HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY ELECTROSPRAY-IONIZATION - TANDEM MASS-SPECTROMETRY FOR THE ANALYSIS OF 1,2,3,4-TETRAHYDRO-BETA-CARBOLINE DERIVATIVES

A rapid and sensitive method is described for the detection of 1,2,3,4 -tetrahydro-beta-carboline-3-carboxylic acid, hyl-1,2,3,4-tetrahydro-b eta-carboline-3-carboxylic acid and 1-methyl-1,2,3,4-tetrahydro-beta-c arboline by electrospray ionization tandem mass spectrometry coupled t o liquid chromatography. In combination with selected reaction monitor ing (SRM) detection limits of 3 ng ml(-1) (ca. 75 fmol on column) were established by the use of model solutions. Due to the excellent selec tivity and sensitivity of SRM no sample preparation step was required prior to analysis of food samples. In addition, any artifactual format ion of tetrahydro-beta-carbolines could be excluded. Application of th e method revealed that all food samples analyzed contained both tetrah ydro-beta-carboline-carboxylic acids at ng ml(-1) to mu g ml(-1) conce ntrations, whereas 1-methyl-1,2,3 ,4-tetrahydro-beta-carboline was ide ntified in most samples as a minor constituent.