Separation of inorganic anions on a high capacity porous polymeric monolithic column and application to direct determination of anions in seawater

✍ Scribed by Christopher J. Evenhuis; Wolfgang Buchberger; Emily F. Hilder; Kelly J. Flook; Christopher A. Pohl; Pavel N. Nesterenko; Paul R. Haddad

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 667 KB
• Volume: 31
• Category: Article
• ISSN: 1615-9306
• DOI: 10.1002/jssc.200800205

✦ Synopsis

Abstract

A commercially available 4.6 mm id×50 mm polymethacrylate‐based monolithic strong anion exchange column (ProSwift^TM^ SAX‐1S) designed for the separation of proteins has been successfully used to separate small inorganic anions in the presence of a seawater sample matrix. Using a hydroxide eluent with suppressed conductivity detection the ion exchange capacity of this column declined over time; however, using KCl as the eluent, the column performance was stable with a capacity of 530 μequiv. for nitrate. The optimum conditions for the separation of iodate, bromate, nitrite, bromide and nitrate were assessed by constructing van Deemter plots using 1.00 and 0.100 M KCl. Efficiencies of up to 26 700 plates/m were recorded using 1.00 M KCl, at a flow rate of 0.20 mL/min but iodate was not baseline resolved from the void peak. By reducing the concentration of the eluent to 0.100 M, efficiencies of up to 39 900 plates/m could be obtained at 0.35 mL/min. By employing a linear gradient ranging from 0.05 to 1.00 M KCl the ions dissolved in distilled water or a salt water matrix could be baseline separated in less than 3 min at a flow rate of 2.50 mL/min.