Overview

Lipidomics is the large-scale study of cellular lipids — their identity, abundance, spatial distribution, and biological roles. Lipids are remarkably diverse in structure, encompassing fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, and prenols, each with numerous subspecies differing in chain length, degree of unsaturation, and head group composition. This structural diversity translates into functional diversity: lipids are the building blocks of biological membranes, serve as signaling molecules, and function as energy stores. Lipidomics aims to capture this complexity using mass spectrometry-based workflows that can detect hundreds to thousands of distinct lipid species in a single analysis.

Methods

Shotgun lipidomics introduces the total lipid extract directly into the mass spectrometer by infusion, using the mass differences between lipid classes and the characteristic fragmentation patterns of head groups for identification. LC-MS lipidomics couples liquid chromatography — typically reversed-phase for separation by hydrophobicity and normal-phase for class separation — with high-resolution mass spectrometry. Data analysis pipelines assign lipid identities by matching accurate mass, retention time, and MS/MS spectra against databases such as LipidMAPS. Software tools quantify lipids using class-specific response factors and correct for isotopic overlap. Imaging mass spectrometry reveals the spatial distribution of lipids within tissues.

Applications

Lipidomics is central to understanding metabolic diseases including obesity, diabetes, and atherosclerosis. It characterizes membrane remodeling in cancer, identifies lipid mediators of inflammation (eicosanoids), and profiles lipid storage disorders. The field integrates with lipid structure and classification principles, mass spectrometry analytics, and metabolic studies of cholesterol metabolism and fatty acid oxidation and synthesis.