In Vivo Biodistribution and Toxicity of Highly Soluble PEG-Coated Boron Nitride in Mice

The boron nitride (BN) nanoparticles, as the structural analogues of graphene, are the potential biomedicine materials because of the excellent biocompatibility, but their solubility and biosafety are the biggest obstacle for the clinic application. Here, we first synthesized the highly soluble BN nanoparticles coated by PEG (BN-PEG) with smaller size (similar to 10 nm), then studied their biodistribution in vivo through radioisotope ((TcO4-)-O-99m) labeling, and the results showed that BN-PEG nanoparticles mainly accumulated in the liver, lung, and spleen with the less uptake by the brain. Moreover, the pathological changes induced by BN-PEG could be significantly observed in the sections of the liver, lung, spleen, and heart, which can be also supported by the test of biochemical indexes in serum. More importantly, we first observed the biodistribution of BN-PEG in the heart tissues with high toxicity, which would give a warning about the cardiovascular disease, and provide some opportunities for the drug delivery and treatment.