Immobilization of cholesterol oxidase on Formvar using organic solvents

The present study describes a new immobilization support for the preparation of enzyme membrane in the presence of organic solvents. The support was composed of Formvar solubilization in organic solvents with enzyme. More than 90% of the enzyme was immobilized on the membrane. The membrane was prepared by mixing 4% Formvar in organic solvents and 1% cholesterol oxidase was immobilized by entrapment technique. Practically no leaching of the entrapped enzyme was observed. The resultant immobilized enzyme membrane was stored at 4 degrees C for 10 days without losing its activity. The pH and temperature stabilities were greater than those of the native enzyme. The immobilized enzyme membrane has a long life due to its hydrophobic nature, as compared with other membranes.