In living organisms, lipids are essential for the assembling of cellular membranes, the storage of metabolic energy, and as signaling molecules in cell metabolism. The Lipidomics Facility analyzes lipids from biological samples using the latest mass spectrometric techniques, thus making a key contribution towards exploring their functions.
Services: The Lipidomics Facility offers CECAD scientists the analysis of lipids in biological samples using state-of-the-art mass spectrometric techniques and data processing software. The service also includes help with the experimental design and data interpretation.
Scientific achievements: The Lipidomics Facility originally focused on the targeted analysis of sphingolipids. The Facility’s expertise was then subsequently extended to the quantification of further lipid classes such as glycerophospholipids and sterols.Upon move of the Lipidomics Facility into the CECAD Research Center in February 2014, two new-generation mass spectrometers (QTRAP 6500 and TripleTOF 5600+, AB SCIEX) equipped with two Liquid Chromatography systems (1260 Infinity, Agilent; Ekspert MikroLC 200, Eksigent), a chip-based infusion system for Nano-Electrospray Ionization (TriVersa NanoMate, Advion) and an interface for Differential Mobility Spectrometry (SelexION, AB SCIEX) were purchased. Thereby the Facility obtained full flexibility for applying all of the latest lipidomic technqiues. Depending on the lipid class and scientific question analytical methods with (LC-MS/MS) or without (shotgun lipidomics) pre-separation of the lipid extract prior to the mass spectrometric analysis are possible. A comprehensive software package for data processing and evaluation facilitates the handling of large data sets.
Future plans: Whereas the targeted quantification of lipids is well-established in the Lipidomics Facility, the new equipment also enables non-targeted profiling of lipids in complex extracts. In the long term the Facility plans to expand its service towards more general metabolomics applications by integrating metabolites of the glycolysis, the citric acid cycle and the pentose phosphate pathway into the set of service analyses.
Figure 1: Non-targeted profiling of lipids by Information Dependent Acquisition (IDA): A lipid extract from mouse liver was separated by Liquid Chromatography (LC). The LC eluate was infused into the TripleTOF 5600+ mass spectrometer and monitored by IDA. In IDA experiments MS/MS spectra are recorded automatically when data in the survey MS spectra meet certain criteria. Every data point in the plot represents the retention time and the m/z ratio of a lipid ion that was selected as a precursor ion.
Figure 2: Targeted analysis of lipids by Multiple Precursor Ion Scanning (MPIS): A lipid extract from keratinocyte mitochondria was infused into the QTRAP 6500 mass spectrometer using the chip-based TriVersa NanoMate infusion system. Glycerophospholipid subclasses (phosphatidylcholine, -ethanolamine, -serine, -inositol, -glycerol, and phosphatidic acid) were simultaneously detected by applying specific precursor ion and neutral loss scans for each subclass. Each peak in the mass spectrum represents a glycerophospholipid species with a distinct fatty acid composition.
We charge our routine analyses. Graduated charges apply for the different user groups (CECAD members, members of the University of Cologne, external scientists). For inquiries please contact Dr. Susanne Brodesser.