Chemical Pathology Laboratory, Department of Pathology, Princess Margaret Hospital, Hong Kong

A method is described for the determination of blood methanol, ethanol, isopropanol and acetone by gas chromatography-mass spectrometry (GCMS) - selective ion monitoring (SIM) using a non-polar HP-5MS column with split mode injection. The total run time is 10 minutes.

Gas chromatography - flame ionization detection (GC-FID) is commonly used for the detection of alcohols in biological samples. The GCMS method provides confirmative information but requires "headspace" inlet for the introduction of vaporized samples.

The common hardware set up for laboratories with GCMS is to have two inlets for two columns; one for the MS detector and one for the FID detector.

In our laboratory, the GCMS system has only one split/splitless inlet, column switching is needed between GC-FID and GCMS operations. This GCMS method for alcohols does not need a "headspace" inlet and column switching to FID; it may be a convenient alternative for laboratories with limited resources.