Distribution and accumulation of 177Lu-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles in the tissues of ICR mice

Abstract

To investigate kinetics of free 177Lu and 177Lu-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION), suspensions were intravenously injected into the tail vein of mice at a dose of 5 μCi/mouse or 15 mg/kg body weight, respectively. Free 177Lu radioactivity levels were highest in kidney followed by liver and lung 1 day post-injection. 177Lu-labeled TCL-SPION radioactivity in liver and spleen was significantly higher compared to that of other organs throughout the experimental period (p < 0.05). Radioactivity in blood, brain, and epididymis rapidly declined until 28 days. Based on these results, TCL-SPION could be a safe carrier of therapeutics.