ABSTRACT
Abstract This study developed and characterized a method for controlled deposition of thin films of hydroxyapatite on titanium surfaces. Thirty-three titanium cylinders were randomly divided: negative control/polished (A), acid etched (B) and coated by hydroxyapatite (C). Acid etch was performed in an aqueous solution of nitric acid. The cylinders were subjected to coating by a thin film of hydroxyapatite with dip-coating method. These cylinders were submitted to a pre-heat treatment 450°C/10 minutes and 800°C/2 hours. Scanning electron microscopy analysis demonstrated a homogeneous and smooth surface (A), an irregular and porous surface (B) and a crystalline deposition (C). The X-ray energy dispersive analysis showed characteristic elements of hydroxyapatite (C). Analysis by X-ray diffraction showed the presence of characteristic peaks of hydroxyapatite, corresponding to the structural composition of hydroxyapatite. Cell viability (MTT-assay in NIH-3T3-Cells) test demonstrated no differences between the groups. Titanium surfaces coated with a hydroxyapatite film by the dip-coating method suggest adequate control of deposition of thin films of hydroxyapatite and similar cell viability using mouse fibroblasts.
ABSTRACT
Alginate hydrogel (AH) has intrinsic physical and biological limitations that hinder its broader application in tissue engineering. We hypothesized that the inclusion of nanofibers in the hydrogel and the use of a biotemplate that mimics nature would enhance the translational potential of alginate hydrogels. In this study, we have shown a method to obtain nano-/microfibers of titanium (nfTD) and hydroxyapatite (nfHY) using cotton as a biotemplate. These fibers were incorporated in the alginate hydrogel and the mechanical characteristics and biological response to these reinforced materials were evaluated. We observed that these nanofibers resembled the structure of natural collagen and did not mediate cell toxicity. The incorporation of nfTD or nfHY to the AH has not increased the viscosity of the hydrogel. Therefore, this is a feasible method to produce a scaffold with improved physical characteristics, while at the same time generating an enhanced environment for cell adhesion and proliferation.
