Preparation and Characterization of Bioactive Glass-Manganese Dioxide Composite Scaffolds

Inflammation in bone defect after being implanted scaffold is related to oxidative stress, which is caused mainly by higher concentration of hydrogen peroxide (H2O2). Manganese dioxide (MnO2) can catalyze H2O2 decomposition to decrease excessive H2O2 in the surrounding environment of scaffolds. Furthermore, the oxygen (O-2) generated by the decomposition of H2O2 can alleviate the hypoxia caused by insufficient blood supply in bone defects, which is conducive to bone tissue regeneration. Here, a simple redox method was proposed to deposit MnO2 particles on the surface of 3D printed bioactive glass (BG) scaffolds for the preparation of BG-MnO2 composite scaffolds (BGM), which endows BG-MnO2 scaffolds with the ability of H2O2 scavenging and O-2 supplying simultaneously. The results showed that the MnO2 content deposited on the surface of BGM scaffolds was increased with the increase of potassium permanganate concentration in the reaction solution, and the compressive strength of BGM scaffolds was increased with the increase of MnO2 content. However, porosity and degradation rate of these scaffolds with or without MnO2 remained the same. More importantly, BGM scaffolds can continuously catalyze the decomposition of H2O2 to produce O-2 in H2O2 environment. When BGM with different Mn content scaffolds (BMG5 and BGM9) catalyzed the decomposition of H2O2 to produce O-2 in 2 mmol/L H2O2 solution, the saturated oxygen concentration in the solution could reach 8.4 and 11 mg/L, respectively. In vitro cell experiments showed that BGM scaffolds could promote the proliferation and alkaline phosphatase activity of rabbit bone marrow mesenchymal stem cells. Hence, BGM scaffolds show great potential in bone regeneration.

Automated summary

This study investigated a novel BG-MnO2 composite scaffold, finding that it has the ability to scavenge H2O2 and supply O-2 simultaneously, showing great potential for bone tissue regeneration.