Supporting Information
Fluorescence turn on sensor for sulfate ion in aqueous medium using
tripodal-Cu2+ ensemble
Md. Najbul Hoque, Arghya Basu and Gopal Das*
Department of Chemistry, Indian Institute of Technology Guwahati,
Assam-781039, India
Email: gdas@iitg.ernet.in
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Fig. S1. 1H-NMR (400 MHz) spectra of 1-Hydroxy-naphthalene-2-carboxylic acid methylester 1 in
CDCl3 at 298 K.
Fig. S2. 13C-NMR (100 MHz) spectra of 1-Hydroxy-naphthalene-2-carboxylic acid methylester 1 in
CDCl3 at 298 K.
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Fig. S3. 1H-NMR (400 MHz) spectra of tripodal ester 2 in CDCl3 at 298 K.
Fig. S4. 13C-NMR (100 MHz) spectra of tripodal ester 2 in CDCl3 at 298 K.
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Fig. S5. 1H-NMR (400 MHz) spectra of [Na2L] in D2O at 298 K.
Fig. S6. FT-IR spectra of 1-Hydroxy-naphthalene-2-carboxylic acid methylester 1 (KBr pellet).
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Fig. S7. FT-IR spectra of tripodal ester 2 (KBr pellet).
Fig. S8. FT-IR spectra of [Na2L] (KBr pellet).
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Fig. S9. UV-Vis spectra of [Na2L] in buffer medium.
Fig. S10. Calculation of binding constant of L-Cu2+ complex from the fluorescence titration data
using log [(F-F0)/(Fm-F)] vs. log [Zn2+].
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Fig. S11. Plot of the fluorescence intensity of L-Cu2+ (at 412 nm) as a function of sulfate anion
concentration.
Fig. S12. Fluorescence intensity of L-Cu2+ upon addition of sulfate ion at different pH in tris-HCl
buffer solution.
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Fig. S13. ESI-Mass spectrum of tripodal ester 2 (INSET: Calculated Mass spectra).
Fig. S14. ESI-Mass spectrum of [L•Na2] (INSET: Calculated Mass spectra).
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Fig. S15. ESI-Mass spectrum of L-Cu2+ (INSET: Calculated Mass spectra).
Fig. S16. ESI-Mass spectrum of L-Cu2+ after addition of sulfate anion.
References
1. Benesi H, Hildebrand J (1949) J Am Chem Soc 71:2703-2707.
2. Connors KA, (1987) Binding Constants, John Wiley & Sons, New York, 339-343.
3. Valeur B, (2000) Molecular Fluorescence, Wiley-VCH, Weinheim, 339-346.
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