Synthesis,Characterization And Application Of Carbon Nanoparticles Derived From Natural Sugars

The shortcomings of traditional organic fluorescent dyes,such as poor light stability and easy quenching,bring a lot of inconvenience to the actual research work.So finding a new type of fluorescent material becomes a research focus.Although quantum dots have many good fluorescence properties,they contain toxic heavy metals,this limits their fully utilization in some degree.Sun's research group reported surface passivated carbon nanoparticle could emit visible light,creating a new era.Fluorescent carbon nanoparticle is a kind of environment-friendly biological markers.Compared with the organic dye,carbon nano-particles have lots of good characteristics including high light stability,strong resistance to photobleaching,good biocompatibility,low toxicity and light cell damage,it has an unique advantage in vivo biomarkers.Therefor,carbon nanoparticle is expected to replace quantum dots for live cell labeling image and animal vivo image,which attracted the researchers' great interest.In the future,fluorescent carbon nanoparticles will be an ideal biological fluorescent labeling materials,it provides a new area for the new luminescent carbon nanoparticle.The main work of this paper are as follows:The preparation of fluorescent carbon nanoparticles(CNPs):the fluorescent CNPs were prepared using cellulose,chitosan,cyclodextrin and starch by a facile hydrothermal oxidation method.The characterization of carbon nanoparticles(CNPs):the characterizations by transmission electron microscopy showed that the prepared cellulose-CNPs,chitosan-CNPs,cyclodextrin-CNPs and starch-CNPs were spherical,well-dispersed in water with average diameters of 75 nm,100 nm,76 nm and 14 nm seperately.Under the excitation of UV light,the CNPs were strongly luminescent with an excitation-dependent emission behavior and bathochromic emission properties.Their light stability was better than fluorescein and Rhodamine.Carbon nanoparticles had strong near-infrared fluorescence under 633 nm excitation light.The application of carbon nanoparticles(CNPs):carbon nanoparticles with negative electricity combined with metal ion with positive electricity through electrostatic interaction.Then the fluorescence of carbon nanoparticle had been quenched especially.Cu(?),Hg(?)and Fe(?)had greater effection.I/I0 values were linear relationship with Fe(III)concentration in some degree.The carbon nanoparticles were used for cell labeling and fish vivo imaging.The experimental results showed that cel-CNPs were lighter.Then the carbon nanoparticles fed to fish could enter the vivo for imaging and had strong fluorescence.