxybenzoyl)-Diaminopyridine in Solvent Extraction and Polymer Membrane Separation for the Recovery of Au(III), Ag(I), Pd(II) and Pt(II) Ions from Aqueous Solutions
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Efficient, fast, simple, and eco-friendly methods for separation of toxic chromium(VI) ions based on ion exchangers and polymer materials impregnated with Cyphos IL 101, Cyphos IL 104, or D2EHPA
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Structural changes of bacterial cellulose due to incubation in conditions simulating human plasma in the presence of selected pathogens
PublikacjaBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of medical applications. However, it cannot be used as a biological implant of the circulatory system without checking whether it is biodegradable under human plasma conditions. This work aimed to investigate the BNC biodegradation by selected pathogens under conditions simulating human plasma. The BNC was incubated in simulated biological fluids with or...
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Distillation cleanup preceded gc determination of short-chain monocarboxylic acids in aqueous and solid samples of wastewater origin = Oznaczanie krótkołańcuchowych kwasów monokarboksylowych w próbkach wodnych i stałych pochodzących z oczyszczalni ścieków z wykorzystaniem chromatografii gazowej poprzedzonej destylacją
PublikacjaShort-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work...
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Application of additional factors supporting the microextraction process
PublikacjaDue to the fact that green analytical chemistry is of high importance, the past two decades have witnessed a rapid growth in the sample preparation area with special emphasis on simplification, miniaturization and automation of extraction procedures. In addition, to accelerate the extraction processes and to improve the separation of analytes, several enhanced parameters are applied. These factors include, ultrasounds, microwaves,...
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Application of deep eutectic solvents in atomic absorption spectrometry
PublikacjaAtomic absorption spectrometry (AAS) is a widely applied technique for metal quantification due to its practicality, easy use and low cost. However, to improve the metrological characteristics of AAS, in particular the sensitivity and the detection limit, sample pretreatment is commonly used before the detection step itself. In consideration of the principles of Green Analytical Chemistry, new solvents are being introduced into...
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The Green Approach to the Synthesis of Bio-Based Thermoplastic Polyurethane Elastomers with Partially Bio-Based Hard Blocks
PublikacjaBio-based polymeric materials and green routes for their preparation are current issues of many research works. In this work, we used the diisocyanate mixture based on partially bio-based diisocyanate origin and typical petrochemical diisocyanate for the preparation of novel bio-based thermoplastic polyurethane elastomers (bio-TPUs). We studied the influence of the diisocyanate mixture composition on the chemical structure, thermal,...
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Development of chromatographic and mass spectrometry conditions for untargeted lipidomic analysis of human breast milk
PublikacjaHuman breast milk (HBM) is a complex biofluid containing components which are essential for the proper growth of the newborn (for example nutrients such as carbohydrates, proteins, lipids) and also bioactive substances. According to the literature, most of studies involving HBM nutrients investigations focused essentially on the determination of proteins. The molecular composition of lipids in HBM is not well known as the protein...
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Analysis of chiral pharmaceutical residues in influent and effluent samples at racemic and enantiomeric level using liquid chromatography-tandem mass spectrometry
PublikacjaIn this work, two different chromatographic methods for seasonal monitoring of pharmaceutical residue in wastewater samples were developed. In the case of enantiomeric separation of selected compounds, LC-MS technique combining with vancomycin based chiral stationary phase was used. The performance of chiral analysis enabled to monitor the pharmaceutical contamination at the enantiomeric level. The d-SPE procedure was developed...