Vinyl sulfone-amino-alkyl supports: heterofunctional matrixes to prevent enzyme release and stabilize lipases via covalent immobilization.

New trifunctional supports were prepared (amino-octyl-vinyl sulfone (VS)- and amino-hexyl-VS-agarose) and compared to octyl-VS-agarose. They were utilized to immobilize the lipases A and B from Candida antarctica (CALA and CALB). After incubation to generate some enzyme-support bonds and blocking with different nucleophiles, SDS-PAGE analyses showed that all enzyme molecules become covalently immobilized on the support. In all VS biocatalysts, the blocking reagent presented a great effect in the properties of enzymes. The best blocking agents promoted a significant enzyme stabilization compared to the enzyme stability using the amino-alkyl-agarose supports, higher than that using octyl-VS-agarose supports, although these remained the most stable ones in most cases, as the octyl-biocatalysts were significantly more stable than the enzyme immobilized on amino-alkyl-support. Enzyme activities and specificities could be also greatly tuned by the immobilization in the new trifunctional supports, with enzyme activities in many instances enhancing that of the best non-covalently immobilized enzyme. That way, the results on this paper show that the properties of the enzymes when immobilized on these new trifunctional supports may be significantly tuned by the nature of the acyl chain in the support and the nature of the reagent used to block the reactivity of the remaining VS groups.