A New Method for the Detection of Peptides and Similar Compounds on Paper Chromatograms

Abstract

SINCE the first introduction¹ of paper chromatography for the separation and identification of amino-acids and peptides, ninhydrin has been used almost exclusively as the spraying reagent to reveal the positions of the spots, although some use has been made of ultra-violet fluorescence² and of spraying with potassium permanganate³ and specific reagents for individual amino-acids⁴. Ninhydrin, however, has two serious limitations: it does not react with cyclic peptides or with acylated amino-acids or peptides, while with peptides, since only the terminal amino-group enters into the reaction, the colour developed with a given amount of material decreases with increasing molecular weight.