A simple hydrazone as a fluorescent turn-on multianalyte (Al3+, Mg2+, Zn2+) sensor with different emission color in DMSO and resultant Al3+ complex as a turn-off sensor for F− in aqueous solution

A novel pyrazine hydrazone 1 has been designed and synthesized, which acts as a multiprobe for selective detection of Al3+, Mg2+, and Zn2+ in DMSO solution based on fluorescent enhancement with three different emission colors. The higher affinity of 1 toward Al3+ and Zn2+ compared with Mg2+ facilitates the establishment of a simple ratiometric fluorescent method for the detection of Al3+ and Zn2+ based on the 1 + Mg2+ system. Conversely, probe 1 selectively recognized Al3+ in DMSO-H2O cosolvent with a turn-on response, and the resultant 1 + Al3+ complex could determine F− via a fluorescence quenching signal. In addition, the probe is applied for imaging of Al3+ and F− in living cells.