A new mesoporous micelle-templated silica route for enzyme encapsulation

A new mesoporous micelle-templated silica (MTS) route for enzyme encapsulation is presented. The pore structure is given by a new association of lecithin (double chain surfactant) and dodecylamine as cosurfactant. To enhance and to well protect the enzyme activity, lactose was loaded in the synthesis. The mixed-micelles give after the addition of tetraethyl orthosilicate a well-ordered mesoporous material with a spongelike rigid structure stable after calcination at 550 degrees C. The size of the pores lies between 30 and 40 A, matching well with the size of the lipases. The activity of this heterogeneous catalyst was tested in the hydrolysis of the ethylthiodecanoate. These new biocatalysts were very active, more than hydrophobic sol-gel materials and commercially available sol-gel encapsulated lipase. This new MTS synthesis route allows one to encapsulate in one-step various enzymes, even those that are very fragile.