Ultrasensitive determination of inorganic arsenic by hydride generation-atomic fluorescence spectrometry using Fe3O4@ZIF-8 nanoparticles for preconcentration

In this work, magnetic Fe3O4@ZIF-8 core-shell nanoparticles (MNPs) were employed for effective adsorption of inorganic arsenic for preconcentration, with adsorption mechanism thoroughly discussed. The adsorbed inorganic arsenic was easily separated by a magnet along with the MNPs from the sample matrix, with possible matrix interference eliminated. The MNPs were then completely dissolved in hydrochloric acid prior to the determination of inorganic arsenic by hydride generation-atomic fluorescence spectrometry. The Fe3O4@ZIF-8 MNPs were prepared with a facile step-by-step assembly method in aqueous solution at room temperature. Under the optimized conditions, the sensitivity for inorganic arsenic determination was significantly increased through preconcentration, with satisfactory analytical merits obtained.