A novel ferrocenyl-naphthalimide as a multichannel probe for the detection of Cu(ii) and Hg(ii) in aqueous media and living cells.

A novel ferrocenyl-naphthalimide multichannel probe 1 was designed and synthesized using a facile method. The color of the solution containing probe 1 changed from yellow to colorless upon the addition of Cu or Hg. Interestingly, probe 1 exhibited highly selective fluorescent turn-on for Cu and turn-off for Hg in aqueous solution. Probe 1 was an electrochemical Cu and Hg ion sensor, in which the Fc/Fc redox couple was significantly shifted (ΔE = 178 mV and ΔE = 53 mV, respectively) upon complexation. Therefore, probe 1 can act as a naked-eye chemosensor, as well as an electrochemical and a fluorescent probe for Cu and Hg. Furthermore, this is the first reported probe that can be used for the bifunctional fluorescent detection of intracellular Cu and Hg by fluorescent imaging studies. These characteristics give this probe considerable potential in the study and analysis of Cu and Hg in complex biosystems.