Dual-recognition membrane Adsorbers combining hydrophobic charge-induction chromatography with surface imprinting via multicomponent reaction

The combination of mixed-mode chromatography (MMC) and molecular imprinting technology (MIT) has been proven to be successful for protein separation, but suffered from cumbersome material preparation and limited performance. In this work, a new modification method marrying atom transfer radical polymerization (ATRP) and multicomponent reaction was proposed to simplify the preparation process. Using regenerated cellulose (RC) membrane as the substrate, immunoglobulin G (IgG) as the template protein and tryptamine as the ligand, a dual-recognition membrane adsorbers (MIM) was prepared by mild Ugi four-component reaction (Ugi-4CR) and surface initiated ATRP. Control the ATRP time is the key for surface imprinting. The static IgG uptake and selectivity of UGI membrane were 45 mg/mL and 1.8, respectively, while those of MIM-0.5 were 42.5 mg/mL and 14, indicating that the introduction of molecular imprinting technology significantly improved the selectivity of the membrane to IgG. The MIM-0.5 membrane retains the pH-dependent and salt-tolerant of HCIC. The dynamic flow-through results showed that the MIM-0.5 membrane could effectively separate IgG from IgG/BSA mixed solution with the purity of 88% and retained its bioactivity. This work demonstrated the feasibility of bonding HCIC and MIT to the membrane surface by Ugi-4CR and ATRP.