Co-immobilization of glucose oxidase and catalase on magnetic mesoporous bioactive glasses

Due to the biocompatibility and bioactivity, bioactive glasses is consider as a new type of carrier for enzymes immobilization. In this paper, the bioactive glasses was modified to be magnetic using the sol-gel approach and polyethylene glycol (PEG) and was used to immobilize glucose oxidase and catalase. Co-immobilization was much more better than individual immobilization of the two enzymes. The special activities and enzyme characterization were determined and the best medium was selected. Under the conditions of 0.4% glutaraldehyde, 1.5% moisture, and glucose oxidase: catalase of 1:2, the enzyme recovery of glucose oxidase reached 92.25%. In aqueous phase, the maximum enzyme recovery was only 72.18%. After 10 repeated use, the residue activities of the immobilized enzyme in organic solvent and aqueous phase were 67.30% and 44.33%, respectively.