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Philip J. Marriott - One of the best experts on this subject based on the ideXlab platform.
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Comprehensive Two-Dimensional Gas Chromatography with Mass Spectrometry: Toward a Super-Resolved Separation Technique.
Analytical chemistry, 2020Co-Authors: Yada Nolvachai, Laura Mcgregor, Natasha D. Spadafora, Nicholas P. Bukowski, Philip J. MarriottAbstract:A data interpretation and processing approach for improved compound identification and data presentation in comprehensive Two-Dimensional Gas Chromatography (GCxGC) is described. A footprint peak o...
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Multi-column trajectory to advanced methods in comprehensive Two-Dimensional Gas Chromatography
TrAC Trends in Analytical Chemistry, 2018Co-Authors: Yada Nolvachai, Chadin Kulsing, K.m. Sharif, Yong Foo Wong, Sung-tong Chin, Blagoj Mitrevski, Philip J. MarriottAbstract:Abstract Comprehensive Two-Dimensional Gas Chromatography (GC×GC) and multidimensional GC (MDGC) offer high performance separation capability towards multi-component samples, and improved sample characterisation. Recent advances, particularly with new GC×GC methodologies, which apply additional columns to GC×GC, along with hyphenation with mass spectrometry, potentially have a tremendous impact on the analysis of various applications such as food, petrochemicals, fragrances, drugs and environmental samples. The present review highlights the new experimental designs in GC×GC coupled with MDGC to offer significant changes in operational performance, and applications of these technologies which have been developed since 2000.
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Interpretation of comprehensive Two-Dimensional Gas Chromatography data using advanced chemometrics
TrAC Trends in Analytical Chemistry, 2014Co-Authors: Zhongda Zeng, Helmut M. Hügel, Philip J. MarriottAbstract:Abstract The power of comprehensive Two-Dimensional Gas Chromatography (GC × GC) for the study of complex mixtures has been indisputably proved in the past several decades. This review encompasses the whole of GC × GC-related data processing and summarizes relevant applications. We include theoretical introduction to some specific methods and studies to aid readers’ understanding of chemometrics strategies for advanced data interpretation.
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Characterization of petrochemical samples and their derivatives by comprehensive Two-Dimensional Gas Chromatography
Química Nova, 2006Co-Authors: Carin Von Mühlen, Cláudia Alcaraz Zini, Elina Bastos Caramão, Philip J. MarriottAbstract:The goal of this article is to discuss the application of comprehensive Two-Dimensional Gas Chromatography (GCxGC) to petrochemical samples. The use of GCxGC for petroleum and petroleum derivatives characterization, through group type analysis, or BTEX (benzene, toluene, ethylbenzene, xylenes), total aromatic hydrocarbons, polyaromatic hydrocarbons, sulfur-containing, oxygen-containing, and nitrogen-containing compounds is presented. The capability of GCxGC to provide additional specific chemical information regarding petroleum processing steps, such as dehydrogenation of linear alkanes, the Fischer-Tropsch process, hydrogenation and oligomerization is also described. In addition, GCxGC analyses of petrochemical biomarkers and environmental pollutants derived from petrochemicals are reported.
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Orthogonality considerations in comprehensive Two-Dimensional Gas Chromatography.
Journal of Chromatography A, 2005Co-Authors: Danielle Ryan, Paul Morrison, Philip J. MarriottAbstract:This study explores separation orthogonality with respect to comprehensive Two-Dimensional Gas Chromatography (GC x GC) for a range of different column polarities in the first dimension (1D), with two second dimension (2D) column types. Systematic variation in the net polarity of the first dimension allows the effect of column phase relative polarity on analyte retention in both the first and second dimensions to be evaluated. First dimension polarity manipulation significantly affects elution temperature (T(e)) of the analytes. This alters the magnitude of retention on the second dimension, and the extent of utility of separation space. By use of retention factor/temperature data in single column experiments, along with 1D T(e) data, retention on the 2D column can be estimated. This allows the Two-Dimensional separation to be predicted, and compared with experimental data. Predicted GC x GC peak positions corresponded favourably with the experimentally derived chromatograms, yielding a simple approach for predicting Two-Dimensional separations, using unique column set combinations.
Tadeusz Górecki - One of the best experts on this subject based on the ideXlab platform.
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Comprehensive Two-Dimensional Gas Chromatography in environmental analysis
TrAC Trends in Analytical Chemistry, 2018Co-Authors: Alina M. Muscalu, Tadeusz GóreckiAbstract:Abstract Comprehensive Two-Dimensional Gas Chromatography (GC × GC) offers increased peak capacity and selectivity relative to conventional one dimensional separations. The analysis of persistent organic pollutants in environmental matrices is very challenging due to the large number of compounds with varying chemical and physical properties that are typically present in the sample at the same time at concentrations ranging from ultra-trace to percent levels. GC × GC is steadily gaining in popularity in environmental analysis and the number of publications citing the use of this technique has been increasing significantly in the recent years. An overview of the latest applications in the environmental field is presented in this paper, emphasizing the advances for targeted and non-targeted analysis in complex matrices. In addition, instrumentation, data interpretation approaches, as well as the quality assurance and control for routine analyzes are discussed.
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Optimization aspects of comprehensive Two-Dimensional Gas Chromatography.
Journal of chromatography. A, 2012Co-Authors: Ahmed Mostafa, Matthew Edwards, Tadeusz GóreckiAbstract:Abstract Comprehensive Two-Dimensional Gas Chromatography (GC × GC) was first introduced nearly two decades ago. Currently, it is one of the most powerful and effective techniques for the characterization and analysis of a variety of complex mixtures. GC × GC is based upon separations utilizing two chromatographic columns of differing selectivity, connected in series through an interface known as the modulator. The main role of the modulator is to trap and/or sample the primary column effluent and periodically inject it into the secondary column. This increasingly popular technique results in an enhanced separation with greatly improved peak capacity. In addition, structured chromatograms are typically generated when compounds belonging to homologous series are present in the sample. However, method optimization in GC × GC can be difficult and time-consuming. This review focuses on the optimization of main operational parameters in GC × GC. Consideration is given to aspects such as stationary phase chemistries, column dimensions, carrier Gas flow, temperature programs, modulation and detector settings.
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Comprehensive Two-Dimensional Gas Chromatography (GC×GC) in environmental analysis and monitoring
Analytical and bioanalytical chemistry, 2006Co-Authors: Ognjen Pani, Tadeusz GóreckiAbstract:Compared to conventional one-dimensional Gas Chromatography (1D-GC), comprehensive Two-Dimensional Gas Chromatography (GC×GC) offers increased peak capacity, improved resolution and enhanced mass sensitivity. In addition, it generates structured Two-Dimensional (2-D) chromatograms, which aids in the identification of compound classes. Sample preparation procedures can often be minimized, or even eliminated in some cases, due to the superior separating power offered by the technique. All of these advantages make GC×GC a very powerful tool in environmental analysis involving the determination of trace levels of toxic compounds in complex matrices. This review paper summarizes and examines the historical and recent GC×GC applications in environmental analysis and monitoring.
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Recent Advances in Comprehensive Two‐Dimensional Gas Chromatography (GC×GC)
Journal of Liquid Chromatography & Related Technologies, 2006Co-Authors: Tadeusz Górecki, Ognjen Panić, Nathan OldridgeAbstract:Abstract Fourteen years after its introduction, comprehensive two‐dimensional Gas Chromatography (GC×GC) is one of the most powerful analytical tools available for the analysis of very complex samples. The technique is based on the application of two GC columns coated with different stationary phases, connected in series through a special interface (modulator). The interface not only physically connects the two columns, but also ensures the preservation of the separation achieved in the first separation dimension. Compounds coeluting from the first column undergo additional separation in the second column. This leads to vastly increased separation power of the technique compared to conventional 1D GC. This paper reviews the development of the technique, focusing on the most recent advances in the GC×GC field. It describes the principles of the technique, the basics of data processing, instrumentation development, and selected applications.
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the evolution of comprehensive two dimensional Gas Chromatography gc x gc
IEEE Journal of Solid-state Circuits, 2004Co-Authors: Tadeusz Górecki, James J. Harynuk, Ognjen PanicAbstract:For a technology little over a decade old, comprehensive Two-Dimensional Gas Chromatography (GC x GC) has quickly reached the status of one of the most powerful analytical tools for volatile organic compounds. At the heart of any GC x GC system is an interface, which physically connects the primary and the secondary columns and acts to preserve the separation obtained in the first dimension (first column) while allowing additional separation in the second dimension. The paper presents a review of the technology, including fundamental principles of the technique, data processing and interpretation and a timeline of inventive contributions to interface design. In addition, applications of the technique are presented, with a more detailed discussion of selected examples.
Robert A. Shellie - One of the best experts on this subject based on the ideXlab platform.
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Uniformity and Sensitivity Improvements in Comprehensive Two-Dimensional Gas Chromatography Using Flame Ionization Detection with Post-Column Reaction
Analytical chemistry, 2019Co-Authors: Jim Luong, Yujuan Hua, Ronda Gras, Robert A. ShellieAbstract:A 3D-printed microreactor for post-column reactions was successfully integrated with comprehensive two -dimensional Gas Chromatography. A two-stage post-column reaction provided a carbon-independent response, enhanced the flame ionization detection uniformity, and improved the detector sensitivity. These enhancements are critical to overcome challenges in analyses using comprehensive Two-Dimensional Gas Chromatography and flame ionization detection, which aim to separate and quantify multiple components. Post-column reaction flame ionization detection eliminated the requirement of multilevel and multicompound calibration, it enabled the determination of target analytes with a single-carbon-containing calibration compound with an accuracy of ±10%, and it improved the sensitivity for compounds that were not efficiently ionized by flame ionization detection. Extra column band-broadening caused by the incorporation of the 3D-printed microreactor was minimized using optimized reactor operating parameters and ...
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Parallel comprehensive Two-Dimensional Gas Chromatography
Journal of chromatography. A, 2017Co-Authors: Dandan Yan, Laura Tedone, Anthony Koutoulis, Simon P. Whittock, Robert A. ShellieAbstract:We introduce an information rich analytical approach called parallel comprehensive Two-Dimensional Gas Chromatography (2GC × 2GC). This parallel Chromatography approach splits injected samples into two independent Two-Dimensional column ensembles and provides two GC × GC separations by using contra-directional thermal modulation. The first-dimension (1D) and second-dimension (2D) columns are connected using planar three-port microchannel devices, which are supplied with supplementary flow via two pressure controller modules. Precise carrier Gas flow control at the junction of the 1D and 2D columns permits independent control of flow conditions in each separation column. The 2GC × 2GC approach provides two entirely independent GC × GC separations for each injection. Analysis of hop (Humulus lupulus L.) essential oils is used to demonstrate the capability of the approach. The analytical performance of each GC × GC separation in the 2GC × 2GC experimentis comparable to individual GC × GC separation with matching column configurations. The peak capacity of 2GC × 2GC is about 2 times than that of single GC × GC system. The dual 2D chromatograms produced by this single detector system provide complementary separations and additional identification information by harnessing different selectivity provided by the four separation columns.
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Thermal Independent Modulator for Comprehensive Two-Dimensional Gas Chromatography
Analytical chemistry, 2016Co-Authors: Jim Luong, Ronda Gras, Xiaosheng Guan, Robert A. ShellieAbstract:We introduce a modulation strategy for comprehensive Two-Dimensional Gas Chromatography (GC×GC) with complete thermal independence between the cooling and heating stages and without the need for GC oven heat for remobilization. Based on this approach, a compact thermal independent modulator (TiM) with thermoelectric cooling and micathermic heating has been successfully innovated for use in GC×GC. The device operates externally to a Gas chromatograph, does not require liquid cryogen, and has minimal consumables requirements. The augmentation of an additional Gas flow stream results in a number of critical chromatographic parameter improvements such as the decoupling of flows of first- and second-dimension columns to attain both efficiency and speed optimized flow in each dimension, the potential for independent retention time locking or scaling in either dimension, the improvement of modulator reinjection efficiency, as well as facilitating back-flushing for the first dimension to enhance system cleanlines...
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Molecular interconversion behaviour in comprehensive Two-Dimensional Gas Chromatography.
Journal of chromatography. A, 2004Co-Authors: Philip J. Marriott, Robert A. Shellie, Danielle Ryan, Kornakanok Aryusuk, Kanit Krisnangkura, Volker Schurig, Oliver TrappAbstract:Comprehensive Two-Dimensional Gas Chromatography (GC x GC) is shown to provide information on dynamic molecular behaviour (interconversion), with the interconversion process occurring on both columns in the coupled-column experiment. The experiment requires suitable adjustment of both experimental conditions and relative dimensions of each of the columns. In this case, a longer column than normally employed in GC x GC allows sufficient retention duration on the second column, which permits the typical plateau-shape recognised for the interconversion process to be observed. The extent of interconversion depends on prevailing temperature, retention time, and the phase type. Polyethylene glycol-based phases were found to result in high interconversion kinetics, although terephthalic acid-terminated polyethylene glycol had a lesser extent of interconversion. Much less interconversion was seen for phenyl-methylpolysiloxane and cyclodextrin phases. This suggests that for the oximes, interconversion largely occurs in the stationary phase. Examples of different extents of interconversion in both dimensions are shown, including peak coalescence on the first column with little interconversion on the second column.
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Multidimensional and Comprehensive Two-Dimensional Gas Chromatography
Lc Gc Europe, 2003Co-Authors: Philip J. Marriott, Robert A. Shellie, Paul D. Morrison, Michael S. Dunn, Eka Sari, Danielle RyanAbstract:Coupled-column GC analysis has had a long and successful history. From methods as diverse as simple direct sequential connection of columns, through intermediate pressure-tuning and flow-modulated operation, to conventional and advanced heartcut multidimensional GC (MDGC), and most recently comprehensive Two-Dimensional Gas Chromatography (GC GC), it is clear that the search for innovative ways with which to exploit the ease of multi(dual)-column geometries for enhancing the separation power of GC has been an on-going goal. Here, we explore briefly the different modes that have been used in MDGC, highlighting the GC GC technique, and the ways that these have opened up various expanded capacity strategies for volatile and complex sample analysis. The long history of MDGC belies the very recent surge in activity surrounding GC GC, and we conclude that this offers the ultimate high-resolution opportunity for volatile and semi-volatile analysis. Within the technology specifically developed for GC GC, several new multidimensional approaches have been developed in parallel. These are also placed into context.
Fabio Augusto - One of the best experts on this subject based on the ideXlab platform.
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Characterization of crude oil biomarkers using comprehensive Two-Dimensional Gas Chromatography coupled to tandem mass spectrometry.
Journal of separation science, 2016Co-Authors: Noroska Gabriela Salazar Mogollón, Paloma Santana Prata, Jadson Zeni Dos Reis, Eugenio V. Santos Neto, Fabio AugustoAbstract:Oil samples from Reconcavo basin (NE Brazil), previously analyzed by traditional techniques such as Gas Chromatography coupled to tandem mass spectrometry, were evaluated using comprehensive Two-Dimensional Gas Chromatography coupled to quadrupole mass spectrometry and comprehensive Two-Dimensional Gas Chromatography coupled to tandem mass spectrometry along with simplified methods of samples preparation to evaluate the differences and advantages of these analytical techniques to better understand the development of the organic matter in this basin without altering the normal distribution of the compounds in the samples. As a result, the geochemical parameters calculated by comprehensive Two-Dimensional Gas Chromatography coupled to tandem mass spectrometry described better the origin, maturity, and biodegradation of both samples probably by increased selectivity, resolution, and sensitivity inherent of the multidimensional technique. Additionally, the detection of the compounds such as, the C(14α-) homo-26-nor-17α-hopane series, diamoretanes, nor-spergulanes, C19 -C26 A-nor-steranes and 4α-methylsteranes resolved and detected by comprehensive Two-Dimensional Gas Chromatography coupled to tandem mass spectrometry were key to classify and differentiate these lacustrine samples according to their maturity and deposition conditions.
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Solid‐phase microextraction combined with comprehensive two‐dimensional Gas Chromatography for fatty acid profiling of cell wall phospholipids
Journal of separation science, 2012Co-Authors: Stanislau Bogusz, Leandro W. Hantao, Soraia C.g.n. Braga, Valtenice De Cássia Rodrigues De Matos França, Marcelo Fernandes Da Costa, Russell D. Hamer, Dora Fix Ventura, Fabio AugustoAbstract:The combination of solid-phase microextraction (SPME) with comprehensive twodimensional Gas Chromatography is evaluated here for fatty acid (FA) profiling of the glycerophospholipid fraction from human buccal mucosal cells. A base-catalyzed derivatization reaction selective for polar lipids such as glycerophospholipid was adopted. SPME is compared to a miniaturized liquid‐liquid extraction procedure for the isolation of FA methyl esters produced in the derivatization step. The limits of detection and limits of quantitation were calculated for each sample preparation method. Because of its lower values of limits of detection and quantitation, SPME was adopted. The extracted analytes were separated, detected, and quantified by comprehensive Two-Dimensional Gas Chromatography with flame ionization detection (FID). The combination of SPME and comprehensive Two-Dimensional Gas Chromatography with FID, using a selective derivatization reaction in the preliminary steps, proved to be a simple and fast procedure for FA profiling, and was successfully applied to the analysis of adult human buccal mucosal cells.
Luigi Mondello - One of the best experts on this subject based on the ideXlab platform.
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Chapter 7:Comprehensive Two-Dimensional Gas Chromatography
Advanced Gas Chromatography in Food Analysis, 2019Co-Authors: Peter Quinto Tranchida, Luigi MondelloAbstract:This chapter contains information related to the use of comprehensive Two-Dimensional Gas Chromatography (GC×GC) for the analysis of compounds contained in food products. General principles, basic theory and practical issues, along with instrumental features, are reported. In particular, and apart from other forms of detection, the use of various forms of mass spectrometry (MS) is described in detail. A series of GC×GC food-related applications (untargeted, targeted and fingerprinting), using both MS and non-MS detectors, are critically discussed.
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comprehensive two dimensional Gas Chromatography mass spectrometry recent evolution and current trends
Mass Spectrometry Reviews, 2016Co-Authors: Peter Quinto Tranchida, Paola Dugo, Flavio A Franchina, Luigi MondelloAbstract:The present contribution is focused on the evolution and current trends of comprehensive Two-Dimensional Gas Chromatography-mass spectrometry (GC × GC-MS), with respect to a review that described this specific methodology published at the beginning of 2008 (Mondello et al., 2008). In fact, since then there has been considerable evolution in the MS field, certainly exceeding that observed in GC × GC. In particular, the present paper will cover the combination of novel MS machines [single quadrupole (Q) and triple quadrupole, isotope ratio, low- and high-resolution time-of-flight (ToF), hybrid (Q-ToF)] to GC × GC systems, and will position comprehensive Two-Dimensional Gas Chromatography within the wider context of separation science. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 35:524-534, 2016.
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the penetration of green sample preparation techniques in comprehensive two dimensional Gas Chromatography
Trends in Analytical Chemistry, 2015Co-Authors: Peter Quinto Tranchida, Paola Dugo, Giorgia Purcaro, Mariarosa Maimone, Luigi MondelloAbstract:Abstract This critical review focuses on the use and the penetration of green sample-preparation (GSP) methods in comprehensive Two-Dimensional Gas Chromatography (GC × GC). The first GSP GC × GC experiment (supercritical-fluid extraction) appeared in 1994, and, since then, there has been a relatively-moderate use of this combination. Specifically, one approach (solid-phase microextraction) has been exploited quite often, while all others very rarely, apart from solid-phase extraction, which often does not fully fit within the GSP category. As well as descriptions of significant GSP GC × GC applications, we explain this divergent tendency and describe possible future scenarios.
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Impact of comprehensive two‐dimensional Gas Chromatography with mass spectrometry on food analysis
Journal of separation science, 2015Co-Authors: Peter Quinto Tranchida, Giorgia Purcaro, Mariarosa Maimone, Luigi MondelloAbstract:Comprehensive Two-Dimensional Gas Chromatography with mass spectrometry has been on the separation-science scene for about 15 years. This three-dimensional method has made a great positive impact on various fields of research, and among these that related to food analysis is certainly at the forefront. The present critical review is based on the use of comprehensive Two-Dimensional Gas Chromatography with mass spectrometry in the untargeted (general qualitative profiling and fingerprinting) and targeted analysis of food volatiles; attention is focused not only on its potential in such applications, but also on how recent advances in comprehensive Two-Dimensional Gas Chromatography with mass spectrometry will potentially be important for food analysis. Additionally, emphasis is devoted to the many instances in which straightforward Gas Chromatography with mass spectrometry is a sufficiently-powerful analytical tool. Finally, possible future scenarios in the comprehensive Two-Dimensional Gas Chromatography with mass spectrometry food analysis field are discussed.
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Modulators for comprehensive Two-Dimensional Gas Chromatography
TrAC Trends in Analytical Chemistry, 2011Co-Authors: Peter Quinto Tranchida, Paola Dugo, Giorgia Purcaro, Luigi MondelloAbstract:Abstract The analytical benefits of comprehensive Two-Dimensional Gas Chromatography (GC × GC) methods have been exploited and emphasized in the past two decades. The unexpectedly complex nature of many real-world samples amenable to GC analysis has been elucidated through the enhanced resolving power of GC × GC. Simple but fundamental devices, called modulators, enable continuous heart-cutting and re-injection, without which GC × GC analysis cannot be achieved. The present review focuses on the history (1991–2010), and present trends and future prospects for GC × GC modulation. We provide detailed descriptions and set out the advantages and the disadvantages of the most significant thermal and pneumatic modulators.
