School of Pharmacy, Henan University of Chinese Medicine, Zhengzhou 450046, PR China.
School of Pharmacy, Henan University of Chinese Medicine, Zhengzhou 450046, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2019 Dec 5;223:117334. doi: 10.1016/j.saa.2019.117334. Epub 2019 Jul 2.
Hypochlorous acid (HClO) is an important reactive oxygen species (ROS) and plays a significant role in living organisms. Highly selective and lysosome-targetable probes for sensing hypochlorous acid are rare. In this article, we designed and prepared a new lysosome-targeting and ratiometric fluorescent probe for monitoring the levels of hypochlorous acid. 4-Aminonaphthalimide was chosen as the fluorescent group and (2-aminoethyl) thiourea group was used as a specific recognition group for HClO. A morpholine unit was employed as a lysosome-targeting group. In the absence of HClO the probe underwent intramolecular charge transfer (ICT) and showed a green emission. When excess HClO is present, the ICT process was interrupted which caused a 57 nm blue-shift of fluorescence emission from 533 nm to 476 nm. The ratiometric fluorescent probe showed outstanding selectivity toward HClO over other various bioactive species. Furthermore, the ratiometric fluorescent probe exhibited rapid response time and ability of working in a wide pH range. The linear response of I/I toward HClO was obtained in a concentration range of HClO from 1.0 × 10 to 1.0 × 10 mol·L. The detection limit was estimated to be 8.0 × 10 mol·L for HClO. Moreover, the probe showed a perfect lysosome-targeting ability, and has been successfully used to the confocal imaging of HClO in lysosomes of HepG2 cells with little cell toxicity. All of such good properties illustrated that it could be applied to determine HClO at lysosomes in living cells.
次氯酸（HClO）是一种重要的活性氧物质（ROS），在生物体内发挥着重要作用。高选择性和溶酶体靶向的次氯酸检测探针非常罕见。在本文中，我们设计并制备了一种新的用于监测次氯酸水平的溶酶体靶向和比率荧光探针。4-氨基萘二酰亚胺被选为荧光团，（2-氨乙基）硫脲基团被用作 HClO 的特异性识别基团。一个吗啉单元被用作溶酶体靶向基团。在没有 HClO 的情况下，探针经历分子内电荷转移（ICT），并显示出绿色发射。当存在过量的 HClO 时，ICT 过程被中断，导致荧光发射从 533nm 蓝移至 476nm。比率荧光探针对 HClO 具有出色的选择性，超过了其他各种生物活性物质。此外，比率荧光探针表现出快速的响应时间和在宽 pH 范围内工作的能力。在 HClO 的浓度范围为 1.0×10 至 1.0×10 摩尔·L 时，I/I 对 HClO 的线性响应得到了。HClO 的检测限估计为 8.0×10 摩尔·L。此外，该探针表现出完美的溶酶体靶向能力，并已成功用于 HepG2 细胞溶酶体中 HClO 的共聚焦成像，细胞毒性很小。所有这些良好的性质表明，它可以应用于测定活细胞溶酶体中的 HClO。
