School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China.
School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China.
Anal Chim Acta. 2022 Oct 16;1230:340337. doi: 10.1016/j.aca.2022.340337. Epub 2022 Sep 9.
Considering that mercury ions (Hg) have long been a threat to human health and the environment due to their persistence, mobility and bioenrichment, the detection and removal of Hg is of great significance. Therefore, a simple water-soluble naphthalimide derived fluorescent dye with AIEE characteristics was reasonably constructed based on twisted intramolecular charge transfer (TICT) mechanism, a series of probes were synthesized to demonstrate this mechanism. The probe NIDEA (naphthalimide-diethanolamine) bonding Hg through the specific combination of the N-unsubstituted naphthalimide group and Hg to form a classic "imide-Hg-imide" structure. Moreover, the introduction of diethanolamine moiety enhanced the water-solubility of the probe, and also made the dye molecule possess the feature of AIEE. The fluorescence titration experiment showed that there were two good linear relationships between the fluorescence intensity of the probe NIDEA and the concentration of Hg in the range of 0-2.5 μM and 2.5-7.5 μM, and the limit of detection was 46.7 nM. Also, the probe could detect Hg in aqueous solution sensitively, ensuring its application in the actual water sample in the environment and living cells. At the same time, NIDEA can be used to detect Hg by Tyndall effect (TE) without limitation of instrument and technology, the limit of detection was 20.9 nM. Furthermore, this paradigm by introduction of the highly effective TICT structure supports a promising methodology for the construction of simple water-soluble AIE/AIEE-active probes.
考虑到汞离子（Hg）由于其持久性、迁移性和生物富集性，长期以来一直对人类健康和环境构成威胁，因此检测和去除 Hg 具有重要意义。因此，基于扭曲的分子内电荷转移（TICT）机制，合理构建了一种简单的水溶性萘酰亚胺衍生荧光染料，具有 AIEE 特性，合成了一系列探针来证明这种机制。探针 NIDEA（萘酰亚胺-二乙醇胺）通过未取代的萘酰亚胺基团与 Hg 的特异性结合，形成经典的“酰亚胺-Hg-酰亚胺”结构，从而与 Hg 键合。此外，二乙醇胺部分的引入增强了探针的水溶性，并且还使染料分子具有 AIEE 的特性。荧光滴定实验表明，探针 NIDEA 的荧光强度与 Hg 浓度在 0-2.5 μM 和 2.5-7.5 μM 范围内存在两个良好的线性关系，检测限为 46.7 nM。此外，该探针可以在水溶液中灵敏地检测 Hg，确保其在环境和活细胞中的实际水样中的应用。同时，NIDEA 可以通过 Tyndall 效应（TE）用于检测 Hg，不受仪器和技术的限制，检测限为 20.9 nM。此外，通过引入高效 TICT 结构，这种范例为构建简单的水溶性 AIE/AIEE 活性探针提供了一种有前途的方法。
