Comparison of the in vitro bioactivity and drug release property of mesoporous bioactive glasses (MBGs) and bioactive glasses (BGs) scaffolds

Three-dimensional (3D) porous MBGs and BGs scaffolds have been prepared by using polyurethane sponge as the template. The structure and morphology of both scaffolds were characterized by X-ray diffraction, scanning electron microscopy. transmission electron microscopy and N-2 adsorption-desorption technique. Both scaffolds have the interconnected macroporous network with pore diameter of 300-500 mu m. However, the MBGs scaffold has the mesoporous walls with mesopore size of 4.8 nm, and exhibits higher surface area and pore volume. The in vitro bioactivities of both scaffolds were studied by scanning electron microscopy and Fourier-transform infrared spectroscopy. The results indicated that the MBGs scaffold has a faster hydroxylcarbonate apatite (HCA) formation rate on the surface than the BGs scaffold. Using gentamicin as the model drug, the MBGs scaffold can load over twofold higher amount of drug than the BGs scaffold. The results of the in vitro release in SBF showed that the gentamicin release rate from the MBGs scaffold is much lower compared to that from the BGs scaffold. Therefore, the MBGs scaffold might be used as a local drug delivery system for bone tissue regeneration. (C) 2008 Elsevier Inc. All rights reserved.