A naphthylamide based fluorescent probe for detection of Al3+, Fe3+, and CN- with high sensitivity and selectivity

Neda Ahfad; Gholamhossein Mohammadnezhad; Soraia Meghdadi; Hossein Farrokhpour

doi:10.1016/j.saa.2019.117753

A naphthylamide based fluorescent probe for detection of Al³⁺, Fe³⁺, and CN^- with high sensitivity and selectivity

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Mar 5:228:117753. doi: 10.1016/j.saa.2019.117753. Epub 2019 Nov 6.

Authors

Neda Ahfad¹, Gholamhossein Mohammadnezhad², Soraia Meghdadi¹, Hossein Farrokhpour¹

Affiliations

¹ Department of Chemistry, Isfahan University of Technology, Isfahan 8415683111, Iran.
² Department of Chemistry, Isfahan University of Technology, Isfahan 8415683111, Iran. Electronic address: mohammadnezhad@cc.iut.ac.ir.

PMID: 31732474
DOI: 10.1016/j.saa.2019.117753

Abstract

A naphthylamide based fluorescent chemosensor, N,N'-(1,2-phenylene)bis(1-hydroxy-2-naphthamide) (H₄L), for detection of Fe³⁺ and Al³⁺ cations as well as CN^- anion is reported. This compound has been synthesized by a novel and facile synthetic method with high yield and characterized by FT-IR, ¹H NMR, elemental analysis, and UV-Vis spectroscopy. It could detect Fe³⁺ and Al³⁺ ions in different media with different excitation and emission wavelengths. In DMSO solution, H₄L showed selective ON-OFF quenching of its 451 nm emission in the presence of Fe³⁺. On the other hand, in DMF solution, H₄L exhibited selective OFF-ON fluorescence upon the addition of Al³⁺, the intensity at 429 nm increases drastically by 24-fold. Also, among the anions, the probe can selectively distinguish CN^- by deprotonation of OH and NH groups, as proved by ¹H NMR titration. TD-DFT calculation supports the UV-Vis and fluorescence measurements of the chemosensor.

Keywords: (1)H NMR titration; Fe(3+), Al(3+) and CN(−) sensor; Fluorescent chemosensor; Naphthylamide; TD-DFT.