A novel multi-purpose convenient Al3+ ion fluorescent probe based on phenolphthalein

•Synthesis of a fluorescent probe (FS) by Schiff base reaction using phenolphthalein and thiophene hydrazide.•After FS is combined with Al3+ ions, the effect of inhibiting photo-induced electron transfer is inhibited, and fluorescence emission is realized.•The stoichiometric ratio and binding constant of FS and Al3+ ions are 1:2, 5.6 × 105M−1, respectively.•The minimum detection limits of FS for Al3+ ions in DMSO and ethanol solvents are 27.5 and 18 nM, respectively.•FS fluorescent probes can be prepared into test papers for rapid on-site detection of Al3+ ions. In this paper, phenolphthalein and thiophene hydrazide are used as raw materials to design and synthesize a fluorescent probe (FS) that can selectively detect trace amounts of Al3+ ions in dimethyl sulfoxide and ethanol. After FS is combining with Al3+ ions, the photo induced electron transfer (PET) is inhibiting, so it emits strong blue fluorescence (453 nm) to realize the specific detection of Al3+ ions. Tested by Job's plot and Benesi–Hildebrand method, the binding ratio and binding constant of FS and Al3+ ion are 2:1 and 5.6 × 105 M−1, respectively. As shown by the fluorescence gradient concentration testing, the minimum detection limits of FS in DMSO and ethanol were 2.75 × 10−8 M and 1.8 × 10−8 M, respectively, both of which were lower than the WHO standard for Al3+ ions in drinking water (7.41 µM). FS fluorescent probes can be prepared as detection solvents and test strips for a wide range of applications in the detection of trace Al3+ ions.