Study On Preparation And Properties Of Magnetic Fluorescent Mulfunctional Nanospheres

Stimuli-responsive nanospheres, which have the ability to change the physical-chemical and colloidal properties in response to small external stimuli from the external environment such as temperature, pH, chemicals, light, electrical field, magnetic field, mechanical stress, etc., have promising applications in biomedical and biotechnological fields such as delivery of therapeutic agents, separation of biomacromolecules, cell labeling and sorting, bioimaging, as well as simultaneous diagnosis and therapy. Magnetic, luminescent, and thermo-sensitive nanomaterials, due to integrate various functional nanomaterials function-related components into a single entity, has great prospects of the development of science and technology research and huge potential in the field of multi-function imaging research.As clinical science developing, the single function of nanometer materials have already can’t satisfied requirement, many researched have shown that research and development will be the focus on the functional nanomaterials in future. Magnetic fluorescent and temperature-sensitive polymer materials are a kind of multifunctional nanopheres, which exhibit excellent applications in optical/MRI resonance imaging, temperature-sensitive, and so on. In our work, the luminescence complexes monomer was firstly prepared, and then the multifunctional nanospheres were prepared by soap-free emulsion polymerization. The test results showed that the prepared nanospheres have excellent superparamagnetic, thermosensitive, and fluorescent properties, which means render the useful in biomedical engineering and optical imaging(1) The multifunctional nanopheres Fe3O4/Poly(MMA-NIPAM-Tb(AA)3Phen) were synthesizedby successfully by soap-free emulsion polymerization, and characterization of particle size, chemical structure and composition, fluorescence and magnetic, as a optical/magnetic resonance imaging (MRI) probe, studied the nanospheres accumulated in rats in vivo imaging effect and distribution. The results show the multifunctional nanospheres with a size between 140nm and 220 nm, which exhibits strong green fluorescence of the rare earth complex Tb(AA)3Phen, the green fluorescence is more easily distinguish by human eyes. Most importantly, the intensities of Tb(AA)3phen remain almost constant after reaching the maximum. The in vivo, in vitro and fluorescence imaging test of nanospheres indicate it with good imaging effect in liver and spleen tissues of mouse. The photoluminescence stability offers not only a wide window for practical consideration for potential applications but also an insight into nanoparticles design of advanced systems.(2) The nanopheres Fe3O4/Poly(MMA-HEMA-Eu(AA)3Phen) were synthesized successfully. The experiment results indicating that the nanospheres were as our expected, TEM images reveal that the bifunctional nanospheres have core-shell structure, in a spherical shape with a size ranging from 140 to 180 nm. In MRI experiment, a clear negative contrast enhancement in T2 images and the T2 reaches 568.82mM-1s-1. In vivo magnetic and fluorescence resonance imaging results, suggesting the nanospheres are able to preferentially accumulate in liver and spleen tissues to allow dual-modal detection of cancer cells in a living body.