Electrochemical sensors

Claim 1

AN ELECTORDE ASSEMBLY COMPRISING IN COMBINATION: A FIRST BODY OF CHEMICALLY INERT, ELECTRICALLY NONCONDUCTIVE MATERIAL ADAPTED TO BE IMMERSED IN A TEST SOLUTION, SAID FIRST BODY DEFINING A CHAMBER WITH AN OPENING IN A WALL OF SAID FIRST BODY LEADING INTO SAID CHAMBER; A SEALING SURFACE ON SAID FIRST BODY ENCOMPASSING SAID OPENING; AN ELECTROLYTE SOLUTION IN SAID CHAMBER; A SOLID BODY OF ELECTROLYTIC BRIDGE MATERIAL HAVING FIRST AND SECOND OPPOSITELY DISPOSED SEALING SURFACES AND POSITIONED SO AS TO HAVE SAID FIRST SEALING SURFACE CONTACTING SAID SEALING SURFACE ON SAID FIRST BODY; A SECOND BODY OF CHEMICALLY INERT, ELECTRICALLY NONCONDUCTIVE MATERIAL CONTACTING SAID SECOND SEALING SURFACE; FASTENING MEANS ACTING BETWEEN SAID FIRST AND SECOND BODIES TO MAINTAIN INTIMATE CONTACT BETWEEN SAID SEALING SURFACES AND HOLD SAID BODY OF BRIDGE MATERIAL IN SAID POSITION WITH ONLY A PERIPHERAL PORTION EXPOSED TO THE TEST SOLUTION AND AN INTERIOR PORTION THEREOF EXPOSED TO SAID ELECTROLYTE, AND AN ELECTRODE DISPOSED WITHIN SAID FIRST BODY AND CONTACTING SAID ELECTROLYTE.