Immobilized-enzyme rate-determination method for glucose analysis.

We present a rate-determination method for analyzing glucose. A glucose enzyme electrode serves as the sensor and is made by placing a gel-immobilized layer of glucose oxidase over the tip of a Clark-type O2 electrode. The electrode membrane is made of Teflon and is derivatized by etching with a suspension of colloidal sodium metal in organic solvent. The enzyme is coupled to the membrane surface by use of paraformaldehyde. The immobilized-enzyme method is compared with a similar solution-enzyme method and with the National Glucose Reference method. The immobilized enzyme method compares favorably with the solution-enzyme method and offers the advantages of simplicity, economy of enzyme, and linearity over a greater range of concentration.