LAUSR

Non-nano scaled hydroxyapatite (HAP) particles cannot enter the cells, but they are also wildly used in tissue engineering for their excellent bone regeneration. We synthesized a defect-related luminescent micro-scale hydroxyapatite particles (S3) and investigated the effect of S3 during bone regeneration. S3 promoted the formation of mineralized nodules and collagen synthesis of osteoblasts (OBs). Micro-scaled S3 couldn't enter into OBs and couldn't change the Ca2+ concentration of the medium. During the cell differentiation, the location of S3 was tracked by its defect-related luminescence in vitro. Extracellular S3 particles become the nucleation events which promote bone regeneration. The results suggest that micro-scale HAP promoted bone regeneration through extracellular pathways. This result also can explain the reason why hydroxyapatite covered tissue scaffold is more suitable for bone reconstructing.