Electroanalysis overview: The determination of the poisoner's poison, thallium

In this overview, we explore the electroanalytical determination of the poisoner's poison: thallium. Thallium was named after the Greek word "thallos," meaning "green shoot" or "twig," due to its bright green spectral emission lines. It is toxic, tasteless, odourless and dissolves into water, and has been used by murderers as a challenging poison to detect and there is the need for the analytical determination of thallium. Laboratory based analytical instrumentation provide a routine methodology to measure thallium, but there is scope to develop in-the-field analytical measurements that are comparable to laboratory equipment and in some cases, they can provide even more sensitive analytical approaches. Electrochemistry can support such endeavours, where instrumentation are readily portable where electroanalytical sensors provide highly selective and sensitive outputs but yet are economical to support on-site analysis. In this review, we provide an electroanalytical overview of the current research directed toward the measurement of thallium and offer insights to future research.