Assessment of Pharmacokinetics, Toxicity, and Biodistribution of a High Dose of Titanate Nanotubes Following Intravenous Injection in Mice: A Promising Nanosystem of Medical Interest.

Titanate nanotubes (TiNTs) produced by the static hydrothermal process present a promising nanosystem for nanomedicine. However, the behavior of these nanotubes in vivo is not yet clarified. In this work, for the first time, we investigated the toxicity of these materials, their pharmacokinetic profile, and their biodistribution in mice. A high dose of TiNTs (45 mg/kg) was intravenously injected in mice and monitored from 6 h to 45 days. The histological examination of organs and the analysis of liver and kidney function markers and then the inflammatory response were in agreement with a long-term innocuity of these nanomaterials. The parameters of pharmacokinetics revealed the rapid clarification of TiNTs from the bloodstream after 6 h of the intravenous injection which then mainly accumulated in the liver and spleen, and their degradation and clearance in these tissues were relatively slow (>4 weeks). Interestingly, an important property of these materials is their slow dissolution under the lysosome acid environment, rendering them biodegradable. It is noteworthy that TiNTs were directly eliminated in urine and bile ducts without obvious toxicity in mice. Altogether, all these typical in vivo tests studying the TiNT pharmacokinetics, toxicity, and biodistribution are supporting the use of these biocompatible nanomaterials in the biomedical field, especially as a nanocarrier-based drug delivery system.