Detection of some Precursors of Adrenaline by Paper Chromatography

Abstract

DURING studies on the biosynthesis of adrenaline, both para- and meta-hydroxyphenylethanolamine have been found to form noradrenaline following ultraviolet irradiation in the presence of air¹. Whereas the para compound has been identified in Octopus vulgaris², the meta compound has not hitherto been found occurring naturally. Their detection in biological materials is a major problem. With the aid of paper chromatography, using a solvent of butanol (4 vol.), glacial acetic acid (1 vol.) and water (5 vol.), we have found that the meta compound exhibits an intense violet fluorescence under ultra-violet light when the developing agent is a mixture of 9 vol. of a solution of either potassium ferricyanide or dichromate (0.66 per cent) and 1 vol. of formaldehyde (40 per cent), followed by exposure to heat (100° C.) for 5 min. As little as 0.5 µgm. (R_F value 0.56) can be identified by this test. Development with the p-nitraniline reagent³ results in a dark red spot (similar to that produced with the para compound), but this test is only sensitive to 5 µgm.