Key Laboratory of Functional Nanomaterials and Technology in Universities of Shandong, Linyi University, Linyi, 276005, PR China.
State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian, 116024, PR China.
Talanta. 2020 May 15;212:120760. doi: 10.1016/j.talanta.2020.120760. Epub 2020 Jan 18.
Time-gated luminescence (TGL) probes based on lanthanide complexes have appealed wide attention in the detection of biologically relevant analytes because of their inimitable photophysical properties. In this work, a TGL probe (TR-HOCl) based on intramolecular Förster resonance energy transfer (FRET) system for specific determination of hypochlorous acid (HOCl) was designed and synthesized, in which a rhodamine derivative (energy acceptor) was conjugated to a luminescent Tb complex (energy donor). After reacting with HOCl, the Tb emission of TR-HOCl at 540 nm declined while the rhodamine emission at 580 nm increased, which leaded to an increase of the TGL intensity ratio of rhodamine to Tb complex (I/I) up to ~9-fold. The dose-dependent increase of I/I gives a nice linearity in HOCl concentration range of 0.5-45 μM. The detection limit of for HOCl was determined to be 0.34 μM. Interestingly, the average luminescence lifetime of the Tb emission decreased (from 588 μs to 254 μs) accompanied with the FRET process and the value gave a fine linearity to the variation of HOCl concentration. Additionally, TR-HOCl showed great selectivity for recognition of HOCl over other ROS, RNS, biothiols and other interference. These properties endow TR-HOCl to be conveniently applied for high accurate recognition of HOCl with ratiometric TGL and luminescence lifetime dual-signal output. Finally, TR-HOCl was successfully applied for the TGL determination of HOCl in HepG2 cells. The co-localization experiments of TR-HOCl with LysoSensor Green revealed the lysosome-localizing property of the probe in live cells. The study demonstrated that TR-HOCl could be a competent tool for investigating roles of HOCl in various physiological processes.
基于镧系配合物的时间门控发光（TGL）探针因其独特的光物理性质而在检测生物相关分析物方面引起了广泛关注。在这项工作中，设计并合成了一种基于分子内Förster 共振能量转移（FRET）系统的 TGL 探针（TR-HOCl），用于特异性测定次氯酸（HOCl），其中将罗丹明衍生物（能量受体）与发光铽配合物（能量供体）连接。与 HOCl 反应后，TR-HOCl 在 540nm 处的 Tb 发射强度下降，而在 580nm 处的罗丹明发射强度增加，导致罗丹明与 Tb 配合物（I/I）的 TGL 强度比增加了~9 倍。I/I 的剂量依赖性增加在 0.5-45μM 的 HOCl 浓度范围内给出了良好的线性关系。HOCl 的检测限被确定为 0.34μM。有趣的是，Tb 发射的平均荧光寿命随着 FRET 过程而降低（从 588μs 降低到 254μs），并且该值与 HOCl 浓度的变化呈良好的线性关系。此外，TR-HOCl 对 HOCl 与其他 ROS、RNS、生物硫醇和其他干扰物的识别具有很好的选择性。这些特性使 TR-HOCl 能够方便地应用于具有比率 TGL 和荧光寿命双重信号输出的 HOCl 的高精确识别。最后，TR-HOCl 成功应用于 HepG2 细胞中 HOCl 的 TGL 测定。TR-HOCl 与 LysoSensor Green 的共定位实验揭示了探针在活细胞中的溶酶体定位性质。研究表明，TR-HOCl 可以成为研究 HOCl 在各种生理过程中作用的有力工具。
