Abstract
Compounds related to isonicotinic acid hydrazide and their hydrazones show tailing in thin-layer chromatography when using ordinary silica gel. It is considered that this tailing is due to formation of chelate compounds during development by reacting with trace metals in the adsorbent but since the stability of such metal chelates is far smaller than that of organic analytical reagents, this tailing is only weak. In order to prevent this tailing, adsorbent was treated with EDTA and a good result was obtained. Detection of these compounds after development is made by Fe(III)-2, 2'-bipyridyl and by the citric acid reagent solution. Isonicotinic acid hydrazide was detected by the former reagent at above 0.5 μg. Examinations were also made on the separatory detection of related compounds.
