Patent ID: 8349161

Claim:
An electrophoresis device comprising: at least one capillary to be filled with an electrophoresis medium; a voltage source that applies a voltage to ends of the capillary; an optical detection mechanism that optically detects a sample separated by electrophoresis in the capillary; and a pump which includes a tubular container arranged obliquely to a vertical direction, a plunger operated along an inner wall of the container, an outlet through which the electrophoresis medium is filled into the capillary, and an inlet through which the electrophoresis medium is caused to flow into the container and which has a clearance formed between a side wall of the container and a side wall of the plunger in such a manner that a portion of the clearance in a region on an upper side in the vertical direction has a cross-sectional area larger than a cross-sectional area of the other portion of the clearance.