Pipetting device for pulsed pipetting with a pipetting piston movement regulated on the basis of a detection of the working gas pressure

摘要

A pipetting device (10) for the pulse-like pipetting of dosing liquids in small dosing volumes of less than 2 μl, the pipetting device (10) comprising: - a pipetting channel (11) at least partially filled with working gas (34), - a pipetting tip (26) which is accessible through a pipetting opening (30), so that by changing the pressure of the working gas in the receiving space through the pipetting opening (30) the amount of dosing liquid accommodated in the receiving space can be changed, 14) for changing the pressure of the working gas (34), - a movement drive (20) to drive the pipetting piston (14) for movement along the pipetting channel (11), - a control device (24) for controlling the movement drive (20), and - A pressure sensor (38) for detecting the pressure of the working gas, the control device (24) being designed for this det is to control the movement drive (20) to generate a pressure pulse in the pipetting channel (11) with a pulse duration of not more than 40 ms on the basis of the pressure signal output by the pressure sensor (38) that the pressure of the working gas (34) during the Pulse follows a predetermined working gas target pressure pulse curve.