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arXiv · 2103.09559

Fabrication of a nanoparticle-containing 3D porous bone scaffold with proangiogenic and antibacterial properties

Abstract

3D porous scaffolds based on agarose and nanocrystalline apatite, two structural components that act as a temporary mineralized extracellular matrix, were prepared by the GELPOR3D method. This shaping technology allows the introduction of thermally-labile molecules within the scaffolds during the fabrication procedure. An angiogenic protein, Vascular Endothelial Growth Factor, and an antibiotic, cephalexin, loaded in mesoporous silica nanoparticles, were included to design multifunctional scaffolds for bone reconstruction. The dual release of both molecules showed a pro-angiogenic behaviour in chicken embryos grown ex ovo, while, at the same time providing an antibiotic local concentration capable of inhibiting Staphylococcus aureus bacterial growth. In this sense, different release patterns, monitored by UV-spectroscopy, could be tailored as a function of the cephalexin loading strategy. The scaffold surface was characterized by a high hydrophilicity, as determined by contact angle measurements, that facilitated the adhesion and proliferation of preosteoblastic cells.

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Juan L. Paris, Nuria Lafuente-Gomez, M. Victoria Cabanas, Jesus Roman, Juan Pena, Maria Vallet-Regi. 2021-03-17. Fabrication of a nanoparticle-containing 3D porous bone scaffold with proangiogenic and antibacterial properties. https://doi.org/10.1016/j.actbio.2019.01.013

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