Preparation, Characterization And Application Of Multifunctional Nanocomposite Particles

There have been growing research interests in the design and fabrication of nanocomposites particles (NCPs) with magnetic and luminescence properties, since this kind of NCPs provides the possibility for enhanced functionality and multifunctional properties in contrast to their more-limited single component counterparts. Because of their unique physical and chemical properties, these NCPs have potential applications in protein and DNA separation, detection biomedical labels, controlled drug release, magnetic resonance imaging and hyperthermia treatment of cancer. In this study, we focus on the preparation, characterization and applications of the magnetic/luminescent NCPs, such as NaYF4:Yb, Er/Tm@SiO2@Fe3O4and PMMA/Fe3O4-ZnS hybrid hollow spheres are shown as follows:(1) In the first chapter, we present a facile method for the fabrication core-shell-structured NaYF4:Yb, Er/Tm@SiO2@Fe3O4NCPs. In this approach, when the EDTA capped NaYF4:Yb, Er/Tm nanoparticles were mixed with the oleic acid modified magnetic Fe3O4nanoparticles in isopropyl alcohol, followed by addition of TEOS and ammonium hydroxide, core-shell NaYF4:Yb, Er/Tm@SiO2@Fe3O4NCPs were directly yielded, neither surface modification nor high temperature was needed. TEM、HRTEM、XRD and DLS were used to characterize the morphology and structure of these NCPs. The magnetic and luminescent properties were characterized by the PL and VSM. The obtained NCPs have very good superparamagnetic and luminescent properties. Preliminary investigation of incubating with HeLa cells displays that the NCPs are easily swallowed and can be used in bioimaging.(2) Magnetic-luminescent organic-inorganic PMMA/Fe3O4-ZnS hybrid hollow spheres have been successfully fabricated via a facile method. When the PMMA templates are covered compactly by inorganic nanoparticles, there will be formed a capillary force which can drive the non-cross linked PMMA chains diffusion from the core particles into the voids between the inorganic nanoparticles, forming a hybrid hollow spheres directly. The morphologies and properties of these spheres were characterized by TEM, SEM, XRD, TGA, VSM, PL and BET. The obtained PMMA/Fe3O4-ZnS hybrid hollow spheres show magnetic and luminescent properties. The loading and in vitro release behavior of the drug on the hollow spheres was investigated with DOX.