Department of Chemistry, BITS-Pilani, Hyderabad Campus, Shameerpet, Hyderabad, Telangana 500078, India.
Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.
ACS Appl Bio Mater. 2021 Sep 20;4(9):6893-6902. doi: 10.1021/acsabm.1c00600. Epub 2021 Aug 10.
An amphiphilic chromogenic probe based on an oxidized di(indolyl)arylmethane backbone has been utilized for visual detection of both Cu (detection limit = 8.5 ppb) and Hg (detection limit = 10.2 ppb) ions via mutually independent sensing pathways. The Cu ion binds to the carboxylate ends (donor site) and induces a color change from orange to yellow in the aqueous medium, while coordinating Hg at the bisindolyl moiety (acceptor site) can result in the formation of a red-colored solution. Interestingly, by selecting the proper excitation channel, we can specifically excite either the monomer species or nanoaggregates. The addition of Hg enhances the monomer fluorescence, while Cu induces quenching. However, in both cases, metal-ion coordination triggers dissociation of a preformed self-assembled structure. Further, the in-situ-formed Cu(II) complex was utilized for rapid, on-location detection of food-borne pathogens, such as () in contaminated food items and water (detection limit = 52 CFU·mL). induces reduction of Cu to Cu and transforms the yellow-colored solution into an orange-colored solution. Finally, low-cost, reusable paper strips were designed as an eco-friendly, sustainable strategy to detect bacterial pathogens.
一种基于氧化双（吲哚基）芳基甲烷骨架的两亲显色探针已被用于通过相互独立的传感途径可视化检测 Cu（检测限=8.5 ppb）和 Hg（检测限=10.2 ppb）离子。Cu 离子与羧酸盐末端（供体部位）结合，并在水介质中诱导颜色从橙色变为黄色，而在双吲哚部分（受体部位）与 Hg 配位可以导致形成红色溶液。有趣的是，通过选择适当的激发通道，我们可以特异性地激发单体物种或纳米聚集体。Hg 的加入增强了单体的荧光，而 Cu 则导致荧光猝灭。然而，在这两种情况下，金属离子的配位都会触发预形成的自组装结构的解离。此外，原位形成的 Cu(II) 配合物可用于快速、现场检测食源性病原体，例如在污染食品和水中的 （检测限=52 CFU·mL）。 诱导 Cu 还原为 Cu，并将黄色溶液转化为橙色溶液。最后，设计了低成本、可重复使用的纸条作为一种环保、可持续的策略来检测细菌病原体。
