Fundamental studies of mixed gas plasmas in ICP-MS
type: CreativeWork
description: Inductively coupled plasma - mass spectrometry is widely accepted as the leading technique for trace element analysis. It suffers however, from a range of interferences both spectral and non - spectral which limit the range of analytes and substrates which may be successfully analyzed. This study has investigated the use of mixed gas plasmas as a means of reducing or removing these interference effects. In addition the use of mixed gas plasmas for sensitivity enhancement has been assessed using both wet and dry sample introduction systems. Simplex optimization procedures have been used throughout. The addition of nitrogen to all three argon gas flows of the ICP was evaluated, and the instrumental operating conditions were optimized to allow for the maximum removal of the ArCl+ interference on As and Se. The addition of nitrogen to the nebulizer gas was particularly effective in the removal of the ArCl+. The use of nitrogen addition also facilitated the determination of arsenic in samples where it was previously found to be impossible. The addition of methane was also applied to all three gas flows of the ICP, however, in this case only the addition to the nebulizer gas was successful in removing interferences. These included ArO+, ClO+ and CeO+ in addition to ArCl+ . Detection limits, recoveries and CRM analysis were all improved by the use of methane addition when compared to nitrogen addition or standard argon plasmas. Hydrogen addition was applied solely to the nebulizer gas and found to significantly increase the magnitude of the interferences from argon based polyatomic ions, whilst reducing those from metal oxides. The addition of hydrogen was useful in reducing MO+ interferences, but the removal of other interferences proved unsuccessful. The addition of ethene to the nebulizer gas has been used to remove many of the polyatomic interferences encountered in ICP-MS, including those based on Na, S and P. Ethene addition was as effective as, and usually better th…
abstract: Inductively coupled plasma - mass spectrometry is widely accepted as the leading technique for trace element analysis. It suffers however, from a range of interferences both spectral and non - spectral which limit the range of analytes and substrates which may be successfully analyzed. This study has investigated the use of mixed gas plasmas as a means of reducing or removing these interference effects. In addition the use of mixed gas plasmas for sensitivity enhancement has been assessed using both wet and dry sample introduction systems. Simplex optimization procedures have been used throughout. The addition of nitrogen to all three argon gas flows of the ICP was evaluated, and the instrumental operating conditions were optimized to allow for the maximum removal of the ArCl+ interference on As and Se. The addition of nitrogen to the nebulizer gas was particularly effective in the removal of the ArCl+. The use of nitrogen addition also facilitated the determination of arsenic in samples where it was previously found to be impossible. The addition of methane was also applied to all three gas flows of the ICP, however, in this case only the addition to the nebulizer gas was successful in removing interferences. These included ArO+, ClO+ and CeO+ in addition to ArCl+ . Detection limits, recoveries and CRM analysis were all improved by the use of methane addition when compared to nitrogen addition or standard argon plasmas. Hydrogen addition was applied solely to the nebulizer gas and found to significantly increase the magnitude of the interferences from argon based polyatomic ions, whilst reducing those from metal oxides. The addition of hydrogen was useful in reducing MO+ interferences, but the removal of other interferences proved unsuccessful. The addition of ethene to the nebulizer gas has been used to remove many of the polyatomic interferences encountered in ICP-MS, including those based on Na, S and P. Ethene addition was as effective as, and usually better th…
author: Ford, Michael John
language: eng
date published: 1993-01-01T08:00:00Z
date modified: 2026-07-24T03:49:07Z
provider: University of Plymouth
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Plymouth