Al3+ sensing through different turn-on emission signals vis-à-vis two different excitations: Applications in biological and environmental realms.

A rationally designed Schiff base chemosensor (L) could render specific detection of Al3+ ions with two distinct turn-on emission signals, separated by over 100 nm upon excitation at two different wavelengths. The utility of the probe lies in facilitating sensing in 80% aqueous medium with an emission close to 600 nm via an intramolecular charge transfer (ICT) mechanism. The biocompatible and cell permeable probe could readily sense Al3+ in live HeLa cells as well. The affinity of the probe for Al3+could be leveraged to specifically study DNA- Al3+ interaction in solution.