Determination of trace elements in serum by dynamic reaction cell inductively coupled plasma mass spectrometry - Developing of a method with a desolvating system nebulizer

An inductively coupled plasma mass spectrometer (ICP-MS), equipped with a dynamic reaction cell (DRC) and coupled with a desolvating nebulizing system (Apex-ACM) to reduce the oxide formation, was used in the determination of Al, Co, Cr, Mn, Ni and Se in serum samples. The effect of the operating conditions of the DRC system was studied to get the best signal-to-background (S/B) ratio. The potentially interfering molecular ions at the masses m/z(27)Al, Co-59, Cr-52, Mn-55, Ni-60 and Se-78, were significantly reduced in intensity by using NH3 and H-2, as the reaction cell gases in the DRC, while a proper Dynamic Bandpass Tuning parameter q (RPq) value was optimized. The detection limits for Al-27, Co-59, Cr-52, Mn-55 Ni-60 and Se-71, estimated with 3-sigma method, resulted to be 0.14, 0.003, 0.002, 0.01, 0.01 and 1.8 mu g L-1, respectively. This analytical method was developed on both a human serum certified reference material and a lyophilized animal serum produced and proposed in an intercomparison study. The results obtained for the reference samples agreed satisfactorily with the certified values. Precision (expressed as CV%) between sample replicates was better than 10% for elements determination, with the only exception of aluminium (14%). (c) 2006 Elsevier B.V. All rights reserved.