Lin Hong-Jia, Tseng Po-Hsiang, Wu Wen-Chung
Department of Chemical Engineering, National Cheng Kung University, Tainan, 702, Taiwan.
Heliyon. 2024 Nov 29;10(23):e40786. doi: 10.1016/j.heliyon.2024.e40786. eCollection 2024 Dec 15.
Increasing attention has been paid to the detection of explosives due to the occurrence of terrorist attacks around the world. Here, we used free radical polymerization to develop two different types of fluorescent copolymers for use in detecting picric acid. One exhibits aggregation-caused quenching (ACQ) and is called PNNS [poly (-isopropyl acrylamide---hydroxymethyl acrylamide --styrene-pyrene), poly (NIPAAm--NMA--St-Py)]. The other possesses aggregation-induced emission (AIE) properties and is called PNNP [poly (-isopropyl acrylamide---hydroxymethyl acrylamide--2-(1,2,3,4,5-pentaphenyl-1H-silol-1-yloxy) ethyl methacrylate), poly (NIPAAm--NMA--PPS-HEMA)]. Nanofibrous thin films of these copolymers were obtained by electrospinning. Upon interaction with picric acid, the fluorescence intensity of each copolymer was quenched due to photo-induced electron transfer (PET). The average diameters of PNNS and PNNP nanofibers were 179 ± 28 nm and 235 ± 143 nm, respectively. Sensing performance was evaluated by Stern-Volmer analysis. The Stern-Volmer constant (K) values for PNNS and PNNP nanofibers were 0.012 μΜ and 0.119 μΜ, respectively. Since the aggregated state of PNNP nanofibrous thin films can increase dramatically, the AIE property of this material provides a large dynamic range. Finally, the reusability of water- and methanol-washed nanofiber thin films was tested, revealing that the nanofiber sensors were reusable for detecting picric acid.
由于世界各地恐怖袭击事件的发生，爆炸物检测受到了越来越多的关注。在此，我们利用自由基聚合反应开发了两种不同类型的荧光共聚物用于苦味酸检测。一种表现出聚集诱导猝灭（ACQ）特性，称为PNNS [聚（-异丙基丙烯酰胺-羟甲基丙烯酰胺-苯乙烯-芘），聚（NIPAAm-NMA-St-Py）]。另一种具有聚集诱导发光（AIE）特性，称为PNNP [聚（-异丙基丙烯酰胺-羟甲基丙烯酰胺-2-（1,2,3,4,5-五苯基-1H-硅杂环戊二烯-1-基氧基）甲基丙烯酸乙酯），聚（NIPAAm-NMA-PPS-HEMA）]。通过静电纺丝获得了这些共聚物的纳米纤维薄膜。与苦味酸相互作用时，由于光诱导电子转移（PET），每种共聚物的荧光强度都会猝灭。PNNS和PNNP纳米纤维的平均直径分别为179 ± 28 nm和235 ± 143 nm。通过Stern-Volmer分析评估传感性能。PNNS和PNNP纳米纤维的Stern-Volmer常数（K）值分别为0.012 μΜ和0.119 μΜ。由于PNNP纳米纤维薄膜的聚集态可以显著增加，这种材料的AIE特性提供了较大的动态范围。最后，测试了水洗和甲醇洗纳米纤维薄膜的可重复使用性，结果表明纳米纤维传感器可重复用于检测苦味酸。
