Tuning interfacial non-covalent interactions through biomimetic functionalization of inorganic surface: The case of lysozyme and mesocellular silica foam hybrids

The mesocellular silica foam (MCF) surface has been functionalized with –OH, –C3H6H, –C3H6NH2, –C3H6NHCONH2, and –C3H6COOH biomimetic groups. Thereby the non-covalent interaction between protein and support surface is generated and tailored in virtue of the surface modification and varied pH of adsorption medium. The adsorption kinetics, adsorption thermodynamics, protein distribution and adsorption reversibility have been discussed in relation to the surface–protein interfacial interactions and protein–protein lateral interactions. It is found that between lysozyme and MCF surfaces, the electrostatic force, hydrophobic interaction, π–π overlapping, and some hydrogen bonding are similarly effective driving forces for protein adsorption. But depending on the nature of interfacial interactions, the effects of protein–protein repulsion on the lysozyme adsorption are diversified. The biomimetic modification of inorganic support surface counteracts in part the inhibition effects of protein–protein repulsion on protein adsorption, thus favoring the adsorption capacity. The adsorption of lysozyme on MCF supports causes no visible loss of enzymatic activity.