A Highly Selective Turn-on and Reversible Fluorescent Chemosensor for Al3+ Detection Based on Novel Salicylidene Schiff Base-Terminated PEG in Pure Aqueous Solution

The development of highly selective and sensitive chemosensors for Al3+ detection in pure aqueous solution is still a significant challenge. In this work, a novel water-soluble polymer PEGBAB based on salicylidene Schiff base has been designed and synthesized as a turn-on fluorescent chemosensor for the detection of Al3+ in 100% aqueous solution. PEGBAB exhibited high sensitivity and selectivity to Al3+ over other competitive metal ions with the detection limit as low as 4.05 × 10−9 M. PEGBAB displayed high selectivity to Al3+ in the pH range of 5–10. The fluorescence response of PEGBAB to Al3+ was reversible in the presence of ethylenediaminetetraacetic acid (EDTA). Based on the fluorescence response, an INHIBIT logic gate was constructed with Al3+ and EDTA as two inputs. Moreover, test strips based on PEGBAB were fabricated facilely for convenient on-site detection of Al3+.