Synthesis and characterization of liquid chromatographic columns containing the immobilized ligand binding domain of the estrogen related receptor α and estrogen related receptor γ

The ligand binding domains of the estrogen related receptors, ERRα and ERRγ were covalently immobilized onto the surface of an aminopropyl silica liquid chromatography stationary phase to create the ERRα-silica and ERRγ-silica columns and onto the surface of open tubular capillaries to create the ERRα-OT and ERRγ-OT columns. The ERR-silica and ERR-OT columns were characterized using frontal chromatographic techniques with diethylstibesterol and the binding affinities, Kd values, to the immobilized receptors were consistent with the values obtained by a radioligand binding assay. The ERRγ-silica column was also characterized using non-linear chromatographic techniques using a series of tamoxifen derivatives. The relative Kd values obtained for the derivatives were consistent with the relative ability of the compounds to inhibit the cellular proliferation of the human-derived T98G glioma cell line, expressed as IC50 values. The results indicate that the columns containing immobilized ERRα and ERRγ can be created and used to characterize the binding of compounds to the immobilized receptors and that the relative retention of compounds on these columns reflects the magnitude of their inhibitory activity.