title: 5-Hydroxytryptophan: A method for monitoring human plasma content during clinical administration.
abstract: A method is described for the assay of 5-hydroxytryptophan (5-HTP) in human blood plasma following administration of the compound. The procedure involves extracting the amino acid into butanol, returning the 5-HTP to an aqueous phase, and separating it from other interfering 5-hydroxyindoles on a column of Dowex 50W-X4, a strong cation-exchange resin. The concentration of 5-HTP in the buffer eluate is determined spectrofluorometrically in 3 N HCl; 25 ng/ml plasma can be detected. Using this method, it was possible to determine the time-course of plasma 5-HTP concentrations during the 24-h period after a single 300-mg dose. 5-HTP is being utilized in clinical trials for several psychiatric and neurological disorders.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 94305, Stanford, California.
authors.forename: P
authors.initials: P
authors.lastname: Angwin
authors.forename: P
authors.initials: P
authors.lastname: Berger
authors.forename: V
authors.initials: V
authors.lastname: Zarcone
authors.forename: H K
authors.initials: HK
authors.lastname: Brodie
authors.forename: J
authors.initials: J
authors.lastname: Barchas