Patent ID: 6328866
Filing Date: 2001-12-11
Classification: G01N

Abstract:
An ion sensor comprising:an ion sensor plate main body provided with at least one group of an electrode pair, each group having a test liquid-measuring electrode and a reference electrode, each of the test liquid electrode and the reference electrode being provided with a silver halide layer formed on a silver layer and with an ion sensitive membrane which is sensitive to a specific ion and formed on said silver halide layer; anda measuring circuit connected with said ion sensor plate main body for measuring a concentration of said specific ion in said test liquid,wherein said ion sensitive membrane contains an electric potential-stabilizing agent which is capable of stabilizing an electric potential at an interface between said silver halide layer and said ion sensitive membrane, andthe ion sensor being further provided with a test liquid-feeding passageway for supplying said test liquid to said test liquid-measuring electrode and with a reference liquid-feeding passageway for supplying said reference liquid to said reference electrode, wherein at least said test liquid-feeding passageway among these passageways is provided with a coated film of surfactant which is capable of adding said surfactant to said test liquid as said test liquid passes through said test liquid-feeding passageway.