title: Red fluorescent scaffold for highly sensitive protease activity probes.
abstract: We have developed a novel red fluorescent dye, 2Me SiR600 (λ(em)=613 nm), in which the O atom of Rhodamine Green at the 10 position of the xanthene moiety is replaced with a Si atom, as a scaffold for probes to detect protease activity with extremely high S/N ratio. As proof of concept, we designed and synthesized probes for caspase-3 activity (Z-DEVD-SiR600) and leucine aminopeptidase activity (Leu-SiR600). Caspase-3-mediated cleavage of Z-DEVD-SiR600 resulted in a large bathochromic shift (93 nm) of the absorption maximum and a 432-fold fluorescence enhancement.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Tokyo 113 0033, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Kushida
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Hanaoka
authors.forename: Toru
authors.initials: T
authors.lastname: Komatsu
authors.forename: Takuya
authors.initials: T
authors.lastname: Terai
authors.forename: Tasuku
authors.initials: T
authors.lastname: Ueno
authors.forename: Kengo
authors.initials: K
authors.lastname: Yoshida
authors.forename: Masanobu
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nagano
mesh_terms: D053148:Caspase 3 / Q000032:analysis*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D007931:Leucyl Aminopeptidase / Q000032:analysis*; D010100:Oxygen / Q000737:chemistry; D012235:Rhodamines / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity
chemical_list: D005456:Fluorescent Dyes; D012235:Rhodamines; D007931:Leucyl Aminopeptidase; D053148:Caspase 3; D010100:Oxygen; D012825:Silicon