Nano-silica particles enhanced adsorption and recognition of lysozyme on imprinted polymers gels

Molecular imprinting technology has a great potential to be used in protein separation and purification. In this work, lysozyme imprinted polyacrylamide gel was prepared with silica particles as a sacrificial template to generate macro-porosity for fast adsorption. The adsorption equilibrium time and adsorption capacity were 9 h and 56 mg/g respectively, which was 2 h less and 2.3-fold more than polymers without the sacrificial template. In order to test molecular imprinting polymers (MIPs)' selectivity, bovine serum albumin (BSA) was chosen as interferent for binary adsorption tests. In addition, the adsorption selectivity was further investigated using different molar ratios of lysozyme to BSA with fixed total concentration of proteins, as well as using various total concentrations of proteins with an equimolar ratio of lysozyme to BSA. It has been proven that the total concentration of proteins should be larger than 1.5×10^-7 mol/mL, when the molar ratio of BSA to Lyz is 1∶1, in order to effectively separate Lyz from the binary protein mixture. The macro-porous lysozyme molecularly imprinted polymers have less adsorption time, larger adsorption capacity, and better imprinting effect.