Quantum dots as a novel nano semiconductor material,compare to the traditional organic fluorescent dye, quantum dots has its own special fluorescent properties,broad excitation but narrow emission. Quantum dots aslo has strong stablity of resisting photobleaching. In recent years, quantum dots has been widely used in biological label,sensor and any other field. This experiment choosing glutathione (GSH), thiolglycollic acid (TGA) as capping reagents has prepared carboxylated water-soluble GSH-CdTe quantum dots (QDs) by One-Pot reaction in aqueous phase. Contrast to ligand TGA, GSH@CdTe QDs exhibit high stability to higher concentration of EDTA. We have prepared GSH@CdTe QDs biological sensor according to its fluorescence quenching to detect pH of different PBS buffer and the concentration of copper ions. GSH@CdTe QDs biological sensor can detect pH value from 4 to 10, and the limits concentration of Cu2+ is from 0.3125μM to 10μM Another experiments,we have detected AuNPs self assembly which gave rise to "click" chemistry. First, we react the polymer coated AuNPs with 5K terminal azide PEG and 5K terminal alkyne PEG in EDC reaction. And then do "click" chemistry, choose copper(I) and ascoribic acid as catalyst. After "click" chemistry as the crosslinking of AuNP, we can see precipitate in the bottom of reaction solution, most important according to precipitate, we can detect the concentration of Cu2+ in solution. |