Lipidomics Platform
The IMBIO Institute,AG Dörmann, provides a lipid analytical platform for the campus of the University of Bonn in the framework of the SFB645. We measure a large variety of lipids in a quantitative manner employing state-of-the art analytical equipment, including fluorescence HPLC, gas chromatography (GC), GC-MS and Q-TOF (quadrupole time of flight) mass spectrometry (Figure 1).
Figure 1: Equipment of the lipidomics platform at the IMBIO Institute, University of Bonn
From left to right: Agilent 1100 HPLC, Agilent GC and GC-MS, Agilent Q-TOF (quadrupole time-of flight) mass spectrometer equipped with Agilent Chipcube nanospray, APCI and ESI source.
If you are interested in lipid measurements at the lipidomics facility of University of Bonn, please check the class(es) of lipids you are interested in (this page). To cover the expenses for solvents, LC columns, and parts for chromatography and mass spectrometry, we ask for a contribution according to the table shown on this page (costs). Protocols for lipid extraction are available (boiling-water-protocol) or (acidic chloroform-methanol extraction).
For questions please contact:
Head of Department and Managing Director of IMBIO
Prof. Dr. Peter Dörmann [Email protection active, please enable JavaScript.]
Lipidomics Service Team
Dr. Katharina Gutbrod [Email protection active, please enable JavaScript.]
Helga Peisker [Email protection active, please enable JavaScript.]
Lipids measured by the lipidomics platform (Letters in brackets indicate cost calculation)
Lipid isolation (A)
Glycerolipids
are isolated from leaves, bacteria and fungi using the boiling-water
protocol, or from animal tissues or from plant roots with acidic
chloroform-methanol extraction.
Solid phase extraction (SPE) on silica columns (B)
SPE
on silica columns is used to separate neutral lipids (triacylglycerol,
diacylglycerol), glycolipids (galactolipids, hexosylceramides),
phospholipids and lyso-phospholipids, and for the separation of sterol
lipid classes from plants.
Phospholipids/Galactolipids (membrane glycerolipids) from plants, bacteria and fungi (A, C)
Phospholipid and galactolipid
from plants, bacteria and fungi are isolated using the boiling-water
protocol or the acidic chloroform-methanol extraction and measured by
tandem mass spectrometry (Q-TOF MS/MS). Lipids are quantified by MS/MS
experiments with internal standards following the strategy developed by
Ruth Welti (Kansas State University) (also see: Gasulla et al., 2013).
Lyso-phospholipids (A, B, C)
After
lipid isolation, lyso-phospholipids (lyso-PC) are purified by SPE on
silica columns prior to measurement by direct infusion Q-TOF mass
spectrometry.
Sphingolipids from animals (please contact us)
The
sphingolipid composition from animals (ceramide, hexosylceramide,
sphingomyelin, gangliosides,sulfatides) can be measured after alkaline
hydrolysis of phospholipids. Neutral and acidic sphingolipids are
separated by solid phase extraction and quantified by direct infusion
Q-TOF MS/MS.
Sphingolipids from Plants (please contact us)
Plant
sphingolipids in crude lipid extracts are purified by alkaline
hydrolysis of phospholipids and galactolipids. Glucosylceramides from
plants can be measured by direct infusion with the Q-TOF mass
spectrometer after SPE on silica columns.The full spectrum of
sphingolipids (ceramide, glucosylceramide, sphingobase, GIPC) can be
measured by LC-MS/MS following a protocol developed by Jonathan Markham
(University of Lincoln Nebraska).
Triacylglycerol, Diacylglycerol (A, B, C)
Triacylglycerol
and diacylglycerol are isolated from the sample using the boiling-water
protocol or the acidic chloroform-methanol extraction and then
separated from polar lipids by SPE on silica columns. Triacylglycerol
and diacylglycerol are quantified by direct infusion mass spectrometry
(Q-TOF) (Lippold et al., 2012; vom Dorp et al., 2013).
Fatty acids (E, F)
Total
fatty acids in biological samples can be quantified after conversion of
all acyl groups into fatty acid methyl esters. The methyl esters are
quantified by gas chromatography (GC) with flame ionization detector
using pendadecanoic acid (15:0) as internal standard. For structural
identification, fatty acid methyl esters are analyzed by gas
chromatography-mass spectrometry (GC-MS).
Sterol lipids (A, B, C, E, F)
Free
sterols can be measured by GC-MS after silylation, and total sterols
(free and conjugated) sterols can be measured in the same way after
acidic/alkaline hydrolysis and silylation (A, E, F)
In order to
analyze the full spectrum of free and conjugated sterols, the sterol
lipid classes are separated by SPE on silica columns into a polar
fraction (only present in plants and some fungi: sterol glucosides,
acylated sterol glucosides) and a non-polar fraction (free sterols,
sterol esters). These fractions are measured separately by direct
infusion Q-TOF MS (A, B, C). Free sterols need to be derivatized e.g.
with chlorobetainyl chloride prior to quantification (Wewer et al.,
2010).
