Quantitative Investigation of Rapid Injector Port Derivatization of Amphetamine Using Trifluoroacetic Anhydride with Packed and Capillary Column GC and GC/MS Methods

Direct injector port derivatization of amphetamine through coinjection of sample with trifluoroacetic anhydride was quantitatively investigated and found to be a rapid and more sensitive alternative to longer solution-based derivatization procedures. Under optimum conditions determined in this work, limits of detection were 1 ng using gas chromatography with flame ionization detection and 1 pg using single ion monitoring of ion 140.0 amu (M-91+) in gas chromatography/mass spectrometry methods. The previously reported derivatization period of over 12 hr was greatly reduced using instantaneous derivatization with a 100- to 1000-fold increase in limits of detection. Effects of inlet temperature, mass of trifluoroacetic anhydride, and column pre-treatment on chromatographic performance are reported. Application to analysis of serum from amphetamine-dosed rats was used for comparison to accepted solution-based derivatization.