Pneumatic nebulizer as a dilution chamber in a flow-injection system for multielement analysis by ICP-MS.

Abstract

An automatic dispenser based on a flow-injection system used to introduce sample and analytical solution into an inductively coupled plasma mass spectrometer through a spray chamber is proposed. Analytical curves were constructed after the injection of 20 to 750 mu L aliquots of a multielement standard solution (20.0 mu g L-1 in Li, Be, Al, V, Cr, Mn, Ni; Co, Cu, Zn, As, Se, Sr, Ag, Cd, Ba, Tl, Ph) and the acquisition of the integrated transient signals. The linear concentration range could be extended to ca, five decades. The performance of the system was checked by analyzing a NIST 1643d reference material. Accuracy could be improved by the proper selection of the injected volume. Besides good precision (r,s.d, < 2%), the results obtained with the proposed procedure were closer to the certified values of the reference material than those obtained by direct aspiration or by injecting 125 mu L of several analytical solutions and samples.