Comprehensive profiling analysis of bioamines and their acidic metabolites in human urine by gas chromatography/mass spectrometry combined with selective derivatization.

ABSTRACT

A comprehensive analytical method was developed for the profiling of biogenic amines in human urine using GC/MS in SIM mode. Biogenic amines and their acidic metabolites were converted into their volatile O-trimethylsilyl/N-heptafluorobutyryl (OTMS/-NHFBA) derivatives for GC/MS analysis. Dual hexamethyldisilazane (HMDS)/-N-methyl-bis-heptafluorobutyramide (MBHFBA) derivatizations have been shown to be quite effective, with high derivatization yields and the absence of side products for primary biogenic amines. In this study, selective derivatization conditions by HMDS/MBHFBA were optimized in terms of the reagent amount, reaction temperature and reaction time period. The highest derivatization reaction yield was obtained at 40°C for 10min for OTMS derivatization and 80°C for 5min for N-HFBA derivatization. The use of MCX SPE cartridges with different SPE elution solvents was effective for the pre-concentration and selective cleanup of the biogenic amines and their acidic metabolites in human urine. The selection of appropriate ions in SIM mode provided reliable quantification and identification and a reduction in background effects. The established method was validated in terms of linearity, limits of detection (LOD), limits of quantification (LOQ), precision, and accuracy. The present method was linear (r(2)>0.996), reproducible (relative standard deviation range 1.1-6.9%), and accurate (range 87.9-111.9%), with LOQs of 0.17-17.84ng/mL. The biogenic amine profiling of human urine was successfully accomplished by GC/MS in SIM mode combined with selective HMDS/MBHFBA derivatization and MCX SPE cleanup.