Abstract:
This dissertation addresses the creation of a multifunctional nanoplatform for cancer targeting, imaging, and therapy. Magnetic oxide nanoparticles were labeled with silane coupling agents that could be used for targeting. The magnetic oxides have application as contrast enhancing agents for magnetic resonance imaging. Copper-nickel binary alloy nanoparticles were prepared for possible use in Curie temperature limited hyperthermia therapy. Spherical, single crystal iron oxide nanoparticles with average diameters of 4 nm, 6 nm, 8 nm, 11 nm, or 16 nm were prepared using published procedures. The iron oxide particle chemistry was extended to synthesize 13 nm diameter CoFe_2 O_4 , 9 nm diameter MnFe_2 O_ 4 , and 12 nm diameter NiFe_2 O_4 . The particles had a coating of oleic acid and oleylamine ligands. Silane coupling chemistry was used to displace these ligands with either β-aminoethyl-ϒ-aminopropyl-trimethoxysilane, triethoxysilane-PEG, or triethoxysilane-biotin. The silane ligands would allow the particles to be conjugated with a targeting group. New chemistry was developed to synthesize fcc CuNi nanoparticles with the objective of finding methods that give particles with an average size less than 50 nm, a narrow distribution of particle sizes, and control of particle composition. The particle synthesis involves the reduction of a mixture of copper(II) and nickel(II) and the reduction conditions included diol reduction, polyol synthesis, seeding by diol reduction, and oleate reduction. One of the main issues is the formation of hcp nickel particles as a containment in the method. The factors that avoided the formation of hcp nickel particles and allow only fcc particles to form were the choice of reducing agent, ratio of surfactants, and heating time. Both the oleate reduction and diol reduction gave a mixture of the hcp and fcc phases. By controlling certain reaction conditions, such as keeping the ratio of oleic acid to oleylamine 1:1 and slowly heating to reflux for 30 minutes, only fcc nanoparticles were formed. The method of making CuNi nanoparticles by diol reduction gave the best result and it consisted of a total amount of 1 mmol of Cu(acac)_2 and Ni(acac)_2 , 5 mmol of 1,2 hexadecanediol, 1.5 mL of oleic acid, 1.5 mL of oleylamine and 15 mL of benzyl ether. It made fcc CuNi, provided control of composition, and gave particles with average size smaller than 100 nm.
