Development of bioactive SF/HAp/ZnO scaffolds incorporating succinic acid with potential bone regeneration capabilities

Abstract

The challenges associated with using autografts for repairing bone defects have increased the demand for synthetic bone graft substitutes that can offer both structural support and biological activity. In this research, we developed a composite scaffold made of silk fibroin, hydroxyapatite, and ZnO (SF/HAp/ZnO), incorporating succinic acid (SA) as a functional additive to improve the physicochemical and biological properties of the scaffold. The morphology of the synthesized scaffold was confirmed by FESEM analysis, and a rougher morphology than pure SF was observed in the scaffolds. The study revealed that the scaffold displayed slow degradation (4.84% after 21 days in S4) and high swelling in vitro, and was hydrophilic in nature. A significant difference was observed in the specific strength of the scaffold. Importantly, SA acted as a modulator of surface chemistry, creating a favorable interface for cell attachment and proliferation. In vitro biocompatibility studies using calcein, DAPI, and PI staining (live/dead assay) confirmed that the SA-functionalized scaffold was non-toxic and supported high viability of MC3T3-E1 pre-osteoblasts after 48 hours. The findings indicated that the use of succinic acid delayed the degradation time. This multifunctional composite scaffold showed great potential for use in bone tissue engineering.