3 research outputs found
An efficient naphthalimide based receptor for selective detection of Hg2+and Pb2+ions Â
Naphthalimide based receptor 1 with N-substituted benzothiazole and pyrrolidine subunit is designed, synthesized, and characterized using FT-IR,1H and 13C NMR spectroscopy and mass spectrometry techniques. The receptor 1 exhibits prominent optical response for Hg2+and Pb2+ions allowing the detection of these ions in acetonitrile (ACN). The formation of the receptor 1:cation complexes have been investigated using UV-Vis and fluorescence emission titration. Further, the selectivity of the receptor 1towards Hg2+and Pb2+ ions on the presence of various interfering cations such as Mg2+, Ba2+, Ni2+, Co2+, Cu2+, Ag2+, Fe2+, Fe3+and Cr3+ has been confirmed by UV-Vis and fluorescence spectroscopy. The binding constant between receptor 1 and Hg2+ and Pb2+ was estimated by Benesi-Hildebrand plot and equations. The binding constants have been found to be Ka= 3.43286 ´ 10â6 and Ka= 2.84079 ´ 10â6 M for Hg2+ and Pb2+, respectively. The limit of detection (LOD) for Hg2+and Pb2+by receptor 1are down to 7.44 ´ 10â10 M and 1.26 ´ 10â9 M, respectively. In addition, Jobâs plot analysis reveals 1:2 binding stoichiometry between the receptor 1 and Pb2+ and Hg2+ cations.
A Naphthalimide-Benzothiazole Conjugate as Colorimetric and Fluorescent Sensor for Selective Trinitrophenol Detection
Although chemical structural modification of naphthalimides is widely employed for the purpose of sensing explosives, the effects of such modification have been little explored. Herein, we report the design and synthesis of a new naphthalimide-benzothiazole conjugate (1) and its ability to sense various nitrophenols by means of its colorimetric and fluorescent characteristics. Under long-range UV light (365 nm), 1 displayed a color change of its solution from bluish to colorless only upon addition of 2,4,6-trinitrophenol (TNP). Photoluminescence spectroscopy showed quantitative fluorescence quenching by TNP of the emission peaks of 1 at 398 nm and 418 nm due to donorâacceptor electron transfer. The interaction of 1 with TNP was via a cooperative, non-covalent hydrogen-bonding interaction. Receptor 1 exhibited high sensitivity and selectivity towards TNP over various aromatic nitro analytes. The binding constant (K) and SternâVolmer constant (Ksv) between 1 and TNP were found to be 5.332 Ă 10â5 M and 2.271 Ă 106 Mâ1, respectively. Furthermore, the limit of detection was calculated and found to be as low as 1.613 Ă 10â10 M
An efficient naphthalimide based receptor for selective detection of Hg<sup>2+</sup>and Pb<sup>2+</sup>ions <sup>#</sup>
1353-1361Naphthalimide based receptor 1 with N-substituted benzothiazole and pyrrolidine subunit is designed, synthesized, and
characterized using FT-IR,1H and 13C NMR spectroscopy and mass spectrometry techniques. The receptor 1 exhibits
prominent optical response for Hg2+and Pb2+ions allowing the detection of these ions in acetonitrile (ACN). The formation
of the receptor 1:cation complexes have been investigated using UV-Vis and fluorescence emission titration. Further, the
selectivity of the receptor 1towards Hg2+and Pb2+ ions on the presence of various interfering cations such as Mg2+, Ba2+,
Ni2+, Co2+, Cu2+, Ag2+, Fe2+, Fe3+and Cr3+ has been confirmed by UV-Vis and fluorescence spectroscopy. The binding
constant between receptor 1 and Hg2+ and Pb2+ was estimated by Benesi-Hildebrand plot and equations. The binding
constants have been found to be Ka= 3.43286 10â6 and Ka= 2.84079 10â6 M for Hg2+ and Pb2+, respectively. The limit of
detection (LOD) for Hg2+and Pb2+by receptor 1are down to 7.44 10â10 M and 1.26 10â9 M, respectively. In addition,
Jobâs plot analysis reveals 1:2 binding stoichiometry between the receptor 1 and Pb2+ and Hg2+ cations