gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2018)

23.10. - 26.10.2018, Berlin

Bimetallic silver-platinum nanoparticles: antimicrobial effect and cell activation of human mesenchymal stem cells

Meeting Abstract

  • presenting/speaker Marina Breisch - BG Universitätsklinikum Bergmannsheil, Chirurgische Forschung, Chirurgische Klinik und Poliklinik, Bochum, Germany
  • Viktoria Grasmik - Universität Duisburg-Essen, Anorganische Chemie, Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany
  • Kateryna Loza - Universität Duisburg-Essen, Anorganische Chemie, Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany
  • Matthias Epple - Universität Duisburg-Essen, Anorganische Chemie, Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany
  • Marc Heggen - Forschungszentrum Jülich, Ernst-Ruska-Centrum, Elektronenmikroskopie und Elektronenspektroskopie, Jülich, Germany
  • Thomas A. Schildhauer - BG Universitätsklinikum Bergmannsheil, Chirurgische Forschung, Chirurgische Klinik und Poliklinik, Bochum, Germany
  • Manfred Köller - BG Universitätsklinikum Bergmannsheil, Chirurgische Forschung, Chirurgische Klinik und Poliklinik, Bochum, Germany
  • Christina Sengstock - BG Universitätsklinikum Bergmannsheil, Chirurgische Forschung, Chirurgische Klinik und Poliklinik, Bochum, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2018). Berlin, 23.-26.10.2018. Düsseldorf: German Medical Science GMS Publishing House; 2018. DocPT19-945

doi: 10.3205/18dkou693, urn:nbn:de:0183-18dkou6932

Veröffentlicht: 6. November 2018

© 2018 Breisch et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objectives: Silver (Ag) is a well-known antimicrobial agent against a broad spectrum of bacteria. The antimicrobial effect of Ag is caused by an oxidative silver ion (Ag+) release. Efforts are made to increase the biocompatibility of Ag application by a rapid and time-limited Ag+ release. This can be achieved by silver nanoparticles (Ag-NP) due to their high specific surface area or a combination of Ag with an electrochemically more noble metal, such as platinum (Pt) generating a sacrificial anode effect. Recently, we demonstrated the efficiency of a sacrificial anode approach (Köller et al., 2017). Here, we present the combination of both methods by synthesis of bimetallic AgPt-NP and analysis of antimicrobial activity against S.aureus and E.coli as well as effects on human mesenchymal stem cells (hMSC).

Methods: PVP-coated Ag-, Pt- and AgPt-NP of different metal composition (diameter 10 nm) were synthesized by reducing AgNO3 and H2PtCl6 with NaBH4 or citrate/tannin. Transmission Electron Microscopy and Energy Dispersive X-ray Spectroscopy were used to examine the NP microstructure. The antimicrobial activity of the NP was analyzed by determination of the minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC). The viability, the morphology and the proliferation of hMSC exposed to NP were analyzed by calcein-AM staining and the AlamarBlue Assay. The differentiation of hMSC into osteogenic lineage was examined by Alizarin Red S staining.

Results and conclusion: Pure Ag-NP and AgPt-NP with at least 70% Ag showed a significant concentration and time dependent antimicrobial effect against S.aureus and E.coli as well as toxicity towards hMSC. The hMSC toxicity of AgPt-NP compared to pure Ag-NP was lower after 24 h and became comparable during long term exposure. Therefore, no sacrificial anode effect could be observed. Pure Pt-NP exhibited neither an antimicrobial effect nor a hMSC toxicity. Furthermore, AgPt-NP with at least 50% Pt and pure Pt-NP led to cell nodule formation associated with inhibited cell proliferation. An osteogenic differentiation was not observed, but the presence of osteogenic differentiation medium (ODM) led to an enhanced hMSC mineralization.

AgPt-NP and pure Ag-NP showed comparable antimicrobial and cell toxic effects, indicating that an enhanced Ag+ release was not achieved by this system. This can be explained by the presence of both alloyed and Ag-core-Pt-shell AgPt-NP, as revealed by microstructure analysis. Since the efficiency of a sacrificial anode system was already shown (Köller et al., 2017), further work is needed to obtain NP with a Pt-core-Ag-shell microstructure.

Long term exposure to AgPt-NP with at least 50% Pt and pure Pt-NP led to cell nodule formation, while the presence of ODM enhanced the hMSC calcification. Therefore, small Pt containing NP might be useful as osteo-promotive supplement for biomaterials.