Patent ID: 6525549
Filing Date: 2003-02-25
Classification: G01N

Abstract:
A method for the determination of the concentration of a substance in a liquid, in which the liquid to be investigated is applied to a chemical containing areal test field (18) of a test strip (14) processed by electrical current measurement and wherein an oxidation current strength effected in the test field (18) by reaction of the applied liquid with the test field chemical has a timewise course, said method comprising, providing a test strip (14) such as aforesaid, applying a quantity of a liquid to be investigated to the test field (18) of the test strip to produce a timewise course of oxidation current strength in the test field, capturing the timewise course of the oxidation current strength within a time interval calculated from the beginning of the fluid application, investigating the captured timewise course of the oxidation current strength to define a first extreme value (34) of the current strength, comparing said first extreme value (34) of the current strength with at least one threshold value, and providing an indication depending on the result of the comparison.