Bone-biomimetic nanocomposite materials

Bone-biomimetic nanocomposite materials based on peptides potentially aimed at orthopedic applications are rather seldom reported a thermoreversibly gelling block copolymer conjugated to HA-nucleating peptides, however, has been reported similar... 

Gelinsky M, Welzel PB, Simon P, Bernhardt A, Konig U. Porous three-dimensional scaffolds made of mineralised collagen preparation and properties of a biomimetic nanocomposite material for tissue engineering of bone. Chem Eng J 2008 137(l) 84-96. 

Bernhardt et al. [234] obtained a synthetic material that mimics the composition and structure of the extracellular bone matrix, which mainly consists of Coll fibrils, mineralized with HAp (nano)crystals. This nanocomposite material was produced in a biomimetic process, in which Col fibril assembly and mineralization with HAp occur simultaneously. The authors observed that the membranes from biomimetically mineralized Coll show a substantial influence on the osteogenic differentiation of human bone-marrow-derived stromal cells (hBMSCs). The bone-like composition of the material, combined with its stimulating effect on the osteogenic differentiation of hBMSC, makes it appropriate for human bone regeneration. 

In order to improve the mechanical strength and biological performance of chitosan and make it more suitable for bone repair and regeneration, it has been a widely accepted approach to incorporate other biopolymers or inorganic materials into chitosan scaffolds. Furthermore, from the viewpoint of biomimetics, bone is a nanocomposite of minerals and proteins. Therefore, attempts have been made recently to develop nanocomposites for bone tissue engineering, among which... 

It is important to emphasize that many natural tissues are essentially composed of nanoscale biopolymers or biocomposites with hierarchical architectures. Therefore, by mimicking the structure and property of their natural counterparts, synthetic nanopoiymers and nanocomposites are very likely to enhance/regulate the functions of specific cells or tissues. This principle has been demonstrated by the success of bioinspired polymers and composites in both clinical practice and in laboratory research. In particular, bone is the hierarchical tissue that has inspired a myriad of biomimetic materials, devices, and systems for decades. This chapter focuses on this well-developed area of biomimetic or bioinspired nanopoiymers and nanocomposites for bone substitution and regeneration, especially those with high potentials for clinical applications in the near future. 

In another work, an in situ biomimetic synthesis of Gel/HAp nanocomposite powders with varied proportions was described [247]. The use of HAp crystals and Gel, the soluble form of bone protein, makes the nanocomposites comparable to natural bone in constituents. The authors found that the application of biomimetic principles improves crystal morphology and the interaction of HAp crystals with the Gel molecules, as seen through in vitro characterizations. The best results were obtained for 80 20 proportions of HAp to Gel, which proved to be closest to the characteristics of natural bone. The in vivo implantation studies in the femoral condyle of the animals, as assessed by serial post-operative follow-up radiography and histological evaluation, revealed a good biocompatibility and bone-regeneration ability of the material. 

Li, X., Chang, J., 2008. Prqraration of bone-like apatite-collagen nanocomposites by a biomimetic process with phosphorylated coUagen. Journal of Biomedical Materials Research. Part A 85 (2), 293-300. Available at http //www.ncbi.nlm.nih.gov/pubmed/17688292 (accessed 10.10.14.). 

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