Description:
AbstractWe designed a thiophene‐based fluorescent chemosensor DHTC ((E)‐2‐([3,5‐dichloro‐2‐hydroxybenzylidene]amino)thiophene‐3‐carboxamide) for detecting gallium (Ga3+). DHTC could probe Ga3+ using fluorescence enhancement. The limit of detection for Ga3+ by DHTC was 0.39 μM. The binding mode of DHTC to Ga3+ was determined as a 1:1 ratio from analysis by Job’s plot and electrospray ionization‐mass spectrometry (ESI‐MS). In addition, DHTC could selectively detect Ga3+ using test kits. The sensing process of Ga3+ by DHTC was presented using ultraviolet–visible light titration, Job’s plot, ESI‐MS, 1H nuclear magnetic resonance titration, and density functional theory calculation.