Electroanalytical and spectral investigation of organic receptors as colorimetric and absorption ratiometric anion chemosensor. Issue 2 (1st February 2018)

• Record Type: Journal Article
• Authors: Pangannaya, Srikala; Thimaradka, Vikram; Trivedi, Darshak R.
• Is Part Of: Supramolecular chemistry. Volume 30:Issue 2(2018)
• Page Start: 103
• Page End: 114
• Publication Date: 2018-02-01
• Subjects: Colorimetric -- electroanalytical -- ratiometric -- tautomerism -- chemosensor; Macromolecules -- Periodicals; Supramolecular chemistry -- Periodicals; 547.005
• DOI: 10.1080/10610278.2017.1363392
• Languages: English
• ISSNs: 1061-0278

Abstract

Abstract: Colorimetric receptorsR1 andR2 have been designed and synthesized by Schiff base condensation and characterised by standard spectroscopic techniques. Anion binding ability of the receptors have been investigated quantitatively through optical, electrochemical and 1 HNMR titration studies. UV-vis spectra of receptorR1 andR2 exhibited a significant red shift for F − and AcO − ions with a visual color response. ReceptorR1 exhibited selective response towards AcO − ion in the presence of HEPES buffer media. Incremental color change of receptorR2 with the higher equivalence of AcO − ions clearly represent the ratiometric response. Cyclic voltammetric studies ofR1 andR2 exhibits shift in oxidation and reduction peak with successive addition of AcO − ions indicating the anion induced oxidation of -NH and reduction of the keto group and nitro species. Electrooptical and 1 H NMR titration studies ofR2 collectively reflects the anion induced change of chromophore from C=N to N=N indicative of azo-hydrazone tautomeric signaling in the presence of AcO − ions. Lower detection limit of 2.1 and 0.41 ppm achieved with sodium salt of AcO − ion withR1 andR2 reflects their utility as colorimetric chemosensor. Abstract :