Research into the role of the catecholamines has often depended on the reliable determination of plasma catecholamine concentrations, which present a challenge since they are normally in the low pg/ml range. Most methods employ liquid chromatography, with variations in sample preparation, the separation mechanism, and detection. We tested a new approach to sample clean-up using boric acid gel instead of alumina. No advantage was found. We also compared cation-exchange separation with ion-pair chromatography. Several improvements are possible with the former, most notably greater precision, better specificity, and increased throughput.