A colorimetric and fluorescent chemosensor for copper ions in aqueous media and its application in living cells

Merocyanine dye 1 was prepared as an effective colorimetric and fluorescent chemosensor for copper ions in aqueous media, and displays a significant color change from reddish-purple to yellow with a large blue shift of 94 nm in its absorption spectrum in the presence of one equivalent of copper. As an on-off fluorescent sensor, it is feasible to detect copper ions in living cells due to its good cell permeability and high solubility under physiological conditions.