The determination of amphetamine and methamphetamine in a lyophilized human urine reference material

The concentrations of amphetamine and methamphetamine in a new lyophilized human urine reference material (RM) were determined at the National Institute of Standards and Technology, in cooperation with the College of American Pathologists. In order to minimize the possibility of undetected bias, two different methods were developed. Both methods were based on isotope-dilution gas chromatography/mass spectrometry (GC/MS) with a deuterium-labeled standard. The first method used a solid phase extractor (SPE) to isolate the analytes, followed by forming the heptafluorobutyryl (HFB) derivatives for measurement by GC/MS. The second method used another kind of SPE to isolate the analytes, followed by forming the N-trifluoroacetyl-1-prolyl chloride (TPC) derivatives for measurement by GC/MS. The RM consists of three levels of amphetamine, three levels of methamphetamine, and a blank. For amphetamine, the concentrations are 291, 558, and 1081 ng/mL of human urine. For methamphetamine, the concentrations are 311, 573, and 1137 ng/mL of human urine.