THIN LAYER CHROMATOGRAPHY

Chromatography is a separation method based on the different migration of solutes through a system of two diverse phases, one of which is mobile and the other stationary. Fluid entering the column or solvent that carries the analyte is ELUENT. 

Mobile phase leaving the column is ELUATE. Thin Layer Chromatography is one of the simplest , fastest, easiest and least expensive of several chromatographic technique used in qualitative and quantitative analysis to separate organic compounds and to test the purity of compounds. It is a form of liquid chromatography. It is a separation or identification of a mixture of components into individual components by using finely divided adsorbent solid/liquid spread over a glass plate and liquid as a mobile phase. TLC is advanced form of paper chromatography. In TLC , a solid support may be of plastic or silica of 0.25mm. Coating is very thin layer to resolve all mixtures of molecules from each other father and faster. If layer is thick than Mobile phase will be trapped and absorbed by stationary phase more often. 

• Take the TLC plate and draw the margins on both the ends. 
• Than place the samples on the starting margin with markings. 
• Suppose ,that  Mobile phase is non –polar than place the TLC plate in it. 
• Do not submerge the marked margin into the solvent. Through capillary action the sample will start moving towards the end margin. 
• Sample when will not interact with stationary phase specimen will move faster with solvent. When sample comes to the end margin take it out and let it dry. 
• After drying of TLC plate analyze the result under UV light. 
• Mark the spotted sample with pencil by making circle around it. 
• Now, measure the retention factor from the center of the circle drawn.

Rf =distance traveled by each spot / Total distance traveled by the solvent

Thin Layer Chromatography