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an appropriate solvent. Alternatively, it can be trapped on a suitable adsorbent contained in a packed
tube, and then thermally desorbed into the carrier gas of a gas chromatograph.
Figure 4.9
The Separation of a Sample of Basil Oil
Courtesy of the Perkin Elmer Corporation
The column that was used in this example, was a macro-bore open tubular column, 50 m long, 0.32 mm
in diameter and carried a 5 mm film of a methyl silicone. The chromatogram was obtained by plotting
the integrals of each adsorption curve against time. The chromatogram of oil of basil, obtained in this
way, is shown in Figure 4.9. The light pipe was maintained at 250°C and the scavenger flow was set at
1 ml/min. Each point on the chromatogram resulted from the sum of two consecutive spectra. A
spectrum, taken at the peak maximum of linalool (peak 4), is shown in Figure 4. 10. It is seen that a
clean spectrum is obtained and the resolution from the macro-bore capillary column does not appear to
have been denigrated. It has been claimed that spectra, with adequate resolution and signal-to-noise for
solute identification, have been obtained from as little as 10 ng of material. However, the minimum
sample size that can
