中文摘要：

以巯基乙酸为稳定剂,在水相中直接合成表面带负电荷,具有良好的分散性CdS量子点.利用CdS量子点、γ-氨基丙基三乙氧基硅烷和壳聚糖之间的静电吸引相互作用,在石英表面通过层层组装,构筑多层CdS量子点纳米薄膜.采用荧光光谱、荧光显微镜对Quartz/APES/CdS量子点自组装膜进行表征,并将该膜用于对DNA的界面荧光传感.研究表明,自组装膜的荧光强度随着DNA浓度的增大而减弱,且在一定范围内呈良好的线性关系,其相关系数为0.996 17,检测限为38.6ng.L-1,可实现对DNA的定量测定.

英文摘要：

CdS quantum dots（QDs） was synthesized directly in aqueous solution stabilized by thioglycolic acid.The CdS QDs was assemblied onto the surface of quartz substrate by the electrostatic interaction between the CdS QDs,γ-aminopropyl-triethoxysilane and chitosan,and CdS QDs nanofilm was constructed with layer by layer assembly technique.The obtained self-assemble multilayer film was characterized by fluorescence spectra and fluorescence microscope.Further,the self-assembled multilayer film could be used as a fluorescence sensor for DNA.Experimental investigation shows that the fluorescence intensity of the Quartz/APES/CdS SAMs decreased with the increase of the concentration of DNA,and displayed a good linear relationship within a certain concentration.In addition,the correlation coefficient was 0.996 17,and the detection limit was as low as 38.6 ng·L-1,qualifying the monolayer very useful in detection of DNA.