Tough, Strong and Resorbable Orthopaedic Implants - GoIMPLANT

Project summary

The aim of the project is to develop resorbable, tough, strong and biocompatible hybrid composite implants meeting patients needs. The mechanical strength of proposed composite materials will reach 270 MPa, fracture toughness more than 1 MPa•m1/2 and they will be resorbable in a time up to 24 months. The present materials of choice for implants are titanium alloys or stainless steel, which frequently require to be removed in a second operation. This is an additional risk and cost for patients. Resorbable implants are currently made from polymers. Their mechanical strength is not satisfactory, and inflammatory processes are a significant risk factor. The new implants will conquer a large fraction of the market of orthopaedic implants, which will reach 250 billion euro in 2015 . The key success factors of this project are three innovative technologies: synthesis technology of Calcium Deficient Hydroxyapatite Nanoparticles (CDNHAP), technology to produce hybrid nano composite granules form PLA polymer and CDNHAP, and Ultra-High Pressure Warm Isostatic Compaction (UHPWIC). The CDNHAP nanoparticles developed by us are exceptionally bio-compatible. Preliminary test have shown that they are also non-toxic to test cells. The synthesis process relies on precisely controlling the hydrothermal synthesis time in a high power microwave reactor, with precision of 30 sec. Further, we developed a granulation method, where the PLA molecules are tightly bonded with the HAP nanoparticles during the granules formation process. The method will be further improved using a freeze granulation process, to ensure scale up of the production. Finally, the granules will be compacted into 100% dense bulk hybrid nanocomposites under pressures up to 1 GPa at a temperature up to 450K. The temperature will be adjusted to prevent PLA decomposition. The technology will permit to obtain hybrid nanocomposites with nano-HAP content from 50% up to 95%, depending on the specific orthopaedic application. The compaction conditions will be optimised, so that during densification the bio-compatible nanostructure is preserved. As a consequence, high strength will be combined with ductility. The project partners already filled several patents to protect the CDNHAP technology and the granules formation technology. The CDNHAP powder was registered under the trade name GoHAP. Further patents will be filled. These measures are taken to accelerate the technology commercialisation.