Basic Principle of Chromatographic Separation
It is known that there are two phases in the chromatography, one phase is stationary, we call it the stationary phase, and the other phase flows through the stationary phase, which we call the mobile phase.
The principle of separation of chromatography is to separate the various substances to be separated in the two phases, such as the partition coefficient, adsorption capacity.
An external force is used to pass the mobile phase (gas, liquid) containing the sample through a surface of the stationary phase that is fixed in the column or on the plate and is incompatible with the flow. As the mixture carried in the mobile phase flows through the stationary phase, the components of the mixture interact with the stationary phase.
Due to the difference in properties and structure of the components in the mixture, the magnitude and strength of the force generated between the stationary phase and the stationary phase are different.
As the mobile phase moves, the mixture undergoes repeated distribution and balance between the two phases, The components are retained by the stationary phase for a different period of time, thereby flowing out of the stationary phase in a certain order. In combination with an appropriate post-column detection method, the separation and detection of each component in the mixture are achieved.