But in this case, the solid is absorbed by a thin layer on a solid piece of glass or plastic. Thin layer chromatography is a solid-liquid absorbent chromatography, and its principles are like column chromatography. The practical method in this method, except for the preparation of plates, is very similar to that of paper chromatography. At the end of the process, the solvent evaporates from the plate and reveals and identifies the stains isolated by physical or chemical methods, in the manner used in paper chromatographs. If a more sophisticated device is used, descending or horizontal chromatography can be done, but these methods are less common. When the dried stain leaves the plate perpendicularly in a suitable reservoir so that the lower edge of it is immersed in the moving phase, material separation is carried out using upstream chromatography. Place a solution of the sample in a volatile solvent with a pipette or syringe on the screen. The plate is dried and heated at about 100, pre-set, activate it. It is also possible to prepare the layer using the method of spraying or dipping. Solid adsorbent in the form of fine powder with water, and sometimes with an escaping liquid, in the form of dough, and distributed by a commercial player or a simple home-grower or even by hand. Glass sheets are commonly used, but there are other methods. Initially, chromatographic plates are required, ie, the gravity is distributed as a thin layer of uniform thickness on an inert rigid support. The quaternary is often made up of cellulose, which is used to separate hydrophilic molecules such as carbon hydrates, amino acids, nucleic acid derivatives and minerals Thin Film Chromatography Mechanism

The particles on the layer should be large and compact and small. Thin-layer chromatography is a type of adsorption chromatography, in which thin-film plates are used and the position of the components on the plate is determined.

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