**4. Conclusion**

Electrophoretic impregnation of porous anodizing layer elaborated in phosphoric acid was executed in aqueous TiO<sup>2</sup> nanoparticles suspension. It should be noted that impregnation process is conditioned by the applied electric field. Applying high electric field (200 V/cm) induces the jellification of TiO<sup>2</sup> sol because of the anodic electrolysis of water which decreases the pH near the electrode surface and then destabilizes the suspension against coagulation at low pH. In order to avoid this phenomenon and facilitate the insertion of titanium dioxide nanoparticles, the addition of the glycine to buffer the suspension is necessary. At the beginning of EPD, particles go to the bottom of pores which continue to fill progressively.

These results attest that EPD can be used to fill successfully porous anodizing layer despite the presence of the resistive barrier layer at the metal-oxide interface.
