Magnetic Nanoshell

M. N. Hansen, L. S. Chang and A. Wei, Resorcinarene-encapsulated gold nanorods Solvatochromatism and magnetic nanoshell formation, Supramolecular Chemistry, 20(1), 35-40 (2008). 

Hirsch, L.R., Stafford, R.J., Bankson, J.A., Sershen, S.R., Rivera, B., Price, R.E., Hazle, J.D., Halas, N.J. and West, J.L (2003) Nanoshell-mediated near-infrared thermal therapy of tumors under magnetic resonance guidance. Proceedings of the National Academy of Sciences of the United States of America, 100, 13549-13554. 

Hirsch LR, Stafford RJ, et al. Nanoshell-mediated near-infrared thermal therapy of tumors under magnetic guidance. Proc Natl Acad Sci USA 2003 100 13549-13554. 

The presented results evidenced that the hexaferrite SrFei20i9 used for fabrication of magnetic materials with advanced functional features has intricate chemical composition and irregular micro-structure with nanoshells enriched by dopants. The dopants and binding agents play the important part in the formation of the required granular structure. 

As a result, a vast number of nano-carriers have been used for the tumour-targeted delivery of active principles they include liposomes," " micelles," " polymeric nanoparticles," " " solid lipid nanoparticles (SLN)," dendrimers, nanoshells, and magnetic nanoparticles. " Examples of nano-carriers with proven clinical efficacy are reported in Table 12.2. 

Studies have also been conducted supporting the use of nanoshell-mediated cancer therapy in vivo. In the first mouse model evaluated, nanoshells were directly injected into transmissible venereal tumors in mice. Temperature increase at different tissue depths was recorded by magnetic resonance thermal imaging (MRTI) (Fig. 15.12). The mean temperature increase for nanoshell-treated tumors was almost 40°C, with maximum temperatures above the threshold necessary to induce irreversible damage. By comparison, mean increase for controls without nanoshells was less than 10°C. Histology of excised tumors confirmed that tissue damage was confined to areas of nanoshell localization. This marked the first time local heat delivered by nanoshell therapy was shown to successfully damage tumor tissue in vivo. 

Nanoparticles (<100 nm, inorganic or organic) for implanted materials, nanoshells, and nanoemulsions for drug delivery quantum dots (<8 nm) and magnetic nanoparticles for labeling in diagnostics and implanted sensors and medical devices... 

Nanoshell magnetic resonance imaging contrast agents. Journal of the American Chemical Society, 129, 2139-46. 

S. K. and Cho, M. (2006) Designed fabrication of multifunctional magnetic gold nanoshells and their application to magnetic resonance imaging and photothermal therapy. Angewandte Chemie-International Edition, 45,... 

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