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the two, lower chromatograms were monitored using the specific ions having m/z values of 143 and
146 respectively. It follows, that the peaks depicted on the single ion monitoring chromatograms
represent metabolites in which the D-ring has been preserved. It is clear that the GC/MS technique can
be a valuable tool for following the metabolic processes associated with the 17a-alkyl anabolic steroids.

Hooijerink et al. [9], used a similar technique to determine anabolic esters in oily formulations and in
blood plasma. The work was carried out to develop a test that could be used for forensic purposes.
Anabolic steroids are often illegally used as growth promoting agents in livestock breeding the use of
which is prohibited in the European Community. The steroids are either injected intra-muscularly or
applied topically and are slowly adsorbed into the blood stream. In either case the steroids can be
detected in the blood plasma. The authors employed an automatic sample preparation apparatus, a
Hewlett-Packard 5890 gas chromatograph and a Model 5970 mass detector. 5 ml of plasma was diluted
with 5 ml of water and after centrifuging (1500g for 15 minutes) it was filtered through a 5 mm filter.
The filtrate was then passed through an activated solid phase extraction column (SPE C ), washed with
2
1.25 ml of 50% v/v methanol solution and the steroids were then eluted with 3 ml of pure methanol.

Figure 5.12
Mass Spectrum of Medroxyprogesterone Acetate
Showing the Molecular Ion Peak at m/z 482 (ref.9)