AUTOMATIC PIPET DEVICE AND TITRATION METHOD USING SAID DEVICE

摘要

A method for pipetting with a pipette (10) is disclosed. The pipette has a motor driven linear actuator and, connected to the linear actuator, a pipetting displacement assembly (14) including a displacing piston (50) movable within one end (103) of a displacement cylinder (24). The cylinder (24) has a displacement chamber (26) and another end with an aperture communicable with liquid to be pipetted. The method comprises the steps of: retracting the displacing piston (50) a predetermined first distance in the displacement cylinder (24) to compensate for air pressure and surface tension effects to cause liquid to begin to move into the displacement chamber (26); and retracting the piston a second distance to draw in the volume to be pipetted; whereby the total volume of pipetted liquid taken in is less than the total displacement of the piston.