Opinion article on lipidomics: Inherent challenges of lipidomic analysis of sphingolipids.

A challenge for sphingolipidomic analysis is the vast number of subspecies, including a large number of isomers-a complication that was even appreciated by the original discoverer of sphingolipids J. L. W. Thudichum (The Chemistry of the Brain, p. x, 1884): "In the course of my researches many unforeseen complications arose, prominent amongst which were those caused by the occurrence of chemical principles having the same atomic or elementary composition, but differing in other chemical, or in physical properties, varieties producing the phenomenon which in chemistry is termed isomerism." Therefore, it is essential to choose the appropriate method(s) for the goal of the analysis, to know the assumptions and limitations of method(s) used, and to temper interpretation of the data accordingly. This article is part of a Special Issue entitled: BBALIP_Lipidomics Opinion Articles edited by Sepp Kohlwein.