Investigation on the interactions between a drug and receptor can provide key insights into the molecular basis and mechanism of the drug.β2-adrenoceptor (β2-AR) is a member of a family of seven transmembrane proteins coupled to G-proteins.G-protein-coupled receptors represent the largest superfamily of all receptor types, and account for the major proportion of current drug targets.High-performance affinity chromatography has been shown to be a useful method to examine the interactions of drugs with β2-AR.