Synthesis and Characterization of Citrate-Stabilized Gold-Coated Superparamagnetic Iron Oxide Nanoparticles for Biomedical Applications
René Stein,
Bernhard Friedrich,
Marina Mühlberger,
Nadine Cebulla,
Eveline Schreiber,
Rainer Tietze,
Iwona Cicha,
Christoph Alexiou,
Silvio Dutz,
Aldo R. Boccaccini,
Harald Unterweger
Affiliations
René Stein
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Bernhard Friedrich
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Marina Mühlberger
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Nadine Cebulla
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Eveline Schreiber
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Rainer Tietze
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Iwona Cicha
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Christoph Alexiou
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Silvio Dutz
Institute of Biomedical Engineering and Informatics, Technische Universität Ilmenau, 98693 Ilmenau, Germany
Aldo R. Boccaccini
Institute of Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen, Germany
Harald Unterweger
Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum, 91054 Erlangen, Germany
Surface-functionalized gold-coated superparamagnetic iron oxide nanoparticles (Au-SPIONs) may be a useful tool in various biomedical applications. To obtain Au-SPIONs, gold salt was precipitated onto citrate-stabilized SPIONs (Cit-SPIONs) using a simple, aqueous one-pot technique inspired by the Turkevich method of gold nanoparticle synthesis. By the further stabilization of the Au-SPION surface with additional citrate (Cit-Au-SPIONs), controllable and reproducible Z-averages enhanced long-term dispersion stability and moderate dispersion pH values were achieved. The citrate concentration of the reaction solution and the gold/iron ratio was found to have a major influence on the particle characteristics. While the gold-coating reduced the saturation magnetization to 40.7% in comparison to pure Cit-SPIONs, the superparamagnetic behavior of Cit-Au-SPIONs was maintained. The formation of nanosized gold on the SPION surface was confirmed by X-ray diffraction measurements. Cit-Au-SPION concentrations of up to 100 µg Fe/mL for 48 h had no cytotoxic effect on Jurkat cells. At a particle concentration of 100 µg Fe/mL, Jurkat cells were found to take up Cit-Au-SPIONs after 24 h of incubation. A significantly higher attachment of thiol-containing L-cysteine to the particle surface was observed for Cit-Au-SPIONs (53%) in comparison to pure Cit-SPIONs (7%).
