A turn-on fluorescent chemosensor for Cu~(2+) in aqueous media and its application to bioimaging

摘要

A rhodamine-based fluorogenic probe bearing the quinaldine unit (L1) was developed as a turn-on fluorescent chemosensor for Cu~(2+). Upon binding with Cu~(2+), comparable amplifications of absorption and fluorescence signals were observed, which suggest that chemosener L1 effectively avoided the fluorescence quenching caused by the paramagnetic nature of Cu~(2+). Importantly, L1 can selectively respond to Cu~(2+) over other commonly coexistent metal ions (such as K, Ca~(2+), Mg~(2+), Ni~(2+), Co~(2+), Mn~(2+), Fe~(2+), Fe~(3+), Hg~(2+), Zn~(2+), Cr~(3+)) in aqueous media with a rapid response time (<2 min). In addition, biological imaging studies using living cells to monitor Cu~(2+) is successfully demonstrated.