Electrospray ionization/mass spectrometry compatible reversed-phase separation of phospholipids: piperidine as a post column modifier for negative ion detection

An electrospray ionization (ESI) compatible separation of phospholipids (PL ), phosphatidylglycerol (PG), phosphatidyl ethanolamine (PE), and phosphati dylcholine (PC), was performed on a C18 column by reversed phase High Perfo rmance Liquid Chromatography (HPLC) with minimal ESI suppression. The mobil e phase,used isocratically, consisted of methanol and water. ESI was used t o efficiently transfer the ions present in solution to the gas phase for ma ss spectrometric (MS) detection. Formation of negative ions was reinforced by incorporating piperidine post column. Limits of detection (LOD) and limi ts of quantitation (LOQ) were experimentally determined to be 20 and 60 fmo l/mu l, respectively, when acquiring data in the selected ion monitoring (S IM) mode monitoring three ions with a single quadrupole MS. When acquiring data from m/z 110-900 in the scanning mode, the LOD and LOQ were experiment ally determined to be 1 pmol/mu l and 3 pmol/mu l. When acquiring product i on spectra for m/z 747, the LOD and LOQ were experimentally determined to b e 446 attomol/mu l and 1.3 fmol/mu l, respectively. (C) 2000 Elsevier Scien ce B.V. All rights reserved.