*6.4.1 Column chromatography*

Chromatography on a column separates and purifies phytochemicals on a laboratory and industrial scale without the use of complicated technology. The "eluent" is the liquid employed as the mobile phase, and the stationary phase is usually a solid or a liquid. The sample solution is supplied to a porous stationary phase, and the mobile phase is delivered at a greater pressure via the column, causing separation depending on the solute's affinity for the stationary phase. The development of HPLC (High-Performance Liquid Chromatography) was aided by the need for a higher degree of separation and faster analysis, which was met by refining the stationary phase packing material to a size of 3–10 m and eluent delivery via a high-pressure pump. Despite its extensive and time-consuming nature, commercial use of column chromatography is comparable to that of other techniques. The advantages of column chromatography include efficient sample handling regardless of the number or nature of the samples, the availability of a wide range of adsorbents, the selection and recyclization of a large solvent system, improved purity of the product, and minimal space requirements. Column chromatography has a few disadvantages, including the use of a large amount of mobile phase, compared to other techniques it is a complicated technique, time consumption, the requirement for an expert, and a greater cost of identifying the separated product.
