Separation of R-form lipopolysaccharide and lipid A by CE-Fourier-transform ion cyclotron resonance MS.
Lipopolysaccharide (LPS) is the main component of the outer leaflet of the outer membrane of Gram-negative bacteria. Native isolates of LPS comprise a high inherent heterogeneity. This paper presents the first application of CE to separate and online mass analyze the different constituents of underivatized R-form LPS and lipid A with an FT ion cyclotron resonance mass spectrometer. A Beckman P/ACE MDQ and a home-made CE instrument were coupled to the mass spectrometer using a sheath liquid interface. An optimized CE electrolyte based on water, isopropyl alcohol, triethylamine and acetic acid at pH 8.9 allowed the separation of molecular species even of complex mixtures to a large extent with observed detection limits of single constituents of the samples in the low femtomol range. Comparison of CE-MS and MS measurements under equal conditions enabled the investigation of ion suppression effects in LPS samples.
Division of Immunochemistry, Research Center Borstel, Borstel, Germany.
Göran
G
Hübner
Buko
B
Lindner
D017357:Cyclotrons; D019075:Electrophoresis, Capillary / Q000379:methods*; D005583:Fourier Analysis; D008050:Lipid A / Q000302:isolation & purification*; D008070:Lipopolysaccharides / Q000302:isolation & purification*; D013058:Mass Spectrometry / Q000379:methods*; D040901:Proteomics
D008050:Lipid A; D008070:Lipopolysaccharides