基于水溶性CdTe量子点-绿原酸-血管紧张素Ⅰ相互作用的荧光可逆调控

摘要

在水相中合成了巯基丙酸( MPA)包覆的CdTe量子点(QDs),采用透射电子显微镜和原子力显微镜对其进行表征.利用荧光光谱、紫外-可见吸收光谱和红外光谱研究了CdTe QDs与绿原酸(CHA)的相互作用.结果表明,CHA可显著猝灭CdTe QDs的荧光,在一定的浓度范围内,荧光猝灭值与CHA的浓度呈现一定的线性关系.推断其主要猝灭机理为动态猝灭,并实现了荧光光谱法测定CHA.向CdTe QDs-CHA体系中加入血管紧张素Ⅰ (Ang Ⅰ)后,CdTe QDs荧光在一定浓度范围内逐渐恢复,从而实现了CdTe QDs的荧光可逆调控.CdTe QDs荧光的猝灭与恢复过程对于荧光传感的设计以及荧光可逆调控机理的研究具有指导意义.%Using mercaptopropinic acid( MPA) as the stabilizer, CdTe quantum dots( QDs) were synthesized in aqueous solution. Their particle sizes and morphology were characterized by transmission electron micro-scope(TEM) and atomic force microscope (AFM). Chlorogenic acid(CHA) can quench the fluorescence of CdTe QDs effectively, and the quenching values of fluorescence were proportional to the concentration of CHA in a certain concentration range. The interaction between CdTe QDs and CHA was investigated via fluorescence spectrometry, UV-Vis absorption spectrometry and Fourier transform infrared spectrometry. The preliminary judgement of the quenching mechanism is dynamic quenching, and a theoretical basis of fluorescent spectrometry methods for the determination of trace amounts of CHA was provided. When angiotensin I human acetate salt hydrate(Ang I ) was added into the CdTe QDs-CHA system, the fluorescence of CdTe QDs was recovered in a certain concentration range, thus reversible control of fluorescence of the QDs was realized. The process of fluorescent quenching and recovering of CdTe QDs has a guiding significance for the design of fluorescence sensor and the study of mechanism of reversible control of fluorescence.