Polyamide Thin‐Layer Chromatography. III. A Modified Method of Preparation of Thin‐Layer and its Application to some Naturally Occurring Phenolic Substances

Abstract Some modifications on the preparation of thin‐layer were made. By using the modified thin layer, the time required for development was shortened to one to two hours. Temperature and humidity effects for the thin‐layer formation are discussed. Small plates with the dimension 5×5 cm were prepared for horizontal development for preliminary solvent and color tests. The crude extractives of leaves of six plants, comprising Evodia glauca Miq., Glycosmis cochinchinensis Pier, Clausena lumulata Hayata, Atalantia buxifolia Oliver, Pittosporum formosanum Hayata, and Murraya paniculata Jack., were investigated by polyamide thin‐layer chromatography. It was observed that the crude extractives gave satisfactory chromatogram.