%A Sonakshi Sasan %A Tavishi Chopra %A Annah Gupta %A Dolma Tsering %A Kamal K Kapoor %A Raman Parkesh %O The copyright of this article belongs to ACS Publications %J ACS Omega %T Fluorescence ?Turn-Off? and Colorimetric Sensor for Fe2+, Fe3+, and Cu2+ Ions Based on a 2,5,7-Triarylimidazopyridine Scaffold %X Two cyanoimidazopyridine-based sensors (SS1 and SS2) were explored for the colorimetric and fluorometric detection of Fe2+, Fe3+, and Cu2+ ions in the semi-aqueous medium. The ?turn-off? fluorescence response of both sensors to these ions was due to the restriction in internal charge transfer. Job?s plot and semi-empirical calculations revealed that SS1 and SS2 complexed with Cu2+ ions in a 1:1 ratio and Fe2+/3+ ions in a 2:1 ratio, respectively. The sensors were found to have high binding constant (Ka) values and low detection limit values. FMO analysis using the semi-empirical quantum mechanics method revealed the decrease in energy gap after complexation with metal ions. Sensor-coated filter paper strips were prepared and analyzed, where the color changes in the strips could be utilized for the real-time detection of Fe2+, Fe3+, and Cu2+ ions. %N 13 %P 11114-11125 %V 7 %D 2022 %I ACS Publications %L open2994