“Induced fit” recognition of proteins by surface imprinted silica with “soft” recognition sites

Molecular imprinting is a useful method to make enzyme mimics for protein recognition. Classic protein imprinting involves entrapping proteins within polysiloxane or polyacrylamide, but due to the rigidity of the recognition sites and the limited interaction between proteins and small molecule monomers, they often have unsatisfactory capacity, poor reproducibility and low specificity. In this report, “soft” and flexible recognition sites that can allow “induced fit” of the target proteins were created by a novel surface imprinting technique. When about 25% of the template proteins were removed, the unremoved proteins created “soft” and flexible loops that can lock into place upon protein rebinding, which provides additional favorable interactions between the rebind proteins and the imprinted sites. The adsorption capacity of the surface imprinted silica is 24.8×10−7 mol/g. The “soft” recognition sites can distinguish target hemoglobin from other proteins such as bovine serum albumin, Cytochrome C and RNase A.