• LIFANG ZHANG

Articles written in Bulletin of Materials Science

• Fabrication and characterization of PDLLA/pyrite composite bone scaffold for osteoblast culture

A series of highly interconnected porous poly(D,L-lactide acid) (PDLLA)/pyrite (Zi-Ran-Tong, FeS2) scaffold containing 5–20% of pyrite was fabricated by particle leaching combined with the thermal-induced phase separation method. Pyrite (FeS2, named as Zi-Ran-Tong in Chinese medicine), as a traditional Chinesemedicine, has been used in the Chinese population to treat bone diseases and to promote bone healing. The mechanical properties of the PDLLA scaffold were significantly enhanced after the addition of pyrite. The osteoblastic ROS17/2.8 cell line was used and seeded on the PDLLA/pyrite scaffold to study its potential to support the growth of osteoblastic cells and to estimate the optimal dose of pyrite for bone tissue engineering. The effects of pyrite on cell proliferation and differentiation were evaluated by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide and alkaline phosphatase activity assay. The cells on the porous composite scaffold formed a continuous layer on the outer and inner surface observed by scanning electron microscopy and fluorescence microscope. The results strongly suggested that the PDLLA/pyrite composite scaffold could stimulate the growth of ROS17/2.8 cells in vitro and it could be potentially used as a scaffold for bone tissue engineering.

• In vitro bioactivity evaluation of $\alpha$-calcium sulphate hemihydrate and bioactive glass composites for their potential use in bone regeneration

To combine the self-setting property of $\alpha$-calcium sulphate hemihydrate ($\alpha$-CSH) with the bioactive property of bioactive glass (BG), BG was added into $\alpha$-CSH to prepare $\alpha$-CSH/BG composites. The in vitro bioactivity and cytocompatibility of the $\alpha$-CSH/BG composites were assessed by soaking the composites in simulated body fluid (SBF) andco-culturing with the osteoblasts, respectively. Formation of a bone-like apatite layer on the composite surface was studied by X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM) andenergy-dispersive spectroscopy (EDS). Variations in ionic concentration and pH of the SBF solution were detected. The incorporation of BG into $\alpha$-CSH, effectively compensated for the pH decrease caused by the dissolution of $\alpha$-CSH and the ion exchange.Osteoblast-like cells (MG63) were cultured on the samples, and theMTTresults confirmed that the compositescontaining BG were more favourable for the proliferation of these cells. Hence, $\alpha$-CSH/BG composites might have great potential for the use as a bone regeneration material.

• # Bulletin of Materials Science

Current Issue
Volume 42 | Issue 3
June 2019