Anion-binding-induced and reduced fluorescence emission (ABIFE & ABRFE): A fluorescent chemo sensor for selective turn-on/off detection of cyanide and fluoride

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2021-01, Vol.245, p.118943, Article 118943
• Main Authors: Murugesan, Kumaresan, Jeyasingh, Vanthana, Lakshminarayanan, Sudha, Selvapalam, Narayanan, Dass, Geetha, Piramuthu, Lakshminarayanan
• Format: Article
• Language: English
• Subjects: Anion displacement assay; Anion receptors; Anion·π interactions; Colorimetric sensor
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2020.118943

A new hydrazine based π-hole assisted, electron deficient turn-on/off fluorescent and colorimetric sensor L with anion-binding induced/reduced fluorescent emission (ABIFE & ABRFE) has been designed and synthesized. The prepared sensor L exhibited excellent turn-on fluorescence emission in the presence of cyanide ion through ABIFE. On the other hand, the receptor L turns-off its fluorescence intensity upon binding with fluoride; however, the reduced emission intensity of this complex of L is recovered by addition of cyanide. The sensor L is almost intact with other tested anions. To the best of our knowledge, this is the first report on sensing of cyanide and fluoride by a neutral hydrazine based receptor via anion-binding-induced fluorescence emission (ABIFE) and anion-binding-reduced fluorescence emission (ABRFE) mechanisms respectively. The observed ABIFE and ABRFE phenomena of L with cyanide is further supported by UV–Vis, Emission, 1H NMR and IR spectroscopic studies. A new hydrazine based π-hole assisted; electron deficient turn-on/off fluorescent and colorimetric sensor L with anion-binding induced/reduced fluorescent emission (ABIFE & ABIFE) has been designed and synthesized. The prepared sensor L exhibited excellent turn-on fluorescence emission in the presence of cyanide ion through ABIFE. On the other hand, the receptor L turns-off its fluorescence intensity upon binding with fluoride; however, the reduced emission intensity of this complex of L is recovered by addition of cyanide. The sensor L is almost intact with other tested anions. To the best of our knowledge, this is the first report on sensing of cyanide and fluoride by a neutral hydrazine based receptor via anion-binding-induced fluorescence emission (ABIFE) and anion-binding-reduced fluorescence emission (ABRFE) mechanisms respectively. The observed ABIFE and ABRFE phenomena of L with cyanide is further supported by UV–Vis, Emission, 1H NMR and IR spectroscopic studies. [Display omitted] •A new hydrazine based π-hole assisted, electron deficient turn-on/off fluorescent and colorimetric sensor L with anion-binding induced/reduced fluorescent emission (ABIFE & ABRFE) has been designed and synthesized.•The prepared sensor L exhibited excellent turn-on fluorescence emission in the presence of cyanide ion through ABIFE. On the other hand, the receptor L turns-off its fluorescence intensity upon binding with fluoride.•The sensor L is almost intact with other tested anions. To the best of our