Chromatography

BackgroundClinical tests often involve the use of one or more separation steps to isolate, enrich, or separate a target compound from other chemicals in the sample. Chromatography is one of the most common methods for achieving this type of separation. In this method, the components of a mixture are separated based on their differential interactions with two chemical or physical phases: a mobile phase and a stationary phase that is held in place by a supporting material. There are many forms of chromatography based on the different mobile phases, stationary phases, and supports that can be used in this method, which has led to a wide range of applications for this technique.ContentThis chapter describes the basic principles of chromatography and discusses various forms of this method that are used for chemical analysis or to prepare specimens for analysis by other techniques. The methods of gas chromatography and liquid chromatography are discussed, as well as the techniques of planar chromatography, supercritical fluid chromatography, and multidimensional separations. The mobile phases, stationary phases, and supports that are used in each of these methods are described. The instrumentation and detection schemes that are employed in these methods are also discussed.Biological fluids are complex mixtures of chemicals. This means that clinical tests for specific components in these fluids often involve the use of one or more separation steps to isolate, enrich, or separate the target compound of interest from other chemicals in the sample. Chromatography is one of the most common methods for achieving this type of separation. This chapter describes the basic principles of chromatography and discusses various forms of this method that are used for chemical analysis or to prepare specimens for analysis by other techniques.