One-Step Gas Foaming Strategy for Constructing Strontium Nanoparticle Decorated 3D Scaffolds: a New Platform for
Yujie Chen1,2,3, Yucai Li1,2,3, Xinyi Wang4
1Laboratory of Key Technology and Materials in Minimally Invasive Spine Surgery, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200336, China.
Abstract:
The management of critical-sized bone defects poses significant clinical challenges, particularly in the battlefield and trauma-related injuries. However, bone tissue engineering scaffolds that satisfy high porosity and good angiogenic and osteogenic functions are scarce. In this study, 3D nanofiber scaffolds decorated with strontium nanoparticles (3DS-Sr) were fabricated by combining electrospinning and gas foaming. Sodium borohydride (NaBH4) served a dual role as both a reducing and gas-foaming agent, enabling a one-step process for expansion and modification. In vitro experimental results demonstrated that 3DS-Sr possessed an integrated multilayered porous structure. It promoted angiogenesis by upregulating the expression of hypoxia-inducible factor-1α (HIF-1α) protein and phosphorylation of ERK through the sustained release of Sr2+ and created a favorable microenvironment for osteogenesis by activating the Wnt/β-catenin pathway. In vivo experiments indicated that 3DS-Sr promoted cranial bone regeneration by synergistically promoting the effects of vascularization and osteogenesis. In summary, this study proposed a bioactive bone scaffold in a "one stone, two birds" manner, providing a promising strategy for bone defect repair.
