Method for dosing liquid volumes, wherein a sample pickup portion with a
pickup volume, the boundary of which is perforated with a liquid passage
guiding to the outside and a gas passage, is dipped into a liquid with
the liquid passage, a negative pressure is suddenly applied to the gas
passage, which is generated by a gas displacement system, a drive of the
gas displacement system is readjusted such that a constant negative
working pressure exists in the sample pickup portion, the taken sample
volume is detected with the aid of the readjusted driving path of the
drive, the detected taken volume is compared with a predetermined value
of the volume that is to be taken, when the predetermined value is
reached by the taken volume, the negative pressure applied on the sample
pickup portion is suddenly abated, the sample pickup portion with the
liquid passage is pulled out of the liquid the sample pickup portion with
the liquid passage is directed towards a releasing location, one ore more
flow parameters is/are determined from the values of the taken volume,
the negative working pressure and the time period required to take up the
volume, an overpressure is applied to the gas passage of the sample
pickup portion, the moment at which a volume that is to be released is
released is determined with the aid of the flow parameter(s) and the
overpressure, and when the moment is reached, the overpressure applied to
the sample pickup portion is suddenly abated.