title: Phosphine quenching of cyanine dyes as a versatile tool for fluorescence microscopy.
abstract: We report that the cyanine dye Cy5 and several of its structural relatives are reversibly quenched by the phosphine tris(2-carboxyethyl)phosphine (TCEP). Using Cy5 as a model, we show that the quenching reaction occurs by 1,4-addition of the phosphine to the polymethine bridge of Cy5 to form a covalent adduct. Illumination with UV light dissociates the adduct and returns the dye to the fluorescent state. We demonstrate that TCEP quenching can be used for super-resolution imaging as well as for other applications, such as differentiating between molecules inside and outside the cell.
authors: Howard Hughes Medical Institute, and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Joshua C
authors: JC
authors: Vaughan
authors: Graham T
authors: GT
authors: Dempsey
authors: Eileen
authors: E
authors: Sun
authors: Xiaowei
authors: X
authors: Zhuang
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000737:chemistry* / Q000493:pharmacokinetics; D002460:Cell Line; D006801:Humans; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D010720:Phosphines / Q000737:chemistry* / Q000493:pharmacokinetics; D013696:Temperature
chemical_list: D002232:Carbocyanines; D010720:Phosphines; C085321:cyanine dye 5; C080938:tris(2-carboxyethyl)phosphine