[Study of kinetic parameters of glucose oxidase and alpha-chymotrypsin, immobilized in polymeric matrices, using a light-addressable sensor].
Light-addressable potentiometric sensors were prepared by immobilizing glucose oxidase or alpha-chymotrypsin on the surface of a pH-sensitive electrode. Two methods of immobilization were used: incorporation into a hydrophilic matrix of bovine serum albumin and incorporation into a hydrophobic matrix of modified polyethylenimine. The glucose oxidase and alpha-chymotrypsin preparations immobilized in the polyethylenimine matrix were characterized by the Michaelis constant values of 6.0 and 3.1. mM, respectively, and by pH optimums at 6.0-7.2 and 7.0-8.0, respectively. These values are consistent with results obtained by other methods. Therefore, light-addressable potentiometric sensors can be used in combination with both hydrophilic and hydrophobic matrices. The ability to combine light-addressable potentiometric sensors with hydrophobic matrices provides an opportunity for the development of potentiometric biosensors for detecting substances poorly soluble in water.