A selective turn-on fluorescent probe for Al3+ based-on a diacylhydrazone deritive in aqueous medium and its cell imaging

Al3+ has no spectroscopic characteristics and its coordination ability is very poor. Therefore, the detection of Al3+ is a challenging task. To address this issue, here we report a diacylhydrazone-based fluorescent chemosensor (L) for Al3+ structurally characterized by HRMS and NMR spectroscopy. The selective test revealed that L had a high selectivity towards Al3+ with a turn-on response in DMF/H2O (v/v, 8: 2) buffer solution. The combination ratio between L and Al3+ was determined to be 1:2 as supported by Job's plot analysis and NMR titration experiment. The recognition of Al3+ was without interference of other competing species. The detection limit was calculated to be as low as 2.41 mu M. Moreover, the probe was proved to be of low cytotoxicity in physiological condition and it was applied to image Al3+ in living cells successfully.