Patent Number: 6,685,807

Title: Measuring probe for potentiometric measurements, method of monitoring the state of aging of the measuring probe, and use of the measuring probe

Abstract: A measuring probe for potentiometric measurements has a housing (2) of an electrically insulating material surrounding an enclosed space (4). Inside the space (4) are a primary reference element (6), a secondary reference element (8), an electrolyte (10), and an ion-permeable, micro-porous, high-viscosity polymer substance which, in combination with the electrolyte (10), forms a filler mass (16). The housing (2) has at least one opening (12) to the outside, through which the electrolyte (10) can be brought into contact with a sample solution on which a measurement is to be performed. The secondary reference element (8) is arranged so that the boundary (52) of an electrolyte-deficient region (54) advancing over time from the opening (12) towards the primary reference element (6) arrives at the secondary reference element (8) before reaching the primary reference element (6).

Inventors: Meier; Peter C. (Wohlen, CH)

Assignee: Mettler-Toledo GmbH

International Classification: G01N 27/403 (20060101); G01N 27/401 (20060101); G01N 27/28 (20060101); G01N 027/26 ()

Expiration Date: 02/03/2021