Evaluation of mechanical properties and hemocompatibility of open cell iron foams with polyethylene glycol coating

The increasing demand for improved implant biomaterials encourages their design and development. Degradable biomaterials have gained considerable attention especially in the past few decades. Metallic biomaterials are commonly applied in current medical practice to replace or repair diseased tissue. Structural materials with appropriate mechanical properties are required for load-bearing orthopedic applications. Moreover, biomaterials must fulfil the safety requirements and exhibit reasonable degradation rates to support the failing tissue and allow a gradual load transfer to the healing bone. Metal foams with open cell structure allow the transport of body fluids, growth of new tissues, improvement of degradation rate and reduction of the stress shielding phenomenon. In this work, iron open cell foams were fabricated by means of powder metallurgy processes. The hemocompatibility and mechanical properties of the porous iron materials without and with polyethylene glycol (PEG) coating were evaluated depending on the time of immersion in a simulated body fluid. It has been discovered, that PEG layer has increased the density and strength of iron foams. A mechanism of corrosion of iron foams with PEG coating layer was proposed. The suppression of hemolysis extension, platelet adhesion, and thrombus formation due to the polymer layer was observed as a result.