Chromatography Uses

Chromatography is a laboratory process that occurs in several steps and is used to separate mixtures of various chemicals into their individual components. The governing principle of chromatography is that different chemicals in a mixture have different degrees of dissolving in a liquid or sticking to a solid surface. In other words, chromatography can identify a chemical and separate it from a dense mixture of other chemicals and show it on a surface.

Various chemicals in a mixture have different sticking ability on a surface. By varying this process in many ways, the chromatography technique can be used to separate any amount of quantities ranging from micrograms (in laboratories) to tons (in chemical plants). There are various chromatography procedures that have become popular since the invention of chromatography by Russian botanist, Mikhail Semyonovich Tsvet, in 1901.

In the chromatography processes, a stream of liquid, that is called mobile phase, is made to flow through a tube known as column, and it is packed with porous solid material, called the stationary phase. The sample of the mixture that is to be analyzed is sent through the mobile phase and as the mixture proceeds in the tube, the compounds are separated. Chromatography is preferred over many other techniques as it doesn't cause any molecular changes in the composition of the chemicals involved.

Uses of Chromatography
Chromatography has evolved to be one of the most widely used chemical techniques to separate particles and contaminates in chemical plants. For example, in the chemical industries, pesticides and insecticides like DDT in the groundwater and PCBs (Polychlorinated biphenyls) are removed by the process of chromatography. As a major testing tool, chromatography is used by government agencies to separate toxic materials from the drinking water and also to monitor air quality. Chromatography is used by pharmaceutical companies to prepare large amounts of pure materials that are further required in making medicines. Also, it is used to check the presence of any contamination in the manufactured compounds.

In the field of organic chemistry and pharmacy, chiral compounds are very close to each other in terms of atomic or molecular weight, element composition, and the physical properties. However, they exist in two different forms, called the enantiomers and optical isomers. Both these compounds though may appear to be same, have very different chemical properties. So, in pharmacy, chromatography becomes crucial to analyze the exact chiral compound so that correct medicines can be manufactured. For instance, a compound called thalidomide has two optical isomers and one of the isomers can cause birth defect if a pregnant women consumes it in early stages of pregnancy. So, it is important to carefully separate the isomers. Chromatography is used as a technique to separate the additives, vitamins, preservatives, proteins and amino acids. Some other uses are in the detection of drugs or medications in the urine and the separation of traces of chemicals in the case of fire in houses or buildings. It is also very popular in forensic science for investigative purposes.

Chromatography technology has gained immense industrial popularity in the past few decades as it can separate chemicals that just differ even in their atomic orientations in space.
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