Determination of trace elements in fuel ethanol by ICP-MS using direct sample introduction by a microconcentric nebulizer

The use of a microconcentric nebulizer in ICP-MS is proposed to allow the introduction of ethanol solutions. High gas flow rate and low RF power led to less interference and high sensitivity. It was possible to introduce solutions with up to 70% v/v ethanol. The ethanol increases the nebulization efficiency and transport, with a sensibility gain between 15 and 25 for most studied analytes. External calibration allowed low detection limits, adequate for fuel ethanol analysis. The Cu, Cd, Ni, Pb, T1 and Sn concentrations determined by isotope dilution were in accordance with those by external calibration. The precision was adequate, with RSD from 1 to 9% using external calibration with IS, and the recovery test showed the accuracy of the proposed method.