Confirmatory and quantitative analysis is typically performed by gas chromatographic GC analysis.
The highly polar nature of the drugs in both the salt and free base forms cause strong interactions with surfaces such as the inlet and stationary phase in the GC; these interactions Nature Of Crime Analysis problematic, especially for quantitation. Our laboratory recently developed a method to attenuate this surface interaction that resulted in improved chromatographic behavior and detector response by mass spectrometry MS. We have established that derivatization of the basic nitrogen with alkanoic anhydrides enhances the sensitivity of the assay significantly.]
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