Determination of dopamine and its metabolites in microdialysates by capillary liquid chromatography with electrochemical detection.

A liquid chromatographic method with packed fused-silica capillary columns and amperometric detection for the determination of trace amounts of catecholamines in microdialysis samples has been developed. The analysis time for dopamine and the products of its metabolism does not exceed 10 min. The minimum detectable dopamine concentration in a 2-microliters sample is 0.05 microgram/l. The relative standard deviation in concentration determinations is +/- 0.03 (n = 10). The small sample volume required and the speed of analysis make it possible to analyse biologically important compounds with a rapidly changing concentration.