Capillary gas chromatography/mass spectrometry of oxazaphosphorines

Extensive use of these agents has raised the demand for (bio) analytical assays in order to describe the pharmaceutical and pharmacokinetic (including metabolism) phase of the oxazaphosphorines. Several methods were introduced, based on TLC, GC, HPLC, and MS. For routine analysis, HPLC and GC 12, 31 are to be preferred but have some disadvantages: HPLC lacks sensitivity whereas GC generally needs derivatization. Capillary gas chromatography on polar columns proved to be capable of elution of CY and some of its metabolites without derivatization [4]. Capillary GC of underivatized CY resulted in partial degradation thereof, yielding intra-alkylated CY [41. Nevertheless, the formation of intra-alkylated CY was linear over a sufficient range allowing application of the assay in experimental and clinical sessions [5-71. This contribution describes CGC and CGC-MS analvsis of IF.