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Various types of biodegradable polymers containing lactide, glycolide, caprolactone, and trimethylene carbonate units have been used to obtain ciprofloxacin (CFX)enriched coatings developed on the Ti6Al7Nb alloy, intended for short-term therapy.In the first step, the surface of the Ti6Al7Nb alloy was modified, mostly according to sandblasting and anodic oxidation to obtain the TiO 2 layer. Anodizing can be an effective method for preparing TiO 2 coatings with osteoconductive properties. The polymer containing CFX molecules was deposited on the modified alloy, and Polymer + CFX/TiO 2 /Ti6Al7Nb systems were developed. CFX-enriched coatings adhered well to the surface of the previously modified alloy. Polymer layers maintain the topography of the alloy due to the development of the surface during the sandblasting method. As polymers intended for the study possess degradation ability, they are capable of releasing the incorporated drug. Antibacterial activity of CFX-enriched coatings was examined to verify the functionality of designed Polymer + CFX/TiO 2 / Ti6Al7Nb systems, and the bactericidal effect was confirmed for all cases. The presented study is an extension of previous, initial research and creates an overview of polyester or polyestercarbonate CFX-eluting coatings. K E Y W O R D Sciprofloxacin, drug delivery, implants, polyester, Ti6Al7Nb

The aim of this study was to determine the influence of long-term exposure of Ringer’s solution on degradation of the anodically oxidated Ti6Al4V alloy coated with a biodegradable polymer coating. Polymeric coatings made of poly(glycolide-ε-caprolactone) – G-Cap and poly(glycolide- ε-caprolactone-lactide) – G-Cap-L were applied by a dip-coating method. Degradation was assessed on the basis of the results of pitting corrosion resistance and density of metal ions infiltrating to the solution. Studies were conducted for samples after 3, 6, 8, 10 and 12 weeks of exposure to the corrosive environment. In addition, topography of the surface of the polymer coating was assessed. As a result of potentiodynamic studies, the value of the polarization resistance and corrosion potential for the G-Cap and G-Cap-L coated samples were significantly decreased while simultaneous reduction of the density of metal ions infiltrating to the solution throughout the whole study period. There was also observed a faster degradation of the G-Cap coating compared to G-Cap-L, which showed local discontinuity after 12 weeks of exposure. The obtained results provide the basis for the development of polymeric coatings on surface of metal implants with predictable time / kinetics of degradation by selecting the composition of polymers while simultaneous limitation of metal ions infiltration into surrounding tissues.

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The aim of the study was to determine the influence of long term exposure to Ringer's solution of biodegradable polymer coatings containing an active substance on the Ti6Al7Nb alloy substrate on the physical and chemical properties of the coatings and the degradation process of the metal substrate. The studies used poly(L-lactide-co-trimethylene carbonate) P(L/TMC), poly(L-lactide-co-trimethylene carbonate-glycolide) P(L/TMC/G) and poly(D,L-lactide-glycolide) (PLGA) coatings applied to the anodically oxidized Ti6Al7Nb alloy by means of dipping method (1, 2 and 3 dips). The polymer coatings contained ciprofloxacin. Roughness and wettability tests were carried out on the substrate and polymer coatings, the pitting corrosion resistance of the substrate and samples with polymer coating was determined, the number of metallic ions released to the solution from the coated and uncoated samples was determined as well as the adhesion of polymer coatings. The research was supplemented by microscopic observations. The results of the research indicate different influence of exposure to Ringer's solution on the physical and chemical properties of biodegradable polymer coatings containing ciprofloxacin and the course of the degradation process of the metal substrate.

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EvaluatIoN of corrosIoN rEsIstaNcE of tItaNIuM alloys usEd for MEdIcal IMplaNtsThe study presents the results of investigations of modeling the usable properties of implant surfaces made of Ti6Al7Nb alloy, using the example of a dynamic hip screw (DHS) applied in surgical treatment of intertrochanteric femoral neck fractures. Numerical simulation has been performed for the model load of femoral fixation with DHS screw. The load simulation results provided the basis to select mechanical properties of the fixator elements and to define those fixation areas which are mostly susceptible to development of corrosion. The surfaces of Ti6Al7Nb alloy were ground, vibro-abrasive machined, mechanically polished, sandblasted, anode oxidized at different voltage values and steam sterilized. Results of surface topography evaluation, resistance to pitting and crevice corrosion as well as degradation kinetics of the outer layer were presented. Usability of the formed passive layer in clinical applications was evaluated through wear and corrosion tests of the femoral fixation model. The test results proved usefulness of the proposed surface modification methods for clinical application of different size and shape implants

The study discusses the methods of surface modification methods for AISAI 316 L steel and Ti6Al4V ELI titanium alloy, dedicated to complex design implants used in bone surgery. Results of structural tests have been presented along with those evaluating the physicochemical properties of the formed surface layers. Clinical feasibility of the surface layers has also been evaluated.The developed surface modification methods improved the resistance to pitting, crevice and stress corrosion and ensured better biocompatibility. Moreover, the layers formed are marked by plasticity. Results of the tests performed show applicability of the evaluated methods of surface modification in complex shape implants for the clinical use.Keywords: AISI 316L stainless steel, Titanium alloy Ti6Al4V, Surface layer, Corrosion and wear resistance, Biocompatibility.W pracy omówiono metody modyfikacji powierzchni stali AISAI 316 L oraz stopu tytanu Ti6Al4V ELI przeznaczonych na implanty o złożonej konstrukcji stosowanych w chirurgii kostnej. Przedstawiono wyniki badań struktury oraz własności fizykochemicznych wytworzonych warstw wierzchnich. Określono również przydatność wytworzonych warstw do zastosowań klinicznych.Opracowane metody modyfikacji powierzchni zwiększyły odporność na korozję wżerową, szczelinową i naprężeniową oraz poprawiły biokompatybilności. Ponadto wytworzone warstwy cechują się podatnością do odkształceń. Wyniki badań wykazały przydatność zastosowanych metod modyfikowania powierzchni implantów o złożonych kształtach do zastosowań klinicznych.remodeling, ensuring long-term therapeutic effect. An major issue is also the quality of the implant surface layer. Studies carried out by the leading research centres are focusing now on modification of the implant surface with layers or coats adhering well to the metallic base, deformable during preoperative modeling and ensuring plastic, cyclic deformation upon use. The surface of the biomaterial should show high resistance to different types of corrosion (pitting, crevice, stress, wear) as well as biocompatibility. Such properties are ensured by carbon coatings formed on steel AISI 316L implants. The coatings are obtained with the use of a variety of technologies so that consequently their structure and properties may be shaped. We differentiate between hydrogen carbon coatings (a-C:H) and hydrogen free ones (a-C). The latter are obtained through magnetron sputtering, arch sputtering or laser ablation. The carbon coatings, on the other hand, are produced by decomposition of hydrocarbons through PACVD procedures. Depending on the production