Association of osteogenic proteins in biominerals and metallic oxides doped with rare-earth: interaction with membrane models systems

Abstract

Over the last years the development of biomaterials for bone regeneration has increased in order to improve not only their mechanical properties, but also to improve the integration ability of the implant to the body. As a result, efforts are directed in order to mimic the chemical composition and structure of the natural tissues. In this sense, this project aims at the synthesis of bioactive and osteo inductive materials based on different nanoparticles, such calcium and strontium phosphates and carbonates, as well as zinc, titanium and zirconium oxides, with the association of their morphology, structure, and chemical composition to their biological response. In addition, osteogenic proteins will be adsorved on the particles surfaces and also into the matrix used for biomineral formation, in order to improve their biological response. The particles will be synthesized using either polycarbonate membranes as a template or by hydro (solvo) thermal methods. After morphologic and spectroscopic characterization, the surface properties will be evaluated by contact angle measurements in order to evaluated the wettability and surface free energy of the samples. The bioactivity of the particles will be investigated through their exposure as colloidal dispersions in Simulated Body Fluid (SBF). The viability of osteoblastic cells in the presence of synthesized particles will be studied. The influence of the surface properties of the nanoparticles in the presence and absence of adsorved osteogenic proteins will be evaluated using cell membrane model systems, such as Langmuir monolayers and Langmuir-Blodgett films. The incorporation of rare-earth ions into the particles will be useful to study the nanoparticles incorporation in the model systems as well as to explore their application as biological probes using spectroscopic techniques. We expect in this research to deeply understand the biomineralization process and also to obtain new biomaterials which act as accelerators in the proliferation of bone cells by a synergism between their structure and morphology also related to their optical and biological properties. (AU)