Synthesis of new colori/fluorimetric chemosensor for selective sensing of biologically important Fe3+, Cu2+ and Zn2+ metal ions

• Colori/fluorimetric sensing of multiple metal ions.
• Position and functionality dependent fluorescence sensing.
• Substitutional group dependent selectivity.
• Colorimetric sensing of Fe3+ and Cu2+ and fluorescence sensing of Zn2+.
• Structure–property studies.

New Schiff base chemosensors (1 and 2) based on aryl ether amine were synthesized and demonstrated positional isomer and functional group dependent colori/fluorimetric sensing of Fe3+, Cu2+ and Zn2+ at ppm level. Methoxy salicylaldehyde based chemosensor 1 exhibited selective colorimetric sensing of Fe3+ whereas 2-hydroxy naphthaldehyde based chemosensor 2 showed selective disappearance of yellow color for Cu2+ ions. Interestingly, both 1 and 2 exhibited a highly selective strong turn-on fluorescence for Zn2+. The significance of COOH group in 1 and 2 for Zn2+ turn-on fluorescence sensing has been confirmed by structure–property studies. Concentration dependent studies of 1 and 2 indicate that Fe3+, Cu2+ and Zn2+ can be detected up to 10 μM. The formation of 1:1 Zn2+ and chemosensor (1 and 2) confirmed by NMR studies. High selectivity of 1 and 2 was demonstrated by interference studies in presence of different metal ions.

New Schiff base chemosensors based on aryl ether amine were synthesized and demonstrated selective colorimetric as well as fluorescence sensing of biologically important Fe3+, Cu2+ and Zn2+ ions up to ppm level.Figure optionsDownload as PowerPoint slide