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As a measure of the prevention of implant associated infections, a number of strategies have been recently applied. Silver-containing materials possessing antibacterial activity as expected might have wide applications in orthopedics and dentistry. The present work focuses on the physico-chemical characterization of silver-containing hydroxyapatite (Ag-HA) coating obtained by radio frequency (RF) magnetron sputtering. Mechanochemically synthesized Ag-HA powder (Ca10-xAgx(PO4)(6)(OH)(2-x), x = 1.5) was used as a precursor for sputtering target preparation. Morphology, composition, crystallinity, physico-mechanical features (Young's modulus and nanohardness) of the deposited Ag-HA coatings were investigated. The sputtering of the nanostructured multicomponent target at the applied process conditions allowed to deposit crystalline Ag-HA coating which was confirmed by XRD and FTIR data. The SEM results revealed the formation of the coating with the grain morphology and columnar cross-section structure. The EDX kanalysis confirmed that Ag-HA coating contained Ca, P, O and Ag with the Ca/P ratio of 1.6 +/- 0.1. The evolution of the mechanical properties allowed to conclude that addition of silver to HA film caused increase of the coating nanohardness and elastic modulus compared with those of pure HA thin films deposited under the same deposition conditions.

Fragestellung: Humane mesenchymale Stammzellen (hMSC) stellen aktuell die vielversprechendste Zellpopulation in der regenerativen Medizin dar. Calciumphosphat (CaP) spielen eine wichtige Rolle bei der Knochenregeneration und Silber (Ag) gewinnt bei der Behandlung von Infektionen wegen zunehmender Antibiotikaresistenzen[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2015)

The nanoparticles of Na⁺,CO₃²⁻-containing hydroxyapatites have been prepared from aqueous solutions for system Na⁺-Ca²⁺-NO₃⁻-CO₃²⁻-PO₄³⁻ at molar ratio of Ca/P = 1.67:1 and CO₃²⁻/PO₄³⁻ = 0, 1.0, 2.0, 3.0. Thermal transformations of the obtained phosphates have been established for the temperature range of 80-900°C. The obtained complex-substituted HAP have been investigated using IR spectroscopy, scanning electron microscopy, X-ray diffraction and thermogravimetry.

A series of nanostructured low-crystalline hydroxyapatite (HA) coatings averaging 170, 250, and 440 nm in thickness were deposited onto previously etched titanium substrates through radio-frequency (RF) magnetron sputtering. The HA coatings were analyzed using infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM and TEM). Cross sections of the thin specimens were prepared by FIB to study the microstructure of the coatings by TEM. The deposition process formed nano-scale grains, generating an amorphous layer at the substrate/coating interface and inducing the growth of a columnar grain structure perpendicular to the substrate surface. A microstructural analysis of the film confirmed that the grain size and crystallinity increased when increasing the deposition time. The nanostructured HA coatings were not cytotoxic, as proven by in vitro assays using primary dental pulp stem cells and mouse fibroblast NCTC clone L929 cells. Low-crystallinity HA coatings with different thicknesses stimulated cells to attach, proliferate and form mineralized nodules on the surface better than uncoated titanium substrates.