Bioactive Glasses Enriched with Strontium or Zinc with Different Degrees of Structural Order as Components of Chitosan-Based Composite Scaffolds for Bone Tissue Engineering

Abstract

The development of innovative biomaterials with improved integration with bone tissue and stimulating regeneration processes is necessary. Here, we evaluate the usefulness of bioactive glasses from the SiO2-P2O5-CaO system enriched with 2 wt.% SrO or ZnO in the manufacturing of chitosan-based scaffolds. Bioglasses produced using the sol-gel method were subjected to thermal treatment in different regimes. Chitosan/bioglass composites were produced with a weight ratio. Bioglasses were evaluated via TG-DTA, FTIR, and SEM-EDS before and after incubation in simulated body fluid (SBF). The release of ions was tested. The cytocompatibility of the composites in contact with MG63 osteoblast-like cells was evaluated. The results showed that the presence of the crystalline phase decreased from 41.2–44.8% for nonmodified bioglasses to 24.2–24.3% for those modified with ZnO and 22.0–24.2% for those modified with SrO. The samples released Ca2+, Zn2+, and/or Sr2+ ions and were bioactive according to the SBF test. The highest cytocompatibility was observed for the composites containing nonmodified bioglasses, followed by those enriched with SrO bioglasses. The least cytocompatible were the composites containing ZnO bioglasses that released the highest amount of Zn2+ ions (0.58 ± 0.07 mL/g); however, those that released 0.38 ± 0.04 mL/g were characterised by acceptable cytocompatibility. The study confirmed that it is feasible to control the biological performance of chitosan/bioglass composites by adjusting the composition and heat treatment parameters of bioglasses.

Chitosan and Sodium Hyaluronate Hydrogels Supplemented with Bioglass for Bone Tissue Engineering

“…The designed value, dv (0.5), means that the size in 50% v/v of particles in the sample population is smaller than the value dv. The phase compositions of bioglass post thermal treatment are presented in our previous publication [43]. In bioglass annealed at 650 • C/10 h, a significantly higher crystalline phase content was observed compared to bioglass annealed at 550 • C/3 h. In brief, for P5, bioglass crystallinity increased from 41.2 to 44.8 wt.%; for P5Sr2, it increased from 22.0 to 24.4 wt.%; but for P5Zn2, it practically did not change (24.2 and 24.3 wt.%) [42].…”

“…The following crystalline phases were identified in the reference and SrO-doped bioglass: pseudowollastonite, wollastonite, and quartz. In contrast, hydrastonite and crystobalite were further identified in ZnO-doped bioglass [43]. Finally, the bioglass samples were used as components of the chitosan/sodium hyaluronate/bioglass composites (Table 2).…”

“…Strontium ions exhibit osteoinductive effects by improving osteoblast proliferation and have antibacterial properties [42]. Furthermore, when selecting the appropriate thermal treatment parameters for bioglass, the degree of its structure and phase composition can be altered, which, as a result, affects the biocompatibility of the composite [43]. Peptide nanoparticles can also be incorporated into the composition of polysaccharide/bioglass composites [44,45], so that the beneficial effects of individual components can be maximised synergistically.…”