Ni²⁺-BSA Directional Coordination-Assisted Magnetic Molecularly Imprinted Microspheres with Enhanced Specific Rebinding to Target Proteins

Protein imprinting technology is of interest in drug delivery, biosensing, solid-phase extraction, and so forth. However, the efficient recognition and separation of proteins have remained challenging to date. Toward this, under the assistance of Ni²⁺-bovine serum albumin (BSA) directional coordination strategy, magnetic BSA-imprinted materials had been synthesized via dopamine self-polymerization on hollow Fe₃O₄@mSiO₂ microspheres (mSiO₂ referred as mesoporous silica). The well-defined imprinted microspheres possessed more satisfactory adsorption capacity (266.99 mg/g), enhanced imprinting factor (5.45), and fast adsorption saturation kinetics (40 min) for BSA, superior to many previous reports. Benefiting from the coordinate interaction between Ni²⁺ and BSA, these fabricated microspheres exhibited excellent specificity not only in individual and competitive protein rebinding samples but also in bovine serum. Combined with the directional coordination method, the magnetic-imprinted composite materials to selectively capture target proteins could provide promising potential in applications.