Electrophoretic deposition of bioactive glass/polymer composite coatings with and without HA nanoparticle inclusions for biomedical applications

Electrophoretic deposition (EPD) methods have been developed for the fabrication of composite bioactive glass-hydroxyapatite (HA)-chitosan and bioactive glass-HA-alginate composite coatings. TWO different strategies have been utilized, which are based on the use of cationic chitosan and anionic alginate biopolymers. The mechanism of cathodic deposition of chitosan is based on the pH increase at the cathode surface, whereas the pH decrease at the anode surface enabled the deposition of alginate coatings. The use of chitosan and alginate enabled the electrosteric stabilization and deposition of bioactive glass and HA particles. Composite coatings were obtained on various conductive substrates and studied by thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The composition of the coatings can be varied by variation of bioactive glass and HA concentrations in the suspensions. The proposed method offers the advantages of room temperature fabrication of bioactive composite coatings that are suitable for biomedical applications. (C) 2008 Elsevier B.V. All rights reserved.