Term: mobile phase
https://doi.org/10.1351/goldbook.M03952

Definition:
A fluid which percolates through or along the stationary bed, in a definite direction. It may be a liquid (liquid chromatography) or a gas (gas chromatography) or a supercritical fluid (supercritical-fluid chromatography). In gas chromatography the expression carrier gas may be used for the mobile phase. In elution chromatography the expression 'eluent' is also used for the mobile phase.

Related Terms:
1) liquid chromatography (http://doi.org/10.1351/goldbook.L03578).
2) gas chromatography (http://doi.org/10.1351/goldbook.G02578).
3) supercritical-fluid chromatography (http://doi.org/10.1351/goldbook.S06139).
4) supercritical fluid (http://doi.org/10.1351/goldbook.S06138).
5) chromatography (http://doi.org/10.1351/goldbook.C01075).
6) carrier gas (http://doi.org/10.1351/goldbook.C00863).
7) elution chromatography (http://doi.org/10.1351/goldbook.E02046).
8) eluent (http://doi.org/10.1351/goldbook.E02040).

Source: Orange Book, 2nd ed., p. 97 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'mobile phase' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03952

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