Wang Qiuyue, Ji Haiyang, Hao Yitong, Jia Dongli, Ma Hongyu, Song Changying, Qi Honglan, Li Zhao, Zhang Chengxiao
Shaanxi Engineering Laboratory for Food Green Processing and Safety Control, and Shaanxi Key Laboratory for Hazard Factors Assessment in Processing and Storage of Agricultural Products, College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an 710062, China.
Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
Anal Chem. 2024 Dec 24;96(51):20189-20196. doi: 10.1021/acs.analchem.4c03824. Epub 2024 Dec 13.
Hydroxyl radical (·OH), taken as the most active and aggressive reactive oxygen species (ROS), plays an important role in cell redox regulation and ferroptosis processes. It is a great challenge to develop methods for highly selective and sensitive detection and imaging of ·OH. A new near-infrared (NIR) fluorescence probe was designed and synthesized by introducing 3-methylpyrazolone as the specific recognition moiety to the hemicyanine backbone of the NIR fluorophore , which formed with the hydrazine group. exhibited excellent detection performance , such as instantaneous response, low detection limit of 24 nM, and excellent selectivity without the interference from other ROS. Based on the actions of ·OH promoter phenylmercuric acetate (PMA) and ·OH scavenger 4-hydroxy-TEMPO (Tempol), was successfully applied to obtain images of endogenous ·OH in HepG2 cells, , and mice. The results show that can stably and efficiently image endogenous ·OH, the fluorescence intensity of the experimental group incubated with PMA was higher than that of the control group incubated with only, and a significant decrease could be observed in the inhibitor group incubated with Tempol. More importantly, can achieve the detection of endogenous ·OH in HepG2 cells during ferroptosis by using erastin and deferoxamine mesylate (DFO) to induce or inhibit ferroptosis, revealing that the fluorescence intensity change of was caused by ·OH generated and ferroptosis is accompanied by significant ·OH generation. The excellent performance of makes it a promising candidate for exploring the physiological and pathological processes associated with ferroptosis.
羟基自由基（·OH）作为活性最强、攻击性最强的活性氧物种（ROS），在细胞氧化还原调节和铁死亡过程中发挥着重要作用。开发用于·OH高选择性和灵敏检测及成像的方法是一项巨大挑战。通过将3-甲基吡唑啉酮作为特异性识别基团引入近红外（NIR）荧光团的半菁骨架中，并与肼基形成，设计并合成了一种新型近红外荧光探针。该探针表现出优异的检测性能，如即时响应、24 nM的低检测限以及出色的选择性，不受其他ROS的干扰。基于·OH促进剂乙酸苯汞（PMA）和·OH清除剂4-羟基-TEMPO（Tempol）的作用，该探针成功应用于获得HepG2细胞、组织和小鼠内源性·OH的图像。结果表明，该探针能够稳定、高效地对内源性·OH进行成像，用PMA孵育的实验组荧光强度高于仅用溶剂孵育的对照组，而用Tempol孵育的抑制剂组荧光强度显著降低。更重要的是，通过使用erastin和甲磺酸去铁胺（DFO）诱导或抑制铁死亡，该探针能够实现对HepG2细胞铁死亡过程中内源性·OH的检测，揭示了该探针荧光强度的变化是由产生的·OH引起的，并且铁死亡伴随着显著的·OH生成。该探针的优异性能使其成为探索与铁死亡相关的生理和病理过程的有前途的候选者。
