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