Preparation And Properties Of Magnetic-Optical-Thermal Multifunctional Hybrid Nanocomposites

Multifunctional hybrid nanocomposites always contain two or several kinds of nanoparticles with different functions, which are constructed through the core-shell structure or hybrid nanostructure. They have many applications in areas such as catalysis,sensing, imaging, drug delivery, gene regulation, anti-cancer therapy and so on. Lanthanide ions doped Gd³⁺-containing fluoride nanomaterials can take advantage of both luminescence and magnetism properties. The noble metal nanoparticals and carbon nanotubes（CNTs） can convert the absorption lights to heat through the photothermal conduction property. The multifunctional hybrid nanocomposites can simultaneously take advantage of magnetism, luminescence and photothermal properties and become ideal candidates for various further applications, such as cell imagings, biological sensor, targeted drug delivery, cancer treatment and so on.In this dissertation, we combined lanthanide ions doped fluoride nanomaterials(NaGdF₄:Yb³⁺, Er³⁺,Eu³⁺; NaGdF₄:Tb³⁺,Eu³⁺; NaGdF₄:Yb³⁺,Er³⁺), with multi-walled carbon nanotubes（MWCNTs） or Ag nanopartices to construct the multifunctional hybrid nanocomposites. We reported facile solution route to synthesize a series of multifunctional hybrid nanocomposites MWCNTs-NaGdF₄: Yb³⁺,Er³⁺,Eu³⁺; MWCNTs-NaGdF₄:Tb³⁺,Eu³⁺and Ag/NaGdF₄:Yb³⁺,Er³⁺. The structure, morphology, size and composition of the samples were characterized by X-ray diffraction（XRD）, scanning electron microscope（SEM）,energy-dispersive X-ray spectrometer（EDS） and fourier transform-infrared spectra（FT-IR）.The luminescence, magnetism and photothermal transduction properties were investigated by photoluminescence spectra（PL）, vibrating sample magnetometer（VSM） and photothermal transduction assay, respectively. At last, in order to examine the utility of nanocomposites in biological systems, the methyl thiazolyl tetrazolium（MTT） assay,inverted luminescence microscope imagings and the photothermal therapy assay were investigated. The results indicate that the as-prepared samples have favorable luminescence,magnetism, photothermal transduction properties, low toxicity, good biocompatibility,excellent luminescence imaging and favorable photothermal therapy effect. Therefore, the as-synthesized multifunctional hybrid nanocomposites have potential in biomedicine,environmental governance, fluorescence imaging.