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Search results for: MATRIX ASSISTED LASER DESORPTION IONIZATION–MASS SPECTROMETRY
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High-Throughput Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry as an Alternative Approach to Monitoring Drug Resistance of Hepatitis B Virus
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Boron-doped carbon nanowalls for fast and direct detection of cytochrome C and ricin by matrix-free laser desorption/ionization mass spectrometry
PublicationDetecting proteins via surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) method is still highly challenging, and only few examples of nanomaterials have been demonstrated to perform such detection so far. In this study, carbon nanowalls (CNWs), vertically aligned graphene sheet-based materials, presenting specific morphology, dimensions, and boron doping levels have shown improved performances for both qualitative...
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Carbon nanowalls: A new versatile graphene based interface for laser desorption/ionization-mass spectrometry detection of small compounds in real samples.
PublicationCarbon nanowalls, vertically aligned graphene nanosheets, attract attention owing to their tunable band-gap, high conductivity, high mechanical robustness, high optical absorbance and other remarkable properties. In this paper, we report for the first time, the use of hydrophobic boron-doped carbon nanowalls (CNWs) for laser desorption/ionization of small compounds and their subsequent detection by mass spectrometry (LDI-MS). The...
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Synthesis and characterization of novel renewable polyesters based on 2,5-furandicarboxylic acid and 2,3-butanediol
PublicationNovel polyesters from 2,5-furandicarboxylic acid or 2,5-dimethyl-furandicarboxylate and 2,3-butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n-butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser ionization-desorption...
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Synthetic Principles Determining Local Organization of Copolyesters Prepared from Lactones and Macrolactones
PublicationA highly effective and facile technique for catalytic ring-opening copolymerization (cROP) of lactones viz. ε- caprolactone and ε-decalactone with ω-pentadecalactone is being described. The reactions were mediated by Zn- and Cabased tridentate Schiff base complexes and benzyl alcohol as initiator. The catalysts were successfully employed for the preparation of numerous block and random copolymers. To unravel the composition of...
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Preparation of Allyl Alcohol Oligomers Using Dipicolinate Oxovanadium(IV) Coordination Compound
PublicationCurrently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H2O)2] 2 H2O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization–time-of-flight...
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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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The role of hydrogen bonding on tuning hard-soft segments in bio-based thermoplastic poly(ether-urethane)s
PublicationThis work describes the preparation of bio-based thermoplastic poly(ether-urethane)s (TPU) via a prepolymer method and investigates the effect of varying the interphase hydrogen-bonding (H-bonding) on physicochemical, thermal and mechanical properties. This was achieved by varying the glycol type and molar ratio of [NCO]/[OH] groups used during the prepolymer chain extending step. The TPUs’ chemical structure was analyzed by Fourier...
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Rubrene Thin Films with Viably Enhanced Charge Transport Fabricated by Cryo-Matrix-Assisted Laser Evaporation
PublicationAmong organic semiconductors, rubrene (RB; C42H28) is of rapidly growing interest for the development of organic and hybrid electronics due to exceptionally long spin diffusion length and carrier mobility up to 20 cm2V−1s−1 in single crystals. However, the fabrication of RB thin films resembling properties of the bulk remains challenging, mainly because of the RB molecule’s twisted conformation. This hinders the formation of orthorhombic...
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Organic semiconductor rubrene thin films deposited by pulsed laser evaporation of solidified solutions
PublicationOrganic semiconductor rubrene (C42H28) belongs to most preferred spintronic materials because of the high charge carrier mobility up to 40 cm2(V·s)-1. However, the fabrication of a defect-free, polycrystalline rubrene for spintronic applications represents a difficult task. We report preparation and properties of rubrene thin films deposited by pulsed laser evaporation of solidified solutions. Samples of rubrene dissolved in aromatic...
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Nanocrystalline Polymer Impregnated [Fe(pz)Pt(CN)4] Thin Films Prepared by Matrix-Assisted Pulsed Laser Evaporation
PublicationIn this work, the fabrication of [Fe(pz)Pt(CN)4] (pz = pyrazine) thin films by means of matrix-assisted pulsed laser evaporation (MAPLE) was investigated. As starting material, a cryogenically cooled suspension of anocrystalline [Fe(pz)Pt- (CN)4] (0.35wt.-%) in a mixture of 1,1-dichloroethane and polyethylene glycol (PEG) was used. Films of a thickness up to 150–200 nm were deposited on Si substrates by laser ablation at λ = 1064...
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The Mechanism of a Retro-Diels–Alder Fragmentation of Luteolin: Theoretical Studies Supported by Electrospray Ionization Tandem Mass Spectrometry Results
PublicationThe mechanisms of retro-Diels–Alder fragmentation of luteolin are studied theoretically using the Density Functional Theory method (B3LYP hybrid functional) together with the 6-311++G(d,p) basis set and supported by electrospray ionization tandem mass spectrometry (ESI-MS) results. The reaction paths leading to the formation of 1,3A and 1,3B fragment ions observed as the main spectral features in the ESI-MS spectrum are described...
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Direct Analysis of Samples of Various Origin and Composition Using Specific Types of Mass Spectrometry
PublicationOne of the major sources of error that occur during chemical analysis utilizing the more conventional and established analytical techniques is the possibility of losing part of the analytes during the sample preparation stage. Unfortunately, this sample preparation stage is required to improve analytical sensitivity and precision. Direct techniques have helped to shorten or even bypass the sample preparation stage; and in this...
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Application of safirinium N-hydroxysuccinimide esters to derivatization of peptides for high-resolution mass spectrometry, tandem mass spectrometry, and fluorescent labeling of bacterial cells
PublicationMass spectrometry methods are commonly used in the identification of peptides and biomarkers. Due to a relatively low abundance of proteins in biological samples, there is a need for the development of novel derivatization methods that would improve MS detection limits. Hence, novel fluorescent N-hydroxysuccinimide esters of dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium carboxylates (Safirinium P dyes) have been synthesized. The...
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Mass Spectrometry-Based Direct Analytical Techniques
PublicationDirect analysis of samples is considered as one of the most environmentally sustainable solutions in analytical chemistry. In the ideal case, such solutions do not require sample preparation and analytes separation steps, therefore do not consumpt harmful substances (or consumpt only minimum amounts of them) and do not generate hazardous waste. Technical solutions for direct analysis also offer miniaturized and field-portable analyzers...
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A framework for risk matrix design: A case of MASS navigation risk
PublicationRisk matrix, a tool for visualizing risk assessment results, is essential to facilitate the risk communication and risk management in risk-based decision-making processes related to new and unexplored socio-technical systems. The use of an appropriate risk matrix is discussed in the literature, but it is overlooked for emerging technologies such as Maritime Autonomous Surface Ships (MASS). In this study, a comprehensive framework...
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Advances in mass spectrometry for iron speciation in plants
PublicationIron is an important nutrient essential for plants and critical for human health. The state-of-the art of methods for iron speciation in cereal grains and plant fluids is critically reviewed. Particular attention is given to the latest developments in the coupling of HPLC with the parallel ICP MS and electrospray ionization (ESI) MS/MS detection, usually QTOF MS or Q-Orbitrap MS, for the identification and quantification of iron...
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Evaluation of Terpene Decomposition in Kaffir Lime Juice during Storage Using Gas Chromatography–Mass Spectrometry and Proton Transfer Reaction–Mass Spectrometry
PublicationKaffir lime juice, often treated as production waste, can be a good source of terpenes. These compounds undergo various decomposition processes under the influence of external factors, especially during transportation and storage. In this paper, it was possible to monitor changes in the terpene profile of kaffir lime juice under different storage conditions, namely, 4 ◦C, 20 ◦C, and 35 ◦C. The identification of key decomposition...
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Proton Transfer Reaction Mass Spectrometry for Plant Metabolomics
PublicationVolatile organic compounds (VOCs) emitted by plants are a valuable source of information on their growth, theirresponse to stress, and the condition of their habitat. The recent trend in the analysis of low-mass molecules ofplant origin is metabolomics, which in the context of volatiles is often referred to as volatolomics. It requires theuse of modern analytical instrumentation...
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Rapid ion-exchange matrix removal for a decrease of detection limits in the analysis of salt-rich reservoir waters for fluorobenzoic acids by liquid chromatography coupled with tandem mass spectrometry
PublicationA matrix removal procedure with ion-exchange resin prior to analysis for 18 fluorinated benzoic acids (FBAs) tracers in saline (>25% salt) reservoir water was optimized. The elimination of >98% of salt and the simultaneous matrix sample cleanup allowed the direct analysis using the supernatant by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This resulted in a gain in detection limits for most of the tracers...
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Two-Dimensional Gas Chromatography Coupled With Mass Spectrometry in Food Analysis
PublicationThe development of instrumental analytical techniques provided the opportunity for in-depth characterization of many food matrices. In particular, the use of gas chromatography coupled with mass spectrometry gives impressive results in terms of quality and authenticity testing, conducting food freshness evaluations and contamination assessments. A new variant of gas chromatography, namely two-dimensional gas chromatography (GC...
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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An optimal form of the finite element mass matrix in the analysis of longitudinal vibrations of rods
PublicationIn this paper, an attempt is made to find the optimal form of the mass matrix of a rod finite element, which allows one to obtain the smallest errors in the longitudinal frequency determination of natural vibrations of any boundary conditions within the whole range of determined frequencies. It is assumed that the mass matrix can be treated as a linear combination of the consistent and diagonal matrices. Based on analytical considerations,...
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Formation of surface layer in metal matrix composite A359/20SiCP during laser assisted turning
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Comprehensive two-dimensional gas chromatography-mass spectrometry: Recent evolution and current trends
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Main strategies, analytical trends and challenges in LC-MS and ambient mass spectrometry-based metabolomics
PublicationA plethora of analytical LC-MS-based methods have been successfully applied to analyses of complex samples of various origin for metabolomics investigations. Over the last ten years, the substantial evolution of ambient mass spectrometry (AMS) techniques has highlighted their tremendous potential in metabolomic studies due to the minimal sample pretreatment requirement and the ability to analyse samples in their native state. This...
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Calibration of the thermal desorption-gas chromatography-mass spectrometry system using standards generated in the process of thermal decomposition of chemically modified silica gel
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The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublicationIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
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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
PublicationThe 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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Determination of Metals Content in Wine Samples by Inductively Coupled Plasma-Mass Spectrometry
PublicationKnowledge about the metal content of wine is very important, for many reasons. Depending on the element, its quantity varies in wine from ng/L to mg/L. Despite the fact that metals are not directly connected to the taste and aroma of the wine, their content should be determined and controlled, because excess is undesirable, and in some cases prohibited, due to potential toxicity. Several analytical procedures for metal determination...
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Determination of Butyltin Species in Sea Water Samples Using Solid Phase Extraction Followed by Liquid Chromatography - Tandem Mass Spectrometry
PublicationReverse phase liquid chromatography (RP-HPLC)-electrospray ionization-tandem mass spectrometry (ESI-MS-MS) was evaluated for the analysis of TBT using solid phase extraction as sample preparation method. TBT was extracted from acidified water samples (spiked with tripropyltin as internal standard) using reversed phase polymeric Strata-X cartridges. Analytes were eluted from cartridges using acetonitrile-water mixture and the volume...
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Direct solid phase microextraction combined with gas chromatography – Mass spectrometry for the determination of biogenic amines in wine
PublicationA direct method based on immersion solid phase microextraction (DI-SPME) gas chromatography mass-spectrometry (GC-MS) was optimized and validated for the determination of 16 biogenic amines in Polish wines. In the analysis two internal standards were used: 1,7-diaminoheptane and bis-3-aminopropylamine. The method allows for simultaneous extraction and derivatization, providing a simple and fast mode of extraction and enrichment....
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Functional phase bistability in a nanocrystalline RbMn[Fe(CN)6] thin film fabricated by matrix-assisted laser evaporation
PublicationOne of the main barriers hindering applications of Prussian blue metal assemblies is their poor processability, which makes the fabrication of intact thin films very difficult. In this work, a nanocrystalline RbMn[Fe(CN)6]·xH2O film on silicon substrate was obtained for the first time via laser-stimulated deposition and investigated. Temperature-induced phase transition and bistability within broad hysteresis loop (120 K), along...
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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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Determination of antifreeze substances in the airport runoff waters by solid-phase microextraction and gas chromatography–mass spectrometry method
PublicationA new method has been developed for the determination of antifreeze agents such as ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) in the samples of airport runoff water. The method is based on headspace solid–phase microextraction (HS–SPME) of target analytes, which is coupled with gas chromatography–mass spectrometry (GC–MS). Until now, there was a lack of appropriate methodology for collecting reliable...
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An evaluation of sucrose as a possible contaminant in e-liquids for electronic cigarettes by hydrophilic interaction liquid chromatography–tandem mass spectrometry
PublicationThe influence of sucrose combustion products on smoking and nicotine addiction is still controversial because the presence of the sucrose may be treated as a source of aldehydes and organic acids. In e-liquids used as refills for electronic cigarettes, which are made primarily of poly(propylene glycol), glycerine and ethanol, sucrose may be present at trace levels, and its impact on mainstream smoke formation, and hence on human...
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Development of chromatographic and mass spectrometry conditions for untargeted lipidomic analysis of human breast milk
PublicationHuman 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 multi-class pharmaceuticals in fish tissues by ultra-high-performance liquid chromatography tandem mass spectrometry
PublicationA new sensitive method based on pressurized liquid extraction (PLE) and purification by gel permeation chromatography (GPC) prior to ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS) was developed for the determination in fish homogenate, liver and muscle of twenty pharmaceuticals compounds and metabolites from seven commonly used therapeutic families. An extensive matrix effect evaluation...
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Determination of hormones in water samples using liquid chromatography coupled with tandem mass spectrometry
PublicationOver the past few years, many synthetic (ethinylestradiol) and natural (estradiol,estriol, estrone) compounds present in the environment have been affecting the hormonalbalance of humans and animals. Steroid hormones are very often used for medical purposesand have high estrogenic activity what makes them endocrine disrupters. Most hormonalcompounds are released into the water as a result of their incomplete removal in wastewatertreatment...
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Evaluation of flavour profiles in e-cigarette refill solutions using gas chromatography–tandem mass spectrometry
PublicationMany flavour compounds that are present in e-liquids for e-cigarettes are responsible for specific tastes and smoking sensations for users. Data concerning content and specific types of flavours is often limited and unknown to users. The aim of the research was to define and compare flavour profiles of e-liquids with the same group taste from different manufacturers. Gas chromatography coupled with tandem mass spectrometry (GC–MS/MS)...
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The use of fast molecular descriptors and artificial neural networks approach in organochlorine compounds electron ionization mass spectra classification
PublicationDeveloping of theoretical tools can be very helpful for supporting new pollutant detection. Nowadays, a combination of mass spectrometry and chromatographic techniques are the most basic environmental monitoring methods. In this paper, two organochlorine compound mass spectra classification systems were proposed. The classification models were developed within the framework of artificial neural networks (ANNs) and fast 1D and...
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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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Comprehensive determination of flavouring additives and nicotine in e-cigarette refill solutions. Part I: Liquid chromatography-tandem mass spectrometry analysis
PublicationLiquid chromatography-tandem mass spectrometry with electrospray ionization (HPLC-ESI–MS/MS) methods were developed for the simultaneous determination of 42 flavouring compounds and nicotine in liquids for e-cigarettes. The chromatographic separation was performed using an Ace® Ultracore™ SuperC18™ (100 × 2.1 mm, 2.5 μm) column in both acidic and alkaline pH conditions to separate all the compounds. A simple “dilute & shoot” approach...
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Real-Time Monnitoring of Vegetable Oils' Thermal Degradation Using Proton Transfer Reaction Mass Spectrometry
PublicationThe volatile aldehydes, which are generated during frying, can be harmful to human health, therefore the concentration of these compounds in frying fumes should be monitored. In addition, aldehydes are markers of oils’ quality, and so it is possible to determine shelf-life or suitability for frying of these oils. Commonly, in order to determine aldehydes concentration gas chromatography is performed, however it does not allow for...
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Solid phase microextraction–comprehensive twodimensional gas chromatography–time-of-flight mass spectrometry: a new tool for determining PAHs in airport runoff water samples
Publicationfundamental aspect of airport operations is the pollution caused by airport runoff waters. Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups of xenobiotics which are commonly found in runoff water originating from airports. Only very limited data on the analysis of airport runoff water have been published until now. Therefore, a reliable and accurate analytical method based on headspace solid-phase microextraction...
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Phase I and phase II metabolism simulation of antitumor-active 2-hydroxyacridinone with electrochemistry coupled on-line with mass spectrometry.
PublicationHere, we report the metabolic profile and the results of associated metabolic studies of 2-hydroxyacridinone (2-OH-AC), the reference compound for antitumor-active imidazo- and triazoloacridinones. Electrochemistry coupled with mass spectrometry was applied to simulate the general oxidative metabolism of 2-OH-AC for the first time. The reactivity of 2-OH-AC products to biomolecules was also examined. The usefulness of the electrochemistry...
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Identification and characterization of the Indian Yellow dyestuff and its degradation products in historical oil paint tube by liquid chromatography mass spectrometry
PublicationAn analytical protocol for identification of dyes using reversed phase liquid chromatography-mass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/MS) is presented. The developed method has been successfully applied in identification of euxanthic acid and euxanthone, the main components of the Indian Yellow dye in a historical oil paint tube produced by Richard Ain`es, a recognizable French company supplying...
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Thermal decomposition of surface compounds for the generation of small quantities of acetaldehyde. Calibration of a thermal desorption gas chromatography flame ionization detection.
PublicationW pracy opisano sposób wytwarzania niewielkich ilości acetaldehydu w procesie termicznego rozkładu związku powierzchniowego uzyskanego w wyniku chemicznej modyfikacji żelu krzemionkowego.Proces rozkładu prowadzony jest w temperaturze 130-190 stopni Celsjusza.Przedstawiono również sposób syntezy prowadzący do uzyskania odpowiedniego związku powierzchniowego.
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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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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)...