Glucose oxidase membrane preparation

Two similar approaches were adopted by Ishihara et al. [364-368]. Membranes based on hydroxyethyl acrylate, dimethylaminoethyl methacrylate and trimethyl silyl styrene were solvent cast, and capsules containing insulin and glucose oxidase were prepared by interfacial precipitations. The authors reported dramatic changes in permeability in response to pH changes between 6.1 and 6.2. Moreover, addition of glucose induced an increase in the permeation rate of insulin, and upon removal of the glucose the permeability rates returned to their original levels. However, the conclusions were criticized [361] due to... 

Enzyme containing Nation membranes prepared according to the proposed protocol have shown high specific activity and stability of immobilized glucose oxidase. As expected, the simplicity of preparation provided high reproducibility. When the same casting solution is used, the maximum deviation in membrane activity is <2%. This, however, is also the precision limit for kinetic investigations. 

Glucose oxidase, glycoproteins from plasma membranes of rat liver Analytical and semi preparative separations Lectin Affinity (Concanavalin A) disks [76]... 

Membranes that swell in the presence of glucose have been prepared by immobilizing glucose oxidase in an amine-containing... 

The micropool injection method was developed by Miyahara et al. (20), and independendy by Kimura and his collaborators (15,16, 43). It was successfully used for a monolithic enzymatically coupled FET, sensitive to urea and glucose, and for the urea-, glucose-, and potassium-sensitive trifunctional FET biosensor (see Section 2.3). The thickness of an enzyme membrane is about 10 pm, and the thickness of an enzyme-immobilized membrane prepared by the ink jet-micropool injection method is 0.1 -1 pm. The lift-off method was developed by Kimura and Kuriyama s group and used for the deposition of a urease- and a glucose oxidase-immobilized membrane (16, 17) (see Fig. 8(3)). The enzyme membrane thickness is similar to the thickness of the film resist layer, about 1 pm thick. 

The photopolymer solution used for the immobilization of lipase on a FET contained 10% PVP and 0.3% BASC (7, 13). A lipase-immobilizing soludon was prepared by dissolving 150 mg of lipase and 100 mg of bovine serum albumin in 1 mL of the photopolymer soludon. A photolithographic lipase membrane was formed on one of two FET elements, similar to the glucose oxidase and urease membranes, except that the development was done in water. After the development, the lipase-immobilized membrane was immersed in a 3% glutaraldehyde soludon for the addidonal chemical cross-linking of the protein molecules. 

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