ONLINE 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 a nd S in plant digests by ICP-MS with on-line removal of anions is pres ented, A column with the anionic resin AG1-X8 was placed in a flow sys tem to remove mainly sulfate and chloride while the solution was flowi ng to the ICP-MS system for the determination of the other elements, S ubsequently, the sulfur retained by the column was eluted and determin ed at m/z 48, The effect of perchlorate on sulfate retention was studi ed. Interferences on isotopes Cu-65, Zn-64, Zn-67 and Cr-53 were minim ized 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 (d ry basis). Results from reference materials (NIST SRM 1573a Tomato Lea ves and ORSTOM palmier and pommier golden) were in agreement with cert ified values at the 95% confidence level.