| Popis: |
Two types of amperometric lactose enzyme sensors based on the enzyme systems galactose oxidase (single-enzyme electrode), or β-galactosidase and glucose oxidase (two-enzyme electrode) with a hydrogen peroxide base electrode were constructed. The enzymes were chemically immobilized onto a dialysis membrane using the BSA/glutaraldehyde method. The properties of two types of lactose sensors were compared, and factors which influence electrode response, such as buffer, pH, and immobilization of enzyme, were studied. The calibration curve for lactose is linear in the range between 1 × 10-5 and 1 × 10-1 m, at room temperature, in a phosphate buffer (0.2 m, pH 7.38). The response times were |
