A novel highly sensitive and selective fluorescent sensor for imaging copper (II) in living cells

In this work, we designed and synthesized a novel quinolin-based derivative which exhibited signaling behaviors for Cu(2+). Upon the addition of Cu(2+) to the solution of the molecule, it displayed an obvious fluorescence quenching in a linear fashion due to the formation of a 1:1 metal-ligand complex. This fluorescent sensor exhibited a rare sensitivity toward Cu(II) (the level of magnitude could be 6 × 10(-8)), a rapid response (<10 s) and also high selectivity toward Cu(2+) over other metal ions such as Na(+), K(+), Ca(2+), Mg(2+), Ba(2+), Fe(3+), Mn(2+), Hg(2+), Pb(2+), Cd(2+), Cr(3+), Co(2+), Zn(2+) and Al(3+). Simultaneously, the cell imaging experiments and filter paper test demonstrated its extensive applicability.