Fan Enze, Guo Huiying, Hao Tingting, Zhao Ronghui, Zhang Pengfei, Feng Yayu, Liu Yunfei, Deng Kuilin
Key Laboratory of Analytical Science and Technology of Hebie Province (Project Number: 22567620H), College of Chemistry and Materials Science, Hebei University, Baoding 071002, China.
Key Laboratory of Analytical Science and Technology of Hebie Province (Project Number: 22567620H), College of Chemistry and Materials Science, Hebei University, Baoding 071002, China; Department of Clinical Pharmacy, Affiliated Hospital of Hebei University, Baoding 071002, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2024 Mar 15;309:123782. doi: 10.1016/j.saa.2023.123782. Epub 2023 Dec 16.
In this work, three morpholine-modified polyacrylamide derivatives (MMPAm) were successfully prepared by free radical polymerization of monomers with morpholine moiety. The intramolecular aggregation of morpholine rings on macromolecular backbone gives MMPAm a significant polymerization-induced emission (PIE). Particularly, poly(N-morpholine acrylamide) (PNMPA) has the characteristics of strong fluorescence at 450 nm, and its fluorescence quantum yield reaches 2.87 %. The introduction of morpholine moiety, the length of CH spacer between morpholine ring and the backbone and the molecular weight play the important roles in PIE properties of PNMPA. Interestingly, PNMPA can recognize and detect Cu specifically even in the presence of 12 other metal ions by thorough fluorescence quenching, and the detection limit of PNMPA is 17.3 μM. Furthermore, the dynamic quenching of PNMPA by Cu ions and the complexation ratio of 1:2 according to JOB's working diagram were confirmed by fluorescence titration. Under the assistance of EDTA, a reversible detection system for Cu is achieved, and a portable test paper from PNMPA for the detection of Cu was also made. In conclusion, PNMPA is endowed with a significant PIE effect by the intramolecular aggregation of morpholine rings along the backbone in the polymerization of non-fluorescent monomer, and is expected to be a promising material for specific detection to Cu ions.
在本工作中，通过含吗啉部分的单体的自由基聚合成功制备了三种吗啉改性的聚丙烯酰胺衍生物（MMPAm）。吗啉环在大分子主链上的分子内聚集赋予MMPAm显著的聚合诱导发光（PIE）。特别地，聚（N-吗啉丙烯酰胺）（PNMPA）在450nm处具有强荧光特性，其荧光量子产率达到2.87%。吗啉部分的引入、吗啉环与主链之间CH间隔基的长度以及分子量在PNMPA的PIE性质中起重要作用。有趣的是，即使在存在12种其他金属离子的情况下，PNMPA也能通过完全荧光猝灭特异性地识别和检测Cu，并且PNMPA的检测限为17.3μM。此外，通过荧光滴定证实了Cu离子对PNMPA的动态猝灭以及根据Job工作曲线得到的1:2的络合比。在EDTA的辅助下，实现了对Cu的可逆检测系统，并且还制备了用于检测Cu的PNMPA便携式试纸。总之，在非荧光单体聚合过程中，吗啉环沿主链的分子内聚集赋予PNMPA显著的PIE效应，并且有望成为用于特异性检测Cu离子的有前途的材料。
