Electronic Supplementary Material (ESI) for RSC Advances.
This journal is © The Royal Society of Chemistry 2016
Synthesis of a dihydroquinoline based fluorescent cyanine for
selective, naked eye, and turn off detection of Fe3+ ions.
K.Vijay, C. Nandi, and Shriniwas D. Samant*
Section
1
2
3
Contents
Detection Limit Calculation
Fluorescence Study
Spectral data
1 Detection Limit Calculation
Fluorescence intensity (a.u)
920
900
880
860
840
820
0.0
0.2
0.4
0.6
0.8
1.0
Equivalents of Fe3+
The detection limit of probe 8 for Fe3+ was estimated to be of 20.2 × 10−9 M. To establish
the detection limit, a graph of minimum equivalents of Fe3+ versus fluorescence intensity
was plotted. The point where a good sensitivity was observed was obtained by
extrapolating the lines.
Equation used for calculating detection limit (DL)
Detection Limit = Conc. of probe 8 x Equiv. of titrant at which change observed.
Therefore;
DL = 9.13 x 10-7 × 0.02 = 20.2 x 10-9 M.
2
Fluorescence Study
Plane dye
Dye + Ag+
Dye + Al3+
Dye + Ba2+
Dye + Ca2+
Dye + Cd+
Dye + Co2+
Dye + Cr3+
Dye + Cs+
Dye + Cu+
1000
Fl. intensity (a.u)
800
600
Dye + Cu2+
Dye + Fe2+
Dye + Hg2+
Dye + In3+
Dye + K+
Dye + Li+
Dye + Mg2+
Dye + Mn2+
Dye + Na+
Dye + Ni2+
Dye + Pb2+
Dye + Sb3+
Dye + Sn2+
Dye + Sr2+
Dye + Zn2+
Dye + Fe3+
400
200
0
500
550
600
650
700
Wavelength in nm
Fluorescence response curve of probe 8 (9.13 x 10-7 M) on mixing with 10 equivalents of
various metals.
The metals tested were from the corresponding compounds of AgNO3, AlCl3, BaCl2.2H2O,
CaCl2, CdCl2.5H2O, CoCl2.2H2O, CrCl3.6H2O, CsCl, CuCl, CuCl2, FeCl2.4H2O, HgCl2,
InCl3, KCl, LiCl, MgCl2.6H2O, MnCl2.2H2O, NaCl, NiCl2.6H2O, PbCl2, SbCl3, SnCl2.2H2O,
SrCl2.6H2O, and ZnCl2.
3
i.
NMR Spectra
1,2,2,4-Tetramethyl-1,2-dihydroquinoline
N
ii.
1,2,2,4-Tetramethyl-1,2-dihydro-6-quinolinecarbaldehyde
O
H
N
iii.
1HNMR
of 7-methyl-2-phenylimidazo[1,2-a]pyridine
N
N
iv.
13CNMR
of 7-methyl-2-phenylimidazo[1,2-a]pyridine
N
N
v.
1HNMR
of 7-methyl-2-phenylimidazo[1,2-a]pyridinium iodide
I
N
N
vi.
13CNMR
of 7-methyl-2-phenylimidazo[1,2-a]pyridinium iodide
I
N
N
vii.
1HNMR
of (E)-1-methyl-2-phenyl-7-(2-(1,2,2,4-tetramethyl-1,2-dihydroquinolin6-yl)vinyl)imidazo[1,2-a]pyridin-1-ium iodide:
N
N
I
N
viii.
13CNMR
of (E)-1-methyl-2-phenyl-7-(2-(1,2,2,4-tetramethyl-1,2-dihydroquinolin6-yl)vinyl)imidazo[1,2-a]pyridin-1-ium iodide:
N
N
I
N