ZnS∶Cu-罗丹明B的荧光共振能量转移性质

Properties of Fluorescence Resonance Energy Transfer of ZnS∶Cu-Rhodamine B

为了解决现有的基于量子点荧光共振能量转移体系的生物毒性问题,选用无毒的ZnS∶Cu量子点与罗丹明B构建新型荧光共振能量转移体系。通过共沉淀法成功制备了形貌均一的ZnS∶Cu纳米晶量子点。在此基础上,测试了不同掺杂浓度的ZnS∶Cu量子点及罗丹明B的荧光光谱。然后,通过对ZnS∶Cu量子点的表面修饰构建了以ZnS∶Cu量子点为供体、罗丹明B为受体的荧光共振能量转移体系。实验结果表明:ZnS∶2%Cu量子点的发光光谱与罗丹明B的吸收光谱在481 nm处有较大重合,说明构建荧光共振能量转移的最佳铜掺杂摩尔分数为2%。通过计算发现以ZnS∶2%Cu量子点为供体、罗丹明B为受体的荧光共振能量转移体系的能量转移效率为25.8%。进一步实验结果表明,罗丹明B浓度也能够影响能量转移。

In order to solve the biological toxicity of fluorescence resonance energy transfer （FRET） system based on quantum dots, non-toxic ZnS∶Cu quantum dots and Rhodamine B were chosen to construct FRET system.ZnS∶Cu nanocrystalline quantum dots with good morphology were successfully prepared by precipitation method.On this basis, the fluorescence spectra of ZnS∶Cu quantum dots with different concentration of copper and fluorescence spectra of Rhodamine B were tested.Then, FRET system with ZnS∶Cu quantum dots as donor and Rhodamine B as acceptor was successfully constructed by the surface modification.Experimental results indicate that the emission spectrum of ZnS∶2%Cu matches the excitation spectrum of Rhodamine B most in 481 nm.So the optimum copper doping mole fraction for the construction of FRET system is 2%.The energy transfer efficiency of ZnS∶Cu quantum dots as donor and Rhodamine B as acceptor is 25.8%.Further experimental results indicate that the concentration of Rhodamine B also can affect the energy transfer.