Binding Affinity
Also known as: affinity · receptor affinity · Kd
How tightly a molecule binds its target receptor — a key measure of how potent and selective a compound is.
Binding affinity describes the strength of the interaction between a molecule (a ligand) and its target, usually a receptor. Higher affinity means the molecule binds more tightly and at lower concentrations.
Affinity, together with whether the bound molecule actually activates the receptor, determines a compound’s potency and contributes to its selectivity. It is a core parameter in the pharmacology of any research peptide.
RELATED TERMS
Receptor / Agonist
A receptor is a cell’s signal-receiving protein; an agonist binds it and activates it, an antagonist blocks it.
Selectivity
How specifically a compound acts on its intended target and few others — the basis of a "clean" research effect.
Potency (Pharmacology)
The amount of a compound needed to produce a given effect — a more potent compound works at a lower dose.
Efficacy
The maximum effect a compound can produce once bound — distinct from potency, which is the dose needed to get there.
Analog
A peptide deliberately modified from a natural sequence to improve stability, selectivity or potency.
Educational content, not medical advice. All products supplied for research purposes only — not for human consumption.