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Modeling of chromatographic lipophilicity of food synthetic dyes estimated on different columns
PublikacjaBadano parametry retencyjne wybranych syntetycznych barwników żywności z wykorzystaniem techniki RP-HPLC z wykorzystaniem kolumn z chemicznie modyfikowanym wypełnieniem typu C-8, C-16, C-18 oraz CN.Uzyskane wyniki mogą być podstawą do stwierdzenia, że badane związki charakteryzują się podobnymi parametrami retencyjnymi w stosunku do kolumn z fazą stacjonarną typu C-8, C-16 oraz C-18.
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Group-type analysis of middle distillates by test method IP-391/EN-12916/ASTM D6379 in terms of resolution and selectivity of chromatographic columns
PublikacjaNa podstawie wyników badań z zastosowaniem różnych kolumn typu NH2 opisano wpływ selektywności wypełnienia kolumn HPLC na wyniki analizy grupowej węglowodorów aromatycznych oraz określono wymagania jakie powinna spełniać kolumna do oznaczania grup węglowodorów aromatycznych w średnich destylatach ropy naftowej. Badania przeprowadzono stosując metodykę analityczną według normy IP-391/EN-12916 albo ASTM D 6379.
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Transportable, Portable and Micro Gas Chromatographs
PublikacjaSignificant benefits can be obtained by miniaturization of conventional benchtop gas chromatographs. The attractive features arising from miniaturization include low-power requirements, low heat capacity of separation columns, low consumption of mobile phase, enhanced performance, higher portability, and easily coupling to detectors and secondary chromatographic systems. In separation sciences, including gas phase separations,...
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Characterization of 1,3-alternate calix[4]arene-silica bonded stationary phases and their comparison to selected commercial columns by using principal component analysis
PublikacjaTwelve calix[4]arene stationary phases in 1,3-alternate conformation, synthesized in the authors laboratory, were characterized in terms of their surface coverage, hydrophobic selectivity, aromatic selectivity, shape selectivity, hydrogen bonding capacity and ion-exchange capacity. The set of tests commonly used for evaluation of commercially available stationary phases was applied to assess fundamental chromatographic properties...
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Application of the chromatographic retention index system for the estimation of the calibration constants of permeation passive samplers with polydimethylsiloxane membranes
PublikacjaThe paper presents the results of research on the calibration of permeation passive samplers equipped with polydimethylsiloxane (PDMS) membranes using the physico-chemical properties of the analytes. Strong correlations were found between the calibration constants of the samplers and the linear temperature-programmed retention indices of the analytes determined on columns coated with pure PDMS (r2 = 0.914). These correlations...
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Polycyclic aromatic hydrocarbons as test probes to investigate the retention behavior of 1,3-alternate calix[4]arene silica-bonded stationary phases
PublikacjaA series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, fourring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated...
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Determination of SCFAs in water using GC-FID. Selection of the separation system
PublikacjaIn the present study, an analytical procedure was developed for the determination of short-chain fatty acids (SCFAs) in landfill leachate and municipal wastewater employing injection of aqueous samples to gas chromatograph with flame ionization detector (GC-FID). Chromatographic conditions such as a separation system, injection volume, oven temperature program were investigated and selected. With two columns, one with a polar (polyethylene...
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Quality evaluation of agricultural distillates using different types of electronic noses
PublikacjaThe paper presents the results of investigation on quality evaluation of agricultural distillates using a prototype of electronic nose instrument and a commercial electronic nose of Fast/Flash GC type – HERACLES II. The prototype was equipped with TGS type semiconductor sensors. HERACLES II included two chromatographic columns with different polarity of stationary phase and two FID detectors. In case of the prototype volatile fraction...
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Novel stationary phases based on asphaltenes for gas chromatography
PublikacjaWe present the results of investigations on the possibility of the application of the asphaltene fraction isolated from the oxidized residue from vacuum distillation of crude oil as a stationary phase for gas chromatography. The results of the investigation revealed that the asphaltene stationary phases can find use for the separation of a wide range of volatile organic compounds. The experimental values of Rohrschneider/McReynolds...
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Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC
PublikacjaReverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery...
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Current trends in analytical strategies for the determination of polybrominated diphenyl ethers (PBDEs) in samples with different matrix compositions – Part 2: New approaches to PBDEs determination
PublikacjaHerein, we review the latest technical solutions for polybrominated diphenyl ethers (PBDEs) determination in samples with different matrix compositions, largely focusing on gas chromatography but also presenting some liquid chromatography–based solutions. Moreover, we discuss the use of diverse sample injection techniques while considering the advantages and disadvantages of each injection system in the context of PBDEs analysis....
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Studies of the separation performance of silanized silica gel for simulated distillation
PublikacjaWe present the results of investigations of the chromatographic (sorptive) properties of silanized silica gel as a stationary phase for gas chromatography used for simulated distillation. Commercially available silanized sorbent (particle diameter range 63–200 m, average pore size 60 Å) was sieved to obtain the 80–100 mesh fraction (180–150 m). The obtained results revealed that silanized silica gel allows the complete separation...
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A natural deep eutectic solvent - protonated L-proline-xylitol - based stationary phase for gas chromatography
PublikacjaThe paper presents a new kind of stationary phase for gas chromatography based on deep eutectic solvents (DES) in the form of a mixture of L-proline (protonated with hydrochloric acid) as a hydrogen bond acceptor (HBA) and xylitol as a hydrogen bond donor (HBD) in a molar ratio of HBA:HBD 5:1. DES immobilized on a silanized chromatographic support was tested by gas chromatography (GC) in order to determine its resolving power for...
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Comparison of hydrophilic interaction and reversed phase liquid chromatography coupled with tandem mass spectrometry for the determination of eight artificial sweeteners and common steviol glycosides in popular beverages
PublikacjaHydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MS/MS) was used to separate artificial and natural sweeteners approved for use in European Union (EU). Among three tested HILIC columns (BlueOrchid PAL-HILIC, Ascentis Express Si and Acclaim™ Trinity™ P2) the last one was selected for the development of HILIC method due to the best results obtained with it. Early eluting and coeluting compounds...
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublikacjaThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences
PublikacjaNanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...