Chrominfo: Mobile Phase in TLC

The mobile phase is an important factor of each type of chromatographic separation as they move the sample through the stationary phase and separation occurs, it according to the affinity of the components towards the stationary phase.

Solute Characteristics:

The mobile phase is a source of mobility in thin layer chromatography, however more significantly it produces selectivity.

Selectivity:

The degree of interaction amongst solvent system components and analytes determine the degree of any resolution that will be attained. The strength of solvent is the factor determining mobility. By identifying the characteristics of an analyte it becomes easy to select which solvent to use during the search for the mobile phase that provides the desired separation.

Below are mentioned some general characteristics of mobile phase solvents in TLC.

If solvents stored in metal containers, it may be subject to unknown chemical reactions and decomposition and it can change the characteristics of the solvent.
Sometimes autoxidation happens by storage of solvent, particularly if the solvents store over long periods of time.
The impurities of the solvent can vary from batch to batch and these may interact with solvents and components.
Water content: This can vary generally, and is a common source of reproducible problems, as traces of water can cause drastic changes in the selectivity and strength of the solvent.
In chloroform the ethanol as a preservative often contains, and it has a high solvent strength can have effects on the separation.

Chrominfo

Pages

Wednesday, October 2, 2019

Mobile Phase in TLC

No comments:

Post a Comment