Porous functionally graded scaffolds of poly (ε-caprolactone)/ZnO nanocomposite for skin tissue engineering: Morphological, mechanical and biological evaluation

The gradient or hierarchical porosity in various natural tissues is a crucial factor for cell migration and mechanical stabilization. In the present study, poly (epsilon-caprolactone)/zinc oxide (PCL/ZnO) nanocomposite scaffolds containing 0, 5, 10, and 15 wt.% of ZnO nanoparticles were synthesized using salt leaching and solvent casting method to achieve a porous functionally graded structure. X-ray diffractometer (XRD), Fourier transforms infrared spectrometer (FTIR), and scanning electron microscopy (SEM) were respectively used to investigate the phase structure, functional groups, and morphology of the synthesized scaffolds. Additionally, their mechanical properties, biodegradation behavior, cytotoxicity, and cell attachment were assayed via compressive test, immersing in phosphate buffer solution (PBS) for up to 28 days, MTT assay, and SEM, respectively. The obtained results showed that all prepared scaffolds reached a three-layered porous functionally graded structure. While, PCL/ZnO scaffold with 5 wt.% ZnO nanoparticles had the most integrated structure and the highest compressive strength, measured 145.66 +/- 7.28 MPa. Furthermore, the most weight loss as a biodegradation parameter was obtained less than 2%. In addition, all prepared samples exhibited excellent cell adhesion without cytotoxicity.

Automated summary

The gradient or hierarchical porosity in various natural tissues is important for cell migration and mechanical stabilization. In this study, poly (epsilon-caprolactone)/zinc oxide (PCL/ZnO) nanocomposite scaffolds with different percentages of ZnO nanoparticles were synthesized to achieve a porous functionally graded structure. The results showed that the scaffold with 5 wt.% ZnO nanoparticles had the most complete structure and highest compressive strength, as well as good biodegradation behavior and cell adhesion.