Capillary column gas chromatographic profile analysis of volatile compounds in sera of normal and virus infected patients

A method is described whereby a transevaporator is used for sampling 60-100 pl of aqueous sample. Volatiles are stripped from the sample either by a stream of hel ium and collection on a porous polymer, Tenax, or by 0.8 ml of 2-chloropropane and collected on glass beads. The volatiles are thermally desorbed into a precolumn which is connected to a capillary gas chromatographic column for analysis. The technique is shown to be reproducible and suitable for determining chromatographic profiles for a wide variety of sample types. Using a transevaporator sampling technique, the volatile profiles from 70 pl of serum were obtained by capillary column gas chromatography. The complex chromatograms were interpreted by a combination of manual and computer techniques and a two peak ratio method devised for the classification of normal and virus infected sera. Using the K-Nearest Neighbor approach, 85.7% of the unknown samples were classified correctly. Some preliminary results indicate the possible use of the method for the assessment of virus susceptibility.