Analysis of serotonin in brain microdialysates using capillary electrophoresis and native laser-induced fluorescence detection

• Published in: Electrophoresis Vol. 26; no. 6; pp. 1071 - 1079
• Main Authors: Benturquia, Nadia, Couderc, François, Sauvinet, Valérie, Orset, Cyrille, Parrot, Sandrine, Bayle, Christophe, Renaud, Bernard, Denoroy, Luc
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.03.2005; WILEY‐VCH Verlag
• Subjects: Animals; Brain Chemistry - drug effects; Capillary electrophoresis; Citalopram - pharmacology; Electrophoresis, Capillary - methods; Fenclonine - pharmacology; Hydrogen-Ion Concentration; Laser-induced fluorescence detection; Lasers; Male; Microdialysis; Microdialysis - methods; Rats; Rats, Sprague-Dawley; Sensitivity and Specificity; Serotonin; Serotonin - analysis; Serotonin - isolation & purification; Spectrometry, Fluorescence - methods
• ISSN: 0173-0835; 1522-2683
• DOI: 10.1002/elps.200410150

Serotonin or 5‐hydroxytryptamine (5‐HT) is a major neurotransmitter in the central nervous system. In this work, a method for analyzing 5‐HT in brain microdialysis samples using a commercially available capillary electrophoresis (CE) system has been developed. A pH‐mediated in‐capillary preconcentration of samples was performed, and after separation by capillary zone electrophoresis, native fluorescence of 5‐HT was detected by a 266 nm solid‐state laser. The separation conditions for the analysis of 5‐HT in standard solutions and microdialysates have been optimized, and this method has been validated on both pharmacological and analytical bases. Separation of 5‐HT was performed using a 80 mmol/L citrate buffer, pH 2.5, containing 20 mmol/L hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) and +30 kV voltage. The detection limit was 2.5×10−10 mol/L. This method allows the in vivo brain monitoring of 5‐HT using a simple, accurate CE measurement in underivatized microdialysis samples.