Organic acids and anions play an essential role in both environmental and biological processes. Determination of these molecules is important for both quality control and research laboratories. This application note shows the efficiency of CElixirOA™ to separate Nitrites from Nitrates and Oxalic Acid using pH 2.5.

Method:
Using a Beckman P/ACE MDQ™ HPCE System and 75µm ID bare fused silica capillary, the analysis and separation of Nitrate from Nitrite from Oxalic Acid is easily achieved. The concentration of the analytes was below 10mg/ml and was hydrodynamically injected for 5 seconds. The capillary was conditioned according the CElixirOA™ manual. The separation was completed in less than 5 minutes.

Discussion and Rationale:
Many small anions are UV absorbing and the proper choice of the absorbing background electrolyte is important for good peak shape and sensitivity. CElixirOA pH 2.5 Kit contains phosphoric acid as the background electrolyte. Using a polycationic, dynamic coating technology of CElixir the separation shown is possible and easy with no hassles of mixing solutions or preparing any run buffers on your own. There is no problem determining trace levels of nitrite in the presence of large amounts of nitrate.

Comments:
CElixirOA™ provides simple, reliable and rapid separations covering a wide range of applications. With good linearity and reproducibility below 0.5% RSD for migration times (click here to view chart) CElixirOA™ is a valuable alternative to traditional techniques such as Ion Chromatography.