Patent ID: 7250096

Claim:
A method of performing electrophoresis utilizing a capillary, the method comprising: filling the capillary with a separating medium; applying a voltage to a current-carrying path including the separating medium prior to performing electrophoresis, the applied voltage being smaller than a voltage that is applied during electrophoresis; detecting a first value of the electric current flowing in the current-carrying path; determining a state of the current-carrying path based on the first value of the electric current that is detected; performing electrophoresis while detecting a second value of the electric current flowing in the separating medium after determining that a state of the current-carrying path is suitable for electrophoresis; and terminating performing electrophoresis based on the detected second value of the electric current, wherein electrophoresis is terminated when a rate of change of the detected second value of the electric current has exceeded a predetermined value.