Method for operating a dosing device

Abstract

The present application relates to a method for operating a dosing device with a control unit and a dosing unit. The dosing unit has a cannula with a first volume and a tip, and also a sampling container fluidically connected to the cannula. In a first step, the dosing unit is moved linearly at a predetermined speed in a first direction along an axis, such that the cannula is moved into a vessel containing at least one liquid. At the same time, fluid is aspirated constantly through the cannula with a predetermined volumetric flow by a pump device. At least one optical parameter of the aspirated fluid is measured by at least one optical sensor, which is arranged between the cannula and the sampling container. When a change of the at least one optical parameter is detected, a first position of the dosing unit on the axis is stored by the control unit and the movement of the dosing unit is interrupted. The control unit then calculates a second position of the dosing unit on the axis, at which second position the tip of the cannula has penetrated a first phase boundary, in particular upon immersion into the liquid. The calculation is performed on the basis of the first position, the predetermined speed, the first volume and the predetermined volumetric flow.

Dependencies are inferred from the claim text.