A proof of concept of a novel automatic sample cleanup approach for metal assays in troublesome matrixes as a front-end sample pre-treatment to inductively coupled plasma optical emission spectroscopy - ICP-OES - is herein presented. Target metals, namely, copper, lead, and cadmium were complexed in-system quantitatively using ammonium pyrrolidine dithiocarbamate (APDC) and transferred into a minute volume of toluene as extractant employing lab-in-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction (LIS-MSA-DLLME).
After discharge of the sample, the analytes were back-extracted into nitric acid and injected online into ICP-OES. To promote and expedite this process in-syringe, advantage was taken from oxidative decomposition of the chelate by potassium iodate, reported in this article for the first time.