A Selective Fluorescent Optode for Lead(II) Based on the Dansylamidopropyl Pendant Arm Derivative of 1,4-dioxa-7,13-dithia-10-azacyclopentadecane ([15]aneNS2O2)

Mojtaba Shamsipur

First

Conceptualization

;Moslem Mohammadi

Second

Investigation

;Massimiliano Arca

Member of the Collaboration Group

;Alessandra Garau

Member of the Collaboration Group

;Vito Lippolis

Penultimate

Conceptualization

;Ali Barati 1

Last

2023-01-01

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Abstract

In this study, a novel highly sensitive and selective fluorescent optodemembrane aimed at the determination of Pb(II) ion is proposed by incorporating N-(3-(1,4-dioxa-7,13-dithia-10-azacyclopentadecan- 10-yl)propyl)-5-(dimethylamino)naphthalene-1-sulfonamide (L) as fluoroionophore in polyvinyl chloride (PVC) containing 2-nitrophenyl octylether (NPOE) as a plasticizer. In addition to high stability and reproducibility, the proposed optosensor showed a unique selectivity toward Pb(II) ion, with a wide linear range of molar concentrations (1.0  10􀀀9–1.0  10􀀀3 M) and a low detection limit of 7.5  10􀀀10 M in solution at pH 5.0. The formation constants of the Pb(II) complexes with the fluoroionophore were evaluated by fitting the fluorescence data with a nonlinear least-squares curvefitting program, and further information about the structures of the complexes were evaluated based on hybrid-DFT calculations. The optosensor exhibited a fast response time of less than three min, being easily regenerated by exposure to a solution of dithiothreitol. The sensor was applied to the determination of Pb(II) in real samples (canned tuna fish), and it provided satisfactory results comparable to those obtained via atomic absorption spectrometry (AAS).