Abstract:

Blood serum of bottlenose dolphins (Tursiops truncatus) collected from Barataria Bay, Louisiana following the Deepwater Horizon oil spill from 2011-08-04 to 2018-07-19 were analyzed for lipid content by Ultra-High Pressure Liquid Chromatography-High Resolution Tandem Gas Mass Spectrometry (UHPLC/HRMS/MS).

Suggested Citation:

Napolitano, Michael P. and Maggie Broadwater. 2020. Nontargeted Lipidomics by Ultra-High Pressure Liquid Chromatography-High Resolution Tandem Gas Mass Spectrometry (UHPLC/HRMS/MS) for Blood Serum of the Bottlenose Dolphin from Barataria Bay, Louisiana following the Deepwater Horizon Oil Spill, 2011-08-04 to 2018-07-19. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-hb8a-r002

Purpose:

In April 2010, the oil drilling platform Deepwater Horizon (DWH) in the northern Gulf of Mexico exploded, which led to a massive oil spill affecting many ecosystems and species, including the bottlenose dolphin (Tursiops truncatus) of Barataria Bay, Louisiana. Dolphins suffered many direct toxic effects of oil exposure and this project sought to determine if any of those effects were observable in their lipid content from blood serum across six sampling years.

Data Parameters and Units:

Worksheet Column.header Description All.identified.features Unique.ID Unique identifier for lipidomics features All.identified.features Row.ID Unique row number for each lipid within each polarity. Missing row numbers occur due to deleted features that were duplicate or pruned after improper normalization to internal standard. All.identified.features Polarity Indicates charge of the lipid's ion during instrumental detection. All.identified.features IS.Quantified Indicates if that feature was normalized to an internal standard. (1 = true) All.identified.features IS.Species Indicates to which internal standard that feature was normalized. All.identified.features IS.Adduct Indicates which ionic form of the internal standard was used to normalize that feature. All.identified.features Row.mz Mass to charge ratio of the detected ion of that feature. All.identified.features Row.retention.time Chromatographic retention time of the detected ion of that feature. (min) All.identified.features Row.n.of.detected.peaks Lipid identification software's (LipidMatch) internal notation; not significant for end user. All.identified.features Class.at.max.intensity Abbreviation of lipid class with highest spectral intensity among possible lipid identifications for that feature. All.identified.features Adduct.at.max.intensity Ionic form of lipid with highest spectral intensity among possible lipid identification for that feature. All.identified.features Only.one.class Determination if one or more class(es) of lipid was(were) identified for that feature other than the class at max intensity. All.identified.features ISTD User-generated column to identify features that were added as part of the internal standard mix. All.identified.features Molecular Molecular name of the lipid at that feature, abbreviated class and with no ion All.identified.features Adducts.confirmed.by.MS.MS Superfluous column added by lipid identification software (LipidMatch). All.identified.features ID.ranked All potential lipids identified for that feature and ranked (i.e., 1, 2, 3, 4, 5) by their certainty (1 is highest). All.identified.features Intensity.ranked Sum of mass spectral intensities of lipid fragment ions for each potential lipid identified in "ID.ranked" column. (arbitrary units) All.identified.features All.identity.elements Superfluous column added by lipid identification software (LipidMatch). All.identified.features Peak.area_SRM1950_1 Chromatographic peak area of feature for quality control sample "SRM1950_1". (arbitrary units) All.identified.features Peak.area_SRM1950_2 Chromatographic peak area of feature for quality control sample "SRM1950_2". (arbitrary units) All.identified.features Peak.area_SRM1950_3 Chromatographic peak area of feature for quality control sample "SRM1950_3". (arbitrary units) All.identified.features Peak.area_SRM1950_4 Chromatographic peak area of feature for quality control sample "SRM1950_4". (arbitrary units) All.identified.features Peak.area_SRM1950_5 Chromatographic peak area of feature for quality control sample "SRM1950_5". (arbitrary units) All.identified.features Peak.area_SRM1950_6 Chromatographic peak area of feature for quality control sample "SRM1950_6". (arbitrary units) All.identified.features Peak.area_SRM1950_7 Chromatographic peak area of feature for quality control sample "SRM1950_7". (arbitrary units) All.identified.features Peak.area_SRM1950_8 Chromatographic peak area of feature for quality control sample "SRM1950_8". (arbitrary units) All.identified.features Peak.area_SRM1950_9 Chromatographic peak area of feature for quality control sample "SRM1950_9". (arbitrary units) All.identified.features Peak.area_Pool_YYYY Raw area under the chromatographic peak (arbitrary units) for the identified feature for the pooled samples collected in a given year (YYYY) All.identified.features Peak.area_XXX_YYYY Raw area under the chromatographic peak (arbitrary units) for the identified feature for the sample from dolphin XXX, sampled in year YYYY Normalized.SOI.by.sample Unique.ID Unique identifier for lipidomics features; same feature as "All.identified.features" tab. Normalized.SOI.by.sample Row.ID Unique row number for each lipid within each polarity. Missing row numbers occur due to deleted features that were unable to be normalized. Normalized.SOI.by.sample Polarity Indicates charge of the lipid's ion during instrumental detection. Normalized.SOI.by.sample IS.Quantified Indicates if that feature was normalized to an internal standard. (1 = true) Normalized.SOI.by.sample IS.Species Indicates to which internal standard that feature was normalized. Normalized.SOI.by.sample IS.Adduct Indicated to which ionic form of the internal standard that feature was normalized. Normalized.SOI.by.sample Row.mz Mass to charge ratio of the detected ion of that feature. Normalized.SOI.by.sample Row.retention.time Chromatographic retention time of the detected ion of that feature. (min) Normalized.SOI.by.sample Row.n.of.detected.peaks Lipid identification software's (LipidMatch) internal notation; not significant for end user. Normalized.SOI.by.sample Class.at.max.intensity Abbreviation of lipid class with highest spectral intensity among possible lipid identifications for that feature. Normalized.SOI.by.sample Adduct.at.max.intensity Ionic form of lipid with highest spectral intensity among possible lipid identification for that feature. Normalized.SOI.by.sample Only.one.class Determination if one or more class(es) of lipid was(were) identified for that feature other than the class at max intensity. Normalized.SOI.by.sample ISTD User-generated column to identify features that were added as part of the internal standard mix. Normalized.SOI.by.sample Molecular Molecular name of the lipid at that feature, abbreviated class and with no ion Normalized.SOI.by.sample Adducts.confirmed.by.MS.MS Superfluous column added by lipid identification software (LipidMatch). Normalized.SOI.by.sample ID.ranked All potential lipids identified for that feature and ranked (i.e., 1, 2, 3, 4, 5) by their certainty (1 is highest). Normalized.SOI.by.sample Intensity.ranked Sum of mass spectral intensities of lipid fragment ions for each potential lipid identified in "ID.ranked" column. (arbitrary units) Normalized.SOI.by.sample All.identity.elements Superfluous column added by lipid identification software (LipidMatch). Normalized.SOI.by.sample Norm.peak.area_SRM1950_1 Normalized concentration of feature for quality control sample "SRM1950_1". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_2 Normalized concentration of feature for quality control sample "SRM1950_2". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_3 Normalized concentration of feature for quality control sample "SRM1950_3". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_4 Normalized concentration of feature for quality control sample "SRM1950_4". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_5 Normalized concentration of feature for quality control sample "SRM1950_5". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_6 Normalized concentration of feature for quality control sample "SRM1950_6". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_7 Normalized concentration of feature for quality control sample "SRM1950_7". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_8 Normalized concentration of feature for quality control sample "SRM1950_8". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_SRM1950_9 Normalized concentration of feature for quality control sample "SRM1950_9". (nmol/L) Normalized.SOI.by.sample Norm.peak.area_Pool_YYYY Normalized concentration (nmol/mL) of the identified feature for the pooled samples collected in a given year (YYYY) Normalized.SOI.by.sample Norm.peak.area_XXX_YYYY Normalized concentration (nmol/mL) of the identified feature for the sample from dolphin XXX, sampled in year YYYY Sample.description Sample.source Unique identifier for the dolphin from which the sample was collected, or an identifier for laboratory control samples Sample.description Sample.collection.date Date sample was collected in the field (m/d/y) Sample.description Latitude Latitude at which sample was collected in the field (decimal degrees) Sample.description Longitude Longitude at which sample was collected in the field (decimal degrees)

Methods:

Dolphin blood was collected during capture-release and stored at −80 °C. After thawing, 50-µL of serum was spiked with an internal standard (ISTD) lipid cocktail. Lipids were extracted, dried, and reconstituted with 1-mL isopropanol. Samples were analyzed with a 22-min UHPLC separation using a gradient and high-resolution mass spectrometry, for both polarities. Full-scan spectra were recorded followed by the collection of product-ion spectra in a top-10 data-dependent method employing semi-automated iterative exclusion for three successive injections. Feature lists were created from binning full-scans with mzXML, identifications were obtained with LipidMatch and then normalized to ISTD.

Individual Files: