Surfactant-lipase complexes immobilized in PEG microspheres

A surfactant-lipase complex is immobilized in a polyethylene glycol (PEG) microsphere to realize the repeated use of the enzyme complex in organic solvents. The preparation is based on the emulsion-drying method. The enzyme complex dissolving in an internal oil phase is entrapped into the polymer matrix during lyophilization. The immobilized lipase complex exhibits a high catalytic activity comparable to that of the free lipase complex to an esterification reaction in nonaqueous media, while the powder lipase shows no enzymatic activity. The PEG microspheres containing the lipase complex can be readily recovered by facile filtration. The high activity was completely preserved after re-using ten times.