Solvent Controlled Colorimetric and Fluorometric Detection of Fe2+ and Cu2+ Ions by Naphthaldimine-Glucofuranose Conjugate

• Published in: Journal of fluorescence Vol. 32; no. 2; pp. 745 - 758
• Main Authors: Loya, Mini, Dolai, Bholanath, Atta, Ananta Kumar
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-03-2022; Springer Nature B.V
• Subjects: Absorbance; Analytical Chemistry; Binding; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedicine; Biophysics; Biotechnology; Colorimetry; Conjugates; Copper; Density functional theory; Dimethyl sulfoxide; Emission analysis; Ferrous ions; Fluorescence; Fourier transforms; Infrared spectroscopy; Mass spectrometry; Mathematical analysis; NMR; Nuclear magnetic resonance; Original Article; Titration; Sugar conjugate; Cu; Fluorometric; Fe; Colorimetric
• ISSN: 1053-0509; 1573-4994
• DOI: 10.1007/s10895-021-02854-6

The sensing properties of naphthaldimine-glucofuranose conjugates
1
and
2
towards metal ions were investigated by
1
H NMR titration, Fourier-transform infrared spectroscopy (FTIR), absorbance, and fluorescence spectroscopic methods. The absorbance and fluorescence studies indicated that compound
1
formed coordination with Fe
2+
and Cu
2+
ions in dimethyl sulfoxide (DMSO) through color changes yellow to brown and colorless, respectively. The Job's plots using absorbance data showed metal–ligand binding ratio is 1:1 for both cases. The formation of
1-
Fe
2+
and
1-
Cu
2+
complexes have been analyzed by absorption and emission spectroscopy, high-resolution mass spectrometry (HRMS) data, FTIR,
1
H NMR titration experiment, and density functional theory (DFT) calculations. The detection limits of naphthaldimine sugar conjugate
1
towards Fe
2+
/Cu
2+
were calculated from UV–vis and fluorescence data according to the standard method. The sugar-naphthaldimine conjugate
2
has been used to establish the binding mode of
1
with Fe
2+
or Cu
2+
ions in DMSO.