Actinides selective extractants coated magnetite nanoparticles for analytical applications

N , N , N ′, N ′-tetraoctyl diglycolamide (TODGA) and bis(2-ethylhexy)phosphoric acid (HDEHP) were coated on Fe 3 O 4 nanoparticles under different chemical conditions. The TODGA-coated magnetite nanoparticles (Fe 3 O 4 @TODGA) captured representative actinides Am(III) and Pu(IV) at 3–4 M HNO 3 with high efficiency. However, the HNO 3 induced pre-organization of TODGA, before coating on the magnetite nanoparticles, was found to be important for the sorption of Am(III) and Pu(IV) ions. The Fe 3 O 4 @HDEHP particles exhibited selectivity toward Pu(IV), and Am(III) did not sorb from 3 to 4 M HNO 3 . The quantification of Pu(IV) preconcentrated on coated particles was carried out by removing the extractant coating in dioxane based scintillator, followed by liquid scintillation counting.