摘要：Stability of trifluoroacetyl (TFA), pentafluoropropionyl (PFP) and heptafluorobutyryl (HFB) derivatives of methamphetamine and its metabolites in man were investigated. TFA derivatives in solution were more stable than those in solid state, and solution of TFA derivatives in ethyl acetate or n-hexane was stable at 5°C for a few hours. Although PFP and HFB derivatives were more stable than the corresponding TFA derivatives, it took long time for the removal of excess reagent after preparation of the derivatives. TFA, PFP and HFB derivatives of methamphetamine, amphetamine and norephedrine were stable, and those of aromatic hydroxylated metabolites were relatively unstable, especially TFA derivatives of p-hydroxynorephedrine was most unstable in these derivatives. Taking into account the facility in preparation of the derivatives, stability of the derivatives and cost of the reagents, it was practically most useful to prepare TFA derivatives and to apply ethyl acetate solution of the derivatives to gas chromatography within a few hours after preparation.
