Hydroxyapatite Nanowire@Magnesium Silicate Core–Shell Hierarchical Nanocomposite: Synthesis and Application in Bone Regeneration

Abstract

Multifunctional biomaterials that simultaneously combine high biocompatibility, biodegradability, and bioactivity are promising for applications in various biomedical fields such as bone defect repair and drug delivery. Herein, the synthesis of hydroxyapatite nanowire@magnesium silicate nanosheets (HANW@MS) core-shell porous hierarchical nanocomposites (nanobrushes) is reported. The morphology of the magnesium silicate (MS) shell can be controlled by simply varying the solvothermal temperature and the amount of Mg ions. Compared with hydroxyapatite nanowires (HANWs), the HANW@MS core-shell porous hierarchical nanobrushes exhibit remarkably increased specific surface area and pore volume, endowing the HANW@MS core-shell porous hierarchical nanobrushes with high-performance drug loading and sustained release. Moreover, the porous scaffold of HANW@MS/chitosan (HANW@MS/CS) is prepared by incorporating the HANW@MS core-shell porous hierarchical nanobrushes into the chitosan (CS) matrix. The HANW@MS/CS porous scaffold not only promotes the attachment and growth of rat bone marrow derived mesenchymal stem cells (rBMSCs), but also induces the expression of osteogenic differentiation related genes and the vascular endothelial growth factor (VEGF) gene of rBMSCs. Furthermore, the HANW@MS/CS porous scaffold can obviously stimulate in vivo bone regeneration, owing to its high bioactive performance on the osteogenic differentiation of rBMSCs and in vivo angiogenesis. Since Ca, Mg, Si, and P elements are essential in human bone tissue, HANW@MS core-shell porous hierarchical nanobrushes with multifunctional properties are expected to be promising for various biomedical applications such as bone defect repair and drug delivery.

Hydroxyapatite nanowire/collagen elastic porous nanocomposite and its enhanced performance in bone defect repair

“…More interestingly, the natural bone is hierarchically constructed by HAP nanocrystals and collagen matrix at the macro-, micro-, and nanoscales, which endows the natural bone with excellent mechanical properties. 3,9,15 Thus, it is a rational strategy to develop bone gra substitutes based on biomimetics.…”

“…For instance, the scaffolds with rigid matrices could signicantly stimulate the expression of osteogenesis-related genes of mesenchymal stem cells via the mechanical signaling pathways. 9,45,46 In addition, the implanted scaffolds provide sufficient mechanical strength and mechanical stability in vivo to withstand mechanical loading and support the new formed bone. 7,47 In this work, the compressive mechanical properties of the collagen sample and biomimetic UHANWs/Col porous nanocomposite were investigated under dry and rehydrated states, as shown in Fig.…”

Porous Nanocomposite Comprising Ultralong Hydroxyapatite Nanowires Decorated with Zinc‐Containing Nanoparticles and Chitosan: Synthesis and Application in Bone Defect Repair

“…[1][2][3][4][5] Due to the excellent osteogenicity,osteoinductivity,a nd immunological compatibility,a utografts currently remain the clinical gold standard for the repair of large bone defects. [1][2][3][4][5] Due to the excellent osteogenicity,osteoinductivity,a nd immunological compatibility,a utografts currently remain the clinical gold standard for the repair of large bone defects.…”

“…Importantly,t hese composite porouss caffolds can combinet he advantages of organic polymers and inorganic materials, which endows the scaffolds with great potential in bone-tissue engineering. [4,16,25] Because of its good biocompatibility,b iodegradability,a nd nonantigenicity,c hitosanh as been considered as an excellent biomaterialf or various biomedical applications such as drug delivery and tissuee ngineering. [18,19] Various types of HAP-based composite scaffolds, including HAP/collagen, [20,21] HAP/silk fibroin, [22] HAP/chitosan, [15] HAP/gelatin, [23] and HAP/polycaprolactone, [24] werer eported for bone regeneration.…”

“…Millions of people worldwide need treatments to repair damaged bone causedb yt rauma, tumor surgery,i nfection, and aging each year. [1][2][3][4][5] Due to the excellent osteogenicity,osteoinductivity,a nd immunological compatibility,a utografts currently remain the clinical gold standard for the repair of large bone defects. [6,7] However,asecond surgical site is alwaysr equired for the harvest of the autograft, leadingt oa ssociated prob-lems, such as limited supply,d onor-site morbidity,a nd risk of infection.…”