title: An FITC-BODIPY FRET couple: application to selective, ratiometric detection and bioimaging of cysteine.
abstract: A novel FRET couple of fluorescein is disclosed, and it was readily constructed by conjugating an amino-BODIPY dye, a new FRET donor, with fluorescein isocyanate. Its potential was demonstrated by a fluorescence sensing system for cysteine, which was prepared by introducing acryloyl groups to the fluorescein moiety. The FRET probe exhibited promising ratiometric response to cysteine with high selectivity and sensitivity in a buffer solution containing acetonitrile at a physiological pH of 7.4, but showed slow reactivity. This slow response was solved by addition of a surfactant, thus allowing ratiometric imaging and determination of the endogenous level of cysteine in cells in HEPES buffer, by confocal fluorescence microscopy. Imaging experiments toward various cells suggested that such aryl acrylate type probes are vulnerable to the ubiquitous esterase activity. For the selected C6 cell line, in which the esterase activity was minimal, the ratiometric quantification of cysteine level was demonstrated. The FRET probe was also applied to determine the level of cysteine in human blood plasma.
authors.affiliation: Department of Chemistry and Center for Electro-Photo Behaviors in Advanced Molecular Systems, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang, 790-784 (Republic of Korea), Fax: (+82) 54-279-5877.
authors.forename: Dong Hee
authors.initials: DH
authors.lastname: Ma
authors.forename: Dokyoung
authors.initials: D
authors.lastname: Kim
authors.forename: Takuya
authors.initials: T
authors.lastname: Akisawa
authors.forename: Kyung-Ha
authors.initials: KH
authors.lastname: Lee
authors.forename: Kyong-Tai
authors.initials: KT
authors.lastname: Kim
authors.forename: Kyo Han
authors.initials: KH
authors.lastname: Ahn
mesh_terms: D000818:Animals; D001896:Boron Compounds / Q000737:chemistry*; D002460:Cell Line; D003545:Cysteine / Q000737:chemistry*; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D008823:Micelles
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; D008823:Micelles; D016650:Fluorescein-5-isothiocyanate; D003545:Cysteine
keywords: FRET; amino-bodipy; bioimaging; cysteine; fluorescence