Quo vadis high-resolution continuum source atomic/molecular absorption spectrometry?

Abstract

After more than a decade since its commercial introduction, high-resolution continuum source atomic/molecular absorption spectrometry may be facing a mid-life crisis. Certainly, it is no longer a novel technique full of unknown potential, so it would already be time to establish the fields for which it is most suitable. This is, however, not so simple for a number of reasons. In the first place, more than a technique what we are discussing herein is a type of instrumentation with the potential to use two different techniques (atomic or molecular absorption), making it somewhat unique. Furthermore, the two techniques have not been explored equally, and more research on the mechanisms of formation of diatomic molecules is clearly needed. In the second place, new possibilities have recently appeared in the literature that need to be weighed as well. And there is the still unfulfilled, but nowadays more technically feasible than ever, promise to significantly increase the multi-elemental capabilities. This review critically examines the main research areas currently explored (namely, (i) direct analysis of solids and complex liquid materials, and (ii) determination of non-metals at trace levels via monitoring of molecular species) as well as the new venues (specifically, (i) isotopic analysis via monitoring of molecular species, and (ii) selective detection, quantification and sizing of nanoparticles) while also considering new instrumental developments, in an attempt to properly place high-resolution continuum source atomic/molecular absorption spectrometry in the field of trace element and isotopic analysis.