CONCENTRATION OF ENZYMES ADSORBED ONTO LANGMUIR FILMS AND CHARACTERISTICS OF A UREA SENSOR

The concentration of enzymes, urease and glucose oxidase, adsorbed onto stearylamine and cetylamine monolayers at the air-water interface was measured. The density of pinholes in cadmium stearate Langmuir-Blodgett (LB) films was also estimated by the copper decoration method and a mechanism of generation of the pinholes was suggested. We have made a urea sensor using an ion-sensitive field effect transistor as a transducer on which urease was immobilized by the LB technique. We have shown that the characteristics of the urea sensor can be considerably improved by using the LB technique.