Stationary phase

Stationary phase is a term used in chromatography to refer to the phase that does not move in the process. It can be a solid or a liquid supported on a solid. The mobile phase or the eluent, in the course of the run, transports the analytes. The physical and chemical properties of the stationary phase play a significant role in the separation process of the analytes.

Overview

In chromatography, the sample mixture is introduced into the system in a discrete small zone (the mobile phase), then transported through the system by the mobile phase. The stationary phase impedes the passage of the components of the sample. The components are, therefore, separated based on their differing affinities for the stationary phase, the mobile phase, or both.

Types of Stationary Phases

There are several types of stationary phases used in chromatography, including:

• Liquid stationary phase: This is used in liquid chromatography and is usually coated onto a solid support. The liquid can be any number of solvents, depending on the type of chromatography being performed.

• Solid stationary phase: This is used in gas chromatography. The solid can be any number of materials, including silica or alumina.

• Bonded phase: This is a stationary phase that is covalently bonded to the support particles or to the inside wall of the column tubing.

Applications

The stationary phase in chromatography has a wide range of applications in various fields such as:

• Pharmaceutical industry: It is used for the separation and identification of chemical compounds in the production of drugs.

• Environmental science: It is used for the analysis of pollutant substances in the environment.

• Forensic science: It is used for the identification of substances in crime scene samples.

See Also

• Chromatography
• Mobile phase
• Analyte
• Eluent