Characterization of Iron Core–Gold Shell Nanoparticles for Anti-Cancer Treatments: Chemical and Structural Transformations During Storage and Use
Ya-Na Wu,
Dar-Bin Shieh,
Li-Xing Yang,
Hwo-Shuenn Sheu,
Rongkun Zheng,
Pall Thordarson,
Dong-Hwang Chen,
Filip Braet
Affiliations
Ya-Na Wu
Institute of Oral Medicine and Department of Stomatology, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan 70101, Taiwan
Dar-Bin Shieh
Institute of Oral Medicine and Department of Stomatology, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan 70101, Taiwan
Li-Xing Yang
Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 70101, Taiwan
Hwo-Shuenn Sheu
National Synchrotron Radiation Research Center, Hsinchu Science-Based Industrial Park, Hsinchu 30076, Taiwan
Rongkun Zheng
Australian Centre for Microscopy & Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
Pall Thordarson
School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
Dong-Hwang Chen
Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
Filip Braet
Australian Centre for Microscopy & Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
Finding a cancer-selective drug that avoids damaging healthy cells and organs is a holy grail in medical research. In our previous studies, gold-coated iron (Fe@Au) nanoparticles showed cancer selective anti-cancer properties in vitro and in vivo but were found to gradually lose that activity with storage or “ageing„. To determine the reasons for this diminished anti-cancer activity, we examined Fe@Au nanoparticles at different preparation and storage stages by means of transmission electron microscopy combined with and energy-dispersive X-ray spectroscopy, along with X-ray diffraction analysis and cell viability tests. We found that dried and reconstituted Fe@Au nanoparticles, or Fe@Au nanoparticles within cells, decompose into irregular fragments of γ-F2O3 and agglomerated gold clumps. These changes cause the loss of the particles’ anti-cancer effects. However, we identified that the anti-cancer properties of Fe@Au nanoparticles can be well preserved under argon or, better still, liquid nitrogen storage for six months and at least one year, respectively.