Page 85 - Magnesium-based supports for stem cell therapy of vascular disease - Mónica Echeverry Rendón

STERILIZATION PROCEDURES IMPACT PURE MAGNESIUM MODIFIED BY PLASMA ELECTROLYTIC OXIDATION
The anodized samples were analyzed by AFM to assess the morphology of the coating and its roughness. The Rq was 166.0±10.4 nm Fig.2.
Fig.2 AFM pictures (122.5x122.5μm scans) of the Mg surfaces anodized.
Once the materials were anodized, these were sterilized and the composition of the coatings analyzed by XRD and EDS.
Additionally, the EDS analysis indicated as expected that in addition to magnesium and oxygen, Si was present too in a lower fraction (12-15%). The silicate ions (SiO32-) get incorporated from the electrolyte into the film during anodiza- tion, under the effect of the electric field and facilitated with the formation of channels in the anodic film, thanks to the occurrence of sparks. The only variation observed in the chemical composition of the treated surfaces was an increment of the oxygen content for the sample exposed to UV radiation.
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Fig.3 XRD patterns of samples sterilized by different methods. Untreated sample (A), steam autoclaved (B), dry-heat (C), UV-radiation (D) and formaldehyde (E).
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