Patent ID: 7708874

Claim:
An electrophoresis apparatus for adding a sample into channels, making the sample migrate electrophoretically by voltage application, and optically detecting the sample, said apparatus comprising: a plate on which the channels are formed; a tray on which said plate is set; a voltage application unit having voltage application electrodes for applying voltage to a sample in the channels on said plate; a tray driving unit for rotary driving said tray on which said plate is set; an optical detection part having a light irradiation unit for irradiating the sample in the channels with light, and an optical detection unit for detecting light which is emitted from the sample when the sample is irradiated with the light from the light irradiation unit; a plate holding member for pressing only the channel formation areas of said plate against a plate setting surface of said tray, thereby fixing and holding said plate on the plate setting surface of said tray; and a voltage application contact/separation unit for making the voltage application electrodes of said voltage application unit contact with or apart from predetermined positions of said plate; wherein the voltage application electrodes of said voltage application unit are brought into contact with the predetermined positions of said plate by said voltage application contact/separation unit to make the sample migrate electrophoretically by voltage application, and thereafter, the voltage application electrodes of said voltage application unit are separated from the predetermined positions of said plate by said voltage application contact/separation unit, and the light emitted from the sample in the channels on said plate is detected by the optical detection part, and wherein said plate holding member has a convex configuration in which its center portion projects relative to its circumference portion, and presses said plate against the plate setting surface of said tray by the circumference portion.