Covalent Design of Cell Membrane Stationary Phase with Enhanced Stability for Fast Screening P-Glycoprotein Inhibitors.

Cell membrane chromatography (CMC) has been widely used for characterizing the interaction between drugs and membrane receptors to screen target components from herbal medicines. However, the column life, stability, and the efficiency cannot meet the needs of high-throughput screening purpose. In this study, a P-glycoprotein immobilized cell membrane stationary phase (P-gp/CMSP) was prepared with a simple and mild two-step aldehyde modification, realizing the covalent bonding between cell membrane and stationary phase. The column life and stability were significantly enhanced compared with the unmodified columns. The P-gp/CMC column was equipped into a comprehensive 2D P-gp/CMC/Capcell-C18/TOFMS system, which actualizes the automated and high-throughput analytical process and rapid identification of complex chemical samples with no data loss. Five compounds with significant retention were screened out and unambiguously identified by the comprehensive 2D analytical system. Baicalin was confirmed as a P-gp inhibitor with ATP depletion inhibition ratio of 83.4%. Moreover, the reversal index of baicalin on DOX significantly increased to 11.13 when its concentration reached 25 µM, revealing that baicalin could effectively reverse the MDR cell model induced by DOX. The integrated system is a practical drug discovery platform and could be applied to other transmembrane protein models.