Detection element-spedfic

Figure 8.95 Separation of iodate and iodide with element-spedfic detection. Separator column ExcelPak ICS-A23 eluent 30 mmol/L ammonium carbonate, pH 9.4 flow rate 15 mlVmin detection ICP-MS peaks 50 nmol/L iodate (1) and iodide (2) (courtesy of Agilent Technologies).

In recent years, the coupling of ion chromatography with element-specific detection methods has increasingly gained importance. Element-spedfic detection is carried out with atomic spectrometric techniques induding atomic absorption spectrometry (AAS), atomic emission spectrometry (ICP-OES) as well as the coupling between ICP and mass spectrometry (ICP-MS). 

Gas and liquid chromatography Coupled with ICP-OES these are useful approaches for speciation work, as shown by the early work of Cox et al. [482] for Cr /Cr speciation, where AI2O3 filled columns and elution with adds and NaOH were used. Anion exchangers could also be used. New impetus has arisen from the interfacing of thermospray and high-pressure nebulization to ICP-OES. ICP-OES remains of interest for the element-spedfic detection in the speciation of silicon compounds and is a good alternative to ICP-MS, where considerable spectral interferences hamper the power of detedion that can be obtained. 

L. Colon and G. Barry, Alternating current plasma emission detection in HPLC. In Element Spedfic Chromatographic Detection by Atomic Emission Spectroscopy, Ed. by PC. Uden, ACS Symposium Series, American Chemical Sodety, Washington, DC, 1990, in press. 

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