Room temperature synthesis of chitosan/apatite powders and coatings

Bioactive chitosan/apatite powders and adherent coatings have been synthesized by a co-precipitation method and an alkaline transformation at room temperature. Powders with organic/inorganic ratios ranging from 42 to almost 90% can be prepared in substantial amounts. This method allows to coat Ti6Al4V substrates yielding films with thicknesses of approximately 1 μm that show an adhesion strength superior to 15 MPa. The coating procedure can be repeated to increase the thickness of the layer. The formation of apatite onto these materials after immersion in a simulated body fluid (SBF) indicates a potential bioactivity in vivo. The materials have been characterized by viscosimetry, XRD, FTIR, SEM, EDS and TG/ATD. The adhesion strength was determined by a pull-out test.