A Novel Fluorescence Sensor for Iodide Detection Based on the 1,3-Diaryl Pyrazole Unit with AIE and Mechanochromic Fluorescence Behavior

• Published in: Molecules (Basel, Switzerland) Vol. 28; no. 20; p. 7111
• Main Authors: Deng, Lili, Xiong, Jian, Liu, Wenqin, Wu, Lixue, Hu, Huiyi, Wu, Jiaqing, Liu, Yue, Yu, Lide, Zhou, Yuling, Gao, Wenjun, He, Haifeng, Yin, Weiyan
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.10.2023; MDPI
• Subjects: 1,3-diaryl pyrazole; AIE; Chromatography; Communication; Fluorescence; Hypothyroidism; Iodine; mechanochromic fluorescence; Nervous system diseases; sensor; Sensors; Thyroid gland; TPA-CDP; triphenylamine; China
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules28207111

A D−A type of luminophore, TPA-CDP, was designed and synthesized by using triphenylamine (TPA) as D (electron donor), 1,3-diaryl pyrazole with cyano groups (CDP) as A (electron acceptor) and employing a cyanovinyl segment as a recognition group. Firstly, TPA-CDP demonstrates effective fluorescence quenching as a sensor for I− by the nucleophilic addition reaction of the cyanovinyl segment with a high level of sensitivity, selectivity and a low determination limit of 4.43 μM. Interestingly, TPA-CDP exhibited an AIE phenomenon with the fw value reaching 50%. In addition, TPA-CDP displayed distinct mechanochromic fluorescence behavior with 70 nm red shift, which was observed over four repeated cycles. Furthermore, the mechanochromic fluorescence behavior of TPA-CDP, as observed in powder XRD experiments, was found to be associated with the morphological transition from a crystalline state to an amorphous state. These results confirm the significant potential of CDP as a powerful electron-deficient component in the creation of D−A-type mechanochromic fluorescence materials and biosensors for detecting I−.