Carbon dots: Promising biomaterials for bone-specific imaging and drug delivery

Zhili Peng, Dali University
Esmail H. Miyanji, University of Miami
Yiqun Zhou, University of Miami
Joel Pardo, University of Miami
Sajini D. Hettiarachchi, University of Miami
Shanghao Li, University of Miami
Patricia L. Blackwelder, University of Miami
Isaac Skromne, University of Miami
Roger M. Leblanc, University of Miami

Abstract

Bone-related diseases and dysfunctions are heavy burdens on our increasingly aged society. One important strategy to relieve this problem is through early detection and treatment of bone-related diseases. Towards this goal, there has been constant interest in developing novel bone-specific materials for imaging and drug delivery. Currently, however, materials that have high affinity and specificity towards bone are very limited. Carbon dots (C-dots) synthesized from carbon nanopowder bind to calcified bones in vivo with high affinity and specificity. In this study we show that bone binding is highly unique to a specific type of C-dot, and that this binding is non-toxic. Significantly, C-dots derived from other raw materials did not show any bone binding properties. These differences are attributed to the differences in surface chemistry of C-dot preparations, highlighting the heterogeneous nature of C-dots. Importantly, bone-binding by carbon nanopowder derived C-dots is not significantly altered by chemical functionalization of their surface. These unique properties indicate the potential applications of carbon nanopowder-derived C-dots as highly bone-specific bioimaging agents and drug carriers.