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Mullin, Lauren Gayle
Publications (10 of 11) Show all publications
Mullin, L. G. (2019). Advances in Mass Spectrometry for the Analysis of Emerging Persistent Organic Pollutants. (Doctoral dissertation). Örebro: Örebro University
Open this publication in new window or tab >>Advances in Mass Spectrometry for the Analysis of Emerging Persistent Organic Pollutants
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Mass spectrometry (MS) is a technique widely implemented for the measurement of environmental pollutants. A critical tool for the analysis of persistent organic pollutants (POPs) over several decades, MS as coupled with liquid and gas chromatography (LC and GC) techniques enables the analysis of emerging POPs. The aim of this thesis was to investigate the use of alternative MS-based techniques to assist specific analytical challenges including separation of stereoisomers using supercritical fluid chromatography (SFC), reduced ionization competition with appropriate mobile phase additives, and applied rotationally averaged collision-cross section (CCS) of ions via ion mobility measurements of emerging POPs.

Chromatographic efficiency improvements for the brominated flame retardant, hexabromocyclododecane (HBCDD), were implemented through the development of two supercritical fluid chromatography (SFC) methods. Based on the inherent qualities of supercritical fluids, separation of both predominant diastereomers and respective enantiomers was performed in a shorter time with wider chromatographic resolution using SFC than existing LC methods.

Turning next to MS ionization considerations, the emerging perfluoroalkyl substance hexafluoropropylene oxide-dimer acid (HFPO-DA) was investigated. Following a survey of analytical methodologies for HFPO-DA, the challenge of extreme dimer formation, in-source fragmentation and very low [M-H]- production was described. Method development using alternative mobile phase additives in currently used LC-MS acquisition techniques was deployed.

Finally, ion mobility spectrometry (IMS) was implemented in a non-targeted acquisition study of indoor dust samples. This study used IMS coupled with quadrupole time-of-flight MS to identify a wide range of contaminant classes, including emerging POPs. Identification confidence is a challenge currently facing non-targeted studies, and the use of prediction mechanisms of analyte IMS gas-phase separations was explored.

Through applying diverse alternative techniques, increased method performance was explored for emerging POPs analyses.

Place, publisher, year, edition, pages
Örebro: Örebro University, 2019. p. 83
Series
Örebro Studies in Chemistry, ISSN 1651-4270 ; 24
Keywords
Mass Spectrometry, Liquid Chromatography, Supercritical Fluid Chromatography, Ion Mobility, POPs, Electrospray Ionization
National Category
Other Chemistry Topics
Identifiers
urn:nbn:se:oru:diva-76213 (URN)978-91-7529-303-5 (ISBN)
Public defence
2019-10-25, Örebro universitet, Hörsalen, Musikhögskolan, Fakultetsgatan 1, Örebro, 09:15 (English)
Opponent
Supervisors
Available from: 2019-09-11 Created: 2019-09-11 Last updated: 2019-10-02Bibliographically approved
Mullin, L. G., Katz, D. R., Riddell, N., Plumb, R., Burgess, J. A., Yeung, L. W. Y. & Ericson Jogsten, I. (2019). Analysis of hexafluoropropylene oxide-dimer acid (HFPO-DA) by liquid chromatography-mass spectrometry (LC-MS): Review of current approaches and environmental levels. TrAC. Trends in analytical chemistry, 118, 828-839
Open this publication in new window or tab >>Analysis of hexafluoropropylene oxide-dimer acid (HFPO-DA) by liquid chromatography-mass spectrometry (LC-MS): Review of current approaches and environmental levels
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2019 (English)In: TrAC. Trends in analytical chemistry, ISSN 0165-9936, E-ISSN 1879-3142, Vol. 118, p. 828-839Article, review/survey (Refereed) Published
Abstract [en]

Emerging per- and polyfluorinated compounds (PFAS) compounds are of increasing interest for environmental monitoring, one being hexafluoropropylene oxide-dimer acid (HFPO-DA), commonly referred to as GenX. The following review describes existing liquid chromatography-mass spectrometry (LC-MS) methods used to analyse HFPO-DA, including sample preparation and method sensitivity relative to other PFAS. Analytical challenges are also described, in particular the significant formation of in-source fragmentation, dimer and dimer adducts which detract from [M-H](-) signal. Lastly, detected levels of HFPO-DA in environmental and biological samples are compared across the limited number of available field exposure studies, which found several mu g/L concentrations in water samples taken near fluorochemical plant discharges.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
HFPO-DA, GenX, Negative polarity electrospray ionisation, Liquid chromatography, Mass spectrometry
National Category
Chemical Sciences
Identifiers
urn:nbn:se:oru:diva-76970 (URN)10.1016/j.trac.2019.05.015 (DOI)000486383900064 ()31501636 (PubMedID)
Note

Funding Agency:

Intramural EPA  EPA999999

Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-10-02Bibliographically approved
Mullin, L. G. & Plumb, R. (2018). Characterization of metabolic variability in red wines using a highly selective non-targeted acquisition approach. Paper presented at 255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, New Orleans, LA, USA, March 18-22, 2018. Abstract of Papers of the American Chemical Society, 255
Open this publication in new window or tab >>Characterization of metabolic variability in red wines using a highly selective non-targeted acquisition approach
2018 (English)In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2018
National Category
Other Chemistry Topics
Identifiers
urn:nbn:se:oru:diva-68091 (URN)000435537700280 ()
Conference
255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, New Orleans, LA, USA, March 18-22, 2018
Available from: 2018-07-24 Created: 2018-07-24 Last updated: 2018-07-24Bibliographically approved
Mullin, L. G., Ladak, A., Cleland, G. & Ericson Jogsten, I. (2016). Biomonitoring of GC and LC amenable environmental contaminants using a single MS platform. Paper presented at 36th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2016, Florence, Italy, August 28 - September 2, 2016. Organohalogen Compounds, 78
Open this publication in new window or tab >>Biomonitoring of GC and LC amenable environmental contaminants using a single MS platform
2016 (English)In: Organohalogen Compounds, ISSN 1026-4892, Vol. 78Article in journal (Refereed) Published
Abstract [en]

Monitoring of environmental contaminants in biological samples is typically performed by targeted analysis using a tandem quadrupole system on separate GC and LC platforms in order to cover the expansive range of compounds. Use of multiple systems can add complexity to the analysis and increase turnaround times for samples to be reported. The work that will be presented will show the analysis of common environmental contaminants in a biomonitoring context on a single high resolution mass spectrometric (HRMS) platform. The compounds of interest include:

  • GC amenable compounds: Halogenated pesticides, BFRs, PCBs and PCDD/Fs
  • LC amenable compounds: Perfluoroalkyl substances, HBCDD/TBBP-A and phosphorus-based flame retardants
Place, publisher, year, edition, pages
Eco-Informa Press, 2016
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-65616 (URN)
Conference
36th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2016, Florence, Italy, August 28 - September 2, 2016
Available from: 2018-03-09 Created: 2018-03-09 Last updated: 2018-04-05Bibliographically approved
Riddell, N., Mullin, L. G., van Bavel, B., Ericson Jogsten, I., McAlees, A., Brazeau, A., . . . Chittim, B. (2016). Enantioselective Analytical- and Preparative-Scale Separation of Hexabromocyclododecane Stereoisomers Using Packed Column Supercritical Fluid Chromatography. Molecules, 21(11), Article ID 1509.
Open this publication in new window or tab >>Enantioselective Analytical- and Preparative-Scale Separation of Hexabromocyclododecane Stereoisomers Using Packed Column Supercritical Fluid Chromatography
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2016 (English)In: Molecules, ISSN 1420-3049, E-ISSN 1420-3049, Vol. 21, no 11, article id 1509Article in journal (Refereed) Published
Abstract [en]

Hexabromocyclododecane (HBCDD) is an additive brominated flame retardant which has been listed in Annex A of the Stockholm Convention for elimination of production and use. It has been reported to persist in the environment and has the potential for enantiomer-specific degradation, accumulation, or both, making enantioselective analyses increasingly important. The six main stereoisomers of technical HBCDD (i.e., the (+) and (-) enantiomers of α-, β-, and γ-HBCDD) were separated and isolated for the first time using enantioselective packed column supercritical fluid chromatography (pSFC) separation methods on a preparative scale. Characterization was completed using published chiral liquid chromatography (LC) methods and elution profiles, as well as X-ray crystallography, and the isolated fractions were definitively identified. Additionally, the resolution of the enantiomers, along with two minor components of the technical product (δ- and ε-HBCDD), was investigated on an analytical scale using both LC and pSFC separation techniques, and changes in elution order were highlighted. Baseline separation of all HBCDD enantiomers was achieved by pSFC on an analytical scale using a cellulose-based column. The described method emphasizes the potential associated with pSFC as a green method of isolating and analyzing environmental contaminants of concern.

Place, publisher, year, edition, pages
Basel, Switzerland: MDPI AG, 2016
Keywords
hexabromocyclododecane, enantiomeric separation, supercritical fluid chromatography
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-53487 (URN)10.3390/molecules21111509 (DOI)000389918200091 ()27834934 (PubMedID)2-s2.0-84997428723 (Scopus ID)
Available from: 2016-11-15 Created: 2016-11-14 Last updated: 2019-10-02Bibliographically approved
Mullin, L., Burgess, J. A., Jogsten, I. E., Geng, D., Aubin, A. & van Bavel, B. (2015). Rapid separation of hexabromocyclododecane diastereomers using a novel method combining convergence chromatography and tandem mass spectrometry. Analytical Methods, 7(7), 2950-2958
Open this publication in new window or tab >>Rapid separation of hexabromocyclododecane diastereomers using a novel method combining convergence chromatography and tandem mass spectrometry
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2015 (English)In: Analytical Methods, ISSN 1759-9660, E-ISSN 1759-9679, Vol. 7, no 7, p. 2950-2958Article in journal (Refereed) Published
Abstract [en]

Analysis of the brominated flame retardant hexabromocyclododecane (HBCDD) is characterized by the separation of its three predominant diastereomers. This analysis is typically performed using reversed phase liquid chromatography (RPLC) coupled with mass spectrometric (MS) detection with analysis times in the order of 10 minutes or greater. Here we describe a rapid method using supercritical CO2 and methanol to baseline separate the three most abundant HBCDD diastereomers within a three minute run time using a High Strength Silica (HSS) C18 1.8 mu m particle size column. A unique elution order of the alpha-, beta- and gamma-HBCDD diastereomers using supercritical CO2 was observed, and can be used as an orthogonal separation for further confidence in diastereomer identification when used in conjuction with RPLC. A tandem quadrupole mass spectrometer with negative mode electrospray ionization was used for detection, operating in multiple reaction monitoring (MRM) mode. Ionization was enhanced by the addition of a make-up flow, which was introduced to the post-column effluent. Method limit of detection (LOD) and limit of quantification (LOQ) for alpha-, beta- and gamma-HBCDD were based on peak-to-peak signal to noise ratios of greater than 3 or 10, respectively. The LOD for all HBCDD diastereomers as solvent standards was 100 fg on-column, and LOQs 500 fg on-column for alpha- and gamma-HBCDD and 250 fg on-column for beta-HBCDD. In order to test the efficiency of this method, small subsets of complex human serum and whale blubber extracts were analyzed using this method, resulting in positive detections in samples of alpha-HBCDD.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2015
National Category
Analytical Chemistry
Research subject
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-44434 (URN)10.1039/c4ay02923b (DOI)000351931000008 ()
Available from: 2015-04-24 Created: 2015-04-24 Last updated: 2019-10-09Bibliographically approved
Mullin, L. G., Ladak, A., Ericson Jogsten, I., Stevens, D., Graham, K., Burgess, J., . . . van Bavel, B. (2014). Detection of persistent organic pollutants using atmospheric pressure gas chromatography and a novel acquisition mode for quadrupole time-of-flight MS. Paper presented at 34th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2014, Madrid, Spain, August 31 - September 5, 2014. Organohalogen Compounds, 76
Open this publication in new window or tab >>Detection of persistent organic pollutants using atmospheric pressure gas chromatography and a novel acquisition mode for quadrupole time-of-flight MS
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2014 (English)In: Organohalogen Compounds, ISSN 1026-4892, Vol. 76Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Eco-Informa Press, 2014
National Category
Analytical Chemistry
Research subject
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-65493 (URN)
Conference
34th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2014, Madrid, Spain, August 31 - September 5, 2014
Available from: 2018-03-05 Created: 2018-03-05 Last updated: 2018-04-05Bibliographically approved
Ericson Jogsten, I., Mullin, L. G., Dillon, L., Burgess, J. & McCullagh, M. (2014). The implementation of a screening workflow for the ion mobility quadrupole time-of-flight mass spectrometric analysis of PFOS isomers. Paper presented at 34th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2014, Madrid, Spain, August 31 - September 5, 2014. Organohalogen Compounds, 76
Open this publication in new window or tab >>The implementation of a screening workflow for the ion mobility quadrupole time-of-flight mass spectrometric analysis of PFOS isomers
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2014 (English)In: Organohalogen Compounds, ISSN 1026-4892, Vol. 76Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Eco-Informa Press, 2014
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-65496 (URN)
Conference
34th International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2014, Madrid, Spain, August 31 - September 5, 2014
Available from: 2018-03-05 Created: 2018-03-05 Last updated: 2018-04-05Bibliographically approved
Mullin, L. G., van Bavel, B., Burgess, J., Aubin, A., Ericson Jogsten, I. & Geng, D. (2013). Rapid separation of hexabromocyclododecane diastereomers and tetrabromobisphenol-A using a novel method combining convergence chromatography and MS/MS detection. Paper presented at 33rd International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2013, Inter Burgo Daegu, Korea, August 25-30, 2013. Organohalogen Compounds, 75
Open this publication in new window or tab >>Rapid separation of hexabromocyclododecane diastereomers and tetrabromobisphenol-A using a novel method combining convergence chromatography and MS/MS detection
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2013 (English)In: Organohalogen Compounds, ISSN 1026-4892, Vol. 75Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Eco-Informa Press, 2013
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:oru:diva-65498 (URN)
Conference
33rd International Symposium on Halogenated Persistent Organic Pollutants, Dioxin 2013, Inter Burgo Daegu, Korea, August 25-30, 2013
Available from: 2018-03-05 Created: 2018-03-05 Last updated: 2018-04-05Bibliographically approved
Mullin, L. G., Riddell, N., Plumb, R. S., Burgess, J. A., Ericson Jogsten, I. & Yeung, L. W. Y.Ionization Enhancement of Hexafluoropropylene oxide dimer acid (HFPO-DA) Through Mobile Phase Additive Selection.
Open this publication in new window or tab >>Ionization Enhancement of Hexafluoropropylene oxide dimer acid (HFPO-DA) Through Mobile Phase Additive Selection
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(English)Manuscript (preprint) (Other academic)
National Category
Other Chemistry Topics
Identifiers
urn:nbn:se:oru:diva-76979 (URN)
Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-10-02Bibliographically approved
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