2.Targeted Lipidomics and Absolute Quantitation
Targeted lipidomics enables the focused analysis of a known collection of lipids. Precise method development allows for the inclusion of equal amounts of isotope-labeled or odd-chain internal standards selected from customizable lipid panels. Lipids from each sample are extracted using standardized protocols and analyzed by LC-MS/MS using analyte-specific collision-induced mass transitions from the molecular ion (or, in some cases, from a known adduct) to a characteristic fragment ion. Analyte concentrations are determined from calibration curves prepared from authentic standards, when available, or surrogate standards when necessary. This approach is especially useful for quantifying lipids present at low levels in samples, such as endogenous bioactive lipids (e.g., prostaglandins, leukotrienes, or endocannabinoids). Standard statistical analysis tools can reveal changing trends in lipid species among experimental groups, which can be visualized with a heat map or other available graphical tools.
TARGETED LIPID PANELS
Maximize data from precious samples with established targeted lipid panels offering the sensitivity, efficiency, and specificity needed to identify and quantify biologically relevant lipids.
- Eicosanoids and Oxylipins
- Eicosanoids derived from arachidonic acid
- Oxidized mediators derived from linoleic acid, eicosapentaenoic acid, and docosahexaenoic acid
- Sphingolipids
- Sphingoid bases, ceramides, monohexosylceramides, dihexosylceramides, and sphingomyelins
- Endocannabinoids and Endocannabinoid-like Lipids
- N-acylethanolamides, acylglycerols, N-acyltaurines, N-acylglycines, N-acylserines, N-acyldopamines
- Urinary Lipid Metabolites
- Indicative of the production, metabolism, and excretion of eicosanoids and other bioactive lipids
- Cholesterol Esters
- Cholesterol esterified with saturated or unsaturated acyl chains
- Short-Chain Fatty Acids
- Fatty acids with up to six carbons, many of which are produced by gut microbiota
- Phospholipids
- Specific acyl chains (e.g., 20:4) or oxidized acyl chains (e.g., 20:4-OH, 20:4-OOH)