By expanding the conventional SI system with an external pump and a multiposition valve, the target analytes can be retained (top) on several different types of sorbents and eluted separately (below) into a detector.
An example of such application is the recycling Immunity Chromatography (Phillips, Krum 1998) for assay of multiple analytes. The method is based on passing labeled biomolecules from crude biological samples through a series of columns containing different specific bioligands. Acid elution will release the analytes sequentially as the columns are sequentially addressed by the multi- position valves in sequence.
Separation on Sequential Columns
2.3.20.
Sorbent extraction in combination with ion exchange on a sequential column system is a novel, powerful tool for multiple element speciation and analysis of fresh and sea water.
Phillips T.M, Krum J.M.; J. Chromatography B 715 (1) 55, 1998
