Analyses of lysophosphatidic acids by gas chromatography mass spectrometry without hydrolytic pretreatment.

Lysophosphatidic acids having different fatty acyl moieties were directly analysed by gas chromatography/mass spectrometry after silylation. Trimethylsilyl derivatives of various LPAs escaped thermal degradation, and electron impact and chemical ionization of these derivatives yielded many ions which were useful for the structural determination. It was found by this new method that five species of lysophosphatidic acids were formed in rat plasma during incubation at 37 degrees C.