title: Constructing a fluorescent probe for specific detection of cysteine over homocysteine and glutathione based on a novel cysteine-binding group but-3-yn-2-one.
abstract: A but-3-yn-2-one-based 7-diethylaminocoumarin dye was exploited as a fluorescent probe to specifically detect Cys over Hcy/GSH in pure PBS buffer. The probe itself is nonfluorescent due to the donor-excited photoinduced electron transfer (d-PET) process. The Cys-induced Michael addition-rearrangement cascade reaction leads to an amino-substituted product with strong fluorescence due to inhibiting C[double bond, length as m-dash]C isomerization induced fluorescence quenching by a produced intramolecular N-HO hydrogen bond. The Hcy (or GSH)-induced Michael addition reaction leads to a thiol-substituted product (or ), which lacks any intramolecular hydrogen-bonding interaction, and thus displays very poor fluorescence due to the efficient C[double bond, length as m-dash]C isomerization induced fluorescence quenching. Even in the presence of Hcy (or GSH), the probe could also detect Cys with the obvious fluorescence enhancement. Assisted by using a laser scanning confocal microscope, we demonstrated that the probe could selectively image Cys in the human renal cell carcinoma 786-0 cells.
authors: School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China. guow@sxu.edu.cn.
authors: Yawei
authors: Y
authors: Liu
authors: Song
authors: S
authors: Zhang
authors: Xin
authors: X
authors: Lv
authors: Yuan-Qiang
authors: YQ
authors: Sun
authors: Jing
authors: J
authors: Liu
authors: Wei
authors: W
authors: Guo
mesh_terms: D002292:Carcinoma, Renal Cell / Q000473:pathology; D045744:Cell Line, Tumor; D003374:Coumarins / Q000737:chemistry*; D003545:Cysteine / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D005978:Glutathione / Q000032:analysis; D006710:Homocysteine / Q000032:analysis; D006801:Humans; D018613:Microscopy, Confocal; D061848:Optical Imaging; D013050:Spectrometry, Fluorescence
chemical_list: D003374:Coumarins; D005456:Fluorescent Dyes; D006710:Homocysteine; D005978:Glutathione; D003545:Cysteine