Patent ID: 7491310

Claim:
A concentration measuring method for measuring concentration of a particular component in a sample liquid using a test tool; the test tool comprising: a capillary for moving the sample liquid, an operative electrode, a first counterpart electrode arranged upstream from the operative electrode in a moving direction of the sample liquid, a second counterpart electrode arranged downstream from the operative electrode in the moving direction of the sample liquid; wherein the method comprises: a first detection step for detecting whether or not liquid conduction is established between the operative electrode and the first counterpart electrode by detecting a response current between these two electrodes under voltage application; a second detection step performed after conduction is detected in the first detection step for detecting whether or nor liquid conduction is established between the operative electrode and the second counterpart electrode by detecting the response current between these two electrodes for detecting a response current under voltage application; a measurement step performed after conduction is detected in the second detection step for measuring a response current between the operative electrode and the first counterpart electrode or between the operative electrode and the second counterpart electrode under voltage application; and a concentration computation step for computing the concentration of the particular component based on the response current measured in the measurement step, the computation of the concentration being also based on a lapse time between conduction detection in the first detection step and conduction detection in the second detection step.