Improved surface imprinting based on a simplified mass-transfer process for the selective extraction of IgG.

We wished to improve the unsatisfactory adsorption and elution efficiencies in conventional magnetic molecular imprinting technology. In this work, a reliable strategy to prepare magnetic molecularly imprinted nanoparticles (MMINs) with rapid rebinding and elution speed was introduced. To decrease the mass-transfer retention of the templates, glycoprotein immunoglobulin (Ig)G was pre-immobilized to form homogeneous and monostratified three-dimensionally imprinted cavities on the surface of magnetic carriers. To shorten the transfer route of the templates, the polymerizaiton process was controlled precisely to form well-defined molecularly imprinted polymer (MIP) films of thickness 12 nm. In this way, the effectiveness of the mass transfer of the templates was maximized, and the length of the transfer route was minimized. As a result, the prepared MMINs showed improved adsorption and elution efficiencies compared with the conventional magnetic molecularly imprinted polymers (MMIPs), and exhibited great selectivity towards the templates.