Yanovska G. Physicochemical features of calcium phosphates coating formation onto titanium an magnesium model implants

The thesis is devoted to investigation of the processes of calcium-phosphate coatings formation on titanium and magnesium model substrates from aqueous solutions. Physicochemical approaches were developed for handling of such processes and the way of their practical use is proposed. Surface modification of substrates by oxygen ion implantation and chemical pretreatment by solutions NaOH, HF, H2O2 was applied for improvement adhesion of hydroxyapatite coating to the substrate surface. The increasing of coating formation and adhesion strength after chemical pretreatment is shown. Chitosan was introduced into the hydroxyapatite (HA) coatings for adhesion improvement and silver was introduced for antimicrobial properties. It was shown that "HA-Ag" coatings, which obtained on modified by chitosan film substrate, have more expressed antimicrobial activity to the strain of E. coli. Coatings based on brushite and hydroxyapatite was obtained on Mg substrates by dipping of substrates in working solutions with various composition in isothermal conditions. The influence of permanent magnetic field (0,3 T), namely the proximity to the north and the south magnetic poles and the presence of Mg on crystal texture of calcium phosphates (brushite) was also investigated.