Retention time bracketing for targeted sphingolipidomics by liquid chromatography–tandem mass spectrometry

Sphingolipids are lipids which play significant roles in many cellular functions and processes. Structurally diverse owing to differences in the sphingoid backbone, amide linked fatty acyl chain and functional polar head group, sphingolipids form interconnected metabolic networks which are biologically potent (Figure 1) [1–3]. Sphingolipids such as ceramide (Cer) and sphinghoid bases (sphingosine-1-phosphate; S1P) modulate apoptotic signaling events, while phosphorylation or glycosylation lead to the production of mitogenic factors such as ceramide-1-phosphates (C1P) and glucosylceramides (GlcCer) [4–7]. Clinically, sphingolipids play major roles in a number of endocrine and metabolic disorders and diseases such as diabetes, multiple sclerosis, cancer, gynecologic disorders and...