Selective interactions of trivalent cations Fe3 +, Al3 + and Cr3 + turn on fluorescence in a naphthalimide based single molecular probe

• A new single molecular multi-analyte probe 1 for the selective detection of Fe3 +, Al3 + and Cr3 + ions is reported.
• Fe3 +, Al3 + and Cr3 + form a 1:1 complex with 1, inhibit the PET operating in 1, turn-on the fluorescence.
• Competing monovalent, divalent and other trivalent metal cations do not interfere with the detection process.
• Probe 1 is membrane permeable, non-lethal and useful for imaging intracellular Fe3 +, Al3 + or Cr3 + levels in live cells.

Synthesis and fluorescence turn-on behavior of a naphthalimide based probe is described. Selective interactions of trivalent cations Fe3 +, Al3 + or Cr3 + with probe 1 inhibit the PET operating in the probe, and thereby, permit the detection of these trivalent cations present in aqueous samples and live cells. Failure of other trivalent cations (Eu3 +, Gd3 + and Nb3 +) to inhibit the PET process in 1 demonstrates the role of chelating ring size vis-à-vis ionic radius in the selective recognition of specific metal ions.

Through selective interactions, the trivalent cations Fe3 +, Al3 + and Cr3 + turn on fluorescence by inhibiting PET operating in a naphthalimide based probe.Figure optionsDownload as PowerPoint slide