title: New antioxidant mixture for long term stability of serotonin, dopamine and their metabolites in automated microbore liquid chromatography with dual electrochemical detection.
abstract: An automated microbore liquid chromatographic assay with dual electrochemical detection is described for the determination of serotonin, dopamine and their metabolites, 5-hydroxyindoleacetic acid, 3,4-dihydroxyphenylacetic acid and homovanillic acid. Due to the chemical instability of the compounds, the addition of an antioxidant is required for automated analysis over a long period of time (e.g., 20 h). Therefore, the time stability of these substances was tested with different antioxidants. The stability for serotonin and 5-hydroxyindoleacetic acid was poor in acidic medium containing Na2EDTA but could greatly be improved by the addition of L-cysteine and ascorbic acid. Using this assay, the neurotransmitters and their metabolites could easily be determined in microdialysates obtained from different rat brain areas.
authors.affiliation: Department of Pharmaceutical Chemistry and Drug Analysis, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Thorré
authors.forename: M
authors.initials: M
authors.lastname: Pravda
authors.forename: S
authors.initials: S
authors.lastname: Sarre
authors.forename: G
authors.initials: G
authors.lastname: Ebinger
authors.forename: Y
authors.initials: Y
authors.lastname: Michotte
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000975:Antioxidants; D001205:Ascorbic Acid; D002853:Chromatography, Liquid; D003545:Cysteine; D004298:Dopamine / Q000032:analysis* / Q000378:metabolism; D004355:Drug Stability; D004492:Edetic Acid; D004563:Electrochemistry; D006719:Homovanillic Acid / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D006897:Hydroxyindoleacetic Acid / Q000032:analysis; D017551:Microdialysis; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012701:Serotonin / Q000032:analysis* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D015102:3,4-Dihydroxyphenylacetic Acid; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D004492:Edetic Acid; D003545:Cysteine; D001205:Ascorbic Acid; D004298:Dopamine; D006719:Homovanillic Acid