Novel antimicrobial phosphate-free glass–ceramic scaffolds for bone tissue regeneration

Abstract

In this study a phosphate-free glass-ceramic porous scaffold was synthesized by a three-step methodology involving slurry preparation, induction of porosity by surfactant-assisted foaming following by freeze-drying and sintering. This inorganic scaffold was characterized by X-ray diffraction, scanning electron microscope (SEM), degradation and bioactivity. Thermal treatment at 750 °C showed two new crystalline phases, combeite and nepheline, into the glassy matrix responsible for its properties. The cell response of the scaffold was also evaluated for using as a bone graft substitute. A commercial Biphasic Calcium Phosphate, BCP, scaffold was assessed in parallel as reference material. Microstructures obtained by SEM showed the presence of macro, meso and microporosity. The glass-ceramic scaffold possesses an interconnected porosity around 31% with a crack-pore system that promote the protein adsorption and cell attachment. Glass-ceramic scaffold with high concentration of calcium ions shows an antimicrobial behavior against Escherichia coli after 24 h of contact. nepheline phase present in the glass-ceramic structure is responsible for its high mechanical properties being around 87 MPa. Glass-ceramic scaffold promotes greater protein adsorption and therefore the attachment, spreading and osteodifferentiation of Adipose Derived Stem Cells than BCP scaffold. A higher calcification was induced by glass-ceramic scaffold compared to reference BCP material.

Laponite/amoxicillin-functionalized PLA nanofibrous as osteoinductive and antibacterial scaffolds

“…Improving tissue restoration and preventing bacterial infection are favorable properties for bone biomaterials 2 , 3 . The prior study showed that LAP-functionalized PLA nanofibers could significantly enhance the proliferation and osteodifferentiation of hBMSCs without any external osteoinductive factors 7 .…”

“…Infection control is one of the leading clinical issues related to regeneration surgery in bone tissue engineering 1 . An ideal bone scaffold will presumably be multifunctional, combining different functionalities to simultaneously promote bone regeneration while also limiting microbial infection 2 , 3 . Replacing traditional manners such as systemic antibiotic administration with the incorporation of antibiotics in scaffolds can be an effective treatment for bone infections 2 , 3 .…”

“…An ideal bone scaffold will presumably be multifunctional, combining different functionalities to simultaneously promote bone regeneration while also limiting microbial infection 2 , 3 . Replacing traditional manners such as systemic antibiotic administration with the incorporation of antibiotics in scaffolds can be an effective treatment for bone infections 2 , 3 . Amoxicillin (AMX) is a semisynthetic, broad-spectrum antibiotic that quickly penetrates cell membranes and inhibits bacterial attachment to periodontal ligament cells 4 .…”

Kinetic study of the transformation of sodalite to nepheline

“…Nepheline can also be found as a crystalline phase developed by heat treatment during the manufacturing process of different materials. For instance, in recent years, glass–ceramic materials containing nepheline have been documented as efficient UltraViolet Light Emitting Diode (UV‐LED) color converters, 4 scaffolds for bone tissue regeneration 5 or for dental applications 6 . Nepheline is also reported in geopolymers, 7 self‐compacting repair mortars, 8 low thermally conductive ceramic foams, 9 or traditional ceramics 10 .…”

Phosphorous pentoxide-free bioactive glass exhibits dose-dependent angiogenic and osteogenic capacities which are retained in glass polymeric composite scaffolds

“…P 2 O 5 -free BGs, that is, from the groups SiO 2 -CaO and SiO 2 -CaO-Na 2 O have shown to be highly advantageous. [6][7][8] These BGs have been shown to be bioactive 6,9,10 and capable of inducing extracellular matrix (ECM) secretion and mineralization by primary human osteoblasts (OBs). 7 In addition, P 2 O 5 -free BG may be particularly useful to some fabrication techniques.…”