Bioactivity, Pre-Osteoblastic Cell Responses, and Osteoconductivity Evaluations of the Electrospun Non-Woven SiO2-CaO Gel Fabrics

Abstract

The evaluations of the fibers characteristics, bioactivity, pre-osteoblastic cell responses, and osteoconductivity of the non-woven SiO2–CaO gel fabric made by electrospinning method was carried out. Silica gels with four different calcium contents were prepared by condensation following hydrolysis of tetraethyl orthosilicate under acidic conditions. The molar ratios of Ca to Si prepared ranged from 0 to 0.15. SiO2–CaO gel fabrics were heattreated at 3008C for 3 h after spinning under an electric field of 2 kV/cm. As the Ca to Si ratio increased, the diameter of electrospun SiO2–CaO gel fibers increased because the viscosity of the SiO2–CaO gel solution increased. The apatite-forming ability of heat-treated, non-woven SiO2–CaO gel fabric was evaluated in simulated body fluid and tended to increase with an increasing Ca to Si molar ratio. However, proliferation and differentiation tended to decrease with an increasing Ca to Si molar ratio. The sample which had the Ca to Si ratio as 0.10 showed good osteoconductivity in vivo in the calvarial defect New Zealand white rabbit model compared to that had the Ca to Si ratio as 0 and empty defect. These results strongly suggest that non-woven SiO2–CaO gel fabric made by the electrospinning method has potential for application as a bone grafting material.