Preparation Of Three Kinds Of Carbon Dots And The Application In Detection Of Medicine And Cr（Ⅵ）

Fluorescent carbon dots（CDs）are a kind of small size carbon nanomaterials.It has the advantages of small size,good stability,can emit different colors of light,and good biocompatibility.Therefore,carbon dots are used in many fields,such as biology Cell imaging,biosensors,solar cells,medical treatment,medicine,etc.In this paper,three kinds of fluorescent carbon dots were successfully prepared by microwave method and applied to the detection of oxytetracycline,chlortetracycline,and Cr（Ⅵ）ion.The specific research content is as follows:（1）Using p-phenylenediamine,phloroglucinol and hydrogen peroxide as raw materials,synthesize CDs by microwave method,and optimize the synthesis conditions of CDs,such as synthesis temperature,synthesis ratio,and microwave power selection,etc..Then,the prepared CDs were characterized by ultraviolet absorption spectroscopy,Fourier infrared spectroscopy and transmission electron microscopy.The results show that in the concentration range of oxytetracycline 25-200μmol/L,the fluorescence intensity difference of CDs has a good linear relationship with the concentration of oxytetracycline,and the detection limit is1.70×10^-5mol/L.Based on this,the above The prepared CDs were successfully used for the detection of oxytetracycline.（2）Using o-phenylenediamine and nitric acid as raw materials,using the microwave method,CDs were synthesized by optimizing the synthesis temperature,synthesis ratio and selection of microwave power.As the concentration of chlortetracycline increases,the fluorescence of CDs is quenched,and there is a good linear relationship between the difference in fluorescence intensity of CDs and the concentration of chlortetracycline（2-100μmol/L）,and the detection limit is 1.60×10^-6mol/L Compared with CDs synthesized from p-phenylenediamine,phloroglucinol and hydrogen peroxide,the CDs prepared by this method are more sensitive to the detection of chlortetracycline.（3）Using p-phenylenediamine,hydroquinone and hydrogen peroxide as raw materials,by optimizing the synthesis temperature,synthesis ratio and selection of microwave oven power,Huaqing CDs were synthesized.The addition of Cr（Ⅵ）can quench the fluorescence of CDs.When the concentration range of Cr（Ⅵ）is 10-200μmol/L,there is a good linear relationship between the fluorescence intensity difference of CDs and the concentration of Cr（Ⅵ）,and the detection limit is 5.60×10^-6mol/L.It can be seen that the newly prepared CDs have been successfully applied to the determination of Cr（Ⅵ）content in environmental water samples.