Polyurethane-Calcium Peroxide Composite Nanofibrous Scaffolds with Controlled Oxygen Release for Tissue Engineering Applications

Cell survival of thick engineered scaffolds is often compromised due to limited oxygen diffusion. Therefore, the design of oxygen-delivering nanofibrous polyurethane (PU)-calcium peroxide (CPO) scaffolds was investigated in this study. The average size of CPO nanoparticles was 57.7 +/- 7.33 nm. The average diameter of PU fibers was 0.51 +/- 0.23 pm, which was increased to 0.68 +/- 0.27, 0.98 +/- 0.47, and 1.68 +/- 1.14 pm upon incorporation of 0.1 wt.%, 0.5 wt.% and 1 wt.% CPO, respectively. The CPO-containing scaffolds could produce oxygen for at least 13 days. Samples containing 0.5% CPO showed the highest oxygen release without a significant change in pH. For this sample, the addition of ascorbic acid as an antioxidant to counteract the possible formation of ROS, reduced the fiber diameter to 0.64 +/- 0.50 pm and increased the oxygen release. Adding 0.5% CPO improved the cell viability on the fifth day. In addition, the PU-CPO composite scaffold showed strong antibacterial activity. Overall, designed scaffolds could be useful in different tissue engineering applications to overcome the limited oxygen availability early after implantation.