Controllable Synthesis, Surface Modification Of Functional Nanomaterials And Their Fluorescence Labeling And Cytotoxicity Study

With the rapid development of nanotechnology and wide application of nanomaterials, quantum dots (QDs), magnetic Fe3O4, nano gold, cerium oxide, carbon nanotubes grapheme and so on functional nanomaterials are already widely applied in the biomedical field. Among these functional nanomaterial, quantum dots and cerium oxide are particularly concerned. Just aiming at this important research direction, based on a survey of a large number of documents, by means of electrophoresis analysis techniques, MTT method and anti-oxidation test (SOD and GSH), the controllable synthesis, surface modification of functional nanomaterial (quantum dots and cerium oxide) and their fluorescence labeling and cell cytotoxicity study are carried out. Content of specific sections of the paper are described below.In the first chapter, for the frontier and hot of quantum dots fluorescent labels at highly sensitive, in situ, real-time, dynamic, the paper summarizes the research progress of quantum dot fluorescent labels in the cell and tissue imaging, targeted drug, DNA molecular testing aspects. Considering the nanocerium oxide with the unique feature at storing and releasing oxygen, catalytic/regenerative properties, the article sums up the research progress of nanocerium oxide in the biomedical field at radical scavenging, antioxidant activity, tumor markers and targeted drugs. Based on these two functional nanomaterials in fluorescent markers and antioxidant aspects of the application, the research concent and innovation also is come up with.In the second chapter, based on "Oswalt" ripening principle, size-controlled CdSe quantum dots were synthesized by use of "reverse injection method" in the high temperature of the oil phase and N2protection conditions. Then core and shell CdSe@Zns QDs were prepared through coating the wide level nanomaterials ZnS on the surface of CdSe quantum dots. In order to enhance biocompatibility of CdSe@Zns QDs, a kind of two dear of polymer materials was modified on the surface of CdSe@Zns QDs, which make the fat-soluble quantum dots conver to water-soluble quantum dots. The obtained QDs with excellent solubility could be further functional assembled.In the third chapter, DNA molecules labeled with quantum dots is the main content. Because the oligonucleotide molecule probe needs special design, its cost is high. While conventional organic fluorescent small molecule and biotin are instability, at the same time, conventional radioisotope labeling has radiation. In order to obtain an inexpensive and convenient method of fluorescently labeled DNA molecules, we try to label DNA molecules obtained by PCR technology by means of quantum dot.In the fourth chapter, controllable synthesis and surface modification of nanoceria are the main content. Nanoceria’s phase composition, morphology, size, valence, and the charge properties of surface functional groups were analyzed in great detail by X-ray powder diffraction (XRD), Transmission electron microscopy (TEM), X-photoelectron spectroscopy (XPS), Fourier transform microscopy infrared spectrometer (FT-IR), UV-vis absorption (UV-vis) and Zeta potential technologies. In this part of work, it corfirms an effective method, which could prepare ultrafine monodisperse and soluble nanoceria modified with functional group. Furthermore these nanoceria particles are completely in conformity with the requirements of biomedical field and established the foundation for the next test in vitro.In the fifth chapter, the cell cytotoxicity and antioxidant property of ultrafine monodisperse nanoceria are the main content. Cell morphology, antioxidant property and cell intake are analyzed by use of Scanning electron microscope (SEM), Transmission electron microscopy (TEM), MTT assay, GSH, SOD and Flow Cytometric assay (FCA) after the BGC-803cells and ultrafine monodispersed nano ceria interact. In this work, we explored the relationship between the soluble property, chemical valence, surface functional groups of nanoceria and the cytotoxicity and antioxidant properties of BGC-803cells, which could be benefit for determining the law between the chemical composition and valence state, size and morphology, surface charge and surface coating, agglomeration state of cerium oxide nanoparticles and cytotoxicity of BGC-803cells, revealing the incentive of oxidative stress in BGC-803cells. This work could provide experimental data for the study of cerium oxide nanoparticles in antioxidant drugs and could help to carry out light rare earth cerium oxide’s application of the biomedical field in Inner Mongolia region.