Analytical services in ecology
Fatty acid analysis specializing in aquatic organisms
The Pelagic Ecosystems Lab at the University of British Columbia specializes in the analytical determination of fatty acids in samples from aquatic environments, with extensive experience analyzing phytoplankton, zooplankton, fish, and shellfish. We offer fee-for-service fatty acid analyses, as well as sample preparation services and total lipid content analyses. Fatty acid data provided includes quantities of 48 fatty acids commonly found in aquatic organisms. Please contact us before sending samples. Minimum number of samples per batch is 40. If you are interested in fewer analyses, please contact us: a.mclaskey@oceans.ubc.ca
Services provided and price list
Prices are in Canadian dollars. Costs are per sample, unless otherwise stated. Prices do not include any applicable local and federal taxes.
Samples that are less than 10 mg dry weight, or phytoplankton that will be analyzed on GF/F filters, require additional materials for sample concentration.
Sample Submission
Samples can be received frozen wet on dry ice or already freeze dried, and may require further sample preparation, offered at an additional fee. Please see descriptions for each analysis type to determine whether sample preparation will be required.
Please note that sample containers (vials, tubes, bags, etc.) will not be returned after analysis, unless explicitly requested by the submitter. Excess raw sample material can be returned upon request at the submitter’s expense.
Before sample submission please complete the electronic sample list (PEL Sample Submission Form) and email this to us.
Submitting Samples for Fatty Acid Analysis
Samples for fatty acid analysis should be stored frozen at -80 °C (or less than 1 month at -20 °C) from collection until analysis. Ideally, samples should be transported to us on dry ice or by dry shipper.
Samples for fatty acid analysis must contain less than 10 mg lipid. Wet and dry weight estimates for this upper lipid threshold are provided in the table below. Samples that exceed this lipid content must be homogenized and sub-sampled before analysis. Large samples can be homogenized after freeze drying for an additional fee.
Samples with less than 2 mg lipid (see estimates for different sample types below) can be analyzed with an additional fee charged for the extra materials required. Samples can also be analyzed on GF/F filters that were combusted (4 h at 450 °C) prior to sampling, with an additional fee for the extra materials required.
To help determine whether sample processing will be required or an additional fee for extra materials required will be charged, please use this decision flow chart:
Submitting samples for Total Lipid analysis
If requested, total lipid content can be analyzed on the same samples analyzed for fatty acids without submitting additional sample material.
If only total lipid analysis is required, 100 mg of dry homogenized tissue is routinely analyzed (smaller quantities are possible if discussed). Samples for only total lipid content can be oven dried (50 °C) rather than freeze dried.
Samples for total lipid content can be received dry at room temperature or frozen wet. Samples requiring homogenization will be charged an additional fee.
Submitting samples for Sample Preparation
Samples requiring homogenization before analysis can be submitted for sample preparation. Each sample to be analyzed must be packaged individually, i.e., the contents of one container will be homogenized together.
Excess raw sample material can be returned upon request at the submitter’s expense.
Methods
Sample preparation: samples are weighed wet, freeze dried 24 h or until dry, weighed dry, and homogenized by hand with mortar and pestle.
Total lipid content: This extraction is a modified Folch technique using chloroform:methanol:water. It is efficiently used to extract the labile lipids from a variety of marine samples such as phytoplankton, zooplankton, shellfish, and fish tissues.
Fatty acid analysis: Fatty acids are quantified by gas chromatography with flame ionization detector (GC-FID, Scion-436). Fatty acids are extracted and converted to fatty acid methyl esters (FAMEs) using a direct transesterification method with HCl as a catalyst (detailed in McLaskey et al. 2022). FAMEs are then separated using an Agilent DB-23 column (30m, 0.25 mm, 0.15 μm) and identified by comparing to commercially available standards (GLC 37, Nu-Chek Prep, Inc; PUFA-3 Mixture, Sigma-Aldrich; Bacterial Acid Methyl Esters CP Mixture, Matreya LLC) and laboratory reference materials that have been validated by GC-MS. Fatty acids are quantified by the addition of an internal standard, C19:0.
Fatty acids routinely identified
Publications
A selection of works that have benefitted from the PEL fatty acid facility
McLaskey AK, Forster I, Hunt BPV (2024) Distinct trophic ecologies of zooplankton size classes are maintained throughout the seasonal cycle. Oecologia. https://doi.org/10.1007/s00442-023-05501-y
Schaub J, McLaskey AK, Forster I, Hunt BPV(2023) Size-based changes in trophic ecology and nutritional quality of moon jellyfish (Aurelia labiata). Ecosphere 14 (3), https://doi.org/10.1002/ecs2.4430
McLaskey AK, Forster I, Del Bel Belluz J, Hunt BPV (2022) A high-resolution time series of particulate matter fatty acids reveals temporal dynamics of the composition and quality available to zooplankton in a temperate coastal ocean. Progress in Oceanography 206, https://doi.org/10.1016/j.pocean.2022.102843;McLaskey et al. 2022
Schaub J, McLaskey AK, Forster I, Hunt BPV (2021) Experimentally derived estimates of turnover and modification for stable isotopes and fatty acids in scyphozoan jellyfish. Journal of Experimental Marine Biology and Ecology 545, 151631; https://doi.org/10.1016/j.jembe.2021.151631McLaskey et al. 2024
Contact
Dr. Anna McLaskey
E-mail: a.mclaskey@oceans.ubc.ca