Recent Progress of Glutathione (GSH) Specific Fluorescent Probes: Molecular Design, Photophysical Property, Recognition Mechanism and Bioimaging

The selective detection of glutathione (GSH)in vitroandin vivohas attracted great attentions, credited to its important role in life activities and association with a series of diseases. Among all kinds of analytical techniques, the fluorescent probe for GSH detection become prevalent recently because of its ease of operation, high temporal-spatial resolution, visualization and noninvasiveness, etc. The special structural features of GSH, such as the nucleophilicity of sulfhydryl group, the concerted reaction ability of amino group, the negative charged nature, the latent hydrogen bonding ability along with its flexible molecular chain, are all potent factors to be employed to design the specific fluorescent probe for GSH and discriminate it from other bio-species including its analogues cysteine (Cys) and homocysteine (Hcy). This paper reviewed the studies in the last 3 years and was organized based on the reaction mechanism of each probe. According to the reactivity of GSH, various recognition mechanisms including Michael addition, nucleophilic aromatic substitution, ordinary nucleophilic substitution, multi-site reaction, and other unique reactions have been utilized to construct the GSH specific fluorescent probes, and the molecular design strategy, photophysical property, recognition mechanism, and bioimaging application of each reported probe were all discussed here systematically. Great progress has been made in this area, and we believe the analyses and summarization of these excellent studies would provide valuable message and inspiration to researchers to advance the research toward clinic applications.

Automated summary

Selective detection of glutathione (GSH) in vitro and in vivo has gained significant attention due to its role in life activities and diseases. Recent research has focused on using fluorescent probes for GSH detection, which offer advantages such as ease of use, high temporal-spatial resolution, visualization, and noninvasiveness. The unique structural features of GSH, such as the nucleophilicity of sulfhydryl group and negative charged nature, have been utilized to design specific fluorescent probes for GSH. Different recognition mechanisms have been employed, including Michael addition, nucleophilic aromatic substitution, ordinary nucleophilic substitution, multi-site reaction, and other unique reactions. This paper reviews the studies in the last 3 years based on the reaction mechanism of each probe. It discusses the molecular design strategy, photophysical property, recognition mechanism, and bioimaging application of each reported probe. The progress in this area is significant and the analysis and summarization of these studies provide valuable insights and inspiration for researchers working towards clinical applications.