Immobilization of enzyme-encapsulated nanoporous material in a microreactor and reaction analysis

A microreactor containing lipase-nanoporous material composites was developed and employed in the hydrolysis reaction of a triglyceride. Lipase used as a model enzyme was encapsulated in two types of folded-sheet mesoporous silicas, FSM4 and FSM7, with pore diameters of approximately 4 and 7 nm, respectively. Direct microspectroscopic analysis of fluorescently labeled lipase immobilized in the FSM-containing microreactor revealed that the enzyme did not leach into the solution during the hydrolysis of the triglyceride, because of the stable immobilization of the enzyme. The lipase-FSM composites contained in the microreactor displayed higher enzymatic activity than those in a batch experiment. These results demonstrate that the enzyme microreactor using mesoporous silica was successfully constructed and that it exhibited high enzyme reactivities.