Preparation of Highly Ordered Mesoporous Silica Materials and Application as Enzyme Supports

摘要

A globular-enzyme, horseradish peroxidase(HRP), was adsorbed in the manner of single immersion method on the silica mesoporous materials, FSM-16, MCM-41 and SBA-15 with various pore diameters from 2.7 to 9. 2nm and their enzymatic activity in an organic solvent and the thermal stability were studied. FSM-16 and MCM-41 showed larger amount of adsorption of HRP than SBA-15 or silica gel, when the pore sizes were larger than the spherical molecular diameter of HRP (ca. 4.6nm) . The large amounts of adsorption capacity were attributed to the anionic surface characteristics of FSM-16 and MCM-41, which were suggested by larger adsorption capacity of cationic pigment than anionic pigment. The immobilized HRP on FSM-16 and MCM-41 with pore diameter 5.0nm showed the highest enzymatic activity in an organic toluene and thermal stability in aqueous solution at the temperature of 70℃ . The immobilized enzymes on the other mesoporous materials including large or small pore sized FSM-16, MCM-41 and SBA-15 showed lower enzymatic activity in an organic solvent and the thermal stability. The anionic surface character and size fitting between pore sizes and the molecular diameter of HRP was important to realize the high enzymatic activity in organic solvent and thermal stability.