Fabrication techniques and biomedical applications of strontium-based nanofibers

Strontium (Sr)-based nanofibers have gained great attention in biomedical and tissue engineering applications due to their unique ability to combine nanoscale structural features with the biological activity of Sr ions (Sr²⁺). Nanofibers offer a versatile platform to harness these properties owing to their high surface area, tunable porosity, and mechanical strength. The incorporation of Sr²⁺ ions further enhances their bio-functionality and offers a cost-effective alternative to growth factor-based strategies. Sr²⁺ ions could stimulate the production of growth factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), thereby promoting neovascularization, while also enhancing osteogenesis by mimicking calcium's physiological role, inducing mesenchymal stem cell differentiation, and stimulating extracellular matrix mineralization. This review summarizes recent advances in the fabrication techniques such as electrospinning, assisted-electrospinning, and non-electrospinning, including the design, control composition, morphology, and functionality of Sr-based nanofibers. The mechanisms governing Sr²⁺ ions interactions with cells and tissues are discussed, along with in vitro and in vivo biological outcomes. Our bibliometric analysis shows that Sr-based nanofibers have been most extensively investigated in bone tissue engineering, followed by applications in drug delivery and tumor therapy, with fewer studies exploring skin and cartilage regeneration. This review highlights the advantages and disadvantages of every fabrication strategy, discusses biomedical applications of Sr-based nanofibers, and outlines challenges and future directions for their clinical translation.