Automatic electrophoresis method and apparatus

An electrophoresis apparatus for automatically performing medical assays includes an electrophoresis platform which cooperates with a gantry assembly. The electrophoresis platform and the gantry assembly are movable along paths that are perpendicular to each other. An applicator assembly includes pipettes which transfer fluid samples from a specimen tray to an electrophoresis plate mounted on the electrophoresis platform. The electrophoresis platform then moves to a position into the gantry assembly, where electrophoresis is conducted to separate the samples into different fractions. The electrophoresis platform then moves beneath a reagent pouring station where a reagent is applied to make the separated fractions fluoresce under ultraviolet light. The electrophoresis platform is then moved beneath the gantry assembly again, and an air knife in the gantry assembly spreads the reagent. After incubation and drying of the electrophoresis plate, the electrophoresis platform and gantry assembly are moved relative to one another while the electrophoresis plate is read with the aid of ultraviolet lamps and a photomultiplier tube mounted in the gantry assembly. The gain of the photomultiplier tube is automatically adjusted and the data gathered is automatically edited to remove background noise. The edited results can be printed or displayed on a video monitor. Techniques for calibrating the electrophoresis apparatus are also disclosed.