A separation method to overcome the interference of calcium on the uranium determination by ICP-ES

The accurate determination of uranium by Inductively Coupled Plasma Emission Spectrometry (ICP-ES) in calcium phosphate matrix suffers from a severe ionization interference due to the high calcium content of the samples. This leads to a signal depression up to 30%. For reliable determinations an extraction method based on anion exchange resin column chromatography is described which separates uranium for the needs in ICP-ES measurements. The results are comparable with results obtained by other determination methods. In addition, reference materials were measured to verify this extraction procedure.