The n-3 PUFA content of the global lipidomes of NIST SRM 2378, SRM 1950, and intralaboratory quality control materials

The regular use of commercially available Standard Reference Materials (SRM) and intralaboratory quality control materials, which are important tools, is essential for standardizing and ensuring high-quality lipidomic analyses. These materials should also be relevant for the research application. To support nutritional lipidomic research, the global lipidome of materials derived from individuals consuming a range of n-3 PUFAs was determined. Nontargeted lipidomics were completed on SRM 2378 (serum), SRM 1950 (plasma), and intralaboratory quality control (plasma) generated from individuals with low omega-3 and high omega-3 status. SRM 2378 includes materials generated from individuals consuming fish oil (SRM 2378-1), flaxseed oil (SRM 2378-2), and no supplements (SRM 2378-3). Specific lipids with differences were identified using fold-based and absolute differences in semiquantitated concentrations. Individual lipids containing 20:5 and 22:6 were highly variable and largely reflected ad hoc intake estimates of EPA and DHA. Fold-based approaches identified low-abundant lipids that differed, whereas absolute differences identified high-abundant lipid species that differed. In addition, differences due to dietary fatty acid intakes were more dramatic than differences between serum and plasma in these nontargeted analyses. The dietary intake of EPA and DHA can impact lipidomic profiles, which should be considered by lipidomic analysts. These results also suggest that comprehensive dietary assessments should be considered during the development of reference and quality control materials.