Acrylonitrile Embedded Benzimidazole-Anthraquinone Based Chromofluorescent Sensor for Ratiometric Detection of CN − ions in Bovine Serum Albumin

Abstract A novel acrylonitrile embedded benzimidazole-based probe 3 has been designed and synthesized by conjugating anthraquinone with 2-(1H-benzo[d]imidazol-2-yl)acetonitrile. The probe 3 potentially detects CN − ions in H 2 O/CH 3 CN (1:9; v/v), solid state, and plasma-like solution via chromo and fluorometric approach. The probe 3 displayed an absorption redshift from 415 nm to 472 nm and emission redshift from 510 nm to 610 nm in the presence of CN − ions, in H 2 O/CH 3 CN (1:9; v/v). The probe 3 displayed colour change from yellow to orange along with red emission in the presence of CN − ions. The probe 3 showed very low detection limit of 37 × 10 −9  M. Furthermore, probe 3 is also utilized as a portable paper strip for on-site detection of CN − ions. The 1 H NMR and mass spectrometry analysis confirmed the nucleophilic addition of CN − ions to probe 3 .