Reactive oxygen species (ROS) are mostly produced in the cellular mitochondria of various organs and tissues of living organisms via the incomplete reduction of molecular oxygen, which is greatly intensified under external stimulations and injuries. On the one hand, the highly active ROS play a key role in cell signaling, homeostasis, energy production and defense mechanism against infection to regulate a wide range of biological or pathological functions, but on the other hand the excessive generation of ROS may also cause cell ageing, DNA/protein mutations and various diseases.
Recently, Prof. ZHANG Zhongping’ s research group from Institute of Intelligent Machines (IIM), Chinese Academy of Sciences (CAS), made a significant progress by developing a single fluorescent probe to achieve the effective discrimination and profiling of hydroxyl radicals (•OH) and hypochlorous acid (HClO) in living organisms. The paper entitled “Real-Time Discrimination and Versatile Profiling of Spontaneous Reactive Oxygen Species in Living Organisms with a Single Fluorescent Probe” was published in the Journal of American Chemical Society (http://pubs.acs.org/doi/abs/10.1021/jacs.5b12848).
In this paper, the researchers reconstructed fluorescein through chemically grafting an additional five-membered heterocyclic ring and a lateral triethyleneglycol chain, which not only turned off the fluorescence of fluorescein, but also created the dual reactive sites to ROS and the penetration capability in passing through various biological barriers. The reactions of probe with •OH and HClO simultaneously resulted in cyan and green emissions, respectively, which provided real-time discrimination and quantitative analysis of the two ROS in cellular mitochondria. Surprisingly, researchers observed the accumulation of probes in the intestine and liver of a normal-state zebrafish and the transfer pathway from intestine-to- blood-to-organ-to-kidney-to-excretion clearly presented the profiling of spontaneous •OH and HClO in these metabolic organs. For the first time, the visualized observation of the stress generation of •OH at the fresh wound of zebrafish is realized, in spite of its extremely short lifetime. These successful/unique applications prospect that the versatile probe will be a powerful tool in the investigations of ROS in living systems.
A single Fluorescent Probe with dual reactive sites to ROS
Visualization of •OH released from the fresh wound of zebrafish
Visualizations of spontaneous ROS in normal zebrafish embryos
Prof. ZHANG Zhongping,
CAS Center for Excellence in Nanoscience,
Institute of Intelligent Machines,
Chinese Academy of Sciences, Hefei, Anhui 230031, China.
Tel.: +86-551-65591156; fax: +86-551-65591156
E-mail: zpzhang@iim.ac.cn
