In Vitro Evaluation of Silicon-Containing Apatite Fiber Scaffolds for Bone Tissue Engineering

Abstract

The aim of the present investigation was to examine Si release from the silicon-containing apatite fiber scaffold (Si-AFS) and the biocompatibility of the Si-AFS. We have successfully synthesized silicon-containing apatite fibers (Si-AF) by a homogenous precipitation method. Three-dimensional Si-AFS were fabricated using these Si-AFs. The concentrations of Si in the starting solution were 0 (AF) and 0.8 (0.8Si-AF) mass%. The 0.8Si-AFS1000 were fabricated by firing Si-AF slurry compacts (carbon/Si-AF [w/ ratio: 10/1) at 1300 °C for 5 h. Solubility experiments were carried out in 0.05 mol/dm3 Tris-HCl buffer solutions at pH 7.30 using 0.8Si-AFS1000 (porosity: ~98%), together with Si-free AFS1000 (~98%) for 21 days. The Ca2+, PO43- and SiO44- concentrations in the solution were determined by inductively-coupled plasma atomic emission spectrometry (ICP-AES). The biocompatibility of the Si-AFS was examined in vitro using osteoblastic cell, MC3T3-E1 for 21 days. The results of the ICP-AES analysis indicated that the amount of SiO44- ions released from 0.8Si-AFS1000 rapidly increased at 1 day, and then the released SiO44- ions remained constant over a period for 21 days. The cells seeded on/in the 0.8Si-AFS1000 well-proliferated as compared to those on/in the AFS1000. Consequently, we can conclude that the 0.8Si-AFS offers as a potential novel scaffold material, creating a three-dimensional cell culture environment.