Application of new covalently-bound diglycolamide sorbent in sequential injection analysis flow system for sample pretreatment in ICP-MS determination of ²³⁹Pu at ppt level

Diglycolamide ligands are widely applied in the analysis of radionuclides, especially lanthanides and actinides. They are used in liquid-liquid extraction procedures or in solid-phase extraction sorbents where they are adsorbed on the surface of hydrophobic polymers. The main objective of this study was to synthesize the N,N,N'N'-tetrahexyl diglycolamide with one vinyl terminating group (vTHDGA) for further covalent immobilization on the polystyrene-divinylbenzene polymeric support. The obtained complexing resin (THDGA) was employed for the mechanized sample pretreatment in the Sequential Injection Analysis - Lab-on-Valve (SIA-LOV) flow system for the determination of ²³⁹Pu using ICP-MS detection. The analytical procedure was optimized in terms of selectivity towards several other radionuclides and elements forming potentially isobaric interferences in mass spectrometry. For 100 mL volume of sample to be analyzed, the method detection limit (MDL) was 96 mBq L^-1 (42 pg L^-1). The developed method was employed for the determination of ²³⁹Pu in real samples of a nuclear reactor coolant and spent fuel pool water from a nuclear reactor.