Chromatography

This chapter studies chromatography, which is the collective term for a family of analytical techniques used to separate the components of mixtures of molecules for their identification and possible estimation of their concentrations in the original mixture. All chromatographic techniques are based on differences in the relative affinities of the molecules in a mixture of two different and immiscible phases, one of which is mobile and the other stationary. The basis of all forms of chromatography is the partition or distribution coefficient, which describes the way in which a substance distributes at equilibrium between two immiscible phases. Most types of chromatography are used in biomedical science laboratories to assist in analysing and purifying analytes from a variety of clinical samples. The chapter then looks at planar chromatography, column chromatography, high-performance liquid chromatography, and gas-liquid chromatography.