In vitrobiocompatibility of 45S5 Bioglass^®-derived glass-ceramic scaffolds coated with poly(3-hydroxybutyrate)

Abstract

The aim of this work was to study the in vitro biocompatibility of glass-ceramic scaffolds based on 45S5 Bioglass, using a human osteosarcoma cell line (HOS-TE85). The highly porous scaffolds were produced by the foam replication technique. Two different types of scaffolds with different porosities were analysed. They were coated with a biodegradable polymer, poly(3-hydroxybutyrate) (P(3HB)). The scaffold bioactivity was evaluated by soaking in a simulated body fluid (SBF) for different durations. Compression strength tests were performed before and after immersion in SBF. These experiments showed that the scaffolds are highly bioactive, as after a few days of immersion in SBF a hydroxyapatite-like layer was formed on the scaffold's surface. It was also observed that P(3HB)-coated samples exhibited higher values of compression strength than uncoated samples. Biocompatibility assessment was carried out by qualitative evaluation of cell morphology after different culture periods, using scanning electron microscopy, while cell proliferation was determined by using the AlamarBlue assay. Alkaline phosphatase (ALP) and osteocalcin (OC) assays were used as quantitative in vitro indicators of osteoblast function. Two different types of medium were used for ALP and OC tests: normal supplemented medium and osteogenic medium. HOS cells were seeded and cultured onto the scaffolds for up to 2 weeks. The AlamarBlue assay showed that cells were able to proliferate and grow on the scaffold surface. After 7 days in culture, the P(3HB)-coated samples had a higher number of cells on their surfaces than the uncoated samples. Regarding ALP- and OC-specific activity, no significant differences were found between samples with different pore sizes. All scaffolds containing osteogenic medium seemed to have a slightly higher level of ALP and OC concentration. These experiments confirmed that Bioglass/P(3HB) scaffolds have potential as osteoconductive tissue engineering substrates for maintenance and normal functioning of bone tissue.

Preparation and Characterization of Gallium Releasing 3‐D Alginate Coated 45S5 Bioglass® Based Scaffolds for Bone Tissue Engineering

“…[55,56] In the present scaffolds of very high porosity the addition of the Ga-alginate coating enhanced the mechanical properties significantly when compared with uncoated scaffolds ( p < 0.05). These results are in accordance with data reported by Bretcanu et al [57] who investigated Bioglass 1 derived scaffolds coated with poly(3-hydroxybutyrate) (P(3HB)). One of the reasons for the improvement of compressive strength could be related to porosity reduction as a result of the coating but this reduction was not significantly important, as mentioned above.…”

“…[15] The enhancement of mechanical properties for the coated scaffolds could be probably better explained as a consequence of the coating itself, e.g., based on the effective interaction of the flexible polymer and the brittle bioactive glass-ceramic scaffold struts during the fracture process, as reported in the literature. [57][58][59][60] The combination of polymers and bioceramics to produce improved scaffolds is inspired by the structure of bone constituted by an inorganic phase (hydroxyapatite), an organic phase (collagen).…”

Effects of biosilicate and bioglass 45S5 on tibial bone consolidation on rats: a biomechanical and a histological study

“…By comparison, porous bioglass promoted bone formation over the entire extension of the defect independent of block size in comparison to control group in goats [21]. An earlier study conducted by Bretcanu et al [22] have revealed that Bioglass Ò /P(3HB) scaffolds have potential as osteoconductive tissue engineering substrates for maintenance and normal functioning of bone tissue. Furthermore, other authors have assumed that the Bioglass 45S5…”

Bone-Biomimetic Biomaterial and Cell Fate Determination

“…For ceramic scaffolds, attempts have been made to reduce brittleness and enhance mechanical performance mainly by reinforcement with coating layers of polymers and/or ceramics. Several biocompatible and biodegradable polymers have been used to coat ceramic scaffolds, including poly(lactic-co-glycolic acid) (PLGA) (Miao et al 2007(Miao et al , 2008, poly(D,L-lactic acid) (PDLLA) Tian et al 2008;Lu et al 2008b;Zhao et al 2009), polycaprolactone (PCL) (Kim et al 2004;Zhao et al 2008;RoohaniEsfahani et al 2011), poly(3-hydroxybutyrate) (PHB) (Bretcanu et al 2009) and silk fibroin (Wu et al 2010;Roohani-Esfahani et al 2012;Li et al 2013b). Some of these polymer coatings have an additional ceramic component in the form of powder or nanoparticles for bioactivity and further strength enhancement (Miao et al 2007;Roohani-Esfahani et al 2011).…”