Turn-on fluorogenic sensors based on an anthraquinone signaling unit for the detection of Zn(II) and Cd(II) ions

Turn-on fluorescent chemosensors based on an anthraquinone moiety, N,N'-(9,10-dioxo-9,10-dihydroanthracene-1,8-diyl)bis(2-(bis(pyridin-2-ylmethyl)amino)acetamide) (1) and N,N'-(9,10-dioxo-9,10dihydroanthracene-2,6-diyl)bis(2-(bis( pyridin-2-ylmethyl)amino)acetamide) (2), have been successfully synthesized with the overall yields of 61% and 90%, respectively. The structures of both chemosensors 1 and 2 were elucidated using several spectroscopic techniques such as 1H NMR, C-13 NMR, 2D-NMR, FTIR and HRMS. The target chemosensor 1 is a promising tool for the detection of trace levels of d(10) metal ions, such as Zn(II) and Cd(II) ions, by exhibiting a significant fluorescence enhancement via a turn-on photoinduced electron transfer (PET) mechanism with a rapid and highly reproducible signal, and low detection limit values of 0.408 mu M and 0.246 mu M, for Zn(II) and Cd(II), respectively.

Automated summary

Turn-on fluorescent chemosensors based on an anthraquinone moiety have been successfully synthesized and can detect trace levels of Zn(II) and Cd(II) ions by enhancing fluorescence through a turn-on photoinduced electron transfer mechanism.