| abstract |
A fluorescent probe which is represented by the following formula (wherein R 1 and R 2 represent hydrogen atom, or a substituent for trapping proton, a metal ion, or an active oxygen species; R 3 represents a monovalent substituent other than hydrogen atom, carboxy group, or sulfo group; R 4 and R 5 represent hydrogen atom, a halogen atom, or an alkyl group; R 6 to R 9 represent an alkyl group; R 10 and R 11 represent hydrogen atom, a halogen atom, or an alkyl group; M − represents a counter ion; and the combination of R 1 , R 2 , and R 3 (1) imparts a substantially high electron density to the benzene ring to which they bond so that the compound can be substantially non-fluorescent before trapping proton, a metal ion, or an active oxygen species, and (2) substantially reduces electron density of the benzene ring to which they bond so that the compound after trapping proton, a metal ion, or an active oxygen species can be highly fluorescent after the trapping. |