As(III) or As(V) - Speciation analysis of arsenic by IC-ICP-MS
In a study recently published in Analytica Chimica Acta (2014), Wolle et al. present an extraction method for the comprehensive speciation analysis of arsenic in prenatal and children's dietary supplements prepared from plant material such as fruits, vegetables, grains, and herbs. The extracted arsenic was speciated IC-ICP-MS using a Metrohm 850 Professional IC coupled to an Agilent 7700x ICP-MS.
As the authors point out, numerous methods have been described for extracting arsenic from all kinds of samples ranging from environmental to nutritional, botanical, biological, and others. However, as the authors emphasize, the method described in their paper is the first dedicated specifically to the extraction of arsenic species from dietary supplements for small children and pregnant women.
In a nutshell, the result of the study is that a solution of H3PO4 can be used to extract arsenic from the samples investigated without significantly affecting the stability of the arsenic species. The results of the analysis by IC-ICP-MS were validated using mass balance by comparing the sum of the extracted and and non-extracted arsenic with the total concentration of the element in the corresponding samples.
Source: Metrohm AG