US Patent 7351323 Quantitative analyzing method and quantitative analyzer using sensor

A quantitative analyzing method is provided for electrochemically measuring the concentration of a substance in a sample liquid using a sensor including a reagent layer (30) which contains a reagent for reacting with the substance and to which (30) the sample liquid is introduced, and a first electrode (22) and a second electrode (23) for applying a voltage to the reagent layer (30). The method includes a current measuring step for applying a voltage across the first electrode (22) and the second electrode (23) for measuring current flowing between the first and the second electrodes (22,23), a parameter calculating step for calculating a parameter based on the measured current, and a determining step for determining a state of the sample liquid introduced to the reagent layer (30) based on the parameter and at least one predetermined constant.