Using open‐tubular capillary electrochromatography with part‐coating column for binding constants determination of β2‐adrenergic receptor with seven drugs

An open‐tubular capillary electrochromatography method has been developed for the determination of binding constants between β₂‐adrenergic receptor (β₂‐AR) and seven drugs. β₂‐AR was oriented immobilized onto one part of inner surface of capillary via microwave‐assisted technical synthesis. According to the linear relationship between coating length and the apparent mobility of analyte, the binding constant (K_b) can be obtained by related theories and equations. The order of K_b values between drugs such as adrenaline hydrochloride, norepinephrine bitartrate, and propranolol hydrochloride with β₂‐AR is well consistent with that reported in the literature. By the method, K_b values between four extracts of Radix Paeoniae Rubra and β₂‐AR were also successfully obtained. Subsequently, computer models were applied to interpret the CEC experiments. And the results proved to be in good agreement with the method. The work, herein, demonstrates the potential of the method in drug‐receptor affinity interactions evaluation and screening of lead compounds from natural sources.