School of Chemistry and Chemical Engineering, Jinggangshan University, Ji'an, Jiangxi 343009, China.
State Key Laboratory of Luminescent Materials & Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, College of Materials Science & Engineering, South China University of Technology, Guangzhou 510640, China.
Analyst. 2022 Sep 12;147(18):4132-4140. doi: 10.1039/d2an00850e.
Viscosity is one of the most important physical parameters in a liquid, noninvasive, and effective viscosity inspection method toward liquid safety that needs to be developed urgently. In this study, two kinds of novel molecular sensors, namely, DPBID and DPTMID, were strategically constructed by the triphenylamine indanedione derivates; the rotatable conjugate structure was utilized as the recognition site and fluorescence quencher. This couple of molecular sensors was synthesized in a one-step facile manner. DPTMID displayed longer emission wavelength and larger Stokes shift (195 nm in water, 138 nm in glycerol) with a narrower energy band. Moreover, DPTMID exhibited high selectivity, sensitivity, and significant fluorescence signal enhancement toward a higher viscous microenvironment. The molecular sensor displayed good photostability, selectivity, and universality in various commercial liquids and featured with typical aggregation-induced emission (AIE). With the aid of DPTMID, the thickening effects of liquid thickeners can be captured. More importantly, DPTMID was explored to visualize the viscosity fluctuations during the metamorphic stages of liquids, and it was found that the microenvironment viscosity level is closely related to the spoilage degree of liquids. The method with rapid detection, high sensitivity, cheap equipment, and fast results output toward food quality and safety inspection can be achieved through this study.
粘度是液体的最重要的物理参数之一，因此需要开发一种非侵入式且有效的粘度检测方法。在本研究中，我们通过三苯胺茚二酮衍生物构建了两种新型分子传感器，即 DPBID 和 DPTMID；利用可旋转的共轭结构作为识别位点和荧光猝灭剂。这对分子传感器通过一步简便的方法合成。DPTMID 具有更长的发射波长和更大的斯托克斯位移（在水中为 195nm，在甘油中为 138nm），并且具有更窄的能带。此外，DPTMID 对较高粘性的微环境表现出高选择性、灵敏度和显著的荧光信号增强。分子传感器在各种商用液体中表现出良好的光稳定性、选择性和通用性，具有典型的聚集诱导发射（AIE）特性。借助 DPTMID，可以捕捉到液体增稠剂的增稠效果。更重要的是，我们探索了 DPTMID 在液体的变态阶段期间可视化粘度波动的能力，结果发现微环境粘度水平与液体的变质程度密切相关。通过本研究，可以实现对食品质量和安全检测的快速检测、高灵敏度、低成本设备和快速结果输出的方法。
