Condensed phosphates exchange chromatography

Shaver and Stites have found that combined sulfate can be separated from ionic sulfate by ion-exchange chromatography. The anion-exchange method employed by Peters and Pieman (50) for the separation of polyphosphates is adapted for this purpose. Ionic sulfate present in the form of sodium sulfate in a sample is readily eluted in a manner similar to orthophosphate. Combined sulfate present as condensed sulfate-phosphate, however, is strongly held on the resin and can only be eluted after hydrolyzing the sulfate-phosphate on the resin column with warm hydrochloric acid. 

The ionizable phosphate group present in organic phosphorus species provides the basis for separation by anion exchange chromatography. This approach has been applied to the separation of phosphate, inositol phosphates, organic condensed phosphates, nucleic acids, nucleoside phosphonates, phospholipids and other organic phosphorus species. 

Figure 3 (A) Ion-exchange chromatography-FIA system for separation of polyphosphates. (B) Optimized separation of orthophosphate (50 pgPI diphosphate (SOpgPr ), and triphosphate (SOngPI ) with an injection volume of 500 iit. (Halliwell DJ, McKelvie ID, Hart BT, and Dunhill RH (1996) Separation and detection of condensed phosphates in waste waters by ion chromatography coupled with flow injection. Analyst (Cambridge, UK) 121 1089-1093 reproduced by permission of The Royal Society of Chemistry.)...

Anion exchange chromatography and ion exchange chromatography have been used extensively for the separation and quantitation of condensed phosphates. Because phosphate is a poor UV chro-mophore, direct UV detection cannot be used, and fraction collection for subsequent acid hydrolysis and detection as molybdate reactive phosphorus (MRP)... 

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