Selective fluorescence sensor for Al3+ and Pb2+ in physiological condition by a benzene based tripodal receptor

We have synthesized a benzene based tripodal receptor containing naphthalene motifs as signaling unit. The receptor can selectively bind Al3+/Pb2+ metal ions with a significant change in its fluorescence and UV/Vis spectra, while the addition of other metal ions (Na+, K+, Ca2+, Mg2+, Cr3+, Hg2, Cu2+, Zn2+, Fe2+, Co2+, Ni2+, Cd2+, and Ag+) produces insignificant or minor changes. The formation of receptor-metal ion complex is also proved by NMR and mass spectroscopic analysis.