Abstract: A sensor for measuring the concentration of an analyte in a solution is disclosed. The sensor may be adapted for use as either an amperometric or a potentiometric sensor. It includes a membrane having a biologically active protein immobilized within. The membrane is attached and reliably sealed to a housing by means of ultrasonic welding, either directly or indirectly. Further, the membrane may be compressed to a fraction of its original dimensions. Metallic parts of the device may, optionally, be physically isolated from the sample solution to reduce corrosion. These features operate synergistically so that the claimed device exhibits relatively fast response and recovery times, is reliably leak-proof, and may be constructed in relatively small sizes.

Abstract: An ion-selective electrode having an electrically insulating substrate with a substantially planar first surface, and having a non-metallic conductor for sensing a potential affixed to the first surface beneath an ion-sensitive membrane. An electrically insulating layer covers at least a portion of the non-metallic conductor and means for making electrical contact with the non-metallic conductor.

Abstract: A membrane anchor for an ion-selective electrode may be formed by intersolubilizing an ion-selective membrane lying above a sensing pad with a region of thermoplastic material laterally disposed around the membrane. A first layer of electrically insulating thermoset material lies beneath the thermoplastic material and in intimate contact with an electrically insulating substrate. A second layer of exposed thermoset material lies above the thermoplastic material and contacts the first layer of thermoset material around the entire lateral perimeter of the thermoset material.The membrane anchor may be usefully employed with an ion-selective electrode having an electrically insulating substrate with a substantially planar surface and having non-metallic means for sensing a potential affixed to the surface beneath an ion-sensitive membrane.