chelating agent

This term is primarily used in chemistry, medicine, and environmental science. It describes a specific type of ligand that "grabs" a metal ion like a claw, which is the literal meaning of the Greek root chele. The resulting complex is typically more stable than those formed by monodentate ligands.

In a medical context, these agents are used for chelation therapy to remove toxic heavy metals, such as lead or mercury, from the bloodstream. In industrial applications, they are used to soften water by sequestering calcium and magnesium ions to prevent scale buildup.