Atomic Spectrometry Update: review of advances in elemental speciation

This is the 13 th Atomic Spectrometry Update (ASU) to focus on advances in elemental speciation and covers a period of approximately 12 months from December 2019. This ASU review deals with all aspects of the analytical atomic spectrometry speciation methods developed for: the determination of oxidation states, organometallic compounds, coordination compounds, metal and heteroatom-containing biomolecules, including metalloproteins, proteins, peptides and amino acids, and the use of metal-tagging to facilitate detection via atomic spectrometry. As with all ASU reviews, the focus of the research reviewed includes those methods that incorporate atomic spectrometry as the measurement technique. However, because speciation analysis is inherently focused on the relationship between the metal(loid) atom and the organic moiety it is bound to, or incorporated within, atomic spectrometry alone cannot be the sole analytical approach of interest. For this reason, molecular detection techniques are also included where they have provided a complementary approach to speciation analysis. This year the number of publications concerning As speciation remains similar to those covered last year, as do those for studies on Se speciation. The recent growth in work concerning Hg speciation has halted, although this is still a popular topic with the number of reports concerning Fe, halogen and sulfur speciation also rising. The number of elements covered this year reaches 30, showing the breadth of the elemental speciation field and how such work is now becoming more routine. This review covers advances in elemental speciation by a range of coupled techniques, including HPLC-ICP-MS, HPLC-HG-AFS and GC-ICP-MS.