A cyanobiphenyl–based fluorescent ''lighting–up'' sensor for highly selective and sensitive recognition of Al 3+ : Theoretical, practical and bioimaging studies

The recognition of toxic Al 3+ in foods and biosystems has of great interest to researchers. Herein, a novel cyanobiphenyl–based chemosensor CATH (E)-N'-((4′-cyano-4-hydroxy-[1,1′-biphenyl]-3-yl)methylene)thiophene-2-carbohydrazide was fabricated and shown to recognize Al 3+ in HEPES buffer:EtOH (90:10, v:v, pH = 7.4) by ''lighting–up'' fluorescence sensing. The CATH evidenced high sensitivity (LOD = 13.1 nM) and excellent selectivity to Al 3+ over competing cations. The Job's plot, TOF–MS and theoretical computation studies were performed to probe the binding mechanism of Al 3+ to CATH. Additionally; CATH was successfully utilized to practical applications and employed to recover of Al 3+ from different food samples. More importantly, it was employed to intracellular Al 3+ detection in living cells including THLE2 and HepG2.