title: Analysis of cerebrospinal fluid γ-aminobutyric acid by capillary electrophoresis with laser-induced fluorescence detection.
abstract: The measurement of γ-aminobutyric acid (GABA) is suitable for investigating various neurological disorders. In this study, a sensitive and selective method for free GABA quantification in cerebrospinal fluid (CSF) has been standardised. This method is based on CE with LIF detection using 4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-F) as a derivatisating agent. The reaction conditions (NBD-F concentration, pH, temperature and reaction time) and the electrophoretic parameters (run buffer composition and pH and separation voltage) were optimised to obtain the maximum derivatisation efficiency and electrophoretic resolution. The best resolution was obtained using 200 mM sodium borate, 10 mM SDS, 8.5 mM β-CD, pH 10 and 20 kV voltage. The method was linear in the concentration range of 2.5-1000 nM with good inter- and intra-assay precision values. The effects of CSF handling on free GABA concentrations were also evaluated. Our results show that the time delay between CSF collection and freezing strongly increases the CSF GABA values. Age-related reference values were established in 55 paediatric controls. The influence of antiepileptic therapy on free CSF GABA was studied in 38 neuropaediatric patients. Significantly, higher GABA values were obtained in patients taking valproic acid or vigabatrin therapy, which are antiepileptic drugs that modulate GABA metabolism.
authors: Department of Clinical Biochemistry and Neuropaediatrics, Hospital Sant Joan de Déu-CIBERER-ISCIII, Barcelona, Spain; Department of Biochemistry and Molecular Biology, UAB, Barcelona, Spain.
authors: Mercedes
authors: M
authors: Casado
authors: Marta
authors: M
authors: Molero
authors: Cristina
authors: C
authors: Sierra
authors: Angels
authors: A
authors: García-Cazorla
authors: Aida
authors: A
authors: Ormazabal
authors: Rafael
authors: R
authors: Artuch
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D005453:Fluorescence; D006801:Humans; D007223:Infant; D007834:Lasers; D057230:Limit of Detection; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000134:cerebrospinal fluid*
chemical_list: D005680:gamma-Aminobutyric Acid
keywords: CE; Cerebrospinal fluid; Paediatric population; γ-Aminobutyric acid