2+
2+
Li-Jun Ma 1 *, Liping Chen 1 , Guirong Chen 1 , Hong-Wei Li 2 *, Liting Yang 1 , Yuqing Wu 2 , Dan
Wang 1 and Jiewan Xie 1
1
School of Chemistry and Environment, South China Normal University, Guangzhou
510006, China
2
State key Laboratory of Supramolecular Structure and Materials, Jilin University, No.
2699 Qianjin Street, Changchun 130012, China
Experimental details:
All chemicals were obtained from commercial suppliers and used without further purification. NMR experiments were performed on a Varian NMR Systems 400 MHz spectrometer using TMS as an internal standard. Fluorescence spectra were measured on a HITACHI F-2500 fluorescence spectrophotometer. The measurements of UV–vis absorption spectra were carried out with a SHIMADZU UV-1700 Spectrophotometer.
1. Measurements of Fluorescence spectra
All the fluorescent experiments were carried out in methanol/water solutions at
298 K.
Fluorescence titration was performed in methanol/water solutions using respective chloride salt of metal ions (except for AgNO
3
and Cr(NO
3
)
3
).
2. Measurements of Ultraviolet Absorption Spectroscopy
The measurements of UV–vis absorption spectra were carried out with a
SHIMADZU UV-1700 Spectrophotometer. The concentration of 1 in all the UV–vis experiments is 10.0 × 10
−6
mol · L
−1
in methanol/water solutions.

3. NMR experiments
NMR spectra of 1 (9.0 mmol) in the absence and presence of CuCl
2
/HgCl
2
were measured in methanold
4
by using Varian NMR Systems 400MHz spectrometer at room temperature.
4. Experiments data
2500
2000
1500
1000
500
H-his(Trt)-OH
Fmoc-his(Trt)-OH
Fig. S1 Fluorescent spectra of 1 (Nalpha-[(9H-Fluoren-9-ylmethoxy)carbonyl]-tele-
(triphenylmethyl)-L-histidine, Fmoc-his(Trt)-OH, 10.0

M) and H-his(Trt)-OH (10.0

M) in 3:1 CH
3
OH/H
2
O, λ ex
= 300 nm.
0
0
300 310 320 330 340 350 360 370
Wavelength / nm
-5
-10
-15
-20
0.0
0.2
0.4
0.6
[
Cu
2+
]
-1
/ 10
6
M
0.8

Fig. S2 Estimation of binding constant for 1 (10.0

M) with Cu
2+
(0.0
-
70.0

M) in
3:1 CH
3
OH/H
2
O (pH 6.6) at room temperature. The plot based on the intensity changes at 306 nm with a 1:1 binding model: I
0
/ ( I I
0
) versus [Cu
2+
]
-1
(R
2
= 0.999) in 3:1
CH
3
OH/H
2
O.
0.20
(a)
0.15
Fmoc-his(Trt)-OH
H-his(Trt)-OH
0.10
0.05
0.20
0.15
0.10
0.00
240 250 260 270 280 290 300 310 320 330 340
Wavlength / nm
0.30
0.25
(b)
0.05
0.00
240 250 260 270 280 290 300 310 320
Fig. S3 (a) The Uv-vis spectra of 1 (Fmoc-his(Trt)-OH, 10.0

M), and H-his(Trt)-OH
(10.0

M) in 3:1 CH
3
OH/H
2
O. (b) The Uv-vis spectra of 1
(10.0 µM) in 3:1
CH
3
OH/H
2
O (pH 6.6) upon addition of HgCl
2
with different concentration (0.0, 2.0,
4.0, 6.0, 8.0, 10.0, 12.0, 20.0, 35.0, 50.0

M).

-0.1
-0.2
-0.3
-0.4
I 0
-0.5
-0.6
-0.7
Hg2+
Cu2+
-0.8
2:1 3:1 4:1
CH3OH/H2O
9:1
Fig. S4 ( I I
0
)/ I
0
ratios of 1 at 306 nm after the addition of 5 equivalent Cu 2+ and Hg 2+ in CH
3
OH/H
2
O solutions (pH 6.6) with different solvent ratio with 1 (10.0 µM).
-6
I
0
/(I-I
0
)
-5
-4
-3
-2
-1
0
Cu/Zn Cu/Ag Cu/Cr Cu/Ni Cu/Cd Cu/Mn Cu/Co Cu/Ca Cu/Hg Cu/Pb
Fig. S5 I
0
/( I I
0
) ratios at 306 nm of 1 (10.0 µM) upon addition of Cu
2+
(6.0

M) and
Zn
2+
, Ag
+
, Cr
3+
, Ni
2+
, Cd
2+
, Mn
2+
, Co
2+
, Ca
2+
, Hg
2+
, Pb
2+
(12.0

M), respectively, in
3:1 CH
3
OH/H
2
O (pH 6.6) .

Fig. S6 Atomic numbering of 1 .
(A) (B)
H(5)
H(4)
(a)
(a)
(b)
(b)
(c)
7.8
7.5
7.2
6.9 4.5
4.0
3.5
3.0
ppm
180 160 140 120 80 70 60 50 40 30 20 ppm
Fig. S7 (A) Selection region of the
1
H NMR spectra of (a) 1 (9.0 mM), (b) 1 -Hg
2+
(2:1 mol/mol), and (c) 1 -Hg 2+ (1:2 mol/mol); (B) Selection region of the 13 C NMR spectra of (a) 1 (9.0 mM), (b) 1 -Hg 2+ (1:2 mol/mol); in CD
3
OD.
Table S1 Some proton chemical shifts (
δ
, in ppm) of the 1 and its associated complex with Hg
2+
(1:Hg
2+
, 1:2, mol/mol ); atomic numbering is shown in Fig. S11 .
1 2(1) 2(2) 4 5 6 7
1 4.424-4.389 3.168-3.121 2.922-2.861 6.844 7.262-7.231 4.267-4.168 4.121-4.071
1 -Hg
2+
4.461-4.427 3.249-3.200 3.028-2.966 6.925
 δ / ppm 0.038 0.081 0.106 0.081
7.830
0.568
4.251-4.164 4.119-4.071
-0.016 -0.002

Table S2 Carbon-13 chemical shifts (
δ
, in ppm) for 1 and its complex with Hg
2+
(1:Hg
2+
, 1:2, mol/mol ); atomic numbering is shown in Fig. S11.
C OOH
NH-
C1
C2
C
Fmoc
Fmoc
C3
Fmoc
C4
Fmoc
C5
Fmoc
C6
Fmoc
Trt-
C1
C2
C3
C4
C3
C4
C5
C1
C2
C6
OO
C
Trt
Trt
Trt
Trt
1
173.878
1 -Hg
2+
173.638
156.868 158.836
Carbons of Fmoc group
143.787/143.748 143.771/143.729
119.491 119.493
124.926/124.857 124.928/124.876
127.366 127.370
126.765/126.729 126.788/126.748
141.111/141.095 141.104/141.088
76.038 76.416
Carbons of Trityl group
141.717 141.446
129.421
127.887
129.415
127.961
128.024 128.130
Carbons of iminazole
135.300
120.033
135.277
120.386
137.509
Other carbons
138.113
54.245
29.689
66.667
54.056
29.252
66.721
 δ
/ ppm
-0.24
-0.03
-0.016
0
0.019
0.004
0.023
-0.007
0.378
-0.257
-0.006
0.074
0.106
0.023
0.353
0.604
-0.189
-0.437
0.054

0
-5
-10
(a)
-15
-20
-25
0.0
0.2
0.4
0.6
[
Cu
2+ ] -2
/ 10
12
M
0.8
1.0
0
-2
-4
-6
-8
-10
(b)
-12
0.0
0.2
0.4
0.6
[
Hg
2+ ] -2
/ 10
12
M
-2
0.8
1.0
Fig. S8 (a) Estimation of binding constant for 1 with Cu
2+
(1.0
40.0

M) 1:1
CH
3
OH/H
2
O at room temperature. The plot based on the intensity changes at 317 nm with a 1:2 binding model: I
0
/( I I
0
) versus [Cu 2+ ] -2 (R 2 = 0.998) in 1:1 CH
3
OH/H
2
O; (b)
Estimation of binding constant for 1 with Hg
2+
(1.0
-
40.0

M) in 1:1 CH
3
OH/H
2
O at room temperature. The plot based on the intensity changes at 317 nm with a 1:2 binding model: I
0
/ ( I I
0
) versus [Hg
2+
]
-2
(R
2
= 0.997).

5000
4000
3000
2000
1000
1 + Cu 2+
1 only
1 + Cu 2+ + EDTA
0
300 310 320 330 340 350 360 370
Wavelength / nm
Fig. S9 Fluorescent spectra of 1 (10.0 µM) in 1:1 CH
3
OH/H
2
O (pH 6.6) upon addition of CuCl
2
(4.5 µM) and EDTA (18.0 µM),
 ex
= 300 nm. The results of Hg
2+
are similar with that of Cu
2+
.
3
2
1
0
5
4
7
6
I
304
/I
317
Cu/Ni Cu/Co Cu/Cd Cu/Zn Cu/Ag Cu/Ca Cu/Mn Cu/Pb Cu/Cr
Fig. S10 The ratio of fluorescence intensity of 304 nm and 317 nm of 1 (10.0 µM) upon addition of Cu
2+
(5.5

M) and Ni
2+
, Co
2+
, Cd
2+
, Zn
2+
, Ag
+
, Ca
2+
, Mn
2+
, Pb
2+
,
Cr
3+
(11.0

M), respectively, in 1:1 CH
3
OH/H
2
O (pH 6.6) . The results of Hg
2+
are similar with that of Cu 2+ .

3.5
3.0
2.5
2.0
1.5
Cu
2+
Hg
2+
1.0
10:0 9:1 4:1 3:1 2:1 9:5 3:2 6:5 1:1 4:5
CH3OH:H2O
( v/v
)
Fig. S11 The ratio of fluorescence intensity changes at 304 nm and 317 nm of 1 (10.0
µM) after the addition of CuCl
2
(3.5

M) and HgCl
2
(3.5

M) in different ratios of
CH
3
OH/H
2
O. The results of Hg
2+
are similar with that of Cu
2+
.
6. Molecular simulation
To investigate the interaction of Cu 2+ with probe 1 , density functional theory calculations were performed with the B3LYP functional and the mixed “Double-ζ” quality basis sets 6-31G(d) for C, H, O, N, S and LANL2DZ for Cu. Optimization of the complexes was performed without any constraints for all the complexes. All calculations were carried out using Gaussian 09
1
.
References:
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