The influence of hydrochloric acid on the chromatographic behaviour of sympathomimetic catecholamines

The behaviour of three catecholamines on paper chromatograms is shown to be markedly influenced by hydrochloric acid. Double spot formation exhibited by noradrenaline acid tartrate, for example, results from the use of hydrochloric acid in the developing solvent, but the formation of the second spot is prevented when the amine is applied to the paper from solution in dilute hydrochloric acid. Retention of amine at the application area and additional multiple spot phenomena are exhibited by all of the three amines investigated when chromatographed from concentrated hydrochloric acid. The significance of these and related observations is discussed in relation to the use of hydrochloric acid during the separation of catecholamines from biological tissues and fluids.