Abstract:
Objective To establish an analytical method for determining chromium speciation in drinking water by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS).
Methods After the sample was complexed with EDTA-2Na, a Dionex IonPac AS7 chromatographic column was used with a mobile phase of 0.075 mol/L nitric acid and 0.6 mmol/L EDTA-2Na for isocratic elution, and liquid chromatographic separation was performed. ICP-MS was used for qualitative and quantitative analyses, and chromium speciation was determined within 2 minutes.
Results This method had a limit of detection of 0.2 μg/L for Cr(Ⅲ) and 0.3 μg/L for Cr(Ⅵ), and a good linear relationship was observed within the range of 1.00-80.0 μg/L, with a correlation coefficient higher than 0.999. The spike recovery was 83.7%-115.3%, with a relative standard deviation of < 5%.
Conclusion The method established in this study is rapid, accurate, reliable, and sensitive and can be used for the quantitative determination of chromium speciation in drinking water.