A colour reaction distinguishing between adrenaline and nor-adrenaline on paper chromatograms

IN recent studies we were concerned with the detection of traces of nor-adrenaline in preparations of adrenaline derived from natural sources. Colorimetric methods1,2 proved to be of limited value with low concentrations of nor-adrenaline; but excellent results were obtained with paper chromatography, using modifications of the methods described by James and others3,4. The adrenaline samples are dissolved in methanol containing a minimum quantity of hydrochloric acid, and then transferred to paper strips for descending chromatography, or to circular disks of filter paper for chromatography by Rutter's technique5. Water-saturated phenol is used as the developing solvent in an atmosphere of hydrochloric acid4. The paper chromatograms are then dried and sprayed with an appropriate colour reagent.