Optimisation of ICPMS collision/reaction cell conditions for the simultaneous removal of argon based interferences of arsenic and selenium in water samples.

The optimisation of ICPMS collision/reaction cell conditions for the simultaneous analysis of arsenic and selenium is described. A mixture of 3.8mL min(-1) of H(2) and 0.5mL min(-1) of He was found to be suitable for the removal of both ArAr(+) and ArCl(+) interferences. Detection limits down to 30ng (element) L(-1) in total analysis, and between 81 and 230ng (element) L(-1) in speciation analysis were achieved in chloride matrix (1gL(-1) NaCl). After validation, the method was applied to commercially available mineral waters.