| AVS 54th International Symposium | |
| Biomaterial Interfaces | Tuesday Sessions |
| Session BI-TuP |
| Session: | Biomaterials Interfaces Poster Session |
| Presenter: | S. Fujita, Nagoya University, Japan |
| Authors: | S. Fujita, Nagoya University, Japan T. Ishizaki, Nagoya University, Japan N. Saito, Nagoya University, Japan O. Takai, Nagoya University, Japan |
| Correspondent: | Click to Email |
1. Introduction Nanoparticles of metal alloy, metallic oxides, semiconductors and ceramics have unique properties compared with bulk materials since they have high reactivity and catalysis by the large specific surface area. Thus, nanoparticles have been paid attention in the various fields and utilized as electric devices, biomedical materials and cosmetics. On the other hand, it has been reported that nanoparticles could have a harmful effect on human body. For example, nanoparticles such as soot in exhaust fumes are inhaled into lung and cause pulmonary and cardiac diseases. In some recent researches, it is reported that nanoparticles could activate an adverse reaction in the body because they pass through cell walls and move through the blood or lymph vessel. However, nobody knows their interactions with the body in detail. In this study, we aimed to investigate the influence of the nanoparticles on the cell growth and assess the risk of nanoparticles. 2. Experimental procedure Au, Pt, and Ag nanoparticles were synthesized by a wet reduction process. Citric acid was used as a reducing agent. Mouse fibroblast cells (NIH-3T3) were cultured in medium (DMEM, pH: 7) containing the nanoparticles in humidified atmosphere containing 5.0% CO2 at 37°C for 3 days. The cultured cells were counted using blood cell counting chamber and observed with phase-contrast microscope and transmission electron microscope (TEM). 3. Result Only Ag nanoparticles prevented the cells from growing onto the culture dish. Number of cells after the culture for 72 hours decreased with the increase of concentration of Ag nanoparticles. TEM images showed that the Ag nanoparticles were engulfed into a cell tissue. In addition, the ingested Ag nanoparticles were aggregated around the nuclear. However, such aggregation is not the reason that the cell cannot be cultured in the medium containing Ag nanoparticles, because Au and Pt nanoparticles were also aggregated around the nuclear. At least, Ag nanoparticles are toxic to cells. We believe that nanoparticles may provide us many types of risk; damage of DNA, disappear of proteins and so on. We must investigate the mid- and long-term influence of the nanoparticles on human being.