[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] In the United States alone, approximately 1.6 million people are diagnosed with cancer and over 500,000 people die of cancer each year. According to the American Cancer Society the probability that a male and female will die of cancer are roughly one in four and one in six, respectively. Though current research and development has reduced the mortality rate, the effectiveness of treatment options are severely limited. There has been a rising interest in the literature focused on developing materials with the ability to selectively treat and diagnose a disease or illness. Iron-platinum nanoparticles have great potential as magnetic resonance imaging (MRI) agents. These superparamagnetic materials have been studied as they may offer a better alternative to current materials. Several different mechanisms for their formation have been described, and multiple parameters have been used to control the size and shape of these nanoparticles. Variables such as the amounts of surfactant, heating rates, and concentration of metal precursors were explored. The synthesis produced nanoparticles with a disordered face-centered cubic (fcc) structure, subsequent annealing could be performed to produce the face-centered tetragonal crystal structure. The nanoparticles size and shape were analyzed using transmission electron microscopy (TEM) along with ImageJ software. The results of these syntheses show that the amount of surfactant used during the synthesis has a significant effect on the size and shape of the nanoparticles. The cubic and spheroid shaped nanoparticles were analyzed for variations in unit cell structure, composition, or magnetic properties. The composition of the nanoparticles was analyzed with energy dispersive X-ray spectroscopy (EDS) and inductively coupled plasma mass spectrometry (ICP-MS). Unit cell structure was analyzed using powder X-ray diffraction (XRD). Magnetic measurements were obtained using a 7T MRI instrument. These analyses have shown that the unit cell structure, composition, and magnetic characteristics are different for the cubic and spheroid shaped nanoparticles. The iron-platinum nanoparticles have been coated by a silicon-dioxide network using a silanization reaction developed from the Stober process. Magnetic characteristics and compositional analysis of the coated iron-platinum nanoparticles were performed again using both MRI and ICP-MS. The surface of the silicon-dioxide coated ironplatinum nanoparticles was functionalized using 3-chloropropyltrimethoxy silane. The chlorine functional groups were then replaced with an azide followed by a click reaction to produce beta-cyclodextrin functionalized silica coated iron-platinum nanoparticle. An inclusion study was performed to analyze the beta-cyclodextrin functionalization reactions. These nanoparticles systems have great potential as cancer therapeutic and diagnostic agents.
BROADBAND POLARIZATION CONVERSION BASED ON SMALL-SIZE METAMATERIAL IN THE GHz BAND
