Preparation of SiO2-Protecting Metallic Fe Nanoparticle/SiO2 Composite Spheres for Biomedical Application

Materials

Pin-Wei Hsieh¹  Ching-Li Tseng²  Dong-Hau Kuo¹ 

[1] Department of Materials Science and Engineering, National Taiwan University of Science and Technology, No. 43, Sec. 4, Keelung Road, Taipei 10607, Taiwan;;Graduate Institute of Biomedical Materials and Tissue Engineering, College of Biomedical Engineering, Taipei Medical University, No. 250, Wu-Hsing Street, Taipei 110, Taiwan

关键词: metallic iron;    SiO₂;    nanoparticle;    magnetic property;    drug carriers;   

DOI  :  10.3390/ma8115416

来源: mdpi

【 摘 要 】

Functionalized Fe nanoparticles (NPs) have played an important role in biomedical applications. In this study, metallic Fe NPs were deposited on SiO₂ spheres to form a Fe/SiO₂ composite. To protect the Fe from oxidation, a thin SiO₂ layer was coated on the Fe/SiO₂ spheres thereafter. The size and morphology of the SiO₂@Fe/SiO₂ composite spheres were examined by transmission electron microscopy (TEM). The iron form and its content and magnetic properties were examined by X-ray diffraction (XRD), inductively-coupled plasma mass spectrometry (ICP-MS) and a superconducting quantum interference device (SQUID). The biocompatibility of the SiO₂@Fe/SiO₂ composite spheres was examined by Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) tests. The intracellular distribution of the SiO₂@Fe/SiO₂ composite spheres was observed using TEM. XRD analysis revealed the formation of metallic iron on the surface of the SiO₂ spheres. According to the ICP-MS and SQUID results, using 0.375 M FeCl₃·6H₂O for Fe NPs synthesis resulted in the highest iron content and magnetization of the SiO₂@Fe/SiO₂ spheres. Using a dye loading experiment, a slow release of a fluorescence dye from SiO₂@Fe/SiO₂ composite spheres was confirmed. The SiO₂@Fe/SiO₂ composite spheres co-cultured with L929 cells exhibit biocompatibility at concentrations <16.25 µg/mL. The TEM images show that the SiO₂@Fe/SiO₂ composite spheres were uptaken into the cytoplasm and retained in the endosome. The above results demonstrate that the SiO₂@Fe/SiO₂ composite spheres could be used as a multi-functional agent, such as a magnetic resonance imaging (MRI) contrast agent or drug carriers in biomedical applications.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.