Studies On The Synthesis Of Water-soluble Quantum Dots Modified By PEG And The Interaction With Peptide

The important application of Semiconductor dots(QDs) in the biomedical has been investigated mostly during recent years. The combination of Quantum dots and biotechnology, not only has greatly promoted the development of the biological area, but also make people pay more attention to the nature of quantum dot self-optimization problem ,for example, water solubility,biocompatibily,and toxicity. In this work, we focuses on the synthesis,modification,application of quantum dots.The detail contents and results are as follows:1. Fuorescent CdTe QDs stabilized by thioglycolic acid(TGA) were prepared in aqueous solution and then encapsulated with mPEG-SH(MW5000) successfully. PEG encapsulation can also reduce toxicity and increase stability。The interaction between CdTe-PEG conjugation and Peptide(including the concentration of peptide ,PH value,reaction tempreture and incubate time)was systematically studied. The interaction mechanism was also discussed.2. We prepared the core-shell CdTe/CdS, CdTe/CdS/ZnS quantum dots in solution directly. compared to CdTe QDs, the core-shell CdTe/CdS, CdTe/CdS/ZnS quantum dots has good stability and high quantum yield. The nanostructures of core shell quantum dots were characterized by X-ray diffraction (XRD) and X-Ray Photoelectron Spectroscopy(XPS). By using the method of plate culture count we evaluated the toxicity of quantum dots.It demonstrates that ZnS shell can reduce toxicity of quantum dots to a large extent. Core-shell quantum dots might be conveniently applied in biological field.