Tailored zwitterionic polyhedral oligomeric silsesquioxane-chitosan-MXene hybrid framework for efficient immunoglobulin G separation.

Herein, a zwitterionic hybridization approach is engineered to develop a functional hybrid framework (MPC) for the efficient separation of immunoglobulin G (IgG). The in-situ polymerization of octa-carboxyl polyhedral oligomeric silsesquioxane (OCPOSS)-chitosan polymer on Ti3C2Tx MXene effectually enables the formation of local zwitterionic hydrophilic microregions in MPC, and meanwhile actuates its affinity ability and recognition selectivity toward IgG. When 1 mg of MPC serves as adsorbent to treat IgG solution (100 mg L-1, 1 mL), an adsorption efficiency of approximately 99.0 % is facilely reached. Superior adsorption performance of MPC is well demonstrated by satisfactory enrichment factor (119.3) and high binding capacity (866.4 mg g-1). MPC is further employed for the separation of IgG from complex biological samples, achieving a protein purity of 97.9 %. Experimental characterization and molecular docking simulation successfully affirm the prominent role of multiple components in MPC in the collaborative contribution to the selective affinity separation of IgG. This study not only affords a highly efficient pretreatment platform for specific biomarker detection and antibody purification, but also illuminates the huge prospects of zwitterionic MXene-based frameworks in the field of proteomics research.