Preparation,separation And Application Of Carbon Dots Based On Biomass Garlic

Carbon dots（CDs）is a kind of carbon nano material with small size（less than10nm）and unique fluorescence properties.It has been widely used in the fields of biological imaging,analysis and detection,photocatalysis,photoelectric materials and so on because of its easy preparation,good dispersion,photobleaching,and low biological toxicity.In addition to some carbon nanomaterials and organic reagents containing carbon,many natural biomass materials can also be used as raw materials to prepare CDs.These biomass carbon sources are green,pollution-free,cheap and easy to obtain.N,S and other elements and some active functional groups in thses biomass materials can be retained in the CDs,which can not only obtain highperformance carbon dots,but also improve the application value of biomass materials.However,no matter what kind of carbon source is used,most of the carbon dots are mixtures with different sizes and structures.Their interaction leads to the lower fluorescence quantum yield,which greatly limits the application effect of carbon dots in many fields.Therefore,how to improve the fluorescence quantum yield of carbon dots is still one of the key scientific issues in the field of carbon dots research.In this paper,natural biomass materials were selected as carbon source to synthesize fluorescent carbon dots.Through separation and purification,the fluorescence quantum yield of carbon dots was effectively improved,and the application of carbon dots in metal ion detection and fluorescent biological probes was further discussed.The specific work is as follows:1.A kind of fluorescent CDs was synthesized by hydrothermal method with garlic as carbon source.The morphology and properties of CDs were characterized by means of TEM,IR,UV,fluorescence and X-ray diffraction.2.The CDs were separated and purified by column chromatography.The structural characteristics and stability of the separated carbon dots were further investigated.3.The influence of common metal cations,anions and amino acids on the fluorescence characteristics of CDs was investigated.A method for the specific detection of Fe³⁺was established by fluorescence quenching of CDs.The detection limit and linear range of the detection were determined,and the mechanism was discussed.4.A new type antibody protein Ki67-CDs fluorescent probe was prepared by using EDC as coupling agent.The optimal preparation conditions and cytotoxicity of the probe were also investigated.