Structurally simple azo based chromogenic R1 for the selective sensing of cyanide ion in aqueous medium

Palanisamy Kalpana; Sivalingam Suganya; Sivan Velmathi

doi:10.1016/j.saa.2016.07.045

Structurally simple azo based chromogenic R1 for the selective sensing of cyanide ion in aqueous medium

Spectrochim Acta A Mol Biomol Spectrosc. 2017 Jan 15:171:162-167. doi: 10.1016/j.saa.2016.07.045. Epub 2016 Aug 3.

Authors

Palanisamy Kalpana¹, Sivalingam Suganya¹, Sivan Velmathi²

Affiliations

¹ Organic and Polymer Synthesis Laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli, 620 015, India.
² Organic and Polymer Synthesis Laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli, 620 015, India. Electronic address: velmathis@nitt.edu.

PMID: 27526339
DOI: 10.1016/j.saa.2016.07.045

Abstract

Structurally simple azo linked Schiff base R1 was synthesized and characterized using IR, ¹H NMR and mass spectroscopic techniques. The selective sensing of cyanide anion over other anions such as fluoride, chloride, bromine, iodide, acetate, nitrate, hydrogen sulphate and dihydrogenphosphate was revealed by naked-eye color change and UV-vis spectra. Addition of CN^- ions to the R1 showed a dramatic change in color from pale yellow to intense yellow along with the formation of a new band at 415nm in the absorption spectrum even in 100% aqueous medium. The interaction between R1 and cyanide was also investigated using ¹H NMR titration study. The R1 showed limit of detection (LOD) up to micromolar level at 2.72×10^-6M. Job's plot reveals the existing binding mode of R1 and CN^- ion in molar ratio of 1:1 (R1:CN^-).

Keywords: Aqueous medium; Cyanide ion; Naked eye; Real samples; Schiff base.