Chelating resins Chemical analysis

Preconcentration of selected metal ions is probably the main use of chelating resins in chemical analysis. Trace amounts of complexed metal ions may be concentrated from a large sample onto a very short column. Subsequent elution by acid breaks up the metal chelates and gives a much more concentrated solution of the metal ions for further analysis. However, a column packed with a chelating resin may also be used to separate sample metal ions based on differences in the strength of their chelates. 

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