Enzyme encapsulation using highly ordered mesoporous silica monoliths

Lipase encapsulation in 12 highly ordered mesoporous silica monoliths (HOMs) with different pore diameters (3-8 nm) and pore structures (2D and 3D mesostructures) was successfully achieved without leaching of the enzyme from the enzyme-HOM composite. The amount of lipase adsorbed on the HOMs was dependent on the pore diameter and pore structure. The 3D mesostructures had better enzyme adsorption capability than did the 2D mesostructures. Reaction kinetics showed that the lipase-HOM composites maintained high enzymatic activity during the hydrolysis of a triglyceride (80-85 of the activity of the free enzyme). Moreover, the thermal stability of the composites was greater than that of the free enzyme. These results strongly demonstrated the ability of HOM-n monoliths to act as supports for the stable immobilization of enzymes, with minimal loss of enzymatic activity.