Chromatography Techniques

Major Chromatographic Techniques

The chromatography technique is one of the most powerful methods for separating a sample, such as a synthesized mixture or a biological crude extract, into its single components. The chromatography separation technique is based on substances partitioning between two phases: a stationary phase with a large surface and a mobile phase which moves through the stationary phase.

The most frequently used types of chromatography are gas or liquid chromatography. The difference is related to the physical state of the mobile phase in column chromatography. In gas chromatography, the mobile phase is a gas which transports the sample through a solid stationary phase, whereas in liquid chromatography the mobile phase is a solvent. The interaction of the compounds with the stationary phase, a process known as the mode of separation, is governed by differences in polarity, size, or specific binding affinities.