Rapid analysis of interaction between six drugs and β 2 ‐adrenergic receptor by injection amount‐dependent method

Drug–protein interaction analysis has become a considerable topic in life science which includes clarifying protein functions, explaining drug action mechanisms and uncovering novel drug candidates. This work was to determine the association constants ( K A ) of six drugs to β 2 ‐adrenergic receptor by injection amount‐dependent method using stationary phase containing the immobilized receptor. The values of K A were calculated to be (25.85 ± 0.035) × 10 4   m −1 for clorprenaline, (42.51 ± 0.054) × 10 4   m −1 for clenbuterol, (6.67 ± 0.008) × 10 4   m −1 for terbutaline, (33.99 ± 0.025) × 10 4   m −1 for tulobuterol, (7.59 ± 0.011) × 10 4   m −1 for salbutamol and (78.52 ± 0.087) × 10 4   m −1 for bambuterol. This rank order agreed well with the data determined by zonal elution, frontal analysis and nonlinear chromatography, even using different batches of β 2 ‐AR column. A good correlation was found between the association constants by the current method and radio‐ligand binding assay. Our data indicates that the injection amount‐dependent method is a powerful alternative for rapid analysis of ligand–receptor interactions.