Patent ID: 7704749

Claim:
Chromatography apparatus comprising: (a) at least one contaminant ion-purifying housing defining at least one purifying flow channel having an inlet and outlet and including ion exchange medium having exchangeable ions of one charge, positive or negative, disposed in said one purifying flow channel, (b) a source of an aqueous liquid stream including at least one contaminant ion of the same charge as the exchangeable ions of said purifying housing ion exchange medium and in liquid communication with said purifying flow channel inlet, (c) spaced first and second electrodes of opposite charge disposed to apply an electric field through said one purifying flow channel, (d) chromatographic separation medium in a chromatographic separator having an inlet and an outlet, said chromatographic separation medium having exchangeable ions of the same charge as said contaminant ion, positive or negative, said separation medium inlet being in liquid communication with said one purifying flow channel outlet, and (e) a sample injector disposed between said housing outlet and said chromatographic separation medium inlet.