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minutes to obtain the supernatant layer of methanol, which contained the steroids. A sample of the
methanol layer was placed on the column. The separation was carried out on a Zorbax column, 25 cm
long, 4.6 mm I.D., packed with a reversed phase, ODS 5U C18. The nebulizer temperature was set at
30°C and the transport stage at 35°C. The chromatogram was obtained from a UV monitor. The first
peak can be identified from its spectrum as the preservative, benzyl benzoate, and the second as
testosterone cypionate. The benzyl benzoate has a large extinction coefficient and produces a
disproportionally strong UV absorption peak. The spectra of the active component clearly shows the
dual carbonyl peaks at 1676 and 1732 cm-l that correspond to the ketone and ester carbonyl groups.
Adequate spectra could be obtained from 100 ng of sample deposited on the disk. However, if the
technique were to be used for the analysis of blood or urine, a solid phase extraction stage would be
necessary to obtain sufficient sample at a satisfactory concentration. Two examples of some spectra
taken with the Lab Connections instrument, for the identification of specific drug precursors or
derivatives are shown in Figure 8.17.

Figure 8.17
Spectra of a Drug Precursor and a Drug
Derivative Taken from the LC Column Eluent
Courtesy of Lab Connections Inc. (The spectra of the AZT
derivative was kindly supplied to Lab Connections Inc.
by Dr. Phyllis Brown and John Imari of Rhode Island)

It is seen that the spectra exhibit significant fine structure and would be quite satisfactory for
confirming the identity of a specific drug or