The term “elution” refers to

In molecular biology, the term "elution" refers to the process of removing a substance from a solid support, such as an agarose gel, using a solvent. In the context of DNA analysis, elution typically refers to the process of extracting a purified DNA fragment from an agarose gel after it has been separated by electrophoresis.

After electrophoresis, the DNA fragments are visualized using a staining agent such as ethidium bromide, and the fragment of interest is cut out of the gel using a razor blade or other tool. The fragment is then extracted from the gel piece using a solvent such as TE buffer or water through a process known as elution.