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Hill equation

Description

In biochemistry, the binding of a ligand to a macromolecule is often enhanced if there are already other ligands present on the same macromolecule (this is known as cooperative binding). The Hill coefficient provides a way to quantify this effect.
It describes the fraction of the macromolecule saturated by ligand as a function of the ligand concentration

Related formulas

Variables

θFraction of the ligand-binding sites on the receptor protein which are occupied by the ligand. (dimensionless)
KALigand concentration occupying half of the binding sites ( the microscopic dissociation constant) (dimensionless)
LFree (unbound) ligand concentration (dimensionless)
n Hill coefficient, depending on the context in which the Hill equation is being used (dimensionless)