Quantitative and microautoradiographic study on mouse intestinal distribution of polycyanoacrylate nanoparticles

Abstract Polyhexyl-[3- 14 C]cyanoacrylate nanoparticles were perorally administered to mice. After 90 min, 4, 8, 24, 48 h, and 6 days the animals were killed and the intestine was divided into 24 sections. The radioactivity distribution between neighbouring sections in individual animals was very irregular and could vary by up to a factor of 1000. The overall distribution, however, was more homogeneous with a distinct accumulation in the sections before the ileo-cecal junction after 90 min and in the cecum after longer time periods. The amount of radioactivity dropped to 30–40% of the 90 min value within 4–8 h and to 5% 24 h after dosing. Radioactivity (0.04%) was still detectable after 6 days. Histological investigations revealed radioactivity adjacent to the brush border, inside goblet cells, and in muscle cells up to 6 days after administration. The histological analysis also gave evidence that labelled material was translocated to the circulation.