Manufacture and characteristics of HA-Electrodeposited polylactic acid/polyvinyl alcohol biodegradable braided scaffolds

摘要

This study proposes the braided bone scaffolds. First, biologically degradable polylactic acid (PLA) filaments and polyvinyl alcohol (PVA) filaments are plied into composite yarns using a doubling and twisting machine. The composite yarns are tested to determine the optimal mechanical properties and a stabilized morphology. The PLA/PVA composite yarns are then braided into bone scaffolds, during which the optimal braiding process parameters and yarn ratio are determined. Based on the surface observation and tensile strength, a gear ratio of 45:45 provides the tubular braids with an optimal morphology and porosity that meet the biological requirements. When the PLA/PVA ratio is 3:1, the braids exhibit the maximum tensile properties and the most stable space structure. Furthermore, to make the braids a bioactive material with surface active sites, the braids are coated with hydroxyapatite (HA) by electrodeposition. The resulting HA-electrodeposited bone scaffolds are tested by in vitro biological experiments using a scanning electronic microscope (SEM), energy dispersive x-ray analysis(EDAX), X-ray Diffraction(XRD), and Fourier transform infrared spectroscopy(FT-IR), thereby examining their characteristics and microstructure. Results suggest that HA is electrodeposited over the bone scaffolds successfully. The immersion in simulated body fluid (SBF) is proven to contribute a good in vitro bioactivity to bone scaffolds. As a result, bone scaffolds are a good candidate for the application in the cancellous bone repairing field.