Mixed-mode ion-exchange polymeric sorbents: dual-phase materials that improve selectivity and capacity

A review. In this article, we describe mixed-mode polymeric sorbents, which, in a single material, enhance the selectivity and the capacity of the extn. process. We have structured the article around the four types of mixed-mode sorbents (i.e. strong/weak and cation/anion-exchange materials). We cover different aspects of these materials, starting with a proper understanding of their morphol. and chem. properties, so that the appropriate sorbent can be selected for each particular case. We deal with another important issue - the solid-phase extn. protocol recommended for each type of sorbent to enhance its specific properties. We also provide a list of all the mixed-mode polymeric sorbents both com. available and prepd. inhouse. Finally, we discuss the leading applications of the types of analytes and the matrixes extd. using these materials and illustrate them with selected examples.