Y(III) ion substituted 2D anionic clay (I); in-vitro cytotoxicity and intercellular uptake behavior

Abstract Radiotherapeutic yttrium-90 (Y-90) is known to be a pure β-emitter with few environmental radiation restrictions, and therefore, it is considered to be suitable for use in the irradiation of large solid tumors due to its high energy (2280 keV) and long particle traveling range (12 mm). To develop a novel radio-therapeutic system based on Y-90, we have prepared nonradioactive Y(III) incorporated hydrotalcite nanoparticles (YHN) as the proof of concept. Confirmed as a drug delivery carrier, hydrotalcite nanoparticles (HN) with the size of ~100 nm could target not only tumor tissues but also tumor cells due to their superior intercellular permeability thanks to the clathrin-mediated endocytosis. Therefore, YHN, [Mg2.17Al0.89Y0.11(OH)6.34(CO3)0.5∙nH2O], was prepared by co-precipitation method and by subsequent hydrothermal treatment. The as-prepared YHN was determined to have an average size of ~100 nm with a plate-like morphology, and their cellular uptake efficiency in the mouse liver cancer cells was found to be 2.5 times higher than that in the normal ones. The YHN showed very low cytotoxicity with no significant decrease in cell proliferation at the concentration below 100 μg/mL, implying that the present YHN could potentially be used in theranostic applications.