Papers by Author: Tetsu Yonezawa

Abstract: We succeeded in determination the biodistribution of several nano-sized particles administered to mice through the tail vein. After administration, these particles were observed in the lung, liver and spleen. The distribution behaviors depend upon not only chemical species but also the particles size. To estimate their cytocompatibility, these particles were exposed to osteoblastic cell at several concentrations. When the concentration reached at 10 ppm, their viability remained at 80% or more even nano-sized particle contained rare earth element. Only CuO particles indicated the viability decrease. The effect depended on the particle size. These results suggested that the chemical species played a dominant key in the biodistribution and biocompatibility of nanoparticles compared with the size-effect.

Abstract: In this study, we succeeded in preparation and characterization of two types of biocompatible polymer-coated inorganic nanoparticles (cupper and silicone oxide). As a biocompatible polymer, gelatin and poly(lactic acid) were used. For determination of their biodistribution, the obtained particles were administered to mice through the tail vein. After administration, the particles in some organs were determined with energy-dispersed X-ray spectrometer. The cupper nanoparticles were observed in the lung and kidney, while the silica particles were in the lung, liver and spleen. The distribution behaviors were quite different from non-polymer coated nanoparticles