What does it mean to elute in chromatography?

In chromatography, the term "elute" specifically refers to the process of removing a substance from a solid or liquid medium using a solvent. This is a crucial part of the chromatography technique, where components of a mixture are separated as they pass through a stationary phase. The solvent, often called the mobile phase, carries the desired substance away from the stationary phase, allowing it to be collected and analyzed.

When a sample solution is applied to the chromatography system, different components interact with the stationary phase to varying degrees. As the solvent moves through, it "elutes" the compounds based on their affinities for the stationary phase versus the mobile phase. This selective removal is what facilitates the separation of mixtures into their individual components, making it a fundamental concept in the field of analytical chemistry and biosciences.