title: Enzyme sensors based on an ion-sensitive field effect transistor coated with Langmuir-Blodgett membranes. Use of polyethyleneimine as a spacer for immobilizing alpha-chymotrypsin.
abstract: A highly branched polyethyleneimine (PEI) was used as a spacer for immobilizing alpha-chymotrypsin on the surface of Langmuir-Blodgett (LB) membranes which were deposited on the gate of an ion-sensitive field effect transistor (ISFET). alpha-Chymotrypsin could be covalently immobilized through the glutaraldehyde-activated PEI on the LB membrane-coated ISFET. The alpha-chymotrypsin-modified ISFET showed a potentiometric response to the substrate at concentrations of more than 0.1 mM. Some performance characteristics of the sensor, such as pH response, response time, and long-term stability were examined.
authors.forename: J
authors.initials: J
authors.lastname: Anzai
authors.forename: S
authors.initials: S
authors.lastname: Lee
authors.forename: T
authors.initials: T
authors.lastname: Osa
mesh_terms: D002918:Chymotrypsin; D004566:Electrodes; D004798:Enzymes / Q000032:analysis*; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D011094:Polyethyleneimine; D011199:Potentiometry; D014173:Transistors, Electronic
chemical_list: D004798:Enzymes; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D011094:Polyethyleneimine; D002918:Chymotrypsin