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Huang H, Wang Z, Dai C, Wu H, Guo J, Wang C, Zhang X. Species profile and reactivity of volatile organic compounds emission in solvent uses, industry activities and from vehicular tunnels. J Environ Sci (China) 2024; 135:546-559. [PMID: 37778826 DOI: 10.1016/j.jes.2022.08.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 08/28/2022] [Accepted: 08/30/2022] [Indexed: 10/03/2023]
Abstract
A survey was conducted of the volatile organic compounds (VOCs) released from sources of solvent use, industry activities and vehicle emissions in Guiyang, a capital city of China. Samples were collected by canisters and analyzed by GC-MS-FID. The species profiles of VOCs emitted from sources were obtained. Results showed that xylenes, ethylbenzene, acetone and dichloromethane were the characteristics species for painting, 2-propanol and ethyl acetate for printing, α-pinene for solid wood furniture manufacturing, and 2-butanone for biscuit baking. These characteristics species could be as tracers for the sources respectively. In most of samples from the solvent use, the benzene/toluene (B/T) ratio was less than 0.3, indicating that the ratio could be as the indicator for tracing the solvent use related sources. The results also suggested that the toluene/xylene (T/X) ratio be as the indicator to distinguish the VOCs sources of painting (<2) from the printing (>2). Aromatics contributed the most to ozone formation potential (OFP) of most painting and non-paper printing sources, and oxygen-containing VOCs (OVOCs) were major species contributing to OFP of the sources from food production and paper printing. The OFP of the VOCs emissions from vehicle in tunnels and from other manufactures were dominated by both aromatics and alkenes. The α-pinene could explain 56.94% and 32.54% of total OFP of the VOCs sources from filing cabinet and solid wood furniture manufacturing, which was rarely been involved in previous studies of VOCs source profiles, indicating that the species of concern for VOCs sources are still insufficient at present.
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Affiliation(s)
- Haimei Huang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhangwei Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Chunhao Dai
- Hunan Agricultural University, Changsha 430106, China
| | - Hai Wu
- National Institute of Metrology, Beijing 100029, China.
| | - Jia Guo
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Chunjie Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoshan Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Chow HYJ, Górecki T. Second-Dimension Temperature Programming System for Comprehensive Two-Dimensional Gas Chromatography. Part 2: Technical Improvements and Compatibility with Flow Modulation and Time-of-Flight Mass Spectrometry. Anal Chem 2023; 95:8164-8171. [PMID: 37201205 DOI: 10.1021/acs.analchem.3c00093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The second-dimension (2D) temperature programming system (2DTPS) for comprehensive two-dimensional gas chromatography (GC × GC) described in Part 1 was updated and tested with the time-of-flight mass spectrometer (TOFMS) and flow modulator. Addition of a real-time clock and remote port allowed the 2DTPS to be a truly standalone system to be used with any GC × GC instrument. GC × GC reproducibility with the 2DTPS was tested with thermal and flow modulation, coupled with the TOFMS and/or FID to demonstrate compatibility with all typical GC × GC setups. An improvement in the match factor, reverse match factor, and signal-to-noise ratio was found when performing 2D temperature programming. Within-day and day-to-day reproducibility of the 2DTPS for the 1D retention time (≤0.04 and ≤0.05%), 2D retention time (≤0.36 and ≤0.52%), and peak area (≤2.47 and ≤3.37%) were acceptable, while providing flexibility in 2D optimization and improved peak capacity.
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Affiliation(s)
- Hei Yin J Chow
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Tadeusz Górecki
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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3
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Tian B, Gao S, Zhu Z, Zeng X, Liang Y, Yu Z, Peng P. Two-dimensional gas chromatography coupled to isotope ratio mass spectrometry for determining high molecular weight polycyclic aromatic hydrocarbons in sediments. J Chromatogr A 2023; 1693:463879. [PMID: 36822039 DOI: 10.1016/j.chroma.2023.463879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/12/2023] [Accepted: 02/16/2023] [Indexed: 02/21/2023]
Abstract
The accuracy of compound-specific isotope analysis (CSIA) of trace-level pollutants in complex environmental samples has always been limited by two main challenges: poor chromatographic separation and insufficient amounts of analytes. In this study, a two-dimensional gas chromatography-isotope ratio mass spectrometry (2DGC-IRMS) system was constructed for compound-specific δ13C analysis of high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) in estuarine/marine sediments. This construction occurred through hyphenating an extra gas chromatography system (GC) to a conventional GC-IRMS using a commercially available multi-column switching-cryogenic trapping system (MCS-CTS). Compared with the previous 2DGC-IRMS strategy, which utilizes a Deans Switch device, the newly implemented 2DGC-IRMS scheme resulted in online purification of target analytes as well as enriched them online via duplicate injection and cryogenic trapping in CTS; this resultingly lowered the limits of detection (LOD) of CSIA. To improve the sample transfer efficiency to the IRMS, a broader-bore and longer fused-silica capillary was utilized to replace the original sample capillary running from the sample open split to the IRMS. A ẟ13C analysis of PAH standards showed accurate ẟ13C values, and high precisions (standard deviations 0.13-0.37%) were achieved, with the LOD of HMW-PAHs reduced to at least 1.0 mg/L (i.e., 0.07 to 0.09 nmol carbon per compound on-column). The successful application of this newly developed 2DGC-IRMS scheme provides a practical solution for the reliable CSIA of trace-level pollutants in complex environmental samples that cannot be measured using the conventional GC-IRMS system.
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Affiliation(s)
- Boyang Tian
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shutao Gao
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China.
| | - Zhanjun Zhu
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiangying Zeng
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
| | - Yi Liang
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
| | - Zhiqiang Yu
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
| | - Ping'an Peng
- State Key Laboratory of Organic Geochemistry, Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
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da Silva CM, Siciliano B, Dantas G, Arbilla G. An improvement of method TO-15A, aided by heart-cutting multidimensional gas chromatography, for the analysis of C2-C12 hydrocarbons in atmospheric samples. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Huang H, Wang Z, Dai C, Guo J, Zhang X. Volatile organic compounds emission in the rubber products manufacturing processes. ENVIRONMENTAL RESEARCH 2022; 212:113485. [PMID: 35577006 DOI: 10.1016/j.envres.2022.113485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Volatile organic compounds (VOCs) emission from rubber products manufacture processes, mixing, shaping and vulcanization were investigated in four rubber products factories in China. The source emission air was passively sampled by pre-vacuumized stainless steel canister and analyzed by gas chromatography-mass spectrometry-flame ionization detection (GC/MS-FID). The species profile of 107 VOCs in the emission processes were obtained. We calculated the photochemical ozone formation potential (OFP) and carcinogenic risk (CR) of the VOCs for each manufacture process. The results showed that mixing process mainly released dichloromethane (14.53%), carbon disulfide (CS2) (6.88%), styrene (5.72%), 4-methyl-2-pentanone (5.22%) and naphthalene (3.69%) for solvents used and raw rubber degradation in the process. The C6-C8 alkanes, especially heptane and isomers of heptane (44.71%), were dominated in shaping process. The major species released from vulcanization process were carbon disulfide (29.72%), naphthalene (8.17%), acetone (7.73%) and dichloromethane (4.26%). VOCs emitted from vulcanization process had the highest OFP, which contributed by naphthalene, m/p-xylene, o-xylene and carbon disulfide. VOCs emission from mixing process had the highest CR, and 1,2-dibromoethane, 1,2-dichlorethane and 1,3-butadiene were the main contributors to CR. We also estimated the total VOCs emissions into the atmosphere from tires manufacturing in China, which were 7.58 × 105 t in 2018 and contributed about 9% of total industry processes VOCs emissions.
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Affiliation(s)
- Haimei Huang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhangwei Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Chunhao Dai
- Hunan Agricultural University, Changsha, 430106, China
| | - Jia Guo
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Xiaoshan Zhang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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Unveiling Chemical Cues of Insect-Tree and Insect-Insect Interactions for the Eucalyptus Weevil and Its Egg Parasitoid by Multidimensional Gas Chromatographic Methods. Molecules 2022; 27:molecules27134042. [PMID: 35807301 PMCID: PMC9268296 DOI: 10.3390/molecules27134042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/17/2022] [Accepted: 06/17/2022] [Indexed: 02/01/2023] Open
Abstract
Multidimensional gas chromatography is, presently, an established and powerful analytical tool, due to higher resolving power than the classical 1D chromatographic approaches. Applied to multiple areas, it allows to isolate, detect and identify a larger number of compounds present in complex matrices, even in trace amounts. Research was conducted to determine which compounds, emitted by host plants of the eucalyptus weevil, Gonipterus platensis, might mediate host selection behavior. The identification of a pheromone blend of G. platensis is presented, revealing to be more attractive to weevils of both sexes, than the individual compounds. The volatile organic compounds (VOCs) were collected by headspace solid phase microextraction (HS-SPME), MonoTrapTM disks, and simultaneous distillation-extraction (SDE). Combining one dimensional (1D) and two-dimensional (2D) chromatographic systems—comprehensive and heart-cut two-dimensional gas chromatography (GC×GC and H/C-MD-GC, respectively) with mass spectrometry (MS) and electroantennographic (EAD) detection, enabled the selection and identification of pertinent semiochemicals which were detected by the insect antennal olfactory system. The behavioral effect of a selected blend of compounds was assessed in a two-arm olfactometer with ten parallel walking chambers, coupled to video tracking and data analysis software. An active blend, composed by cis and trans-verbenol, verbenene, myrtenol and trans-pinocarveol was achieved.
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Cucinotta L, De Grazia G, Micalizzi G, Bontempo L, Camin F, Mondello L, Sciarrone D. Simultaneous evaluation of the enantiomeric and carbon isotopic ratios of Cannabis sativa L. essential oils by multidimensional gas chromatography. Anal Bioanal Chem 2022; 414:5643-5656. [PMID: 35389094 DOI: 10.1007/s00216-022-04035-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 03/14/2022] [Accepted: 03/21/2022] [Indexed: 11/26/2022]
Abstract
Recent times have witnessed an upsurge of interest in hemp and hemp-derived products, as driven by the scientific findings specific to the pharmacological properties of Cannabis sativa L. and its constituents. There has been evidence that the terpene profile, along with the cannabinoid content, produces in humans the effects associated with different strains, beyond fragrance perception. A great deal of effort has been put into developing analytical approaches to strengthen the scientific knowledge on cannabis essential oil composition and provide effective tools for ascertaining the authenticity of commercial cannabis samples. For this concern, enantio-selective-GC-C-IRMS has proven to be effective for assessing the ranges characteristic of the genuine samples and detecting any fraudulent additions. This research aimed at providing for the first time the enantiomeric and isotopic ratios of target terpenes in cannabis essential oils, obtained from microwave-assisted hydro-distillation from the fresh and dried inflorescences of different cannabis varieties. Implementing multidimensional gas chromatography separation was mandatory prior to detection, in order to obtain accurate δ13C values and enantiomeric data from completely separated peaks. For this purpose, a heart-cut method was developed, based on the coupling of an apolar first dimension column to a secondary chiral cyclodextrin-based stationary phase. Afterwards, the data gathered from enantio-selective-MDGC-C-IRMS/qMS analysis of a set of genuine samples were used to evaluate the quality of nineteen commercial cannabis essential oils purchased from local stores. Remarkably, the data in some cases evidenced enantiomeric ratios and δ13C values outside the typical ranges of genuine oils. Such findings suggest the usefulness of the method developed to ascertain the genuineness and quality of cannabis essential oils.
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Affiliation(s)
- Lorenzo Cucinotta
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy
- Traceability Unit, Research and Innovation Centre, Fondazione Edmund Mach, San Michele All'Adige, via Mach 1, 38098, Trento, TN, Italy
| | - Gemma De Grazia
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy
| | - Giuseppe Micalizzi
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy
| | - Luana Bontempo
- Traceability Unit, Research and Innovation Centre, Fondazione Edmund Mach, San Michele All'Adige, via Mach 1, 38098, Trento, TN, Italy
| | - Federica Camin
- Traceability Unit, Research and Innovation Centre, Fondazione Edmund Mach, San Michele All'Adige, via Mach 1, 38098, Trento, TN, Italy
- Center Agriculture Food Environment (C3A), University of Trento, San Michele All'Adige, Via Mach 1, 38010, Trento, TN, Italy
- Vienna International Centre, International Atomic Energy Agency, PO Box 100, 1400, Vienna, Austria
| | - Luigi Mondello
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy
- Chromaleont S.R.L., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy
- Department of Sciences and Technologies for Human and Environment, University Campus Bio-Medico of Rome, Rome, Italy
| | - Danilo Sciarrone
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168, Messina, Italy.
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Cucinotta L, De Grazia G, Salerno TMG, Donnarumma D, Donato P, Sciarrone D, Mondello L. Overcoming the lack of reliability associated to monodimensional gas chromatography coupled to isotopic ratio mass spectrometry data by heart-cut two-dimensional gas chromatography. J Chromatogr A 2021; 1655:462473. [PMID: 34464784 DOI: 10.1016/j.chroma.2021.462473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 11/17/2022]
Abstract
The use of IRMS as a GC detector has a history going back decades, however the critical issue of wrong δ13C measurements resulting from impure peaks has been often underestimated. To this regard, multidimensional separation techniques are effective tools to improve the reliability of the data, with respect to those obtained after monodimensional analysis. The present research aims to draw attention to one critical issue, related to the reliability of the δ13C data obtained by means of monodimensional GC-C-IRMS. Although already known from the literature, such aspect has been greatly overlooked, as is reflected in the few papers reporting the use of MDGC, among the plethora of published research dealing with GC-C-IRMS applications. Hereby, a set of natural samples of complex composition were analysed to investigate the presence of minor or even undetected coelutions, and to which extent it affected the isotope ratio determination. Apart from chromatographic effects, and issues related to analytes conversion to CO2 prior to IRMS measurement, unpredictable co-elutions with compounds, either resulting from oxidation or intentionally added in fraudulent practices, could also contribute to a shift of the δ13C data, up to 10‰ and higher. Last, the influence of column bleed was investigated, as affecting the determination of the δ13C data for compounds that were eluted at high temperatures. It was finally demonstrated by the selected key studies that implementation of MDGC separation is mandatory to prevent the aforementioned issues, aiming to guarantee accurate results. In the light of the above conclusions, and considering the level of automation of heart-cut devices nowadays available, routine practice of MDGC results highly recommendable in any IRMS applications.
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Affiliation(s)
- Lorenzo Cucinotta
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy; Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, San Michele all'Adige, 38010, Italy
| | - Gemma De Grazia
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Tania Maria Grazia Salerno
- BeSep s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental, Sciences, University of Messina, 98168 Messina, Italy
| | - Danilo Donnarumma
- Chromaleont s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Paola Donato
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, 98125 Messina, Italy
| | - Danilo Sciarrone
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy.
| | - Luigi Mondello
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy; BeSep s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental, Sciences, University of Messina, 98168 Messina, Italy; Chromaleont s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
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Compound-specific carbon isotope analysis of volatile organic compounds in complex soil extracts using purge and trap concentration coupled to heart-cutting two-dimensional gas chromatography-isotope ratio mass spectrometry. J Chromatogr A 2021; 1655:462480. [PMID: 34479096 DOI: 10.1016/j.chroma.2021.462480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 07/22/2021] [Accepted: 08/14/2021] [Indexed: 11/20/2022]
Abstract
Compound-specific carbon isotope analysis (CSIA) is a powerful tool to track the origin and fate of organic subsurface contaminants including petroleum and chlorinated hydrocarbons and is typically applied to water samples. However, soil can form a significant contaminant reservoir. In soil samples, it can be challenging to recover sufficient amounts of volatile organic compounds (VOC) to perform CSIA. Soil samples often contain complex contaminant mixtures and gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) is highly dependent on good chromatographic separation due to the conversion to a single analyte. To extend the applicability of CSIA to complex volatile organic compound mixtures in soil samples, and to recover sufficient amounts of target compounds for carbon CSIA, we compared two soil extraction solvents, tetraglyme (TGDE) and methanol, and developed a heart-cutting two-dimensional GC-GC-C-IRMS method. We used purge & trap concentration of solvent-water mixtures to increase the amount of analyte delivered to the column and thus lower method detection limits. We optimized purge & trap and chromatographic parameters for twelve target compounds, including one suffering from poor purge efficiency. By using a 30 m thick-film non-polar column in the first and a 15 m polar column in the second dimension, we achieved good chromatographic separation for the target compounds in difficult matrices and high accuracy (trueness and precision) for carbon isotopic analysis. Tetraglyme extraction was shown to offer advantages over methanol for purge & trap concentration, leading to lower target compound method detection limits for CSIA of soil samples. The applicability of the developed method was demonstrated for a case study on soil extracts from a former manufacturing facility. Our approach extends the applicability of CSIA to an important matrix that often controls the long-term fate of contaminants in the subsurface.
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Mun H, Townley HE. Nanoencapsulation of Plant Volatile Organic Compounds to Improve Their Biological Activities. PLANTA MEDICA 2021; 87:236-251. [PMID: 33176380 DOI: 10.1055/a-1289-4505] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Plant volatile organic compounds (volatiles) are secondary plant metabolites that play crucial roles in the reproduction, defence, and interactions with other vegetation. They have been shown to exhibit a broad range of biological properties and have been investigated for antimicrobial and anticancer activities. In addition, they are thought be more environmentally friendly than many other synthetic chemicals 1. Despite these facts, their applications in the medical, food, and agricultural fields are considerably restricted due to their volatilities, instabilities, and aqueous insolubilities. Nanoparticle encapsulation of plant volatile organic compounds is regarded as one of the best strategies that could lead to the enhancement of the bioavailability and biological activity of the volatile compounds by overcoming their physical limitations and promoting their controlled release and cellular absorption. In this review, we will discuss the biosynthesis and analysis of plant volatile organic compounds, their biological activities, and limitations. Furthermore, different types of nanoparticle platforms used to encapsulate the volatiles and the biological efficacies of nanoencapsulated volatile organic compounds will be covered.
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Affiliation(s)
- Hakmin Mun
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | - Helen E Townley
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
- Department of Engineering Science, University of Oxford, Oxford, UK
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Rasheed DM, Serag A, Abdel Shakour ZT, Farag M. Novel trends and applications of multidimensional chromatography in the analysis of food, cosmetics and medicine bearing essential oils. Talanta 2021; 223:121710. [DOI: 10.1016/j.talanta.2020.121710] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/22/2020] [Accepted: 09/24/2020] [Indexed: 12/17/2022]
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12
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Janta P, Pinyo D, Yodta Y, Vasasiri P, Weidenbach M, Pursch M, Yang XG, Kulsing C. A multi-location peak parking approach for calculation of second dimensional retention indices for improved volatile compound identification with cryogen-free comprehensive heart-cut two-dimensional gas chromatography. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2021; 13:124-132. [PMID: 33319877 DOI: 10.1039/d0ay01976c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Comprehensive heart-cut multidimensional gas chromatography (CH/C MDGC) without a cryogenic trapping device was developed with an established approach for calculation of first and second dimensional retention indices (1I and 2I) for improved compound identification. A first dimensional (1D) DB-1MS column (60 m) and a second dimensional (2D) DB-WAX column (60 m) were applied with a Deans switch (DS) using a constant H/C window of 0.2 min and a periodic multiple heartcut strategy comprising 225H/C throughout the CH/C. 1I was calculated based on comparison of the middle of the heartcut time with the alkane retention times on the 1D column. A multi-location peak parking approach using sixteen sets of automated injections of alkane references was also established with the least square curve fitting method for construction of the alkane isovolatility curves which were applied for 2I calculation. The untargeted compound analysis of a perfume sample was then performed according to comparison with the libraries of mass spectra, 1I and 2I. The CH/C MDGC system with a 25 h analysis time showed a peak capacity (nc) of 9198 and 128 separated peaks with 71 compounds successfully identified according to MS, 1I and 2I library match under the established error approximation criteria. Furthermore, relationship between the analysis time and number of separated peaks was proposed based on the set of 84 identifiable compounds. With the compensation of lower separation performance and greater I errors, the analysis time could be reduced by applying a 2.5 min H/C window with a total analysis time of 2 h and nc of 1134.
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Affiliation(s)
- Pannipa Janta
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
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Momotko M, Łuczak J, Przyjazny A, Boczkaj G. First deep eutectic solvent-based (DES) stationary phase for gas chromatography and future perspectives for DES application in separation techniques. J Chromatogr A 2020; 1635:461701. [PMID: 33254003 DOI: 10.1016/j.chroma.2020.461701] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 12/27/2022]
Abstract
The 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 reveal that the synthesized DES is a stationary phase of medium polarity. A detailed retention characteristic was determined for a number of groups of chemical compounds, including aromatic hydrocarbons, alcohols, ketones, sulfides and thiophene derivatives. The synthesized DES was found to have a high selectivity towards alcohols. At the same time, the investigated stationary phase was found to have specific interactions with some analytes. For example, a stronger retention was observed for 1-hexanol and 1-heptanol compared to other alcohols. Retention times of these two alcohols are longer by 191% and 300%, respectively, relative to the expected value based on their boiling point. Such an increased retention is caused by a synergistic effect of various kinds of interactions - the possibility of formation of hydrogen bonds between the DES and the hydroxyl group of alcohols and hydrophobic interactions of alkyl chains of the DES with the alkyl chain of alcohols. The ability to modify properties of DESs by replacement of HBA or HBD with a different chemical compound or by dissolving in DES macromolecular substances makes the proposed stationary phase highly flexible. In addition to using the developed DES in chromatographic techniques, the retention data collected indicate the possibility of its application to other separation techniques, i.e. extractive distillation.
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Affiliation(s)
- Malwina Momotko
- Gdansk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80 - 233 Gdansk, G. Narutowicza St. 11/12, Poland
| | - Justyna Łuczak
- Gdansk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80 - 233 Gdansk, G. Narutowicza St. 11/12, Poland
| | | | - Grzegorz Boczkaj
- Gdansk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80 - 233 Gdansk, G. Narutowicza St. 11/12, Poland.
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Bio-Inspired Strategies for Improving the Selectivity and Sensitivity of Artificial Noses: A Review. SENSORS 2020; 20:s20061803. [PMID: 32214038 PMCID: PMC7146165 DOI: 10.3390/s20061803] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/18/2020] [Accepted: 03/21/2020] [Indexed: 12/20/2022]
Abstract
Artificial noses are broad-spectrum multisensors dedicated to the detection of volatile organic compounds (VOCs). Despite great recent progress, they still suffer from a lack of sensitivity and selectivity. We will review, in a systemic way, the biomimetic strategies for improving these performance criteria, including the design of sensing materials, their immobilization on the sensing surface, the sampling of VOCs, the choice of a transduction method, and the data processing. This reflection could help address new applications in domains where high-performance artificial noses are required such as public security and safety, environment, industry, or healthcare.
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NAKAGAMI K, SUMIYA O, TAKAHASHI K, KOBAYASHI A, UETA I, SAITO Y. On-Line Coupling of Gas Chromatography-Gas Chromatography for the Determination of Coumarin in Kerosene. CHROMATOGRAPHY 2019. [DOI: 10.15583/jpchrom.2019.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Koki NAKAGAMI
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology
| | - Ohjiro SUMIYA
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology
| | - Kazuya TAKAHASHI
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology
| | - Akira KOBAYASHI
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology
| | - Ikuo UETA
- Department of Applied Chemistry, University of Yamanashi
| | - Yoshihiro SAITO
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology
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16
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Martínez RM, Barba C, Robredo S, Herraiz M. Improving enantiomeric resolutions by avoiding peak distortion effects in on-line coupled liquid chromatography to gas chromatography. Chirality 2019; 31:879-891. [PMID: 31429160 DOI: 10.1002/chir.23121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/12/2019] [Accepted: 07/22/2019] [Indexed: 11/05/2022]
Abstract
In this work, we study the effect of different variables affecting elution profile distortion on the enantiomeric resolution eventually achievable when working with on-line coupled liquid chromatography to gas chromatography (LC-GC). Specifically, the proposed configuration combines achiral reversed-phase liquid chromatography (RPLC) and chiral gas chromatography (enantio-GC), with heptakis-(2,3,6-tri-O-methyl)-β-cyclodextrin as enantioselective stationary phase to analyse target fractions transferred (from LC to GC) via the through oven transfer adsorption desorption (TOTAD) interface. The high degree of orthogonality resulting from the combination of two chromatographic columns having very different separation mechanisms (and also requiring mobile phases in distinct physical states), as well as integration of the sample preparation step in the first dimension of the system, significantly contributed to exploit the performance of the proposed two-dimensional approach. Occasional adverse effects, which may result in severe peak distortions during LC-GC analysis and could be explained by flow instabilities due to viscous fingering, are circumvented by using the outstanding capacity of the TOTAD interface for achieving effective elimination of the eluent arriving from the LC preseparation.
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Affiliation(s)
- Rosa M Martínez
- Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Carmen Barba
- Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Sergio Robredo
- Laboratorio Arbitral Agroalimentario (LAA), Ministerio de Agricultura, Alimentación y Medio Ambiente, Madrid, Spain
| | - Marta Herraiz
- Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
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Luong J, Hua Y, Gras R, Shellie RA. Uniformity and Sensitivity Improvements in Comprehensive Two-Dimensional Gas Chromatography Using Flame Ionization Detection with Post-Column Reaction. Anal Chem 2019; 91:11223-11230. [PMID: 31393704 DOI: 10.1021/acs.analchem.9b02159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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 intercolumn connectivity. Chromatographic fidelity was in the practical domain of comprehensive 2D gas chromatography. Typical peak widths at half-height using the described approach ranged from 165 to 235 ms for probe compounds with retention factors spanning 5 < k < 40.
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Affiliation(s)
- Jim Luong
- Dow Chemical Canada ULC , Highway 15 , Fort Saskatchewan , Alberta T8L 2P4 , Canada.,Australian Centre for Research on Separation Science (ACROSS) , University of Tasmania , Private Bag 75 , Hobart , Tasmania 7001 , Australia
| | - Yujuan Hua
- Dow Chemical Canada ULC , Highway 15 , Fort Saskatchewan , Alberta T8L 2P4 , Canada
| | - Ronda Gras
- Dow Chemical Canada ULC , Highway 15 , Fort Saskatchewan , Alberta T8L 2P4 , Canada.,Australian Centre for Research on Separation Science (ACROSS) , University of Tasmania , Private Bag 75 , Hobart , Tasmania 7001 , Australia
| | - Robert A Shellie
- Centre for Advanced Sensory Science (CASS), School of Exercise and Nutrition Sciences , Deakin University , Burwood Highway , Burwood , Victoria 3125 , Australia
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Sciarrone D, Schepis A, De Grazia G, Rotondo A, Alibrando F, Cipriano RR, Bizzo H, Deschamps C, Sidisky LM, Mondello L. Collection and identification of an unknown component from Eugenia uniflora essential oil exploiting a multidimensional preparative three-GC system employing apolar, mid-polar and ionic liquid stationary phases. Faraday Discuss 2019; 218:101-114. [PMID: 31120047 DOI: 10.1039/c8fd00234g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The present research deals with the collection and structural elucidation of an unknown component, accounting for about 35% of the essential oil obtained upon distillation of the leaves of Eugenia uniflora L., harvested during summer (January, 2017) in Paraná State (Southern Brazil). A multidimensional gas chromatographic preparative system, based on the coupling of three GC systems equipped with apolar, PEG and ionic liquid-based stationary phases, was successfully applied for the isolation of the chromatographic band relative to the unknown molecule. The use of wide-bore columns allowed for an increased sample capacity compared to conventional micro-bore columns, thus the injection of a neat sample was feasible, greatly reducing the total collection time. A higher chromatographic efficiency was afforded by the use of a multidimensional approach in the heart-cut mode, exploiting the different selectivity of three stationary phases, which ensured the attainment of a highly pure fraction. In only five runs, more than 3 milligrams were collected, with an average purity greater then 95%. Finally, the unknown component was subjected to nuclear magnetic resonance spectroscopy, mass spectrometry and condensed phase Fourier-transform infrared spectroscopy, leading to the identification of 6-ethenyl-6-methyl-3,5-di(prop-1-en-2-yl)cyclohex-2-en-1-one. The presented approach has been demonstrated to be effective for the isolation and structural elucidation of unknown molecules in complex samples, which will allow for further in-depth studies, like biological evaluation or pharmacological tests.
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Affiliation(s)
- Danilo Sciarrone
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy.
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Improving the resolution of overlapping peaks by heartcut two-dimensional countercurrent chromatography with the same solvent system in both dimensions. J Chromatogr A 2019; 1596:142-151. [DOI: 10.1016/j.chroma.2019.03.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/14/2019] [Accepted: 03/05/2019] [Indexed: 11/19/2022]
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20
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Development and validation of a multidimensional gas chromatography/combustion/isotope ratio mass spectrometry-based test method for analyzing urinary steroids in doping controls. Anal Chim Acta 2018; 1030:105-114. [DOI: 10.1016/j.aca.2018.05.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/30/2018] [Accepted: 05/03/2018] [Indexed: 11/18/2022]
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21
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Multidimensional Gas Chromatography in Essential Oil Analysis. Part 1: Technical Developments. Chromatographia 2018. [DOI: 10.1007/s10337-018-3649-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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22
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Gras R, Luong J, Shellie RA. Miniaturized micromachined gas chromatography with universal and selective detectors for targeted volatile compounds analysis. J Chromatogr A 2018; 1573:151-155. [DOI: 10.1016/j.chroma.2018.08.064] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/24/2018] [Accepted: 08/31/2018] [Indexed: 12/29/2022]
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23
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Sciarrone D, Schepis A, Zoccali M, Donato P, Vita F, Creti D, Alpi A, Mondello L. Multidimensional Gas Chromatography Coupled to Combustion-Isotope Ratio Mass Spectrometry/Quadrupole MS with a Low-Bleed Ionic Liquid Secondary Column for the Authentication of Truffles and Products Containing Truffle. Anal Chem 2018; 90:6610-6617. [DOI: 10.1021/acs.analchem.8b00386] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Danilo Sciarrone
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, Viale Annunziata, 98168, Messina, Italy
| | - Antonino Schepis
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, Viale Annunziata, 98168, Messina, Italy
| | - Mariosimone Zoccali
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, Viale Annunziata, 98168, Messina, Italy
| | - Paola Donato
- Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali, University of Messina, via Consolare Valeria, 98125, Messina, Italy
| | - Federico Vita
- Department of Agriculture, Food and Environment, University of Pisa, Via Mariscoglio 34, 56124, Pisa, Italy
| | - Donato Creti
- Enrico Giotti S.p.A., a Subsidiary of McCormick & Company, Inc., Via Pisana 592, 50018, Scandicci, Florence, Italy
| | - Amedeo Alpi
- Dipartimento di Scienze Agrarie, Alimentari, Agro-ambientali, Laboratorio di Fisiologia Vegetale, University of Pisa, Via Mariscoglio 34, 56124, Pisa, Italy
| | - Luigi Mondello
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, Viale Annunziata, 98168, Messina, Italy
- Chromaleont S.r.l., Via Leonardo Sciascia CoopFede, Pal. B, 98168, Messina, Italy
- University Campus Bio-Medico of Rome, via Álvaro del Portillo 21, 00128, Rome, Italy
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24
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Waktola HD, Kulsing C, Nolvachai Y, Marriott PJ. High temperature multidimensional gas chromatographic approach for improved separation of triacylglycerols in olive oil. J Chromatogr A 2018; 1549:77-84. [DOI: 10.1016/j.chroma.2018.03.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 03/06/2018] [Accepted: 03/17/2018] [Indexed: 11/25/2022]
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25
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Tu Q, Qi W, Zhao J, Zhang L, Guo Y. Quantification ethyl carbamate in wines using reaction-assisted-extraction with 9-xanthydrol and detection by heart-cutting multidimensional gas chromatography-mass spectrometry. Anal Chim Acta 2018; 1001:86-92. [DOI: 10.1016/j.aca.2017.11.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/03/2017] [Accepted: 11/07/2017] [Indexed: 01/03/2023]
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26
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Gas chromatographic sulphur speciation in heavy crude oil using a modified standard D5623 method and microfluidic Deans switching. J Chromatogr A 2017; 1530:241-246. [DOI: 10.1016/j.chroma.2017.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/02/2017] [Accepted: 11/03/2017] [Indexed: 11/23/2022]
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27
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Lim H, Ahmed TM, Bergvall C, Westerholm R. Automated clean-up, separation and detection of polycyclic aromatic hydrocarbons in particulate matter extracts using a 2D-LC/2D-GC system: a method translation from two FIDs to two MS detectors. Anal Bioanal Chem 2017; 409:5619-5629. [PMID: 28741108 PMCID: PMC5583270 DOI: 10.1007/s00216-017-0509-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/04/2017] [Indexed: 11/10/2022]
Abstract
An online two-dimensional (2D) liquid chromatography/2D gas chromatography system with two mass-selective detectors has been developed on the basis of a previous system with two flame ionization detectors. The method translation involved the change of carrier gas from hydrogen to helium, column dimension and detectors. The 2D system with two mass-selective detectors was validated with use of polycyclic aromatic hydrocarbon (PAH) standards and two standard reference materials from air and diesel exhaust. Furthermore, the system was applied to a real sample, wood smoke particulates. The PAH values determined correlated well with the previous data and those from the National Institute of Standards and Technology. The system enhanced the benefits of the previous system, which were limited by the low detectability and lack of mass selectivity. This study shows an automated 2D system that is valid for PAH analysis of complex environmental samples directly from crude extracts. Graphical Abstract Schematic illustration showing on-line clean-up, separation and detection using 2D-LC/2D-GC/MS.
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Affiliation(s)
- Hwanmi Lim
- Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, 106 91, Stockholm, Sweden
| | - Trifa M Ahmed
- Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, 106 91, Stockholm, Sweden
- Livsmedelsverket, Box 622, 751 26, Uppsala, Sweden
| | - Christoffer Bergvall
- Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, 106 91, Stockholm, Sweden
- Department of Ecology and Genetics, Limnology, Uppsala University, 752 36, Uppsala, Sweden
| | - Roger Westerholm
- Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, 106 91, Stockholm, Sweden.
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Said-Ahmad W, Wong K, Mcnall M, Shawar L, Jacksier T, Turich C, Stankiewicz A, Amrani A. Compound-Specific Sulfur Isotope Analysis of Petroleum Gases. Anal Chem 2017; 89:3199-3207. [PMID: 28194958 DOI: 10.1021/acs.analchem.6b05131] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe a simple, sensitive, and robust method for sulfur isotope ratio (34S/32S) analysis of ppm-level organic sulfur compounds (OSCs) in the presence of percent-level H2S. The method uses a gas chromatograph (GC) coupled with a multicollector inductively coupled plasma mass spectrometer (MC-ICPMS). The GC, equipped with a gas inlet and a valve that transfers the H2S to a thermal conductivity detector (TCD), enables a precise heart cut and prevents the saturation of the MC-ICPMS. The sensitivity and accuracy of the method are better than 0.3‰ for OSCs at a concentration of 25 pmol or 1.4 ppm, and better than 0.5‰ for concentrations ≥0.7 ppm of OSCs. An order of magnitude increase in sensitivity, with no effect on accuracy, can be achieved if the loop volume (0.5 mL) is changed to 5 mL. High concentrations of methane (95% v/v) and/or H2S (20% v/v) had no effect (within 0.5‰) on the precision and accuracy of the gas sample containing 2 ppm of OSCs after heart cut. The applicability and robustness of this method are demonstrated on a gas sample (10% v/v H2S) that was produced by pyrolysis of sulfur-rich kerogen. The results show good precision and reveal sulfur isotope variability between individual OSCs that may represent key processes during formation and degradation of OSCs.
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Affiliation(s)
- Ward Said-Ahmad
- Earth Sciences Institute, Hebrew University , Jerusalem 91904, Israel
| | - Kenneth Wong
- Air Liquide, Delaware Research & Technology Center , Newark, Delaware 19702, United States
| | - Monaca Mcnall
- Air Liquide, Delaware Research & Technology Center , Newark, Delaware 19702, United States
| | - Lubna Shawar
- Earth Sciences Institute, Hebrew University , Jerusalem 91904, Israel
| | - Tracey Jacksier
- Air Liquide, Delaware Research & Technology Center , Newark, Delaware 19702, United States
| | | | | | - Alon Amrani
- Earth Sciences Institute, Hebrew University , Jerusalem 91904, Israel
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Characterization of thermal desorption with the Deans-switch technique in gas chromatographic analysis of volatile organic compounds. J Chromatogr A 2016; 1462:107-14. [PMID: 27492597 DOI: 10.1016/j.chroma.2016.07.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/26/2016] [Accepted: 07/26/2016] [Indexed: 11/23/2022]
Abstract
This study presents a novel application based on the Deans-switch cutting technique to characterize the thermal-desorption (TD) properties for gas chromatographic (GC) analysis of ambient volatile organic compounds (VOCs). Flash-heating of the sorbent bed at high temperatures to desorb trapped VOCs to GC may easily produce severe asymmetric or tailing GC peaks affecting resolution and sensitivity if care is not taken to optimize the TD conditions. The TD peak without GC separation was first examined for the quality of the TD peak by analyzing a standard gas mixture from C2 to C12 at ppb level. The Deans switch was later applied in two different stages. First, it was used to cut the trailing tail of the TD peak, which, although significantly improved the GC peak symmetry, led to more loss of the higher boiling compounds than the low boiling ones, thus suggesting compound discrimination. Subsequently, the Deans switch was used to dissect the TD peak into six 30s slices in series, and an uneven distribution in composition between the slices were found. A progressive decrease in low boiling compounds and increase in higher boiling ones across the slices indicated severe inhomogeneity in the TD profile. This finding provided a clear evidence to answer the discrimination problem found with the tail cutting approach to improve peak symmetry. Through the use of the innovated slicing method based on the Deans-switch cutting technique, optimization of TD injection for highly resolved, symmetric and non-discriminated GC peaks can now be more quantitatively assessed and guided.
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Heshka NE, Hager DB. Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection. J Vis Exp 2015:e53416. [PMID: 26709594 DOI: 10.3791/53416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate interferences, a two dimensional column configuration is used, with a Deans switch employed to transfer hydrogen sulfide from the first to the second column (heart-cutting). Liquid crude samples are first separated on a dimethylpolysiloxane column, and light gases are heart-cut and further separated on a bonded porous layer open tubular (PLOT) column that is able to separate hydrogen sulfide from other light sulfur species. Hydrogen sulfide is then detected with a sulfur chemiluminescence detector, adding an additional layer of selectivity. Following separation and detection of hydrogen sulfide, the system is backflushed to remove the high-boiling hydrocarbons present in the crude samples and to preserve chromatographic integrity. Dissolved hydrogen sulfide has been quantified in liquid samples from 1.1 to 500 ppm, demonstrating wide applicability to a range of samples. The method has also been successfully applied for the analysis of gas samples from crude oil headspace and process gas bags, with measurement from 0.7 to 9,700 ppm hydrogen sulfide.
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Jacobs MR, Gras R, Nesterenko PN, Luong J, Shellie RA. Back-flushing and heart cut capillary gas chromatography using planar microfluidic Deans’ switching for the separation of benzene and alkylbenzenes in industrial samples. J Chromatogr A 2015; 1421:123-8. [DOI: 10.1016/j.chroma.2015.10.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/08/2015] [Accepted: 10/09/2015] [Indexed: 11/30/2022]
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33
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Sciarrone D, Pantò S, Ragonese C, Dugo P, Mondello L. Evolution and status of preparative gas chromatography as a green sample-preparation technique. Trends Analyt Chem 2015. [DOI: 10.1016/j.trac.2015.02.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Weijun Y. Direct determination of acrylamide in food by gas chromatography with nitrogen chemiluminescence detection. J Sep Sci 2015; 38:2272-7. [PMID: 25894309 DOI: 10.1002/jssc.201500060] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 11/06/2022]
Abstract
A method of gas chromatography with nitrogen chemiluminescence detection and using standard addition is described for the determination of acrylamide in heat-processed foods. Using a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation method removes the acrylamide precursors completely, and the risk of overestimating acrylamide concentration due to additional analyte formation in the hot gas chromatograph inlet is also avoided. Sample preparation is rapid and inexpensive. A Deans switch device is utilized to heart-cut acrylamide and to prevent interferences from the solvent and matrix from reaching the detector. The pre-column is backflushed at high temperature to maintain a clean baseline and shorten the cycle time compared to baking out the column. Quantitation using standard addition is employed for compensation of potential variability in the acrylamide extraction efficiency in acetonitrile. The limit of detection and the limit of the quantification obtained for this method are 27 and 81 μg/kg, respectively, in food samples (equivalent to 3.5 and 10.6 μg/L in acetonitrile, respectively), and the linear range is 76-9697 μg/kg in food samples (equivalent to 10-1280 μg/L in acetonitrile) with an R(2) value of 0.9999.
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Affiliation(s)
- Yao Weijun
- Agilent Technologies (Shanghai) Co. Ltd, Shanghai, 200131, China
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36
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Characterisation of the volatile fraction of aromatic caramel using heart-cutting multidimensional gas chromatography. Food Chem 2015; 167:281-9. [DOI: 10.1016/j.foodchem.2014.06.101] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/15/2014] [Accepted: 06/25/2014] [Indexed: 01/13/2023]
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Cordero C, Kiefl J, Schieberle P, Reichenbach SE, Bicchi C. Comprehensive two-dimensional gas chromatography and food sensory properties: potential and challenges. Anal Bioanal Chem 2014; 407:169-91. [DOI: 10.1007/s00216-014-8248-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 10/02/2014] [Accepted: 10/07/2014] [Indexed: 12/19/2022]
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38
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Ochiai N, Mitsui K, Sasamoto K, Yoshimura Y, David F, Sandra P. Multidimensional gas chromatography in combination with accurate mass, tandem mass spectrometry, and element-specific detection for identification of sulfur compounds in tobacco smoke. J Chromatogr A 2014; 1358:240-51. [PMID: 25087743 DOI: 10.1016/j.chroma.2014.06.106] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/26/2014] [Accepted: 06/30/2014] [Indexed: 01/08/2023]
Abstract
A method is developed for identification of sulfur compounds in tobacco smoke extract. The method is based on large volume injection (LVI) of 10μL of tobacco smoke extract followed by selectable one-dimensional ((1)D) or two-dimensional ((2)D) gas chromatography (GC) coupled to a hybrid quadrupole time-of-flight mass spectrometer (Q-TOF-MS) using electron ionization (EI) and positive chemical ionization (PCI), with parallel sulfur chemiluminescence detection (SCD). In order to identify each individual sulfur compound, sequential heart-cuts of 28 sulfur fractions from (1)D GC to (2)D GC were performed with the three MS detection modes (SCD/EI-TOF-MS, SCD/PCI-TOF-MS, and SCD/PCI-Q-TOF-MS). Thirty sulfur compounds were positively identified by MS library search, linear retention indices (LRI), molecular mass determination using PCI accurate mass spectra, formula calculation using EI and PCI accurate mass spectra, and structure elucidation using collision activated dissociation (CAD) of the protonated molecule. Additionally, 11 molecular formulas were obtained for unknown sulfur compounds. The determined values of the identified and unknown sulfur compounds were in the range of 10-740ngmg total particulate matter (TPM) (RSD: 1.2-12%, n=3).
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Affiliation(s)
- Nobuo Ochiai
- GERSTEL K.K., 1-3-1 Nakane, Meguro-ku, 152-0031 Tokyo, Japan.
| | - Kazuhisa Mitsui
- Japan Tobacco Inc., 6-2 Umegaoka Aoba-ku, Yokohama-shi, 227-8512 Kanagawa, Japan; The United Graduate School of Agricultural Sciences, Ehime University, 3-5-7 Tarumi, 790-8566 Matsuyama, Japan
| | - Kikuo Sasamoto
- GERSTEL K.K., 1-3-1 Nakane, Meguro-ku, 152-0031 Tokyo, Japan
| | - Yuta Yoshimura
- Japan Tobacco Inc., 6-2 Umegaoka Aoba-ku, Yokohama-shi, 227-8512 Kanagawa, Japan
| | - Frank David
- Research Institute for Chromatography, Kennedypark 26, 8500 Kortrijk, Belgium
| | - Pat Sandra
- Research Institute for Chromatography, Kennedypark 26, 8500 Kortrijk, Belgium
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Abstract
Multidimensional gas chromatography (MDGC) methods are high-resolution volatile chemical separation techniques, and comprise classical heart-cutting MDGC and its more recent incarnation, comprehensive 2D GC. Although available for a long period, MDGC approaches are still not widely practiced in the field of bioanalysis, possibly reflecting the general preference for regular GC versus MDGC approaches. With the recent introduction of ‘-omic’ techniques that emphasize global nontargeted profiling of metabolites within living systems, it is evident that MDGC is gaining momentum as a separation tool, since it offers very high resolution. By untangling metabolites within highly complex biological matrices, and expanding the metabolic coverage, MDGC plays a frontline role in ‘-omics’ based studies. This review highlights state-of-the-art MDGC approaches, and summarizes the recent developments in bioanalytics.
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40
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Chin ST, Marriott PJ. Multidimensional gas chromatography beyond simple volatiles separation. Chem Commun (Camb) 2014; 50:8819-33. [DOI: 10.1039/c4cc02018a] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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41
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Sciarrone D, Pantò S, Tranchida PQ, Dugo P, Mondello L. Rapid isolation of high solute amounts using an online four-dimensional preparative system: normal phase-liquid chromatography coupled to methyl siloxane-ionic liquid-wax phase gas chromatography. Anal Chem 2014; 86:4295-301. [PMID: 24725161 DOI: 10.1021/ac404078u] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study reports the recent evolution of a multidimensional GC-GC-GC preparative system, now combined with an online LC preseparation step, operated under normal phase conditions. It is herein shown that the four-dimensional instrument can collect sample components with a concentration lower than 10%, in a short time period, while maintaining a high level of analyte purity. The LC dimension allows (I) the injection of higher sample amounts, compared to "direct" GC injection; (II) a polarity-based preseparation, leading to the GC injection of simplified subsamples, and thus reducing the possibility of coelutions; (III) to eliminate the essential-oil "matrix", replacing it with the LC mobile phase (the GC system is more protected from potential contamination); (IV) the LC mobile phase is of much lower viscosity with respect to a pure, or highly concentrated essential oil, avoiding difficulties in the syringe sample withdrawal process, prior to GC injection. System optimization was performed by using standard solutions; in addition, a very complex sample, namely, vetiver essential oil, was subjected to the preparative process, with the scope of isolating two low-amount constituents (namely, α-amorphene and β-vetivone). The latter two sesquiterpenoids, which accounted for 1.7 and 4.0% of the sample (considering the volatiles), respectively, were successfully collected at the milligram level, in a one-day work period, with a purity degree in excess of 90%.
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Affiliation(s)
- Danilo Sciarrone
- Dipartimento di Scienze del Farmaco e dei Prodotti per la Salute, Università di Messina , Viale Annunziata, 98168 Messina, Italy
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42
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Tan HP, Wan TS, Min CLS, Osborne M, Ng KH. Quantitative analysis of fragrance in selectable one dimensional or two dimensional gas chromatography–mass spectrometry with simultaneous detection of multiple detectors in single injection. J Chromatogr A 2014; 1333:106-15. [DOI: 10.1016/j.chroma.2014.01.073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/24/2014] [Accepted: 01/27/2014] [Indexed: 01/17/2023]
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43
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Interpretation of comprehensive two-dimensional gas chromatography data using advanced chemometrics. Trends Analyt Chem 2014. [DOI: 10.1016/j.trac.2013.08.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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44
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Hildmann F, Kempe G, Speer K. Application of the precolumn back-flush technology in pesticide residue analysis: A practical view. J Sep Sci 2013; 36:2128-35. [DOI: 10.1002/jssc.201300007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 04/08/2013] [Accepted: 04/09/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Fanny Hildmann
- Department of Pesticides, Saxon; State Laboratory of Health and Veterinary Affairs; Dresden Germany
- Institute of Food Chemistry; Technical University Dresden; Dresden Germany
| | - Günther Kempe
- Department of Pharmacologically Active Substances, Saxon; State Laboratory of Health and Veterinary Affairs; Chemnitz Germany
| | - Karl Speer
- Institute of Food Chemistry; Technical University Dresden; Dresden Germany
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45
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Sciarrone D, Pantò S, Rotondo A, Tedone L, Tranchida PQ, Dugo P, Mondello L. Rapid collection and identification of a novel component from Clausena lansium Skeels leaves by means of three-dimensional preparative gas chromatography and nuclear magnetic resonance/infrared/mass spectrometric analysis. Anal Chim Acta 2013; 785:119-25. [DOI: 10.1016/j.aca.2013.04.069] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 04/15/2013] [Accepted: 04/30/2013] [Indexed: 11/24/2022]
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46
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Determination of trans fat in edible oils: current official methods and overview of recent developments. Anal Bioanal Chem 2013; 405:5759-72. [DOI: 10.1007/s00216-013-7005-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 10/26/2022]
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47
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Ghosh A, Bates CT, Seeley SK, Seeley JV. High speed Deans switch for low duty cycle comprehensive two-dimensional gas chromatography. J Chromatogr A 2013; 1291:146-54. [DOI: 10.1016/j.chroma.2013.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 10/27/2022]
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48
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Chen BX, Hung TY, Jian RS, Lu CJ. A multidimensional micro gas chromatograph employing a parallel separation multi-column chip and stop-flow μGC × μGCs configuration. LAB ON A CHIP 2013; 13:1333-1341. [PMID: 23381092 DOI: 10.1039/c2lc41179b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A dual-chip, multidimensional micro gas chromatographic module was designed, built and evaluated. Column chips were fabricated on a silicon wafer with an etched rectangular channel 100 μm (width) × 250 μm (depth) using a deep reactive ion etching (DRIE) process. The column chip for the first GC dimension was 3 m long and was coated with polydimethylsiloxane (DB-1) as the stationary phase. The columns on the second dimensional chip were etched with the same width and depth as the first chip, but the flow channel was split into three parallel columns, 1 m long, on the same sized silicon chip (i.e., 3 cm × 3 cm). These three parallel columns on the second chip were coated with polyethylene oxide (DB-Wax), trifluoropropylpolymethylsilicone (OV-210) and cyanopropylmethylphenylmethylpolysilicone (OV-225), accordingly, in order to provide diversified chromatographic retention. These two chips were connected via a stop-flow configuration to simultaneously generate multiple two-dimensional gas chromatograms for every analysis. This stop-flow μGC × μGCs design allowed the first column to function as a pre-separator and as a sequencing injector for the second parallel-separation chip. Fifteen volatile organic compounds with boiling points that ranged from 80-131 °C with various functional groups were tested using this μGC × μGCs module. Three discrete 2-D chromatograms were generated simultaneously, which demonstrated the advantages of simultaneously combining GC × GC with parallel separation GCs in microchip chromatography. The total traveling length in the column was only 4 m for each eluted peak and fully resolved separation was achieved through the cross reference among triplet 2-D chromatograms.
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Affiliation(s)
- Bo-Xun Chen
- Chemistry Department, National Taiwan Normal University, Ting-Chow Rd., Taipei, Taiwan
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49
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Liu J, Seo JH, Li Y, Chen D, Kurabayashi K, Fan X. Smart multi-channel two-dimensional micro-gas chromatography for rapid workplace hazardous volatile organic compounds measurement. LAB ON A CHIP 2013; 13:818-825. [PMID: 23303462 DOI: 10.1039/c2lc41159h] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We developed a novel smart multi-channel two-dimensional (2-D) micro-gas chromatography (μGC) architecture that shows promise to significantly improve 2-D μGC performance. In the smart μGC design, a non-destructive on-column gas detector and a flow routing system are installed between the first dimensional separation column and multiple second dimensional separation columns. The effluent from the first dimensional column is monitored in real-time and decision is then made to route the effluent to one of the second dimensional columns for further separation. As compared to the conventional 2-D μGC, the greatest benefit of the smart multi-channel 2-D μGC architecture is the enhanced separation capability of the second dimensional column and hence the overall 2-D GC performance. All the second dimensional columns are independent of each other, and their coating, length, flow rate and temperature can be customized for best separation results. In particular, there is no more constraint on the upper limit of the second dimensional column length and separation time in our architecture. Such flexibility is critical when long second dimensional separation is needed for optimal gas analysis. In addition, the smart μGC is advantageous in terms of elimination of the power intensive thermal modulator, higher peak amplitude enhancement, simplified 2-D chromatogram re-construction and potential scalability to higher dimensional separation. In this paper, we first constructed a complete smart 1 × 2 channel 2-D μGC system, along with an algorithm for automated control/operation of the system. We then characterized and optimized this μGC system, and finally employed it in two important applications that highlight its uniqueness and advantages, i.e., analysis of 31 workplace hazardous volatile organic compounds, and rapid detection and identification of target gas analytes from interference background.
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Affiliation(s)
- Jing Liu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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50
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Bugey A, Janin Y, Edder P, Bieri S. Targeted multidimensional gas chromatography using a heart-cutting device and cryogenic focusing for the determination of benzophenone derivatives in foodstuffs. Anal Bioanal Chem 2013; 405:4177-85. [PMID: 23423124 DOI: 10.1007/s00216-013-6808-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/21/2013] [Accepted: 01/29/2013] [Indexed: 10/27/2022]
Abstract
Photoinitiators are used to promote the polymerization process during the curing of varnishes or inks on cartonboard packaging. Depending on storage conditions and shelf life, these substances are able to migrate through the packaging layer into the foodstuff. This type of contamination phenomenon is therefore becoming a critical issue in terms of food safety. In order to tackle this problem, a fast and selective method was developed for the determination of benzophenone and three methylbenzophenone isomers in cereal-based foodstuffs and their cardboard packaging. Food samples or packages were efficiently extracted by pressurized liquid extraction using acetonitrile, and the extracts were directly injected onto the analytical system. The analysis was performed by multidimensional gas chromatography-mass spectrometry using a heart-cutting approach to reduce the background noise from complex matrices. The strategy employed two distinct cuts each containing its proper deuterated internal standard leading to accurate quantification. By integrating a cryofocusing effect, an enhancement in signal/noise ratio was achieved by a factor >10, which markedly decreased the sensitivity threshold. Moreover, baseline separation of the critical isomers allowed their unequivocal determination. The method was fully validated on cereal-based foodstuffs based upon an analysis of variance, and excellent performances were obtained at the decision limit making this method well suited for official food controls.
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Affiliation(s)
- Aurélie Bugey
- Swiss Centre for Applied Human Toxicology, University of Basel, Basel, Switzerland.
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