DETERMINATION OF ABSOLUTE-CONFIGURATIONS OF 2-HYDROXY AND 3-HYDROXY FATTY-ACIDS IN ORGANIC DUST BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

The absolute configurations of 2- and 3-hydroxy fatty acids in lipopolysaccharides and environmental samples were studied by gas chromatography-mass spectrometry (GC-MS). The acids were analyzed as (S)-phenylethylamide 2- and 3-methoxy derivatives. A simplified method for the preparation of these derivatives was developed by introducing trimethylsilyldiazomethane as the methylation agent. Both (R) and (S) forms of 2- and 3-hydroxy fatty acids of from 10 to 18 carbon atoms were identified in organic dust. This method may be useful for determination of environmental endotoxin by GC-MS.