Development of urease-chitosan membrane.

Urease was covalently immobilized on glutaraldehyde-pretreated chitosan membrane. The optimum immobilization conditions were determined with respect to glutaraldehyde pretreatment of membranes (concentration and pH of glutaraldehyde solution, time of membrane-glutaral-dehyde reaction) and to reaction of glutaraldehyde-pretreated membranes with urease (concentration and pH of urease solution). The obtained membrane has high enzymatic activity, and can be applied for enzymatic removal of urea e.g. in the treatment of chronic or acute uraemia.