title: High sensitivity HPLC assay for GABA in brain dialysis studies.
abstract: The measurement of GABA in brain dialysis experiments involves precolumn derivatization of the amino acid with o-phthaldehyde (OPA) in the presence of a thiol and subsequent high-pressure liquid chromatography with electrochemical detection. A method is described which employs an internal standard and coulometric preoxidation (+ 0.2 V) to eliminate unconjugated OPA/thiol prior to final oxidation (+ 0.4 V) of the derivatized sample. This allows for more efficient separation, providing a retention time for GABA of 9-10 min, a detection sensitivity of 2 to 5 x 10(-14) mol/sample and chromatographic stability for at least 2 weeks of daily use.
authors.affiliation: Department of Veterinary Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman 99164-6520.
authors.forename: A
authors.initials: A
authors.lastname: Bourdelais
authors.forename: P W
authors.initials: PW
authors.lastname: Kalivas
mesh_terms: D000097:Acetonitriles; D000596:Amino Acids / Q000032:analysis; D021542:Amino Acids, Neutral; D000818:Animals; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid; D003956:Dialysis; D006863:Hydrogen-Ion Concentration; D008832:Microchemistry; D009557:Nipecotic Acids / Q000494:pharmacology; D010084:Oxidation-Reduction; D011392:Proline / Q000031:analogs & derivatives*; D051381:Rats; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
chemical_list: D000097:Acetonitriles; D000596:Amino Acids; D021542:Amino Acids, Neutral; D009557:Nipecotic Acids; C030278:nipecotic acid; D005680:gamma-Aminobutyric Acid; C013809:5-aminovaleric acid; D011392:Proline; C010983:homoproline; C032159:acetonitrile