Salicylimine-Based Fluorescent Chemosensor for Aluminum Ions and Application to Bioimaging

In this study, an assay to quantify the presence of aluminum ions using a salicylimine-based receptor was developed utilizing turn-on fluorescence enhancement. Upon treatment with aluminum ions, the fluorescence of the sensor was enhanced at 510 nm due to formation of a 1:1 complex between the chemosensor and the aluminum ions at room temperature. As the concentration of Al3+ was increased, the fluorescence gradually increased. Other metal ions, such as Na+, Ag+, K+, Ca2+, Mg2+, Hg2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+, Cr3+, Fe3+, and In3+, had no such significant effect on the fluorescence. In addition, we show that the probe could be used to map intracellular Al3+ distribution in live cells by confocal microscopy.