Title: Rare-earth doped apatite nanocrystals for cell and implanted biomaterial tracking 

Advisor:
Haifeng Chen, PhD, Department of Biomedical Engineering, Peking University
Younan Xia, PhD, Department of Biomedical Engineering, Georgia Institute of Technology & Emory University
Committee Members:
Yingfang Ao, PhD, Institute of Sports Medicine, Peking University Third Hospital
Ying Luo, PhD, Department of Biomedical Engineering, Peking University
Xiaojie Duan, PhD, Department of Biomedical Engineering, Peking University

Abstract: 

Nano-sized apatite crystals are good candidates for repair or reconstruction of human bones and teeth, and main component of bone tissue engineering scaffolds, due to their excellent biocompatibility and osteogenicity. Apatite has a stable crystal structure, which could be employed as a host matrix for lanthanides doping to prepare both downconversion and upconversion fluorescent nanoparticles. In design of the thesis, the lanthanide doped apatite nanocrystals will be prepared by hydrothermal synthesis, and their structure, luminescence properties, cell proliferation, and fluorescent tracking will be investigated. The new fluorescent nano-apatite can not only form bonding with bone tissue, but also provide stable and clear fluorescence imaging. The novel fluorescence probe is expected to overcome the shortcomings such as instability and photobleaching of organic fluorophores, and the potential toxicity from quantum dots. They can be utilized for long-term bioimaging, distinguishing scaffold from newly formed bone tissue or identifying the interface between implanted material and bone tissue on the histological sections, and tracking the distribution of degraded scaffold fragments in vivo.