The broadening scope of JAAS

The aim of this editorial is to consider the changing role of atomic spectrometry and how that role should influence the scope of papers published in JAAS. The issue seems to reduce to how “atomic” JAAS should remain and still reflect developments in areas of interest to those who practise atomic spectrometry. A prime example is in the life sciences. Speciation is particularly important in the life sciences: further, speciation by its nature has always been positioned at the interface between atomic and molecular spectroscopy—techniques that should be viewed as complementary rather than competitive.

Another example related to speciation can be found in mass spectrometry. The borderline between traditional inorganic (ICP) and biomolecular (electrospray and MALDI) mass spectrometry is becoming less well defined; ICP-MS is now being used widely in the field of proteomics, and electrospray MS is becoming a key tool in elemental speciation analysis. Further, applications in the life sciences require multi-method analytical approaches in which atomic spectrometry plays an important role; many techniques are needed to understand the complex processes of life.

A final example can be found in the burgeoning field of “ambient mass spectrometry”. In this field, the goal is to identify and determine constituents in solid, liquid, or gaseous samples, but with the samples merely positioned in the laboratory environment near a source/mass spectrometer combination. Ordinarily, the resulting mass spectrum is a molecular one: however, “atomic” sources such as glow discharges, dielectric-barrier discharges and coronas are frequently used. Consequently, the developers of such plasma sources are often known mainly for their work in atomic spectrometry.

A related issue is whether the purview of JAAS should remain within the customary metallic elements or instead expand to include the entire periodic table. After all, commonly used “elemental analyzers” take care of elements such as carbon, nitrogen, sulfur, and phosphorus, and there has never seemed to be a need for JAAS to cover them, unless they happened to be among a broader list of elements.

Again, a lesson might be taken from the life sciences. Most elements play a role in life processes, and all elements in the periodic table can be (and are) detected and quantified by atomic spectrometry. As the sensitivity of atomic spectrometry and the level of contamination have been improved, an increasing number of elements has been found to be essential. Further, the main constituents of nucleic acids and proteins are the non-traditional elements carbon, hydrogen, nitrogen, sulfur, and phosphorus. If metalloproteins or nucleic-acid complexes are to be determined by atomic spectrometry, does it not make perfect sense to determine these other important elements at the same time? And is the analysis then not appropriate for publication in JAAS?

Another critical issue in life sciences is post-translational modification of a protein. One of the most important such modifications is phosphorylation, and it is not surprising that phosphorus can most sensitively be measured by ICP-MS. An example can be found in the article by Ana Pereira Navaza, Jorge Ruiz Encinar and Alfredo Sanz-Medel in issue 10 of JAAS 2007 entitled ‘Quantitative protein phosphorylation analysis: the role of ICP-MS’.

Of course, “metallomics” is an important part of this picture. In this context, metallomics is the structural and functional characterization of metal-binding biomolecules and, to a certain extent, can include the characterization of the entirety of metal and metalloid species within a biosystem (for instance in a cell or even in a complex tissue sample). This topic has become an important focus in JAAS; indeed, there have already been two special issues of JAAS devoted to it. Also, JAAS has established a new metallomics and biological elemental speciation web page, which collects recent papers on these topics that have been published in the journal. Papers, Technical Notes and Reviews are all included, enabling you to see what the present challenges are and what direction the area may take in the future. With links to other biologically relevant web pages of the RSC, including discussion groups, this is a unique tool for keeping you up to date with work in this field. For information about this and other exciting developments read the Editorial from Niamh O’Connor, Editor of JAAS, and Gary Hieftje (DOI: 10.1039/b718165p).

From the foregoing considerations it now seems that “metallomics” might be too restrictive a term. For instance, the expression of a metalloprotein, detected by means of its concentration and also of the metal associated with it, is an important quantitative measure that can be achieved by atomic spectrometry. Yet this measure indicates nothing about the activity or status of the protein, which might be controlled by post-translational modification. As a result, we should not measure the metal only but also phosphorus and potentially other non-metallic elements. A more suitable term might therefore be “elementomics”, which is nothing else but biological elemental speciation.

“Elementomics” seems highly appropriate for JAAS. For instance, the halogens are often used as tags in biochemistry, and JAAS is just now organizing a special issue for “Elemental Tags and Detectors for Proteomics”. Anyone interested in contributing to this issue should contact the Reviews Editor (Norbert Jakubowski) as soon as possible.

These arguments suggest that JAAS should be an interface that brings together organic and inorganic, atomic and molecular spectrometry. Some time ago, the famous analytical chemist Charles N. Reilley defined “analytical chemistry” as “… what analytical chemists do”. In a similar fashion, we can assert that “atomic spectrometry” is what atomic spectrometrists do. Does this mean that JAAS will print even articles which are fully molecular? Yes, JAAS will—if the authors can point out why their topic is related to “elementomics” or “metallomics” or that an “atomic” source was used in the molecular method. Once the focus of an article is related to an element that is of interest to the JAAS readership, a publication in this journal is justified. Analysis of sulfur-, selenium- and phosphorus-containing proteins, metal-complexes with nucleic acids, carbohydrates and proteins, metal-tagged biomolecules and many others are topics that have already been published in JAAS. Similarly, JAAS will welcome papers that describe novel plasma sources used for ambient mass spectrometry or other molecular detection techniques, or microplasmas that might not atomize an incoming sample but only ionize or excite it, or in novel uses of traditionally atomic sources.

A few other examples might help clarify. Polyphenols are not ordinarily described in JAAS, except where their metal-binding capability is of interest to JAAS readers. Sugars are not in the scope of JAAS, but once the binding of selenium or arsenic is involved then the subject is appropriate for the journal. Similarly, alcohols are not at all within the scope of JAAS, nor is the detection of silicon as a tag for alcohols if it is detected via GC-MS. But if ICP-MS is employed for detection the whole story changes. Thus, the suitability of a paper for JAAS depends on the hetero-element, the source, the detector, the method … and on the reader’s point of view.

In summary, if, as an author, you have good arguments then the journal is open for your article. If you are not sure, please send your article and we (the Editorial Board) will let you know in a few days if your article is within the journal’s scope.

Think big, think broad, think elemental.

Norbert Jakubowski

ISAS—Institute for Analytical Sciences, P. O. Box 10 13 52, D-44013 Dortmund, Germany. E-mail: jakubowski@isas.de

Gary M. Hieftje

Department of Chemistry, A150 Chemistry Building, Indiana University, Bloomington, IN 47405, USA. E-mail: hieftje@indiana.edu

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