Biomedical Applications of Diamond Nanoparticles

Nanomaterials hold tremendous potential in addressing the two major issues faced by our society: providing energy and improving healthcare. Nanodiamond powder produced by detonation and readily available in commercial quantities for moderate price, is one of the most promising carbon nanomaterials for theranostics [1], [2]. Made of ~5 nm diamond particles with large accessible surface and tailorable surface chemistry, it has unique optical, mechanical and thermal properties, and is non-toxic. These properties have recently started to attract a lot of interest among researchers working on different biomedical applications [3]. For tissue engineering scaffolds, the non-toxic fluorescent nanodiamond introduced into biodegradable polymers provides increased strength, visual monitoring, and enhanced biomineralization [4]. In drug delivery, the rational surface modification of nanodiamond allows for enhanced adsorption and chemical binding of the drugs for sustained or triggered drug release. In the area of biomedical imaging and diagnostics, luminescent nanodiamond with NV centers, as well as chemically modified fluorescent nanodiamond, hold tremendous potential to replace toxic semiconductor quantum dots, thus bringing this exciting potential application one step closer to the clinics [5]. The purification, characterization and surface modification of nanodiamond for biomedical applications will be discussed in detail. Recent progress in development of nanodiamond-biodegradable polymer scaffolds for tissue engineering and bone surgery will be reviewed. Surface modifications of nanodiamond for drug delivery exploiting adsorption/desorption mechanisms will be discussed, with illustrations of the use of adsorption/desorption data for rational design of nanodiamond surface for optimal drug delivery platform. Finally, an overview of surface modification of nanodiamond for biomedical imaging will be presented. [1]. V. N. Mochalin, O. Shenderova, D. Ho, Y. Gogotsi The Properties and Applications of Nanodiamonds (Review), Nature Nanotechnology, 7 (1), p.11-23 (2012) [2]. V. N. Mochalin, A. Pentecost, X.-M. Li, I. Neitzel, M. Nelson, C. Wei, T. He, F. Guo, Y. Gogotsi Adsorption of Drugs on Nanodiamond: Toward Development of a Drug Delivery Platform, Molecular Pharmaceutics, 10 (10), p.3728-3735 (2013) [3]. O. Shenderova, D. Gruen, ed. Detonation Nanodiamonds: Science and Applications (2 nd Edition). CRC Press, 2014 [4]. Q. Zhang, V. N. Mochalin, I. Neitzel, K. Hazeli, J. Niu, A. Kontsos, J. G. Zhou, P. I. Lelkes, Y. Gogotsi Multifunctional Nanodiamond-PLLA Scaffolds for Bone Tissue Engineering: Enhanced Mechanical Strength and Biomineralization, Biomaterials, 33 (20), p.5067-5075 (2012) [5]. G. Balasubramanian, A. Lazariev, S. R. Arumugam, et al. "Nitrogen-Vacancy color center in diamond-emerging nanoscale applications in bioimaging and biosensing." Current Opinion in Chemical Biology 20 (2014): 69-77