Formation of a mesoporous bioreactor based on SBA-15 and porcine pancreatic lipase by chemical modification following the uptake of enzymes

Taking advantages of the nano-sized pore diameter, large surface area, and high pore volume of SBA-15 as a support, porcine pancreatic lipase (PPL) was immobilized in the mesoporous channels of the support through physical adsorption. The chemical modification was then performed to reduce the pore openings of SBA-15 uptaking PPL, in order to prevent the leaching of PPL. Two procedures were applied to shrink the pore size of SBA-15 entrapping PPL. The first procedure involves the surface grafting of the SBA-15 entrapping enzyme with 3-(trimethoxysilyl)propyl methacrylate (H2CC(CH3)CO2(CH2)3Si (OCH3)3, abbreviated as PMA). The second procedure involves the in situ polymerization of the pendant vinyl groups with free PMA, following the silylation. The assay of enzyme activity shows that the reduction in pore size by chemical modification prevents the PPL leaching as expected. The formation and structure of the resulting inorganic–organic hybrid materials, which can be regarded and used as a mesoporous bioreactor, were investigated in this paper.