Patent ID: 8702923

Claim:
An apparatus for measuring a sample reaction result on a biosensor having a working electrode, a counter electrode, and a checking electrode, the apparatus comprising: switches configured to selectively connect each of the counter electrode and the checking electrode to a ground terminal; an amplifier configured to be connected at one terminal to a voltage source and at another terminal to the working electrode of the biosensor, so as to detect an amount of current flowing through the working electrode; and a microprocessor programmed to: control the switches so that a voltage can be applied between the working electrode and the checking electrode upon coupling of a sensor strip, detect an amount of first current flowing through the working electrode and checking electrode, control the switches so that a voltage can be applied between the working electrode and the counter electrode, detect an amount of second current flowing through the working electrode and counter electrode, determine whether or not a sample is properly injected by comparing the detected amounts of the first and second currents and a time interval between times when the first and second currents are detected with predetermined threshold values, if it is determined that the sample is properly injected, apply a voltage between the working electrode and the counter electrode and detect an amount of third current flowing through the working electrode, and acquire and display a concentration value as a sample reaction result corresponding to the detected amount of third current on a display unit.