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Cain CN, Synovec RE. Enhancing gas chromatography-mass spectrometry resolution and pure analyte discovery using intra-chromatogram elution profile matching. Talanta 2024; 278:126453. [PMID: 38908137 DOI: 10.1016/j.talanta.2024.126453] [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: 04/17/2024] [Revised: 05/31/2024] [Accepted: 06/18/2024] [Indexed: 06/24/2024]
Abstract
Chemometric decomposition methods like multivariate curve resolution-alternating least squares (MCR-ALS) are often employed in gas chromatography-mass spectrometry (GC-MS) to improve analyte identification and quantitation. However, these methods can perform poorly for analytes with a low chromatographic resolution (Rs) and a high degree of spectral contamination from noise and background interferences. Thus, we propose a novel computational algorithm, termed mzCompare, to improve analyte identification and quantitation when coupled to MCR-ALS. The mzCompare method utilizes an underlying requirement that the retention time and peak shape between mass channels (m/z) of the same analyte should be similar. By discovering the selective m/z for a given analyte in a chromatogram, a pure elution profile can be generated and used as an equality constraint in MCR-ALS. The performance of the mzCompare methodology is demonstrated with both experimental and simulated chromatograms. Experimentally, unresolved analytes with a Rs as low as 0.05 could be confidently identified with mzCompare assisted MCR-ALS. Furthermore, application of the mzCompare algorithm to a complex aerospace fuel resulted in the discovery of 335 analytes, a 44 % increase compared to conventional peak detection methods. GC-MS simulations of target-interferent analyte pairs demonstrated that the performance of MCR-ALS deteriorated below a Rs of ∼0.25. However, mzCompare assisted MCR-ALS showed excellent identification and acceptable quantitative accuracy at a Rs of ∼0.02. These results show that the mzCompare algorithm can help analysts overcome modeling ambiguities resulting from the chemometric multiplex disadvantage.
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Affiliation(s)
- Caitlin N Cain
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA, 98195, USA
| | - Robert E Synovec
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA, 98195, USA.
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2
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Tikkisetty K, Filewood T, Yan J, Kwok H, Brunswick P, Cody R, Shang D. Method development for forensic oil identification by direct analysis in real time time-of-flight mass spectrometry. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:6040-6047. [PMID: 37916705 DOI: 10.1039/d3ay01282d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
The current well-established chromatography and mass spectrometry based oil spill identification procedures, such as those outlined by the European Committee for Standardization, are highly reliable as methods, highly defensible in the court of law, and widely applicable to the majority of oil spill situations. Nevertheless, the methodology is time consuming and labour intensive, which may not be ideal when dealing with an emergency oil spill situation. In this study, direct analysis in real time time-of-flight mass spectrometry (DART/TOFMS) was used to successfully develop an efficient oil identification method. To confirm the accuracy of this method spilled oil samples were tested from five previous years of blind round robin testing organized by the oil spill identification network of experts (OSINET) under the Bonn Agreement. Heatmap inspection, principal component analysis and finally discriminant analysis of principal components were used to arrive at final predictions regarding the identities of the spilled oil samples. The results were compared with the results of previous gas chromatography flame ionization detection (GC/FID) and gas chromatography triple quadrupole mass spectrometry (GC/MS/MS) analyses of the same oils. While taking only about a tenth of the time, the DART/TOFMS analysis produced results similar to those of classical GC/FID and GC/MS/MS (EI+) procedures. The ability of DART/TOFMS to display this level of validity exemplifies its potential to be a new tool for supplementing classical analyses for oil spill forensics.
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Affiliation(s)
- Krishnaja Tikkisetty
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Taylor Filewood
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Jeffrey Yan
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Honoria Kwok
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Pamela Brunswick
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | | | - Dayue Shang
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
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3
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de Carvalho CP, da Silva AJR, Lima RC, Eberlin MN. Mass spectrometry molecular fingerprinting of mineral and synthetic lubricant oils. JOURNAL OF MASS SPECTROMETRY : JMS 2023; 58:e4906. [PMID: 36916159 DOI: 10.1002/jms.4906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 01/17/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
The molecular composition of lubricating oils has a strong impact on how automotive engines function, but the techniques used to monitor the quality parameters of these oils only inspect their gross physical-chemical properties such as viscosity, color, and bulk spectroscopy profiles; hence, bad-quality, adulterated, or counterfeit oils are hard to detect. Herein, we investigated the ability of direct infusion electrospray ionization mass spectrometry (ESI-MS) to provide simple, rapid but characteristic fingerprint profiles for such oils of the mineral and synthetic types. After a simple aqueous extraction, ESI-MS analyses, particularly in the positive ion mode, did indeed show characteristic molecular markers with unique profiles, which were confirmed and more clearly visualized by partial least squares-discriminant analysis (PLS-DA). Nuclear magnetic resonance and Fourier transform infrared-attenuated total reflection spectroscopy were also tested for the bulk samples but showed nearly identical spectra, thus failing to reveal their distinct molecular composition and to differentiate the oil samples. To simulate adulteration, mixtures of mineral and synthetic oils were also analyzed by ESI(+)-MS, and additions as low as 1% of mineral oil to synthetic oil could be detected. The technique therefore offers a simple and fast but powerful tool to monitor the molecular composition of lubricant oils, particularly vias their more polar constituents.
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Affiliation(s)
- Caroline P de Carvalho
- MackMass Laboratory for Mass Spectrometry, School of Engineering, PPGEMN & Mackenzie Institute of Research in Graphene and Nanotechnologies, Mackenzie Presbyterian University, Rua da Consolação, 896, São Paulo, 01302-907, Brazil
| | - Adriano J R da Silva
- MackMass Laboratory for Mass Spectrometry, School of Engineering, PPGEMN & Mackenzie Institute of Research in Graphene and Nanotechnologies, Mackenzie Presbyterian University, Rua da Consolação, 896, São Paulo, 01302-907, Brazil
| | - Rosineide C Lima
- MackMass Laboratory for Mass Spectrometry, School of Engineering, PPGEMN & Mackenzie Institute of Research in Graphene and Nanotechnologies, Mackenzie Presbyterian University, Rua da Consolação, 896, São Paulo, 01302-907, Brazil
| | - Marcos N Eberlin
- MackMass Laboratory for Mass Spectrometry, School of Engineering, PPGEMN & Mackenzie Institute of Research in Graphene and Nanotechnologies, Mackenzie Presbyterian University, Rua da Consolação, 896, São Paulo, 01302-907, Brazil
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4
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Long chain fatty acids analysis of intertidal biofilm by direct injection liquid chromatography time of flight mass spectrometry. J Chromatogr A 2023; 1693:463870. [PMID: 36848732 DOI: 10.1016/j.chroma.2023.463870] [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: 01/05/2023] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/15/2023]
Abstract
The critical importance of mono- and polyunsaturated fatty acids (FAs) in a variety of biological functions, including animal nutrition and as an environmental stress monitor, is well recognized. However, while methods exist for monitoring of fatty acids, few are specific either to the profile of a microphytobenthos matrix or practical in application to multiple, diverse intertidal biofilm sample sets. In the current study, a sensitive liquid chromatography (LC) quadrupole time of flight mass spectrometry (QTOF) method was developed for the quantitative analysis of 31 FAs specific to intertidal biofilm, a thin mucilaginous layer of microalgae, bacteria, and other organisms on the surface of coastal mudflats, which provide a rich source of FAs for migratory birds. Preliminary screening of diverse biofilm samples collected from shorebird feeding grounds highlighted eight saturated (SFA), seven monounsaturated (MUFA), and sixteen polyunsaturated FAs (PUFA) that were selected for analysis. Improved method detection limits in the range 0.3-2.6 ngmL-1 were achieved, excepting for stearic acid at 10.6 ngmL-1. These excellent results were obtained without use of complex sample extraction and clean-up procedures undertaken by other published methods. An alkaline matrix of dilute aqueous ammonium hydroxide with methanol was shown to be selective for extraction and stability of the more hydrophilic fatty acid components. The direct injection method showed excellent precision and accuracy both during validation and application to hundreds of real-world intertidal biofilm samples from the Fraser River estuary (British Columbia, Canada) and other areas of the region frequented by shoreline birds.
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McCallum P, Filewood T, Sawitsky J, Kwok H, Brunswick P, Yan J, Chibwe L, Tikkisetty K, Shang D. Enhancement of oil forensic methodology through the addition of polycyclic aromatic nitrogen heterocycle biomarkers for diagnostic ratios. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:416. [PMID: 36807828 PMCID: PMC9941221 DOI: 10.1007/s10661-023-10941-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 01/12/2023] [Indexed: 06/18/2023]
Abstract
Current oil spill forensic identification of source oils relies upon hydrocarbon biomarkers resistant to weathering. This international technique was developed by the European Committee for Standardization (CEN), under EN 15522-2 Oil Spill Identification guidelines. The number of biomarkers have expanded at pace with technological advances, while distinguishing new biomarkers becomes more challenging due to interference of isobaric compounds, matrix effects, and high cost of weathering experiments. Application of high-resolution mass spectrometry enabled exploration of potential polycyclic aromatic nitrogen heterocycle (PANH) oil biomarkers. The instrumentation showed reduction in isobaric and matrix interferences, allowing for identification of low-level PANH and alkylated PANHs (APANHs). Weathered oil samples, obtained from a marine microcosm weathering experiment, enabled comparison with source oils to identify new, stable forensic biomarkers. This study highlighted eight new APANH diagnostic ratios that expanded the biomarker suite, increasing the confidence for identifying highly weathered oils back to their source oil.
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Affiliation(s)
- Paige McCallum
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Taylor Filewood
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Julia Sawitsky
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Honoria Kwok
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Pamela Brunswick
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada.
| | - Jeffrey Yan
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Leah Chibwe
- Institute for Environmental Change and Society, University of Regina, SK, Regina, Canada
| | - Krishnaja Tikkisetty
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada
| | - Dayue Shang
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, B.C, Canada.
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Lee D, Seo JM, Kooistra K, Lee H. Identification of bilge oil with lubricant: Recent oil spill case studies. ENVIRONMENTAL RESEARCH 2022; 212:113325. [PMID: 35439455 DOI: 10.1016/j.envres.2022.113325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/10/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Oil spills have many adverse effects on the marine environment. Bilge oil spills occur frequently in the sea as a result of maritime accidents or illegal discharge. It is difficult to unambiguously identify the specific sources of such spills because bilge oil contains a mixture of fuel oil and lubricant. In this study, bilge oils with different fuel oil/lubricant ratios were prepared and analyzed using a modified version of the CEN/TR methodology (European Committee for Standardization, 2012). As the lubricant content of bilge oil increased, the intensity of the C20-C24 group, which is the commonly-used normalization compound group for fuel oil in the percentage weathering (PW) plot, also changed. Therefore, the mean area of the C15-C18 group, which was affected by the lubricant content, was used instead. Although heavy fuel oil is usually normalized to a hopane, bilge oil with a high lubricant content cannot be analyzed based on a mass spectrometry (MS)-PW plot; thus, heavy fuel oil-based bilge oil was normalized to a phytane in this study. Although hopanes and styrenes are unsuitable comparison compounds for heavy fuel oil-based bilge oil analysis, for light fuel oil-based bilge oil, hopanes and steranes could be applied as diagnostic ratio comparisons when the lubricant peak was clearly detected in the chromatograms of the spilled and suspected oil samples. By applying the CEN/TR methodology according to this approach, the similarities between spilled and suspected oil samples were more easily revealed. In addition, the field applicability of the proposed method was tested for four actual oil spills.
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Affiliation(s)
- Duwon Lee
- Korea Coast Guard Research Center, Korea Coast Guard Academy, Korea Coast Guard, Cheonan, 31254, South Korea
| | - Jeong Mog Seo
- Korea Coast Guard Research Center, Korea Coast Guard Academy, Korea Coast Guard, Cheonan, 31254, South Korea
| | - Kees Kooistra
- Rijkswaterstaat Laboratory, Ministry of Infrastructure and Water Management, Lelystad, 8224, the Netherlands
| | - Heejin Lee
- Korea Coast Guard Research Center, Korea Coast Guard Academy, Korea Coast Guard, Cheonan, 31254, South Korea.
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Filewood T, Kwok H, Brunswick P, Yan J, Ollinik JE, Cote C, Kim M, van Aggelen G, Helbing CC, Shang D. Advancement in oil forensics through the addition of polycyclic aromatic sulfur heterocycles as biomarkers in diagnostic ratios. JOURNAL OF HAZARDOUS MATERIALS 2022; 435:129027. [PMID: 35525008 DOI: 10.1016/j.jhazmat.2022.129027] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 04/18/2022] [Accepted: 04/25/2022] [Indexed: 06/14/2023]
Abstract
In current oil spill forensics, diagnostic ratios of hydrocarbon biomarker responses are commonly used to compare oil spill samples to source materials in order to determine the identity of the oil. This well recognized procedure was developed by the European Committee for Standardization (CEN) with corresponding published EN 15522-2 Oil Spill Identification guidelines. However, it is further recognized that weathering can have a negative effect on some of the biomarkers used in the analysis, leading to decreased confidence in the result. In this study, polycyclic aromatic sulfur heterocycles (PASHs) and their alkylated forms (APASHs) were assessed for their potential as additional biomarkers. With the aim of identifying stable PASHs and APASHs useful as weathered oil biomarkers, the superior specificity of gas chromatography with high resolution mass spectrometry was exploited to determine chromatographic peak responses for sixteen petroleum oil samples. Extensive study, involving microcosm extreme weathering and spreadsheet development, led to the identification of 19 new diagnostic ratios based on newly discovered stable PASH and APASH biomarkers. Application of the extended diagnostic ratio suite showed high potential to improve the forensic attribution of post-spill weathered oil back to its original source.
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Affiliation(s)
- Taylor Filewood
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Honoria Kwok
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Pamela Brunswick
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada.
| | - Jeffrey Yan
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Jessica E Ollinik
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Christopher Cote
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Marcus Kim
- Agilent Technologies Inc., Mississauga, ON, Canada
| | - Graham van Aggelen
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada
| | - Caren C Helbing
- Department of Biochemistry & Microbiology and Centre for Biomedical Research, University of Victoria, BC, Canada
| | - Dayue Shang
- Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, Pacific and Yukon Laboratory for Environmental Testing, North Vancouver, BC, Canada.
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8
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Filewood T, Kwok H, Brunswick P, Yan J, Ollinik JE, Cote C, Kim M, van Aggelen G, Helbing CC, Shang D. A rapid gas chromatography quadrupole time-of-flight mass spectrometry method for the determination of polycyclic aromatic hydrocarbons and sulfur heterocycles in spilled crude oils. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2022; 14:717-725. [PMID: 35107097 DOI: 10.1039/d1ay02216d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Spilled crude oil samples contain various toxic compounds including polycyclic aromatic hydrocarbons (PAHs) as well as sulfur heterocycles (PASHs) and their related alkylated forms (APAHs and APASHs). In this study, a method was successfully developed employing a gas chromatography quadrupole time-of-flight (GC-QToF) mass spectrometer to quantitatively analyze both PAHs/APAHs and PASHs/APASHs in these samples. With GC-QToF, the monoisotopic mass of the compounds is distinguished, allowing the PASHs/APASHs to be extracted separately from the PAHs/APAHs in crude oil. A gas chromatography triple quadrupole (GC-MS/MS) mass spectrometer was also used to confirm that a GC-QToF is the preferred instrument for analyzing these compounds. With the use of PASH/APASH standards to determine response correction factors (RCFs) in relation to PAH standards, the developed method is capable of analyzing PAHs, APAHs, PASHs, and APASHs in a single injection. The use of RCFs allowed for the development of a practical polycyclic aromatic carbon (PAC) method for analyzing a total of 77 compounds of the 2 groups in crude oil. This newly developed method was applied to spilled crude oils, demonstrating its potential in toxicological study as well as oil spill forensic investigation.
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Affiliation(s)
- Taylor Filewood
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Honoria Kwok
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Pamela Brunswick
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Jeffrey Yan
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Jessica E Ollinik
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Christopher Cote
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Marcus Kim
- Agilent Technologies Inc., Mississauga, Ontario, Canada
| | - Graham van Aggelen
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
| | - Caren C Helbing
- Department of Biochemistry & Microbiology and Centre for Biomedical Research, University of Victoria, British Columbia, Canada
| | - Dayue Shang
- Pacific and Yukon Laboratory for Environmental Testing, Science and Technology Branch, Pacific Environmental Science Centre, Environment and Climate Change Canada, North Vancouver, British Columbia, Canada.
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Chua CC, Brunswick P, Kwok H, Yan J, Cuthbertson D, van Aggelen G, Helbing CC, Shang D. Enhanced analysis of weathered crude oils by gas chromatography-flame ionization detection, gas chromatography-mass spectrometry diagnostic ratios, and multivariate statistics. J Chromatogr A 2020; 1634:461689. [DOI: 10.1016/j.chroma.2020.461689] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 10/23/2022]
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