▎ 摘　　要

Currently, semiconductor nanoparticles known as quantum dots (QDs) have attracted interest in various application fields such as those requiring sensing properties, binding assays, and cellular imaging and are the very important in the acceleration of drug discovery due to their unique photophysical properties. Here, we applied graphene quantum dots (GQDs) for the binding assay of membrane progesterone re-ceptor alpha (mPR alpha), one of the probable membrane receptors that have potential in drug discovery applications. By coupling the amino groups of mPR alpha with GQDs, we prepared fluorogenic GQD-conjugated mPR alpha (GQD-mPR alpha). When mixed with a progesterone-BSA-fluorescein isothiocyanate con-jugate (P4-BSA-FITC) to check the ligand receptor binding activity of GQD-mPR alpha, fluorescence at 520 nm appeared. The fluorescence at 520 nm was reduced by the addition of free progesterone into the reaction mixture. GQD-coupled BSA (GQD-BSA) did not show a reduction in fluorescence at 520 nm. The results demonstrated the formation of a complex of GQD-mPR alpha and P4-BSA-FITC with ligand receptor binding. We established a ligand binding assay for membrane steroid receptors that is applicable for high-throughput assays. (C) 2022 Elsevier Inc. All rights reserved.