Marine plankton exoskeleton-derived honeycombed hydroxyapatite bone granule for bone tissue engineering

The recovery of biocompatible implantable biomaterials from biowaste is a significant method for protecting both human health and the environment concerns. This study aimed to evaluate the possibility of using hydroxyapatite (HAp) granules derived from planktonic exoskeleton bone in the ocean (OceanBone-HAp) as a bone graft substitute. The morphology and physiochemical properties of the OceanBone-HAp were evaluated using SEM, XRD and FT-IR. In addition, the absence of heavy metals and abundance of trace elements in OceanBone-HAp was confirmed using ICP-OES analysis. Moreover, in vitro results showed that OceanBone-HAp improved cell proliferation, adhesion, differentiation, and infiltration, compared to stoichiometric synthetic HAp granules (pure HAp). Additionally, OceanBone-HAp improved the expression of osteogenic related markers, by upregulation of ALP, collagen type-1αI(Col1αI), osteocalcin (OCN), and bone sialoprotein (BSP), which was confirmed using quantitative real-time polymerase chain reaction. Furthermore, in vivo bone regeneration was also evaluated using a rabbit calvarial defect model, and the results showed that the area of mature bone formation was significantly higher for OceanBone-HAp than pure HAp. These results demonstrated that OceanBone-HAp granules have good potential for use in bone healing as a bone graft material.