title: Selective Fluorescence Detection of Cysteine over Homocysteine and Glutathione Based on a Cysteine-Triggered Dual Michael Addition/Retro-aza-aldol Cascade Reaction.
abstract: In this work, a cysteine (Cys)-triggered dual Michael addition/retro-aza-aldol cascade reaction has been exploited and utilized to construct a fluorescent probe for Cys for the first time. The resulting fluorescent probe 8-alkynylBodipy 1 contains an activated alkynyl unit as Michael receptor and a Bodipy dye as fluorescence reporter and can highly selectively detect Cys over homocysteine (Hcy)/glutathione (GSH) as well as other amino acids with a significant fluorescence off-on response (∼4500-fold) and an ultralow detection limit (0.38 nM). The high selectivity of 1 for Cys could be attributed to a kinetically favored five-membered cyclic intermediate produced by the dual Michael addition of Cys with the activated alkynyl unit of 1. The big fluorescence off-on response is due to the subsequent retro-aza-aldol reaction of the five-membered cyclic intermediate that results in the release of a highly fluorescent 8-methylBodipy dye 2. The probe has been successfully used to detect and image Cys in serum and cells, respectively.
authors.affiliation: School of Chemistry and Chemical Engineering and ‡Institute of Biotechnology, Shanxi University , Taiyuan, Shanxi 030006, China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering and ‡Institute of Biotechnology, Shanxi University , Taiyuan, Shanxi 030006, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Lv
authors.affiliation: School of Chemistry and Chemical Engineering and ‡Institute of Biotechnology, Shanxi University , Taiyuan, Shanxi 030006, China.
authors.forename: Min
authors.initials: M
authors.lastname: Hou
authors.affiliation: School of Chemistry and Chemical Engineering and ‡Institute of Biotechnology, Shanxi University , Taiyuan, Shanxi 030006, China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Shi
authors.affiliation: School of Chemistry and Chemical Engineering and ‡Institute of Biotechnology, Shanxi University , Taiyuan, Shanxi 030006, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D003545:Cysteine / Q000032:analysis* / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000032:analysis* / Q000138:chemical synthesis / Q000737:chemistry; D005978:Glutathione / Q000737:chemistry*; D006367:HeLa Cells; D006710:Homocysteine / Q000737:chemistry*; D006801:Humans; D015394:Molecular Structure; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D000447:Aldehydes; D005456:Fluorescent Dyes; D006710:Homocysteine; C116609:3-hydroxybutanal; D005978:Glutathione; D003545:Cysteine