Off-On-Off fluorescence behavior of an intramolecular charge transfer probe toward anions and CO2.
The photophysical behavior of a newly developed fluorescent probe, tricyanoethylphenyl phenanthroimidazole (TCPPI) has been studied. Upon interaction of different class of anions TCPPI displayed naked-eye sensitive fluorescence "turn-on" response to detect selectively F(-) (0.98μM, 18.62ppb) and CN(-) (1.12μM, 29.12ppb) anions in acetonitrile (MeCN). Job's plot analysis revealed a 1:1 binding stoichiometry between probe and anions. The spectral data analysis and 1H NMR titration studies suggested about the affinity of F(-) and CN(-) anions with moderately acidic -NH fragment of imidazolyl unit of probe through deprotonation and H-bonding interaction. Moreover, the anion activated probe upon interaction with CO2 revived photophysical properties of probe, "On-Off-On" type fluorescence and enabled anion-induced CO2 sensing in the medium.
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, UP, India.
Rashid
R
Ali
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, UP, India.
Syed S
SS
Razi
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, UP, India.
Mohammad
M
Shahid
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, UP, India.
Priyanka
P
Srivastava
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221 005, UP, India. Electronic address: arvindmisra2003@yahoo.com.
Arvind
A
Misra
CN(−) and CO(2); F(−); ICT; TCPPI