Analysis of microdialysate monoamines, including noradrenaline, dopamine and serotonin, using capillary ultra-high performance liquid chromatography and electrochemical detection

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Analytical technologies in the biomedical and life sciences, 2014-03, Vol.951-952, p.52-57
• Main Authors: Ferry, Barbara, Gifu, Elena-Patricia, Sandu, Ioana, Denoroy, Luc, Parrot, Sandrine
• Format: Article
• Language: English
• Subjects: Animals; Biogenic Monoamines - analysis; Biogenic Monoamines - isolation & purification; Brain; Brain Chemistry; Capillarity; Chromatography; Chromatography, High Pressure Liquid - methods; Dopamine; Electrochemical detection; Electrochemical Techniques; Limit of Detection; Linear Models; Liquid chromatography; Microdialysis; Microdialysis - methods; Monoamine neurotransmitter; Noradrenaline; Rats; Repeatability; Reproducibility of Results; Serotonin; Ultra high performance liquid chromatography
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2014.01.023

•Brain microdialysis sampling requires the analysis of monoamine traces.•Current HPLC-ED methods are not suitable for the analysis of monoamines in microdialysis samples≤5μL.•Capillary sub-2μm columns allow simultaneous monitoring of monoamines in 1μL samples.•A capillary ultra-HPLC–ED method has been optimized and validated for microdialysates. Electrochemical methods are very often used to detect catecholamine and indolamine neurotransmitters separated by conventional reverse-phase high performance liquid chromatography (HPLC). The present paper presents the development of a chromatographic method to detect monoamines present in low-volume brain dialysis samples using a capillary column filled with sub-2μm particles. Several parameters (repeatability, linearity, accuracy, limit of detection) for this new ultrahigh performance liquid chromatography (UHPLC) method with electrochemical detection were examined after optimization of the analytical conditions. Noradrenaline, adrenaline, serotonin, dopamine and its metabolite 3-methoxytyramine were separated in 1μL of injected sample volume; they were detected above concentrations of 0.5–1nmol/L, with 2.1–9.5% accuracy and intra-assay repeatability equal to or less than 6%. The final method was applied to very low volume dialysates from rat brain containing monoamine traces. The study demonstrates that capillary UHPLC with electrochemical detection is suitable for monitoring dialysate monoamines collected at high sampling rate.