Incomplete osseointegration is primary cause of failure for orthopedic implants. New biomaterials that present stable signals promoting osteogenesis could reduce failure rates of orthopedic implants. In this study bone morphogenetic protein‐2 (BMP‐2) was delivered from titania nanotubes (Nt) modified with chitosan/heparin polyelectrolyte multilayers (PEMs). The surfaces were characterized by scanning electron microscopy and X‐ray photoelectron spectroscopy. BMP‐2 release from the surfaces was measured in vitro for up to 28 days. After an initial burst release of BMP‐2 during the first 2 days, most of the BMP‐2 remained on the surface. To determine the osteogenic properties of these surfaces, they were seeded with rat bone marrow cells; alkaline phosphatase (ALP) activity, total protein, calcium deposition, and osteocalcin were measured up to 4 weeks in vitro. When compared to Nt surfaces, the surfaces with BMP‐2 induce greater osteocalcin and calcium deposition. PEMs provide sustained presentation of BMP‐2, from a biomimetic surface. This enhances the osteogenic properties of the surface without requiring supraphysiologic growth factor dose. This growth factor delivery strategy could be used to improve bone healing outcomes and reduce complications for recipients of orthopedic implants.

中文翻译：

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从聚电解质多层传递骨形态发生蛋白-2增强纳米结构二氧化钛的成骨活性

骨整合不完全是骨科植入物失败的主要原因。呈现稳定信号促进成骨的新生物材料可以降低骨科植入物的失败率。在这项研究中，骨形态发生蛋白-2 (BMP-2) 是从用壳聚糖/肝素聚电解质多层 (PEM) 改性的二氧化钛纳米管 (Nt) 传递的。通过扫描电子显微镜和 X 射线光电子能谱对表面进行表征。在体外测量 BMP-2 从表面的释放长达 28 天。在最初的 2 天 BMP-2 首次爆发释放后，大部分 BMP-2 保留在表面上。为了确定这些表面的成骨特性，它们被接种了大鼠骨髓细胞；碱性磷酸酶 (ALP) 活性、总蛋白、钙沉积、和骨钙素在体外测量长达 4 周。与 Nt 表面相比，具有 BMP-2 的表面诱导更多的骨钙素和钙沉积。PEM 从仿生表面提供 BMP-2 的持续呈现。这增强了表面的成骨特性，而不需要超生理生长因子剂量。这种生长因子递送策略可用于改善骨愈合结果并减少骨科植入物接受者的并发症。