Multispectral MRI Contrast Through Cylindrical Nanoshell Agents

Gary Zabow^1,2, Stephen Dodd¹, John Moreland², Alan Koretsky¹

Thanks to the processing control afforded by top-down microfabrication techniques, geometrically tailored magnetic microparticles have recently been shown able to produce tunable, multispectral MRI contrast. Here we demonstrate a new form of such agent based on new cylindrical nanoshell structure designs. These hollow magnetic cylinders can produce large NMR frequency shifts through the control of the cylinder materials, aspect ratios and wall thicknesses. Apart from yielding distinct frequency shifted NMR peaks, it is also shown that these cylindrical nanoshell structures exhibit good mechanical robustness and automatically self-align (as is required) to the applied MRI B₀ field.