Boron Nitride Nanotubes Reinforce Tricalcium Phosphate Scaffolds and Promote the Osteogenic Differentiation of Mesenchymal Stem Cells.
Incorporating boron nitride nanotubes (BNNTs) into ceramic matrices is a promising strategy for obtaining multifunctional composites. In this study, the application of BNNTs in reinforcing β-tricalcium phosphate (β-TCP) scaffolds manufactured using laser sintering is demonstrated. BNNTs contribute to the effective inhibition of both grain growth and phase transformation in β-TCP. Moreover, they can strengthen the grain boundaries and boost the fracture mode transition from intergranular to transgranular. BNNTs play an active role in reinforcing β-TCP in terms of load transfer and energy absorption by the synergistic mechanisms of pull-out, peel-off, crack bridging and deflection. With a BNNT content of 4 wt%, the elastic modulus, hardness, compressive strength and fracture toughness of β-TCP increase by 46%, 39%, 109% and 35%, respectively. Umbilical cord mesenchymal stem cells (UC-MSCs) were isolated with high purity, and surface molecule characterization revealed that they were CD90+, CD29+, CD73+, CD31-, CD34- and CD45-. UC-MSCs on BNNTs/β-TCP scaffolds were characterized by more positive Alizarin Red staining as well as up-regulated expression of osteoblast markers, as revealed by quantitative real-time reverse transcriptase polymerase chain reaction analysis and immunofluorescence staining. These results are the first to demonstrate that BNNTs promote the osteogenic differentiation of UC-MSCs, indicating good osteoinductive properties for use in bone scaffolds. This study paves the way for the potential use of a BNNT/β-TCP scaffold in bone repair.
Cijun
C
Shuai
Chengde
C
Gao
Pei
P
Feng
Tao
T
Xiao
Kun
K
Yu
Youwen
Y
Deng
Shuping
S
Peng
D001672:Biocompatible Materials / Q000494:pharmacology; D015415:Biomarkers / Q000378:metabolism; D001896:Boron Compounds / Q000494:pharmacology*; D002130:Calcium Phosphates / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010012:Osteogenesis / Q000187:drug effects*; D013314:Stress, Mechanical; D054457:Tissue Scaffolds / Q000737:chemistry*; D014470:Umbilical Cord / Q000166:cytology
D001672:Biocompatible Materials; D015415:Biomarkers; D001896:Boron Compounds; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; C017282:boron nitride