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The chromatographic plate is formed by covering a layer of adsorbent on the substrate (or absorbing the carrier of the fixed phase), which can be directly used for the qualitative or quantitative analysis of various types of organic materials. It is widely used in medicine, Chinese herbal medicine, organic chemical products and food. From the coating material, the chromatography plate has a positive phase silicone plate, reversed phase silica plate, cellulose plate, aluminum oxide plate; From the back material, can be divided into glass plate, aluminum plate, plastic plate.