title: A fluorescence turn-on probe for cysteine and homocysteine based on thiol-triggered benzothiazolidine ring formation.
abstract: We synthesized a new coumarin-based probe TP, containing a disulfide moiety, to detect biothiols in cells. A fluorescence turn-on response is induced by the thiol-disulfide exchange of the probe, with subsequent intramolecular benzothiazolidine ring formation giving rise to a fluorescent product. The probe exhibits an excellent selectivity for cysteine (Cys) and homocysteine (Hcy) over glutathione (GSH) and other amino acids. The fluorescent probe also exhibits a highly sensitive fluorescence turn-on response to Cys and Hcy with detection limits of 0.8 μM for Cys and 0.5 μM for Hcy. In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the probe TP could be an efficient fluorescent detector for thiols in living cells.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC.
authors.forename: Shi-Rong
authors.initials: SR
authors.lastname: Liu
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC.
authors.forename: Chao-Yiu
authors.initials: CY
authors.lastname: Chang
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC. Electronic address: spwu@mail.nctu.edu.tw.
authors.forename: Shu-Pao
authors.initials: SP
authors.lastname: Wu
mesh_terms: D000818:Animals; D002460:Cell Line; D003545:Cysteine / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006710:Homocysteine / Q000032:analysis*; D057230:Limit of Detection; D051379:Mice; D008856:Microscopy, Fluorescence; D061848:Optical Imaging; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D053778:Thiazolidines / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D013438:Sulfhydryl Compounds; D053778:Thiazolidines; D006710:Homocysteine; D003545:Cysteine
keywords: Bioimaging; Coumarin; Cysteine; Fluorescent probe; Homocysteine