The ion-pair extraction, purification, and liquid chromatographic analysis of indolealkylamines in human urine

A highly efficient ion-pair extraction technique for the isolation of tryptamine, 5-hydroxytryptamine, and their mono- and N,N-dimethylated derivatives from aqueous media is described. The technique has been used to isolate nanogram quantities of both N, N-dimethyltryptamine and 5-hydroxy-N, N-dimethyltryptamine from large volumes of urine. A rapid and efficient normal-phase liquid chromatographic procedure has also been developed for the subsequent purification of indolealkylamines isolated from urine. The methods described have been used in the measurement of the urinary excretion of 5-hydroxy-N, N-dimethyltryptamine. Analyses were performed by liquid chromatography using a cation-exchange column with online fluorescence detection. Further characterization was achieved by stop-flow spectroscopic analysis of the LC eluant.