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Liquid chromatography (LC) is an instrumental technique for separating components of a mixture. Typically, samples are injected into a mobile phase and is carried through an analytical column where components are separated based upon their relative affinities for a liquid mobile phase and the solid stationary phase of the column.   Depending on the composition of the mobile phase and column packing material a variety of samples can be analyzed using this method.  As this technique requires only that the sample be soluble, it is often used for non-volatile analytes. It is frequently used in the analysis of environmental, biological, and pharmaceutical samples.  It is capable of detecting analytes ranging in size from ions to large polymers and biological molecules including proteins.  Other techniques such as ion chromatography (IC), size exclusion chromatography (SEC), gel permeation chromatography (GPC), and gel filtration chromatography are specialty forms of LC.

LC may be combined with a number of different detectors. Most common are ultraviolet-visible, fluorescence, and mass spectrometric detectors.  More specific detectors, including electrochemical, evaporative light scattering, and refractive index detectors are available for specialty analysis. 

LC instrumentation is most commonly found in benchtop models. This reflects the component nature of the instrumentation which often includes solvent degassers, autosamplers, and thermostatted column compartments in addition to the required solvent pumps, sample injector ports, and detectors. 

LC is a very mature analytical technique and is used widely in industry and environmental applications.  The cost of instrumentation is widely variant and is largely dependent upon the type of detector selected for the system.