Nowadays, based on nanotechnology, bio-inspired self-assembled nanomaterials emerged as a type of charming biomaterials for bone and cartilage repair. For example, rosette nanotubes (RNTs) are novel biomimetic self-assembled supramolecular structures, whose basic building blocks are guanine (G) and cytosine (C) DNA base-pairs. Their units undergo a hierarchical process to form a six-membered supermacrocycle by hydrogen bonds in physiological conditions, and then the rosettes form a stable stack with an inner channel 11Å in diameter. They can dissolve in physiological environments and solidify into a viscous gel at body temperatures binding to severed tissue. Moreover, RNTs are similar in size to natural collagen in bone and cartilage and previous studies have found that they can enhance cell adhesive protein adsorption and improve cell attachment and long-term functions. In addition, RNTs are able to be incorporated with a variety of drugs or growth factors for improving tissue regeneration. In this thesis, the ability of RNTs to improve bone and cartilage repair was in vitro tested from three aspects: material properties, drug/growth factor delivery and biological functions. More importantly, in vivo studies showed that RNT composites were injected and solidified in the bone defects created in the tibia and femur of pigs. Especially, such composites enhanced bone healing compared to negative (empty) and positive (autograft) controls. Thus, the present thesis provides a novel biomaterial (RNTs) that can be in situ injected to improve bone and cartilage repair.
"Self-assembled Rosette Nanotubes for Drug Delivery and Bone/Cartilage Tissue Regeneration"
Chemistry Theses and Dissertations.
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