Synthesis Of Inorganic Nanomaterials For Tumor Diagnosis And Treatment

Since cancer has posed serious threat to human health, it is of great importance to provide approaches for early diagnosis and effective therapies. In last two decades, due to the remarkable progress of nanotechnology, nanomaterials with the intrinsic properties have been extensively investigated for diagnostic and therapeutic purposes, especially in oncology. Multifunctional theranostic nanomaterial-platform for simultaneous diagnosis and therapy is currently a promising stratagy to enhance therapeutic efficiency and reduce side effects. However, much more effort is still needed on the designing and fabricating theranostic nanomaterials suitable for clinic translation.In this dissertation, three kinds of nanomaterials are developed for tumor imaging and photothermal therapy. These investigations consist of:Chapter1. A general introduction to tumor diagnosis and therapy methods is presented. We also describe the applications of nanomaterials in oncology and highlight the new trend of theranostic nanomaterials. Finally, basis and main contents of this dissertation are listed.Chapter2. Au cubic nano-aggregates with particular morphology and size were prepared and explored for photoacoustic imaging (PAI) and photothermal therapy (PTT). We demonstrate a simple and cost-effective method to synthesize a novel Au cubic nano-aggregates structure with edge-length of80nm (Au-80CNAs) using templates. The Au-80CNAs display strong near-infrared (NIR) absorption, excellent water-solubility, high photothermal conversion efficiency, good photo-stability, and good biocompatibility. The in vitro and in vivo studies demonstrate that Au-80CNAs act as both PTT and PAI contrast agents, indicating that Au-80CNAs show great potentials for theranostic applications.Chapter3. Fe3O4-Au nanocomposites were prepared and explored for magnetic resonance imaging (MRI) and PTT. Fe3O4-Au nanocomposites display NIR absorption and the availability of photothermal conversion, enabling effective killing of cancer cells under the NIR irradiation. Moreover, Fe3O4-Au nanocomposites exhibit T2contrast enhancement effect. These results indicate that nanocomposites are promising theranostic platforms combining MRI and PTT.Chapter4.9-nm-sized FePt-iron oxide core-shell nanoparticles (FePt@Fe2O3) were synthesized through thermo decomposition process. The nanoparticles with appropriate surface modifications disperse well in water and are biocompatible. FePt@Fe2O3nanoparticles exhibit strong NIR optical absorption and thus generate heat under NIR irradiation. In vitro study shows that FePt@Fe2O3can efficiently kill cancer cells after exposed to808nm NIR laser for5min, demonstrating the potentials of FePt@Fe2O3for PTT.