Evaluations of osteogenic and osteoconductive properties of a non-woven silica gel fabric made by the electrospinning method

Evaluations of the osteoblast-like cell responses and osteoconductivity of a non-woven silica gel fabric were carried out to determine its potential for application as a scaffold material for use in bone tissue engineering. The silica gel solution was prepared by condensation following hydrolysis of tetraethyl orthosilicate under acidic conditions. The solution was spun under a 2 kV cm(-1) electric field. The diameters of the as-spun silica gel fibers were in the range of approximately 0.7-6 mu m. The fabric was then heat-treated at 300 degrees C for 3 h. The proliferation of pre-osteoblastic MC3T3-E1 cells evaluated by the NITS assay was lower than on the tissue culture plate (TCP) as many cells leaked through the large voids formed by the randomly placed long, narrow silica gel fibers, which further retarded cell growth. However, the expressions of extracellular signal-regulated kinase and transcriptional factor from the cells were higher when cultured on the non-woven silica gel fabrics than on TCP. The alkaline phosphatase (ALP) activity and differentiation marker expressions assessed by amplication via the reverse transcription-polymerase chain reaction, such as type I collagen, ALP and osteocalcin, were higher for cells cultured on non-woven silica gel fabrics than on TCP. The non-woven silica gel fabric showed good osteoconductivity in the calvarial defect New Zealand white rabbit model. To this end, the non-woven silica gel fabric has good potential as a scaffold material for bone tissue engineering due to its good biological properties. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.