The invention relates to device for enriching and depleting materials in a liquid. Said device comprises a pump for advancing the liquid and said pump comprises a displaceable transport element (1) which transports the liquid. Said device is advantageous in that it comprises an insertable and retractable transport and drive unit and it is particularly advantageous in that the flow guiding element effectively enriches and depletes material in the liquid. The invention also relates to a fluidic rotor bearing for mounting the transport element. It is also possible to connect a two lumen cannula by means of a concentric connection module. Due to said device, a compact oxygen generator system, which is based on an integrated and re-usable blood-pump, is produced which can be used in blood.
