THE PHOTOGRAPHIC RECORDING OF PAPER CHROMATOGRAMS OF CARBOHYDRATES AND A NEW SPRAY REAGENT

Abstract

When dry, the paper chromatogram is laid on the emulsion side of a piece of photographic paper and the 2 sheets are then stretched over a gently curved surface. The photographic paper is now exposed by holding a small UV source, e.g., a Mineralight, about 12 in. above the paper for 1 or 2 secs. The photographic paper is then processed in the normal way. The photographic print indicates size and exact shape of the spots which facilitates Rf measurements and permits rough quantitative estimations. Often spots will show up under UV illumination, which would not have been rendered visible by the ordinary technique. A new reagent was created, aniline hydrogen malonate. Decidedly superior to any other reagent used for the simple sugars, especially dissolved in glacial acetic acid (2%).