Fate of 14C-terpolymer (methylmethacrylate-14C, 2-hydroxyethylmethacrylate, butylacrylate) nanoparticles after peroral administration to rats.

The fate of 14C-terpolymer (methylmethacrylate-14C, 2-hydroxyethylmethacrylate, butylacrylate) nanoparticles was studied in male Wistar rats after peroral administration. These nanoparticles may reach systemic circulation as evidenced by the plasma 14C level, excretion of the label in the urine, as well as organ label deposition. It was found that at least 2% of the dose of 14C was absorbed from the gastrointestinal tract. As expected, the radioactive nanoparticles were excreted predominantly via the feces. The amount of the label in the gastrointestinal tract, liver, and carcasses fell below the limit of detection on day seven after administration. However in the spleen and lung some slight radioactivity persisted after 7 d of experiment.