| The rapid progress of nanoscience and nanotechnology in past decade has made itself being widely applied into many other subjects, and caused the formation of a series of independent but close related interdisciplinaries. Bionanomedicine, which is composed by nanoscience, biology, medicine, is one of the most shining and active research field. One major content of it is the preparation and application of functional biomedical materials. One kind which were mainly used as tags are mostly researched and used because of their stability, high sensitivity, easy to be controlled and convenience in use. Among which, Quantum dots (QDs) are abroad in the researches such as preparation and imagining of fluorescence probes, Fluorescence Energy Transfer (FRET) and so on for their extraordinary nanofluorescence effect. Ferromagnetic nanomaterials have been successfully applied in diagnose and treatment of illness, and the separation of biological substance for their small radius and excellent maneuverability.The core/chell structured QDs were needed in practical application. The commonly used routes for the preparation of such QDs are toxic, explosive or too complex to control. On the other hand, fluorescence label and separation are daily operation in biomedical research. How to integrate these two kind nanomaterials into one and make it could conjugate with specific substance is a very interesting but challenging question. This thesis report the work as the following: 1) The simple salts such as acetic cadmium, acetic zinc etc were adopted to prepare II-VI core/shell structured QDs, for example, CdSe/ZnS, CdSe/CdS. The results of transmission electronic microscope (TEM), UV-Vis absorption spectrum, fluorescence spectrum show that the product is of excellent crystal structure, monodispersivity, uniform in radius, size controllable, with extraordinary fluorescence characteristic, the quantum yield has increased 30%-50%compared with bare CdSe QDs. This method is safe,cheap, repeatable, and convenient to operate, without special facilities, so it is possible to be performed on a multigram scale. 2) Modify the core/shell structure QDs by simple mechanical rubbing strategy to convert them from hydrophobic to hydrophilic. The observation by atomic force microscope and fluorescence microscope indicate that the product (BSA-QDs) remains good monodispersivity and fluorescence characteristic. Satisfied result has been gotten by using BSA-QDs as selective probe to detect Cu2+in water solution. 3) A new kind route of high-temperature decomposition in organic phase has been used to get nano-r-Fe2O3, which is uniform in radius, both monodisperse and superparamagnetic. This route is safe, cheap, and convenient. 4) The polystyrene, styrene-acrylamide copolymer nanospheres that are both uniform in radius and surface clean were prepared by free-emulsion method. And on this base, the core/shell structured quantum dots and nano-r-Fe2O3 were co-embedded into nanospheres to fabricate a series new type fluorescent-magnetic biofunctional nanomaterials, and they were characterized by scanning electron microscope, High-resolution TEM, energy dispersive X-ray microanalysis etc. What's more, the folic acid was conjugated to the surface of the biofunctional nanomaterials to get cancer cell-target nanobiodevice, and they were used to recognize Hela, MCF-7 cancer cells. These work make solid foundation for the future work of simultaneous visual recognize and separation of multi-kind target cells.
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