A Simple Schiff Base as Fluorescent Probe for Detection of Al3+ in Aqueous Media and its Application in Cells Imaging

A novel fluorescence probe for the detection of Al 3+ was developed based on methionine protected gold nanoclusters (Met-AuNCs). A fluorescent Schiff base (an aldimine) is formed between the aldehyde group of salicylaldehyde (SA) and the amino groups of Met on the AuNCs, and developed for selective detection of Al 3+ in aqueous solution. Al 3+ can strongly bind with the Schiff base ligands, accompanied by the blue-shift and an obvious fluorescence emission enhancement at 455 nm. The limits of detection (LODs) of the probe are 2 pmol L −1 for Al 3+ . Moreover, the probe can successfully be used in fluorescence imaging of Al 3+ in living cells (SHSY5Y cells), suggesting that the simple fluorescent probe has great potential use in biological imaging.