Highly selective imidazole-appended 9,10-N,N′-diaminomethylanthracene fluorescent probe for switch-on Zn2+ detection and switch-off H2PO4− and CN− detection in 80% aqueous DMSO, and applications to sequential logic gate operations

• Published in: Sensors and actuators. B, Chemical Chemical, 2017-08, Vol.247, p.840-849
• Main Authors: Pandith, Anup, Uddin, Nizam, Choi, Cheol Ho, Kim, Hong-Seok
• Format: Article
• Language: English
• Subjects: CN; H2PO4; Imidazole; Logic gates; Sequential detection; Zn2+-ensemble
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.03.112

[Display omitted] •Imidazole-appended anthracene probe P for sensing Zn2+ was synthesized.•Zn2+ ions “switched on” the emission of P in 80% aqueous DMSO.•In situ generated P-Zn2+ (1:1) ensemble detected H2PO4− and CN− ions sequentially through “switch off” response in the absence and presence of Ca2+ ions respectively.•Sensing ability of P towards Zn2+ is attributed to PET and CHEF upon complexation.•Application of P to real water samples and sequential logic gate operations were demonstrated. A new imidazole-appended anthracene-based photoinduced electron transfer (PET) probe (P) was designed and synthesized. Probe P detected Zn2+ selectively in an 80% aqueous solution of dimethyl sulfoxide (DMSO) through a switch-on response at pH 7.5 without any interference from other metal ions. Probe P exhibited a moderately strong association constant (Ka) of 1.41×105M−1 and associated with Zn2+ ions with 1:1 stoichiometry. The in situ-generated P•Zn2+ (1:1) ensemble detected H2PO4− and CN− ions sequentially through switch-off responses. The selective discrimination of H2PO4− and CN− ions occurred both in the absence and presence of Ca2+ ions at pH 7.5 in a N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid (HEPES) buffer. The switch-on response was driven by the selective complexation of P with Zn2+ ions, mediated by the combined effects of PET and chelation-induced enhanced fluorescence, resulting in a more structurally rigid complex. Applications of P to real water sample analysis and sequential logic gate operations were demonstrated. The lowest detection limits for Zn2+, H2PO4−, and CN− ions in 80% aqueous DMSO were determined to be 1.0×10−9, 1.0×10−9, and 8.0×10−9M, respectively.