Patent ID: 8636963

Claim:
A non-electrolytic apparatus for treating an aqueous sample stream including analyte ions and matrix ions of opposite charge, said apparatus comprising a first ion exchange membrane capable of passing only ions of opposite charge to said analyte ions, a sample stream flow channel, a first aqueous stream ion receiving flow channel adjacent one side of said sample stream flow channel and separated therefrom by said first ion exchange membrane, stationary flow-through first packing of ion exchange material disposed in the sample stream flow channel of the same charge as said first membrane and having a first ion exchange capacity for said matrix ions, said first ion receiving channel having second flow-through ion exchange packing of opposite charge to said first ion exchange packing disposed in said sample stream flow channel, the ion exchange packing in said first ion receiving flow channel consisting essentially of said second flow-through packing, said apparatus not including electrodes disposed to apply an electric field between said sample stream flow channel and said first ion receiving flow channel.