Paper Chromatography

Let us start with an irrelevant yet simple and similar example of coloured and structured marbles. Say, you have three coloured marbles with you, all shuffled up in a bag. Now, you want to separate these marbles based on their colour. How are we going to do this? Yes, you are going to make three slots of marbles based on their colour and separate the marbles into their respective colour slot. Now, think of these marbles as a chemical component, they are all mixed. You want to separate them. How can we do that? There comes Paper Chromatography in your rescue. This process separates these components, not based on colour but the distinct migration rates of the same. 

To understand the concept of Paper Chromatography or just Chromatography, we must have an understanding of the basic meaning of Migration- in the field of Chemistry. We know the meaning of Migration- that is, moving from one region to another. In the field of chemistry, the meaning of Migration is quite similar to that of the general meaning. Migration is the intermolecular movement of one or more atoms during the period of molecular rearrangement. It is the change in the position of an atom in a chemical component. 

Now, let us briefly understand what Paper Chromatography is. 

Paper Chromatography

In 1943, Synge and Martin came up with Paper Chromatography. It is one of the most important and powerful analytical tools that use the tiniest amount of material of a component. In addition to being a powerful tool, it is also an inexpensive method that helps in separating the liquefied chemical matters concerning the sheet of paper. This method helps make a distinction and divide singular components from the chemical components. This method is used in teaching TLC or any other Chromatography. 

There are various uses of this method in the field of Chemistry. It is used in the pharmaceutical industry for checking its purity and relevance. The cosmetics that we use in our daily lives are inspected with the help of this method. Many times, this method is used for the detection of contamination in foods and drinks, drugs, and dopes in living beings. There are many other applications of Paper Chromatography in our lives. 

Paper Chromatography can be of types, too. These types include Ascending, Descending, Ascending-Descending, Two Dimensional, and Circular Paper Chromatography. Let us discuss these types briefly:

• Descending: In this type of Paper Chromatography, the migration of the solvent is downward mainly because of gravitational and capillary pull. 
• Ascending: In this type of Paper Chromatography, the migration of the solvent is upwards.
• Ascending-Descending: In this type of Paper Chromatography, the migration is bi-directional after a certain point. Initially, the solvent starts migrating upwards and gradually travels downwards. 
• Two-Dimensional: In this type of Paper Chromatography, components having the same ratio will be resolved through two-dimensional paper chromatography.
• Circular: In this type of Paper Chromatography, the solvent migrates into the centre of the circular filter paper. 

Now that we know the meaning, uses, and types of Paper Chromatography. Let us move to the Principle of Paper Chromatography.  

Principle

Before moving to the principle of Paper Chromatography, we must know that Paper Chromatography has two phases. These phases are the Mobile phase and the Stationary Phase. The mobile or movable phase is the gas and the stationary phase is a paper. This paper in Paper Chromatography is made of Cellulose. This paper is hung into a concoction of solvents, which act as a mobile phase. The component mixture migrates along with the Mobile phase and travels through the Stationary phase- while separating based on the degree of adhesion of each component in the mixture. 

All different types of Chromatography follow a similar or same principle. One of the principles that are involved is widely known as Partition Chromatography. According to this principle, the components are partitioned according to the liquid phases. One of the liquid phases is the Mobile phase which moves across the paper and the other phase involves water which holds itself in the filter paper pores. 

Another principle involved is Absorption Chromatography which comes in between the liquid and solid phases. According to this principle, the mobile phase is the liquid phase and the stationary phase involves the solid phase. 

One of the most commonly used principles of Paper Chromatography is Partition Chromatography. We can also say that Paper Chromatography is an example of Partition Chromatography. 

Conclusion

For understanding the concept of Paper Chromatography, we must have an understanding of the basic meaning of Migration- in the field of Chemistry. In the field of chemistry, Migration is the intermolecular movement of one or more atoms during the period of molecular rearrangement. Paper Chromatography is one of the most important and powerful analytical tools and an inexpensive method. This method helps make a distinction and divide singular components from the chemical components. There are two phases of Paper Chromatography. These two phases are the Mobile phase and the Stationary Phase. All different types of Chromatography follow a similar or same principle. Principles involved in Paper Chromatography are the Partition and Adsorption Chromatography.