Boronic Acid-linked Fluorescent And Colorimetric Probes For Copper Ions

摘要

The first examples of boronic acid-linked fluorescent and colorimetric chemosensors for copper ions are reported; the monoboronic acid-conjugated rhodamine probe displays a highly selective fluorescent enhancement with Cu~(2+) among the various metal ions whereas the fluorescence of the bisboronic acid-conjugated fluorescein probe is selectively quenched by Cu~(2+), probably by way of a PET mechanism.rnMetal-selective fluorescent chemosensors serve as useful tools for detection of cellular metal ions and thus have been widely exploited to detect biologically relevant metal ions in cells and/or organisms. Among the various transition metal ions, the copper ion plays a critical role as a catalytic cofactor for a variety of metalloenzymes, including superoxide dismutase, cytochrome c oxidase and tyrosinase. However, under overloading conditions, copper exhibits toxicity in that it causes neurodegenerative diseases, probably by its involvement in the production of reactive oxygen species. In this regard, fluorescent probes for copper ions have been extensively explored owing to the biological significance of these metal ions.