Bone tissue engineering electrospun scaffolds based on layered double hydroxides with the ability to release vitamin D3: Fabrication, characterization and in vitro study

Abstract Bone tissue engineered scaffolds can improve and accelerate the tissue regeneration alongside controlled release of drugs and signaling molecules while providing a suitable condition for cell adhesion and, proliferation. The current study involves the fabrication of Poly (ɛ-caprolactone) (PCL) electrospun scaffolds enriched with vitamin D3 (VD3)-loaded layered double hydroxides (LDHs) nanohybrid, in different concentrations. Characterizations confirmed successful synthesis of LDH and formation of crystalline planes and intercalation of VD3 in LDH with 65% encapsulation efficiency. Addition of low concentrations of LDHs nanohybrid to PCL scaffold led to a decrease in the fiber diameter; however, an increase in the surface roughness was observed at higher concentrations. Mechanical properties and porosity of the scaffolds were also evaluated and the results showed a decrease in elongation modulus in nanohybrid enriched scaffolds and no significant differences in porosity percentage was observed. Studies on bioactivity of scaffolds subjected to simulated body fluid (10 X SBF) indicated that the VD3 encouraged the formation of apatite-like crystals in vitro. Furthermore, the degradation rate of scaffolds increased due to the addition of nanohybrid. The cumulative release of VD3 showed the same pattern for all scaffolds through the diffusion as the main controlling mechanism of release. In vitro biological responses of the scaffolds were studied using MG-63 cell lines culture. The results indicated that nanohybrid containing scaffolds could highly support cell adhesion and proliferation. Likewise, alkaline phosphatase activity as an indicator of osteoconductivity for scaffolds showed no significant differences between nanohybrid containing and pure PCL scaffolds (p > .05). The results confirmed the potential of VD3-loaded LDH/PCL electrospun scaffolds for bone tissue engineering.