Antibiotic-loaded chitosan-Laponite films for local drug delivery by titanium implants: cell proliferation and drug release studies.

In this study, chitosan-Laponite nanocomposite coatings with bone regenerative potential and controlled drug-release capacity are prepared by electrophoretic deposition technique. The controlled release of a glycopeptide drug, i.e. vancomycin, is attained by the intercalation of the polymer and drug macromolecules into silicate galleries. Fourier-transform infrared spectrometry reveals electrostatic interactions between the charged structure of clay and the amine and hydroxyl groups of chitosan and vancomycin, leading to a complex positively-charged system with high electrophoretic mobility. By applying electric field the charged particles are deposited on the surface of titanium foils and uniform chitosan films containing 25-55 wt% Laponite and 937-1655 µg/cm(2) vancomycin are obtained. Nanocomposite films exhibit improved cell attachment with higher cell viability. Alkaline phosphatase assay reveals enhanced cell proliferation due the gradual dissolution of Laponite particles into the culture medium. In-vitro drug-release studies show lower release rate through a longer period for the nanocomposite compared to pristine chitosan.