Ligand Binding Assay (LBA) is a powerful experimental tool used to study the interaction between biomolecules, especially the binding between ligand and receptor. This analysis is based on the physical and chemical binding reactions between the labeled ligands and its specific receptors to measure some parameters such as ligand-receptor affinity, the number of binding sites, and the maximum binding capacity of the receptor, which mainly includes enzyme-linked immunosorbent assay (ELISA), electrochemiluminescence (ECL) assay and radioimmunoassay (RAI).