The Physical And Chemical Properties Of Nano Human Demineralized Bone Matrix Loading Recombinant Human Bone Morphogenetic Protein (rhBMP-2)

Objective: Preparation of nano allogeneic demineralized bone matrix graft substitutes loading rhBMP-2 material and research its physical and chemical properties.Methods: The human bones are gained from the total hip replacement surgery and the donors to be selected follow the provisions of the U.S. Association of Tissue Banks (AATB). The human demineralized bone matrixes (hDBM) are prepared by the method of modified Urist and produced by the MICROS for nano treatment then mixed with rhBMP-2 to get nano human demineralized bone matrix loading recombinant human bone morp-hogenetic protein-2(nhDBM-rhBMP-2) finally. The new materials were shaped by the vacuum freeze-drier to make the appropriate pores then sterilized by the 60Co radiation after sealed by two different packages: medical sterilization bags and bottles. The scanning electron microscopy, the X-ray fluorescence detector and the X-ray diffraction observation are used to test the new material. Finally, the heat of the original experiment, the acute systemic toxicity and the muscle implanted into rabbits are used to detect the biological properties of the new material.Results: This study was successfully prepared the nano human demineralized bone matrix loading the human bone morphogenetic protein -2 to make the nhDBM-rhBMP-2. Experiments confirmed that the new biological material in micro-nano structure is different from the hDBM and the calcium phosphate crystals. The particlediameter of the new material is less than 100nm, order rules, with appropriate porosities and C, O, N are the main elements in addition also includes: chlorine (Cl), sulfur (S), silicon (Si) and phosphorus (P) and metal elements: zirconium (Zr), Nickel (Ni), copper (Cu), iron (Fe), yttrium (Y), hafnium (Hf), calcium (Ca), potassium (K), aluminum (Al ) and chromium (Cr). So it is a multi-element composition of the organic mixture. The new material is non-toxic and pyrogen free. The rabbit muscle implantation test confirmed: 1 week after implantation the local tissue reaction was mild in the experimental group and has a small number of inflammatory cell infiltration. 8 weeks after implantation, inflammatory reaction is still less than the control group; after 12 weeks, there is no inflammatory reaction in experimental group. Experiments confirmed that glass bottles and bags of two different medical sterilization packaging materials are reliable and they can provide a good sterile environment.Conclusions: nhDBM-rhBMP-2 is non-toxic with good histocompatibilities and bioavailabilities. It is a low inflammation allogeneic bone graft substitute and has broad prospects and the development value. It Can be packaged with glass bottles and medical sterilization bags. Its biological activities and osteogenic properties also need to be further explored in subsequent experiments.