A method for determining biogenic amine concentrations in extracts of brain tissue using high-performance liquid chromatography with electrochemical detection is described. Using a Hypersil stationary phase and a mobile phase based on methanol and containing 0.1%V/V sulphuric acid, the effects of varying methanol concentrations of the ion-pairing sodium octylsulphate have been investigated. The optimum separation conditions were achieved with a mobile phase containing 10%V/V methanol, 0.1%V/V sulphuric acid and 6 × 10–4 M sodium octylsulphate. Under these conditions, and with a potential of 1.1 V (positive) at the glassy carbon working electrode, it is demonstrated that picogram amounts of noradrenaline, dopamine, 5-hydroxytryptamine, tryptophan and 5-hydroxyindole acetic acid can be determined in tissue extracts of rat brain.