Establishment and verification of assay method for the receptor binding affinity of a PEGylated Exendin-4 analogue

The assay method of GLP-1 receptor binding affinity for a long-acting hypoglycemic peptide—PEgylated Exendin-4 analogue(PE)was optimized and established based on the luciferase reporter gene approach. CHO-GLP-1R-CRE-Luc⁺ cells were previously constructed in our lab followed by the verification of methodology. This assay method showed good specificity and robustness as well as high accuracy and precision when PE was incubated with the cell for 4 h, the luminescent substrate reacted with cell lysates for 15 min and the concentration for PE ranged 5. 7×10^-3-1. 5×10³ nmol/L, on which condition this developed method is in accordance with General Principles of Analytical Method Validation Techniques for Biological Products Quality Control. This study also lays the foundations for rapid evaluation and screening of GLP-1 receptor agonist drugs.