Yanxia Zheng,Gang Dong,Liyong He,Gang Wu,Huade Zheng,Chunlin Deng
Calcium phosphate layers, which are widely applied on the surface of biomaterials, are important for improving tissue regeneration performance. The composition of layers formed on the surface of biomaterials differs depending on the soaking fluid. Herein, revised simulated blood fluid and fast calcification solution were investigated as immersing solutions for the mineralization of hydroxyapatite ceramics. The morphology of the hydroxyapatite particles and precipitate formation on the hydroxyapatite ceramics surface were characterized by transmission electron microscopy . Furthermore, scanning electron microscopy was used to examine the morphology of the bioactive ceramics surface. The structure of the layers was determined by selected-area electron diffraction. The prepared hydroxyapatite powders were characterized by powder X-ray diffraction. The results showed that hydroxyapatite was preferentially formed on the hydroxyapatite ceramics surface in revised simulated blood fluid and octacalcium phosphate precipitated in fast calcification solution. Additionally, the content of HCO 3 - in the mineralization fluid strongly influenced the crystal phase composition and morphology of the calcium phosphate layers on the bio-ceramics materials studied herein.
Polyvinyl alcohol/silica (PVA/SiO 2 ) hybrid fibers were prepared via a sol–gel combined electrospinning technique, and their potential application in bone tissue engineering was evaluated in terms of in vitro bioactivity. When the PVA concentration was 8%, the obtained PVA/SiO 2 hybrid fibers exhibited a uniform and continuous morphology, with an average fiber diameter of about 542.9 nm. The SiO 2 xerogel phase was uniformly distributed within the PVA matrix, and its actual content was very close to the theoretical value. After 3 days of immersion in simulated body fluid (SBF), the PVA/SiO 2 hybrid fibers displayed a vigorous precipitation of lamellar apatite crystals, reflecting their excellent in vitro bioactivity.