Page 59 - Magnesium-based supports for stem cell therapy of vascular disease - Mónica Echeverry Rendón

NOVEL COATINGS FOR COMMERCIAL PURE MAGNESIUM OBTAINED BY PLASMA ELECTROLYTIC OXIDATION THROUGH THE ADDITION OF ORGANIC ADDITIVES
breakdown voltage and the density and intensity of the sparks decreased, all these effects contribute to the compact characteristic of the anodic film obtained. Oppositely, by the addition of hexamethylenetetramine and mannitol, porous surfaces were obtained in a process high influenced by the gas evolution on the interface coating-electrolyte. - In general, at higher voltage/current applied, higher size porous (for NAF and MAN) and higher thickens of the coatings. Uniformity and thickness of the coatings depends directly of the charge applied and the mode operation. - Potentiostaic mode showed better results in terms of homogeneity and distribution of porous because in this pro- cesses a lower charge was used in comparison with galvanostatic mode.
- PEO is a simples, low cost and reproducible technique that allow the surface modification of Mg in which nontoxic and environmental friendly solutions are used. This is a good option to be used for modification of implants in bio- medical fields.
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