On-line removal of anions for plant analysis by inductively coupled plasma mass spectrometry

The multi-element determination of B, Al, Cu, Zn, Mn, Fe, Cr, Cd, Pb and S in plant digests by ICP-MS with on-line removal of anions is presented, A column with the anionic resin AG1-X8 was placed in a flow system to remove mainly sulfate and chloride while the solution was flowing to the ICP-MS system for the determination of the other elements, Subsequently, the sulfur retained by the column was eluted and determined at m/z 48, The effect of perchlorate on sulfate retention was studied. Interferences on isotopes Cu-65, Zn-64, Zn-67 and Cr-53 were minimized using this approach. The analytical range was from 0.2 to 1.0% S for the vegetable samples analyzed, The detection limit was 0.02% S (dry basis). Results from reference materials (NIST SRM 1573a Tomato Leaves and ORSTOM palmier and pommier golden) were in agreement with certified values at the 95% confidence level.