Atomic Spectrometry Update–Atomic mass spectrometry

Abstract

The format of this year's Update follows that used last year¹ with some minor changes in the section headings. Although an attempt is made to consider all relevant refereed papers, conference abstracts, reports, book chapters and patents for inclusion, this review does not attempt to be comprehensive in its coverage. Critical selection is based on criteria which have been applied more strictly this year than in previous years in order to focus more sharply on the most significant developments reported during the period (approximately corresponding to 1997) covered by this Update. The prime consideration is that the reports should present advances in instrumentation and methodology or improved understanding of the fundamental processes involved in the MS process. As a general rule, conference abstracts are not included because they rarely provide sufficient information to judge whether or not they meet the criteria. We consider it better to wait for full details to appear in a refereed journal. A similar policy applies to those papers in a language other than English and unlikely to reach a wide readership.

Routine applications of atomic MS are not covered in this Update and readers are referred to the Updates on Industrial Analysis: Metals, Chemicals and Advanced Materials,² Environmental Analysis³ and Clinical and Biological Materials, Food and Beverages.⁴ An additional review that can be recommended is that of Moens⁵ on applications of MS in the analysis of biological materials. Comprehensive evaluations of MS techniques for the analysis of solid samples have been reported by Gijbels and Bogaerts⁶ and Becker et al.⁷

Papers included in this Update must be on atomic spectrometry but some areas of study introduce problems in defining atomic and molecular studies. One of the major drives in recent years has been to develop methods for speciation studies, in particular using ESMS, GC-MS or ICP-MS. The study, for example, of organic arsenic species by ICP-MS involves MS of the atomic ions but in ESMS and GC-MS the molecular species are usually detected. In general, studies of 'exotic' nuclei far from stability are excluded but the determination of radioactive elements in 'real' samples can be included. Very few measurements in SIRMS are of atomic species, yet the object of measuring natural isotopic composition is to study or use a fundamental atomic property. Such studies are included but the use of enriched spikes in tracer studies are excluded because the focus of the study is not on the atomic properties of the tracer element.

The strong progress being made in most areas of atomic MS is evident from the different sections of this Update. The various trends have been identified in each section and range from the continued improvements in sample preparation for TIMS analysis of remarkable sensitivity and precision to the demand for simpler and cheaper AMS instrumentation so that applications to biomedical research can be fully exploited. Much attention continues to be given to sample preparation and introduction for ICP-MS, in particular for speciation analysis, yet relatively little effort is being given to instrumental development. Although SIMS and SNMS are widely used techniques, fundamental problems remain for quantification and work continues on developing methodologies to optimize analyses.