Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Guangdong Engineering Technology Research Center for High-Performance Organic and Polymer Photoelectric Functional Films, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China.
National Engineering Research Center for Healthcare Devices, Guangdong Key Lab of Medical Electronic Instruments and Polymer Material Products, Guangdong Institute of Medical Instruments, Guangzhou 510500, China.
Sensors (Basel). 2019 Mar 25;19(6):1455. doi: 10.3390/s19061455.
Förster resonance energy transfer (FRET)-based polymer dots (Pdots), fabricated by semiconducting polymers and exhibiting excellent properties, have attracted much interest in the last decade, however, full polymer-dot-based pH sensors are seldom systematically exploited by researchers. In this work, we constructed a kind of blend polymer dot, utilizing poly[(9,9-dihexyl-9H-fluorene-2,7-vinylene)-co-(1-methoxy-4-(2-ethylhexyloxy)-2,5-phenylenevinylene)] (PFV) as the donor, poly[2,5-bis(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (BDMO-PPV) as the acceptor, and polysytrene graft EO functionalized with carboxy (PS-PEG-COOH) to generate surface carboxyl groups. This type of Pdot, based on the FRET process, was quite sensitive to pH value changes, especially low pH environments. When the pH value decreases down to 2 or 1, the fluorescence spectrum of Pdots-20% exhibit spectral and intensity changes at the same time, and fluorescence lifetime changes as well, which enables pH sensing applications. The sharpening of the emission peak at ~524 nm, along with the weakening and blue shifts of the emission band at ~573 nm, imply that the efficiency of the energy transfer between PFV and BDMO-PPV inside the Pdots-20% decreased due to polymer chain conformational changes. The time-resolved fluorescence measurements supported this suggestion. Pdots constructed by this strategy have great potential in many applications, such as industrial wastewater detection, in vitro and intracellular pH measurement, and DNA amplification and detection.
基于Förster 共振能量转移（FRET）的聚合物点（Pdots）由半导体聚合物制成，具有优异的性能，在过去十年中引起了广泛关注，然而，全聚合物点基 pH 传感器很少被研究人员系统地开发利用。在这项工作中，我们构建了一种共混聚合物点，利用聚[(9,9-二己基-9H-芴-2,7-亚乙烯基)-共-(1-甲氧基-4-(2-乙基己氧基)-2,5-亚苯基亚乙烯基)]（PFV）作为供体，聚[2,5-双（3',7'-二甲氧基辛基）-1,4-亚苯基亚乙烯基]（BDMO-PPV）作为受体，并利用聚硅氧烷接枝乙氧基官能化的羧基（PS-PEG-COOH）生成表面羧基。这种基于 FRET 过程的 Pdot 对 pH 值变化非常敏感，特别是在低 pH 环境下。当 pH 值降低到 2 或 1 时，Pdots-20%的荧光光谱在同一时间同时显示光谱和强度变化，以及荧光寿命变化，这使其能够进行 pH 感应应用。524nm 处发射峰的锐化，以及573nm 处发射带的减弱和蓝移，表明由于聚合物链构象变化，PFV 和 BDMO-PPV 之间的能量转移效率在 Pdots-20%内部降低。时间分辨荧光测量支持了这一观点。通过这种策略构建的 Pdots 在许多应用中具有很大的潜力，例如工业废水检测、体外和细胞内 pH 测量以及 DNA 扩增和检测。
