Water-in-ionic liquid microemulsion-based organogels as novel matrices for enzyme immobilization.

The use of water-in-ionic liquid microemulsion-based organogels (w/IL MBGs) as novel supports for the immobilization of lipase B from Candida antarctica and lipase from Chromobacterium viscosum was investigated. These novel lipase-containing w/IL MBGs can be effectively used as solid phase biocatalysts in various polar and non-polar organic solvents or ILs, exhibiting up to 4.4-fold higher esterification activity compared to water-in-oil microemulsion-based organogels. The immobilized lipases retain their activity for several hours at 70 degrees C, while their half life time is up to 25-fold higher compared to that observed in w/IL microemulsions. Fourier-transform infrared spectroscopy data indicate that immobilized lipases adopt a more rigid structure, referring to the structure in aqueous solution, which is in correlation with their enhanced catalytic behavior observed.