Aim: Plasma and serum are widely used blood-derived biofluids for metabolomics and lipidomics assays, but analytes that are present in high concentrations in blood cells cannot be evaluated in those samples and isolating serum or plasma could introduce additional variability in the data. Materials & methods: In this study, we provide a comprehensive method for quantification of the whole blood (WB) sphingolipidome, combining a single-phase extraction method with LC–high-resolution mass spectrometry. Results: We were able to quantify more than 150 sphingolipids, and when compared with paired plasma, WB contained higher concentration of most sphingolipids and individual variations were lower. These findings suggest that WB could be a better alternative to plasma, and potentially guide the evaluation of the sphingolipidome for biomarker discovery.
Lay abstract
Whole blood (WB) is a mixture of different cellular and acellular components including red blood cells, white blood cells, platelets and plasma. Ceramides, one class of sphingolipids, have been reported as promising biomarkers of cardiac events and several other pathologies, but their plasma concentrations vary depending on diet, time of day and other factors. In this study, we established a comprehensive method for the quantification of the WB sphingolipidome. We were able to quantify more than 150 sphingolipids, and when compared with paired plasma, WB contained higher concentration of most sphingolipids and individual variations were lower. These findings suggest that WB could be a better alternative to plasma, and potentially guide the evaluation of new biomarker discovery.
Graphical abstract
Keywords:
- ceramides
- high-resolution mass spectrometry
- plasma
- sphingolipids
- whole blood