Synthesis and characterization of bioactive glasses functionalized with Cu nanoparticles and organic molecules

Bioactive sol gel glasses, based on the ternary system 15CaO·5P2O5·80SiO2, doped with Cu were synthesized and characterized in order to define the oxidation state of Cu as a function of thermal treatments. In particular, we were able to optimize the condition to obtain: (i) the reduction of Cu2+ to Cu0 followed by nano-aggregation of metal nano-particles (MeNPs) into glass matrix; (ii) a mixed Cu2+/Cu+/Cu0 NPs-containing glasses; (iii) a Cu2+-containing glasses.Successively, the surface of sol–gel glasses was functionalized by means of organic molecules (amino and mercapto alcohols) to give rise to a system that can interact with the functional groups of the drugs. The functionalization was carried out as a function of the sol–gel glass composition, organic molecules concentration and temperature of the process; the results indicate a preference for the amino groups. The bioactivity (formation of an apatitic layer after simulated body fluid SBF test) was verified for the functionalized sol–gel Cu2+-containing glasses and they are still bioactive.