Sintered metallic foams for biodegradable bone replacement materials

The iron open cell foams were synthesized by the replication method based on powder metallurgical technologies as biodegradable bone replacement material. Open cell metal foams provide extraordinary combinations of the properties. Samples containing carbon nanotubes (CNTs) and Mg were produced with the aim to affect degradation rate and enhance the biocompatibility. The microstructure, corrosion behaviour and in vitro biocompatibilities were investigated by scanning electron microscopy, immersion tests in Hank’s solution during the time of 8 weeks, cytotoxicity and haemolysis tests. The addition of CNTs and Mg induced the higher surface inhomogeneity and roughness, which was more pronounced for Fe–Mg sample. The homogenous degradation on the whole surface was registered for bare iron sample, while progressive local corrosion sites were found on the surface of samples with CNTs and Mg. Highest corrosion rate was determined for Fe–Mg sample which came to be disintegrated after 3 weeks of immersion. The slowest degradation rate was detected for Fe–CNTs sample. The fast dieback of fibroblast cells was registered under static conditions in monolayer cell culture. However, all the experimental samples were found to be highly haemocompatible. Additionally, the haemolysis percentage value of about 2 % determined for Fe–Mg sample proved its good performance for blood vessel related cellular application.