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Search results for: chromatography
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Sample preparation for gas chromatographic determination of halogenated volatile organic compounds in environmental and biological samples
PublicationPodstawowym elementem przygotowania próbek środowiskowych i biologicznych do analizy jest etap izolacji i/lub wzbogacania polegający na przeniesieniu analitów z matrycy pierwotnej charakteryzującej się złożonym i często zmiennym składem (próbka oryginalna) do matrycy wtórnej z równoczesnym usunięciem substancji przeszkadzających (izolacja)i zwiększeniem stężenia analitów do poziomu powyżej granicy oznaczalności stosowanego przyrządu...
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Evaluation of headspace solid-phase microextraction for the analysis of volatile carbonyl compounds in spirits and alcoholic beverages
PublicationOpracowano metodę oznaczania C1-C6 związków karbonylowych w układzie GC-ECD w roztworach alkoholowych poprzez derywatyzację pentafluorobenzylohydroksy-aminą i mikroekstrakcję w fazie stacjonarnej z fazy nadpowierzchniowej. Zoptymalizowano warunki eksperymantalne: zawartość alkoholu, czas ekspozycji, temperaturę i sposób mieszania próbki. W metodzie tej najpierw przeprowadza się rozcieńczenie spirytusu lub napojów alkoholowych do...
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Solid phase extraction clean up of soil and sediment extracts for the determination of various types of pollutants in a single run.
PublicationOpisano nową procedurę oczyszczania ekstraktów rozpuszczalnikowych (uzyskanych w trakcie obróbki próbek gleby i osadów dennych) z wykorzystaniem techniki ekstrakcji do fazy stałej. Oryginalność podejścia polega na znalezieniu takiej kombinacji sorbentów, że uzyskuje się ekstrakt przygotowany do analizy chromatograficznej na zawartość różnych typów zanieczyszczeń (polichlorowane bifenyle, wielopierścieniowe węglowodory aromatyczne,...
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Multicriteria decision analysis in ranking of analytical procedures for aldrin determination in water
PublicationThe study presents the possibility of multi-criteria decision analysis (MCDA) application when choosing analytical procedures with low environmental impact. A type of MCDA, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), was chosen as versatile tool that meets all the analytical chemists – decision makers requirements. Twenty five analytical procedures for aldrin determination in water samples (as...
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New procedure of silica gel surface modification. Preparation of gaseousstandard mixtures for calibration purposes.
PublicationPrzedstawiono nową procedurę modyfikacji powierzchni żelu krzemionkowego z wykorzystaniem trimetyloaminy jako odczynnika. Próbki chemiczne modyfikowanego nośnika zostały wykorzystane do sporządzenia gazowych mieszanin wzorcowych (chlorek metylu jako składnik mierzony) techniką termicznego rozkładu związków powierzchniowych. Głównym celem badań było sprawdzenia przydatności nowej procedury modyfikacji powierzchni żelu do...
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Implementation of multicriteria decision analysis in design of experiment for dispersive liquid-liquid microextraction optimization for chlorophenols determination
PublicationA novel and efficient approach to optimization of extraction step prior the chromatographic determination of nine chlorinated phenols is described. It is based on the combination of design of experiments and multicriteria decision analysis. Such an approach is used to optimize dispersive liquid-liquid microextraction procedure for the determination of 9 chlorophenols in water samples. Three parameters are optimized – sample volume,...
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Sample preparation procedure using extraction and derivatization of carboxylic acids from aqueous samples by means of deep eutectic solvents for gas chromatographic-mass spectrometric analysis
PublicationThe paper presents a new procedure for the determination of organic acids in a complex aqueous matrixusing ultrasound-assisted dispersive liquid–liquid microextraction followed by injection port derivati-zation and GC–MS analysis. A deep eutectic solvent (choline chloride: 4-methylphenol in a 1:2 mol ratio)was used both as an extracting solvent and as a derivatizing agent to yield ion pairs which were next con-verted to methyl...
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Determination of polybrominated diphenyl ethers (PBDEs) in dust samples collected in air conditioning filters of different usage – method development
PublicationThis study presents the results of studies aimed at the development of an analytical procedure for separation, identification, and determination of PBDEs compounds in dust samples collected from automotive cabin air filters and samples collected from filters installed as part of the air purification system in academic facilities. Ultrasound-assisted dispersive solid phase extraction (UA-dSPE) was found to perform better in terms...
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Chromatographic lipophilicity determination using large volume injections of the solvents non-miscible with the mobile phase
PublicationA new perspective in the lipophilicity evaluation through RP-HPLC is permitted by analysis of the retentionfactor (k) obtained by injecting large volumes of test samples prepared in solvents immiscible withmobile phase. The experiment is carried out on representative groups of compounds with increasedtoxicity (mycotoxins and alkaloids) and amines with important biological activity (naturally occurringmonoamine compounds and related...
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Application of multicriteria decision analysis in solvent type optimization for chlorophenols determination with a dispersive liquid–liquid microextraction
PublicationThis study presents a novel support tool for the optimization and development of analytical methods. The tool is based on multi-criteria decision analysis (MCDA), namely the Technique for Order of Preference by Similarity to the Ideal Solution (TOPSIS), that allows users to rank possible solutions according to their requirements. In this study, we performed rankings of pairs of eight extraction and three dispersive solvents used...
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Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublicationOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
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Recent developments and future trends in solid phase microextraction techniques towards green analytical chemistry
PublicationSolid phase microextraction find increasing applications in the sample preparation step before chromatographic determination of analytes in samples with a complex composition. These techniques allow for integrating several operations, such as sample collection, extraction, analyte enrichment above the detection limit of a given measuring instrument and the isolation of analytes from sample matrix. In this work the information about...
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Determination of the amount of wash amines and ammonium ion in desulfurization products of process gases and results of related studies
PublicationPrzedstawiono metodę oznaczania tzw. amin myjących i ich produktów degradacji, włączając jon amonowy w wodach procesowych i ściekach wytwarzanych podczas odsiarczania gazów. W procesach rafinacji ropy naftowej zastosowano jonowymienną chromatografię cieczową z detektorem refraktometrycznym oraz tanią kationowymienną kolumnę HPLC. Otrzymane wyniki oznaczeń porównano z wynikami uzyskanymi przez miareczkowanie potencjometryczne....
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Miniaturised analytical procedure of determining polycyclic aromatic hydrocarbons and polychlorinated biphenyls in bottom sediments
PublicationOpisano metodę oznaczania bardzo niskich stężeń polichlorowanych bifenyli w obecności wysokich zawartości wielopierścieniowych węglowodorów aromatycznych. Analizie techniką GC-MS poddawany jest ekstrakt z 1 g próbki osadu. Jako standardy wewnętrzne zastosowano Naftalen-d8, benzo[a]antracen-d12 i PCB 209. Średni odzysk standardów przedstawiał się następująco: 65, 55 i 60% odpowiednio. Do izolacji frakcji PCB stosowano niekomercyjne...
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Using different types of capillary columns as denudation traps: a comparision of sorption properties
PublicationOpisano badania odcinków kapilarnych kolumn chromatograficznych (WCOT, SCOT,PLOT) jako pułapek denudacyjnych do ilościowego zatrzymywania śladowych ilości lotnych związków organicznych ze strumienia powietrza. W trakcie badań modelowych (z wykorzystaniem gazowych mieszanin wzorcowych) określono wartości współczynników podziału benzenu, toluenu, etylobenzenu, o-ksylenu i chlorobenzenu (Kfs). Stwierdzono, że grubość filmu fazy stacjonarnej...
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CE-UV method for the determination of catecholamine metabolites from baby pee-covered diapers
PublicationA method has been developed for the analysis of vanillylmandelic acid, homovanillic acid, and 5-hydroxyindoleacetic acid from baby urine as biomarkers of neuroblastoma in infants. Disposable diapers were employed as sampling devices in order to guarantee a low invasiveness during this step. The proposed method consists on a simple extraction step with water from the used diaper followed by the measurement using capillary electrophoresis...
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Determination of thiocyanate as a biomarker of tobacco smoke constituents in selected biological materials of human origin
Publicationn order to protect human health, it is necessary to biomonitor toxic substances originating from tobacco smoke in biological materials sampled from persons with different exposures to tobacco smoke constituents. Thiocyanate anion is a biomarker of exposure to tobacco smoke components which is characterized by a relatively long half‐life in the human body, i.e. 6 days. In this work, we present the results of thiocyanate determinations...
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Human bone marrow as a tissue in post-mortem identification and determination of psychoactive Substances—Screening methodology
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Multiplatform metabolomics provides insight into the molecular basis of chronic kidney disease
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Sample preparation procedures utilized in microbial metabolomics: An overview
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Ultra-high performance liquid chromatographic determination of levofloxacin in human plasma and prostate tissue with use of experimental design optimization procedures
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Development and validation of GC–MS/MS method useful in diagnosing intestinal dysbiosis
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Influence of the extraction mode on the yield of some furanocoumarins from Pastinaca sativa fruits
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Chemometric approach to correlations between retention parameters of non-polar HPLC columns and physicochemical characteristics for ampholytic substances of biological and pharmaceutical relevance
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Environmental Fate of Two Psychiatric Drugs, Diazepam and Sertraline: Phototransformation and Investigation of their Photoproducts in Natural Waters
PublicationExperimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry...
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Extraction Methods of 10-Deacetylbaccatin III, Paclitaxel, and Cephalomannine from Taxus baccata L. Twigs: A Comparison
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Application of Sea Sand Disruption Method for HPLC Determination of Quercetin in Plants
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Optimization of ASE Conditions for the HPLC Determination of Rutin and Isoquercitrin inSambucus nigraL
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Retention modeling of some saccharides separated on an amino column.
PublicationUsing an amino column (Supelcosil LC-NH2) and different mixtures of acetonitrile-water, quantitative structure-retention relationship models are discussed. These models are based on computed molecular descriptors representing numerically structured features of some saccharides. The obtained results are underlining the lipophilicity/hydrophilicity balance, and how this is controlling the separation of the saccharides. The resulting...
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Study of the chromatographic behavior of selected steroid hormones on aluminum oxide plates based on quantitative structure-retention relationships
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Chemical fingerprint ofPotentillaspecies by using HPTLC method
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Identification of novel psychoactive substances 25B-NBOMe and 4-CMC in biological material using HPLC-Q-TOF-MS and their quantification in blood using UPLC–MS/MS in case of severe intoxications
PublicationThis paper describes cases of poisoning caused by new psychoactive substances such as: 25BNBOMe (2-(4-bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine) and 4-CMC (1-(4-chlorophenyl)-2-(methylamino)-1-propanone). The analytical procedure includes rapid and selective method for the extraction and determination of 4-CMC and 25B-NBOMe in blood samples using UPLC–MS/MS technique. To the best of our knowledge,this is...
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Separation and determination of the group-type composition of modern base and lubricating oils with a wide range of polarity, especially emitted to the environment
PublicationLubricating oils are composed of base oils (>85% v/v) and enriching additives (<15% v/v). Three types of base oils may be distinguished: 1) traditional bases (obtained by low-volatile fractions from crude oil distillation refining), 2) synthetic bases (mainly poly-alpha-olefins, sometimes esters, especially succinic acid esters), 3) bases of natural origin (especially obtained from refined plant oils). The bases of natural origin...
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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
PublicationA new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an...
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Measurement of plasma 25-hydroxyvitamin D2, 25-hydroxyvitamin D3 and 3-epi-25-hydroxyvitamin D3 in population of patients with cardiovascular disease by UPLC-MS/MS method
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Effective phospholipid removal from plasma samples by solid phase extraction with the use of copper (II) modified silica gel cartridges
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A magnetic stir bar sorbent of metal organic frameworks, carbon foam decorated zinc oxide and cryogel to enrich and extract parabens and bisphenols from food samples
PublicationA porous composite magnetic stir bar adsorbent was fabricated for the extraction and enrichment of parabens and bisphenols from selected beverage samples. The adsorbent comprised a metal organic framework, carbon foam decorated zinc oxide and magnetic nanoparticles embedded in polyvinyl alcohol cryogel. The porous composite stir bar adsorbent could adsorb parabens and bisphenols via hydrogen bonding, π-π and hydrophobic interactions....
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Validated HPTLC method for determination of ledol and alloaromadendrene in the essential oil fractions of Rhododendron tomentosum plants and in vitro cultures and bioautography for their activity screening
PublicationRhododendron tomentosum (Ledum palustre) is a bog shrub used in traditional medicine for treatment of respiratory and rheumatic diseases. Due to the large variability of the chemical composition of its essential oil, depending on the habitat, the in vitro cultures were established as the alternative source of the volatile fraction. There is a need to monitor a quality of the field grown as well as in vitro plant material, especially...
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Niebezpieczeństwo ukryte w żywności-aminy biogenne. Cz. II. Metody oznaczania i wyzwania.
PublicationZe względu na aktywność biologiczną amin biogennych ich oznaczanie zarówno jakościowe, jak i ilościowe w żywności ma istotne znaczenie w celu zapewnienia ochrony zdrowia i życia ludzkiego. Obecnie do monitoringu amin biogennych w żywności najczęściej wykorzystuje się: wysokosprawną chromatografię cieczową (HPLC), chromatografię cienkowarstwową (TLC) oraz absorpcyjną spektrofotometrię cząsteczkową. Są to jednak techniki czasochłonne,...
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Analysis of arsenic species in environmental samples
PublicationMany analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas...
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Analytical methodologies for determination of artificial sweeteners in foodstuffs- a review
PublicationArtificial high-intensity sweeteners are more and more frequently used for food production. Food industry tends to highlight beneficial aspects of their use, such as tooth-friendliness, rising-up quality of life of those suffering from different forms of diabetes and possibility of weight control without sacrificing favorite unhealthy drinks or snacks. On the other hand some of the consumers are deeply concerned about safety of...
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Nowe substancje psychoaktywne Cz. III. Syntetyczne katynony-charakterystyka, metody oznaczania i wyzwania analitycznje
PublicationSyntetyczne katynony to druga co do liczebności (po syntetycznych kannabinoidach) grupa nowych substancji psychoaktywnych będących składnikiem dopalaczy zabezpieczanych przez policję w nielegalnym handlu. Substancje te po raz pierwszy wykryto w Europie w 2004 r., a do końca roku 2015 zidentyfikowano aż 103 nowe związki z tej grupy. Możliwość wprowadzania dodatkowych grup funkcyjnych w strukturę katynonu pozwala na niezwykle wiele...
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Techniki chromatografii w rozdzielaniu i oznaczaniu ekdysteroidów w Rhaponticum carthamoides
PublicationRhaponticum carthamoides to syberyjska endemiczna wieloletnia bylina, od wieków wykorzystywana w medycynie ludowej, jako preparat wzmacniający organizm. Główną grupą związków chemicznych, występujących w roślinie oraz wzbudzających szczególne zainteresowanie, ze względu na wykazywaną aktywność, są ekdysteroidy. Dlatego też poznanie ich dokładnego składu oraz stężeń w tkankach roślinnych staje się istotnym elementem poznawczym oraz...
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Common methods for the chiral determination of amphetamine and related compounds II: Capillary electrophoresis and nuclear magnetic resonance
PublicationAmphetamine group and related ring-substituted substances are generally synthetic compounds, belonging to one of the most heavily abused drug groups in recent years. Some compounds in this class also originate from plants. Analysis of the enantiomers of AM-type compounds and metabolites is extremely important for a number of scientific disciplines. From studies of biological activity or mechanisms through determination of precursor...
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The potential of LC–MS technique in direct analysis of perfume content
PublicationPerfumes are products that consist of a wide range of natural and synthetic compounds. Due to complex composition, the determination of their ingredients is a difficult task. Most of the perfume components are either volatile or semi-volatile; however, most of the attention has been paid to volatile ones, and thus, gas chromatography or electronic noses are generally used. Nevertheless, in this study, liquid chromatography coupled...
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Recent Applications of 1D GC-MS and 2D GC-MS in Foodomics Studies
PublicationGas chromatography coupled with mass spectrometry and food chemistry have been tightly linked since the 1960s. This setup is also an integral part of the omics studies when it comes to low mass metabolites. Therefore, the marriage of GC-MS and foodomics is obvious. Two-dimensional gas chromatography coupled with mass spectrometry fits perfectly within the latest trends in foodomics, since it is tailored for holistic food analysis....
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Post-Chromatographic Derivatization Coupled with Mass Spectrometry as a Method of Profiling and Identification of Antioxidants; Ligustrum vulgare Phytocomplex as an Example
PublicationHigh-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) coupled with radical scavenging assays, such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) can be both used for the detection of the antioxidants in plant extracts. In this study, the ethanolic (70% v/v) extracts from different morphological parts of Ligustrum vulgare collected...
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Sample preparation procedure for the determination of polycyclic aromatic hydrocarbons in petroleum vacuum residue and bitumen
PublicationThis paper describes a novel method of samplepreparation for the determination of trace concentrations ofpolycyclic aromatic hydrocarbons (PAHs) in high-boilingpetroleum products. Limits of quantitation of the investigatedPAHs in materials of this type range from tens ofnanograms per kilogram to <20 μg/kg. The studies revealedthat in order to separate most of interferences from theanalytes without a significant loss of PAHs, it...
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Turmeric nanofiber-encapsulated natural product formulation act as a phytogenic feed additive—A study in broilers on growth performance, biochemical indices of blood, and E. coli in cecum
PublicationA phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased...
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Characterization of home-made and regional fruit wines by evaluation of correlation between selected chemical parameters
PublicationSince 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...