Understanding Thin layer Chromatography
Thin layer chromatography is a widely used form of chromatography. This type of chromatography mainly finds use in the separation process of non-volatile mixtures. Thin-layer chromatography consists of both a stationary phase as well as a mobile phase. The stationary phase is usually an adsorbent like Silica Gel, Aluminium Oxide or Cellulose. The thin-layer chromatography process works by the molecular adsorbent like Silica Gel absorbing the different components of the mixture, which has to be separated, at different levels. The adsorbents for thin-layer chromatography are always decided in such a manner that they will quicken as well as improve the separation as well as the subsequent purification process.
Thin-layer chromatography works by applying the sample on the plate. After that, the solvent or mobile phase is passed through the plate using capillary action. Different constituents move apart at different levels of the thin-layer chromatography plate and thus the separation process is complete.
Role of Silica Gel in Thin-layer Chromatography
As mentioned earlier, Silica Gel has a very important role to play in the thin-layer chromatography process. The reasons why out of all the adsorbents for thin layer chromatography, Silica Gel is the most preferred is very clear. Silica Gel has calcium sulfate as a binder and this makes it the best adsorbent available in the market. Silica Gel is well-known for its top-notch separation qualities and works as an excellent separation tool in the thin-layer chromatography process. When the Silica Gel adsorbent is placed on top of the thin-layer chromatography plate then it will speed up the separation and subsequently purification process.
With Silica Gel being the stationary phase, it will require a mobile phase, which has completely different properties from the stationary phase. As Silica Gel is a highly polar substance, then for the mobile phase it is recommended one use non-polar substances like as heptane. The mobile phase is usually made as a mixture so changes can be made accordingly.
As an adsorbent for thin layer chromatography, Silica Gel has produced good results in the separation and purification of a wide range of substances like alkaloids, amino acids, oils and fats, vitamins, plant pigments, drugs and sugars.