1

Instant hydrogel formation of terpyridine-based complexes

triggered by DNA via non-covalent interaction

Lijun Geng, Xudong Yu*, Yajuan Li, Yanqiu Wang, Yongquan Wu, Jujie Ren, Fengfeng Xue, Tao Yi

Lijun Geng, Xudong Yu*, Yajuan Li, Yanqiu Wang, Jujie Ren

College of Science, Hebei University of Science and Technology,Yuhua Road 70, Shijiazhuang 050080, China

E-mail: chemyxd@163.com (X. Yu)

Yongquan Wu

School of Chemistry and Chemical Engineering, Gannan Normal University, Ganzhou, Jiangxi 341000, China

Fengfeng Xue, Tao Yi

Department of Chemistry, and Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, 220 Handan Road, Shanghai 200433, China

Electronic Supplementary Material (ESI) for Nanoscale.This journal is © The Royal Society of Chemistry 2019

2

1. Synthesis of ligand TEG, Zn(II)(TE)I2 , Zn(II)(TEG)L, and Cd(II)(TEG)Cl2.

N

N

N

Br

+N

O

Br2

CHO

N

N

NHN

NH3

1

NH2

NH2

H2N

2 (TE)

+

N

N

N

NH

HN

O

OH

OH

OH

OHOH

OO

OH

OHOH

HO

4 (TEG)

ZnL

N

N

N

NH

HN

O

OH

OH

OH

OHOHZnL

5a-5h (Zn(II)(TEG)L)

N

N

NHN NH2

Zn

ZnI2

II

3 (Zn(II)(TE)I2)

L=F-, Cl-, Br-, I-, AcO-, SO42-, NO3

-, C6H11O7-

Scheme S1. The synthesis procedure of TEG and Zn2+-based complexes.

The synthesis of 1 and 2(TE) could be seen in literature 1 and 2, respectively.

Synthesis of Zn(II)(TE)I2:

The solution of Compound TE (0.73 g, 2 mmol) dissolved in methanol (20 mL) was

added to a stirring solution of ZnI2 (1.27 g, 4 mmol) dissolved in methanol (10 mL)

and continued stirring at room temperature for 3h. The resulting product was filtered

and the solid was washed with methanol to give a yellow powder (0.96 g, yield: 70%).

Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 9.16-8.92 (m, 6H), 8.42-8.36 (m, 2H),

8.22 (d, J = 8.5 Hz, 1H), 7.96-7.81 (m, 4H), 6.85 (d, J = 9.0 Hz, 1H), 3.48 (t, J = 5.0

Hz, 2H), 3.34 (t, J = 5.5 Hz, 2H). 13C NMR (125 MHz, DMSO-d6): 58.51, 60.48,

112.86, 118.22, 122.66, 123.35, 127.70, 129.80, 141.41, 147.77, 148.40, 149.09,

3

151.28, 154.61. MS calc. for [C23H21I2N5Zn+Na]+: 711.9; Found: 712.1. Element

Anal. Calcd for C23H21I2N5Zn, C, 40.23; H, 3.08; N, 10.20 %. Found: C, 40.16; H,

3.01; N, 10.13 %.

Synthesis of TEG:

Compound TE (1 g, 2.7 mmol) and D-(+)-Gluconic acid δ-lactone (477 mg, 2.7 mmol)

were refluxed in ethanol (60 mL) for 14 h. The separated solid was filtered and

recrystallized in water to give a pale yellow solid (0.66 g, 45%). Mp: 201-202°C. 1H

NMR (500 MHz, DMSO-d6): 8.78 (d, J = 4.0 Hz, 2H), 8.68 (s, 1H), 8.66 (s, 3H),

8.06-8.03 (m, 2H), 7.75 (d, J = 4.0 Hz, 2H), 7.55-7.52 (m, 2H), 6.81 (d, J = 8.0 Hz,

2H), 6.22 (t, J = 5.5 Hz, 1H), 4.06 (d, J = 3.5 Hz, 2H), 3.98 (s, 1H), 3.62 (d, J = 9.5

Hz, 1H), 3.54 (s, 2H), 3.44-3.36 (m, 9H), 3.22 (d, J = 6.0 Hz, 2H). 13C NMR (125

MHz, DMSO-d6): 40.85, 45.60, 66.65, 73.42, 74.77, 75.57, 76.81, 115.71, 119.45,

124.12, 127.60, 140.65, 152.55, 158.64, 176.27. MS calc. for [C29H31N5O6+H]+:

546.2; Found: 546.1. Element Anal. Calcd for C29H31N5O6, C, 63.84; H, 5.73; N,

12.84 %. Found: C, 63.72; H, 5.65; N, 12.71 %.

Synthesis of Zn(II)(TEG)L

5a. Zn(II)(TEG)F2

The solution of ZnF2 (132 mg, 1.3 mmol) dissolved in water (10 mL) was added to a

stirring solution of compound TEG (0.7 g, 1.3 mmol) dissolved in 2-methoxyethanol

(30 mL) and continued stirring at room temperature for 5 h. The resulting product was

filtered and the solid was washed with water and 2-methoxyethanol to give a yellow

powder；Yield: 0.64 g (76%). Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 8.38-

8.05 (m, 2H), 7.48-6.80 (m, 10H), 6.27-5.91 (m, 2H), 4.38 (s, 1H), 4.16 (s, 1H), 3.93-

3.89 (m, 4H), 3.71-3.62 (m, 3H), 3.22-2.80 (m, 3H), 2.24 (s, 1H). MS calc. for

[C29H31F2N5O6Zn+K]+: 688.1; Found: 688.8. Element Anal. Calcd for

C29H31F2N5O6Zn, C, 53.67; H, 4.81; N, 10.79 %. Found: C, 53.78; H, 4.70; N, 10.65

%.

Compound 5b and 5c were synthesized as the same procedure given for compound

5b. Zn(II)(TEG)(SO4)

ZnSO4 (375 mg, 1.3 mmol), water (15 mL), Yield: 0.75 g (82%). Mp: > 250°C. 1H

NMR (500 MHz, DMSO-d6): 8.56-8.54 (m, 4H), 7.75-7.32 (m, 4H), 6.98-6.95 (m,

4H), 6.73-6.70 (m, 2H), 5.81-5.78 (m, 2H), 4.37 (t, J = 3.5 Hz, 1H), 4.15 (s, 1H),

3.86-3.71 (m, 4H), 3.40-3.31 (m, 2H), 2.95 (s, 1H). MS calc. for [C29H31N5O10SZn-

4

ZnSO4 +Na]+: 568.2; Found: 568.5. Element Anal. Calcd for C29H31N5O10SZn, C,

49.26; H, 4.42; N, 9.91 %. Found: C, 49.13; H, 4.30; N, 9.86 %.

5c. Zn(II)(TEG)(C6H11O7)2

Zinc gluconate (577 mg, 1.3 mmol), water (15 mL), Yield: 0.95 g (73%). Mp: >

250°C. 1H NMR (500 MHz, DMSO-d6): 8.46-8.43 (m, 4H), 7.72-7.46 (m, 8H), 6.27-

6.25 (m, 2H), 4.35 (s, 1H), 4.11-4.09 (m, 2H), 3.84-3.65 (m, 6H), 3.45 (t, J = 7.5 Hz,

3H), 3.18-3.16 (m, 3H), 2.86-2.85 (m, 1H). MS calc. for [C41H53N5O20Zn-

ZnC12H22O14+Na]+: 568.2; Found: 568.5. Element Anal. Calcd for C41H53N5O20Zn, C,

49.18; H, 5.34; N, 6.99 %. Found: C, 49.27; H, 5.26; N, 6.82 %.

5d. Zn(II)(TEG)Cl2

The solution of ZnCl2 (177 mg, 1.3 mmol) dissolved in methanol (8 mL) was added to

a stirring solution of compound TEG (700 mg, 1.3 mmol) dissolved in 2-

methoxyethanol (30 mL) and continued stirring at room temperature for 6h. The

resulting product was filtered and the solid was washed with methanol and 2-

methoxyethanol to give an orange powder; Yield: 0.62 g (70%). Mp: > 250°C. 1H

NMR (500 MHz, DMSO-d6): 8.91 (s, 4H), 8.81 (d, J = 4.0 Hz, 2H), 8.30 (t, J = 7.0

Hz, 2H), 8.15 (d, J = 8.0 Hz, 2H), 7.95 (t, J = 6.0 Hz, 1H), 7.85 (t, J = 6.0 Hz, 2H),

6.81 (d, J = 8.0 Hz, 2H), 6.53 (s, 1H), 5.48 (d, J = 5.0 Hz, 1H), 4.58 (d, J = 5.0 Hz,

1H), 4.54 (d, J = 5.5 Hz, 1H), 4.50 (d, J = 7.0 Hz, 1H), 4.37 (t, J = 5.5 Hz, 1H), 4.06

(t, J = 4.5 Hz, 1H), 3.99-3.97 (m, 1H), 3.63-3.59 (m, 1H), 3.54-3.47 (m, 3H), 3.42-

3.40 (m, 1H), 3.25 (t, J = 7.0 Hz, 3H). 13C NMR (125 MHz, D2O): 40.90, 65.45, 73.21,

73.95, 75.01, 120.19, 118.91, 118.15, 177.43. MS calc. for [C29H31Cl2N5O6Zn+Na]+:

702.1; Found: 702.2. Element Anal. Calcd for C29H31Cl2N5O6Zn: C, 51.08; H, 4.58; N,

10.27 %. Found: C, 51.23; H, 4.63; N, 10.13 %.

For compounds 5e-5h the same procedure as for compounder 5d was used.

5e. Zn(II)(TEG)Br2

ZnBr2 (293 mg, 1.3 mmol), reaction solvent: methanol (15 mL), yield: 0.8 g (80%).

Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 8.83 (d, J = 4.0 Hz, 6H), 8.24 (s, 2H),

8.09 (t, J = 5.0 Hz, 2H), 7.98-7.84 (m, 4H), 6.74 (d, J = 7.5 Hz, 2H), 6.53 (s, 1H),

5.51 (d, J = 5.0 Hz, 1H), 4.61 (d, J = 5.0 Hz, 1H), 4.57 (d, J = 5.0 Hz, 1H), 4.52 (d, J

= 7.5 Hz, 1H), 4.39 (t, J = 6.0 Hz, 1H), 4.06 (t, J = 4.0 Hz, 1H), 3.98 (t, J = 3.5 Hz,

1H), 3.62-3.47 (m, 4H), 3.22 (t, J = 6.0 Hz, 3H). 13C NMR (125 MHz, DMSO-d6):

37.52, 42.11, 63.41, 70.24, 71.55, 72.32, 73.56, 73.91, 111.94, 116.99, 122.18, 126.90,

129.12, 146.99, 148.35, 151.38, 153.86, 173.11. MS calc. for [C29H31Br2N5O6Zn+H]+:

5

771.8; Found: 772.0. Element Anal. Calcd for C29H31Br2N5O6Zn, C, 45.19; H, 4.05; N,

9.09 %. Found: C, 45.32; H, 4.16; N, 8.97 %.

5f. Zn(II)(TEG)I2

ZnI2 (413 mg, 1.3 mmol), reaction solvent: methanol (10 mL), yield: 0.78 g (70%).

Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 9.20 (s, 1H), 9.13 (d, J = 8.0 Hz, 1H),

9.01-8.90 (m, 4H), 8.40-8.16 (m, 5H), 7.93-7.90 (m, 3H), 7.47 (t, J = 6.0 Hz, 1H),

6.92 (d, J = 8.5 Hz, 1H), 6.83 (d, J = 8.5 Hz, 1H), 5.48 (s, 1H), 4.57-4.50 (m, 4H),

4.38-4.35 (m, 1H), 4.06 (d, J = 3.5 Hz, 1H), 3.98 (s, 1H), 3.61-3.46 (m, 6H). 13C

NMR (125 MHz, DMSO-d6): 37.47, 42.07, 63.37, 70.21, 71.51, 72.27, 73.50, 112.03,

117.30, 122.47, 127.05, 129.24, 147.43, 148.17, 151.43, 154.09, 173.07. MS calc. for

[C29H31I2N5O6Zn+H]+: 866.0; Found: 865.9. Element Anal. Calcd for

C29H31I2N5O6Zn, C, 40.28; H, 3.61; N, 8.10 %. Found: C, 40.41; H, 3.54; N, 8.23 %.

5g. Zn(II)(TEG)(NO3)2

Zn(NO3)2 (386 mg, 1.3 mmol), reaction solvent: methanol (4 mL), yield: 0.65 g (68%).

Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 9.20 (s, 1H), 9.12 (d, J = 8.0 Hz, 1H),

9.03 (d, J = 8.0 Hz, 1H), 8.97 (s, 1H), 8.87 (s, 1H), 8.45-8.39 (m, 1H), 8.33-8.23(m,

3H), 8.16(d, J = 8.5 Hz, 1H), 8.01-7.90 (m, 3H), 7.47 (t, J = 7.0 Hz, 1H), 6.93-6.84

(m, 2H), 6.66-6.56 (m, 1H), 5.53-5.50 (m, 1H), 4.62-4.34 (m, 5H), 4.07-4.04 (m, 1H),

3.97 (s, 1H), 3.62-3.46 (m, 4H), 3.31-3.24 (m, 2H). 13C NMR (125 MHz, DMSO-d6):

37.57, 42.14, 63.44, 70.28, 71.57, 72.31, 73.54, 112.22, 117.65, 118.26, 121.47,

123.20, 127.38, 129.61, 147.67, 148.74, 149.07, 151.77, 155.05, 173.21. MS calc. for

[C29H31N7O12Zn-ZnN2O6+Na]+: 568.2; Found: 568.4. Element Anal. Calcd for

C29H31N7O12Zn, C, 47.39; H, 4.25; N, 13.34 %. Found: C, 47.52; H, 4.17; N, 13.29 %.

5h. Zn(II)(TEG)(AcO)2

Zn(AcO)2 (285 mg, 1.3 mmol), reaction solvent: methanol (15 mL), yield: 0.54 g

(57%). Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 9.20 (s, 1H), 9.13 (d, J = 8.0

Hz, 1H), 9.01-8.90 (m, 4H), 8.40-8.16 (m, 5H)，7.93-7.90 (m, 3H), 7.47(t, J = 6.0 Hz,

1H), 6.92 (d, J = 8.5 Hz, 1H), 6.83 (d, J = 8.5 Hz, 1H), 5.48 (s, 1H), 4.57-4.35 (m,

4H), 4.36 (t, J = 5.5 Hz, 1H), 4.06 (d, J = 3.5 Hz, 1H), 3.98 (s, 1H), 3.61-3.46 (m, 6H). 13C NMR (125 MHz, D2O): 41.21, 60.53, 62.74, 74.05, 75.69, 76.75, 111.51, 114.82,

122.49, 123.20, 129.67, 149.10, 153.32, 175.64. MS calc. for [C33H37N5O10Zn-H] -:

726.2; Found: 726.3. Element Anal. Calcd for C33H37N5O10Zn, C, 54.36; H, 5.12; N,

9.61 %. Found: C, 54.45; H, 5.01; N, 9.57 %.

6

Cd(II)(TEG)Cl2

The solution of CdCl2 (296mg, 1.3 mmol) dissolved in water (10 mL) was added to a

stirring solution of compound TEG (0.7 g, 1.3 mmol) dissolved in 2-methoxyethanol

(30 mL) and continued stirring at room temperature for 4 h. The resulting product was

filtered and the solid was washed with water and 2-methoxyethanol to give a yellow

powder; Yield: 0.68 g (72%). Mp: > 250°C. 1H NMR (500 MHz, DMSO-d6): 8.71 (d,

J =8.0 Hz, 2H), 8.67 (d, J =4.0 Hz, 2H), 8.61 (s, 2H), 8.13 (t, J = 7.5 Hz, 2H), 7.96 (d,

J =6.5 Hz, 3H), 7.75 (t, J = 6.0 Hz, 2H), 6.61 (d, J = 8.0 Hz, 2H), 6.38 (s, 1H), 5.51 (d,

J = 4.5Hz, 1H), 4.61- 4.52 (m, 4H), 3.50-3.46 (m, 4H), 3.35-3.32 (m, 6H). 13C NMR

(125 MHz, DMSO-d6): 39.65, 40.32, 70.69, 72.01, 72.79, 74.02, 74.36, 112.35,

118.09, 123.42, 127.14, 129.31, 149.55, 151.52, 173.53. MS calc. for

[C29H31Cl2N5O6Cd-Cl]+: 693.6; Found: 694.2. Element Anal. Calcd for

C29H31CdCl2N5O6, C, 47.79; H, 4.29; N, 9.61 %. Found: C, 47.71; H, 4.26; N, 9.65 %.

2. Other experiment data

480 520 560 600 6400

2000

4000

6000

Inte

nsity

Wavelengtn/nm

Figure S1 Fluorescent titrations of Zn(II)(TEG)I2 (10-5 M) upon the addition of DNA

in tris buffer (pH = 7.4) with λex= 454 nm (base pairs: 0-42 equiv.).

7

0.0 0.2 0.4 0.6 0.8 1.0

1200

1600

2000

2400

Inte

nsity

[DNA]/[DNA+Zn(II)(TEG)I2]

Figure S2 The Job’s plot curves of Zn(II)(TEG)I2 with DNA in water.

0.0 200.0k 400.0k 600.0k 800.0k 1.0M 1.2M 1.4M0.0

2.0x10-4

4.0x10-4

6.0x10-4

8.0x10-4

1.0x10-3

1.2x10-3

1.4x10-3 D Linear Fit of D

1/(I-

I 0)

1/[DNA]

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

1.34939E-8

Adj. R-Square 0.98743Value Standard Error

D Intercept 2.11044E-4 1.55109E-5D Slope 8.78756E-10 3.30238E-11

Figure S3 The linear fitting curve of fluorescence change of Zn(II)(TEG)I2 (10-5M)

with the addition of DNA.

Detection limit of Zn(II)(TEG)I2 toward DNA by fluorescence intensity changes at

555nm

8

n 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Intensity(Xn

)

591.8

591.0

592.1

594.6

592.7

592.8

592.8

590.2

593.1

592.2

591.4

590.6

591.3

589.7

591.2

n 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30Intensity（ Xn ）

592.7

593.6

594.1

592.8

591.3

591.7

591.9

593.3

591.9

595.1

595.7

596.6

596.0

595.5

594.7

X average = 592.8 σ = 1.764 L = 8.114 K = 4.2×104

R = 0.9874 ε = 2.0 ×1013 the detection limit: 4.06×10-13

480 520 560 600 640 6800

500

1000

1500

2000

2500

Inte

nsity

Wavelenth/nm200 250 300 350 400 450 500 550

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Abso

rban

ce

Wavelengtn/nm

a b

Figure S4 a) Fluorescent titrations of Zn(II)(TEG)(AcO)2 (10-5 M) upon the addition

of DNA in water (base pairs: 0-75 equiv.); b) UV-vis titrations of

Zn(II)(TEG)(AcO)2 (10-6 M) upon the addition of DNA.

480 520 560 600 6400

1000

2000

3000

4000

5000

6000

7000

Inte

nsity

Wavelength/nm

Figure S5 Fluorescent emission spectra for the titration of Zn(II)(TEG)(AcO)2 (10-5 M)

upon the addition of DNA in tris buffer λex = 454 nm (base pairs: 0-62 equiv.).

9

550 600 650 700 7500

500

1000

1500

2000

Inte

nsity

Wavelength/nm

0μM 5μM 15μM 22.5μM

Figure S6 The fluorescence changes of DNA/ethidium bromide hybrid (base pairs: 20

μM, ethidium bromide: 10 μM) upon the gradual addition of Zn(II)(TEG)I2.

400 450 500 550 600 6500

200

400

600

800

1000

1200

Inte

nsity

Wavelength/nm

TEG TEG+DNA

450 500 550 600 6500

400

800

1200

Inte

nsity

Wavelength/nm

2 2+DNA

a b

c

400 500 600 7000

100

200

300

400

500

600

Inte

nsity

Wavelengtn/nm

Figure S7 a) Fluorescent titrations of Zn(II)(TE)I2 (10-5 M) solution upon the addition

of DNA(base pairs: 0-128 equiv.) (λex = 454 nm); b) TEG solution (10-5 M) upon the

addition of DNA (10-4 M), λex = 340 nm; c) TE solution (10-5 M) upon the addition of

DNA (10-4 M), λex = 390 nm.

10

-0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2-6.0x10-6

-4.0x10-6

-2.0x10-6

0.0

2.0x10-6

4.0x10-6

6.0x10-6

8.0x10-6

i/A

E/VFigure S8 CV curves Zn(II)(TEG)I2 (10-5 M) in the presence of DNA (base pairs: 0-

83.2 equiv.).

-0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2-1.0x10-5

-5.0x10-6

0.0

5.0x10-6

1.0x10-5

1.5x10-5

E/V

i/A

Figure S9 CV curves Zn(II)(TE)I2 (10-5 M) in the presence of DNA (base pairs: 0-249

equiv.).

11

300 400 500 600-10-8-6-4-202468

10

Ellip

ticity

Wavelength/nm

Figure S10 CD spectral changes of DNA (base pairs: 1.65×10-4 M) with the addition

of Zn(II)(TEG)I2 (0- 3.61equv.) in water.

300 400 500-10

-8

-6

-4

-2

0

2

4

6

8

CD/m

deg

Wavelength/ nm 300 400 500-8

-6

-4

-2

0

2

4

6

8

CD/m

deg

Wavelengtn/nm

a b

Figure S11 CD spectral changes of DNA (base pairs: 1.65×10-4 M) with the addition

of Zn2+ complexes in tris buffer (pH = 7.4), for a): Zn(II)(TEG)I2 (0-2.87 equiv. ); for

b): Zn(II)(TEG)(AcO)2 (0-2.32 equiv. ) .

500 550 600 650 700 7500

100

200

300

400

Inte

nsity

Wavelength/nm500 550 600 650 700 750

0

20

40

60

80

100

120

140

160

180

Inte

nsity

Wavelength/nm

a b

Figure S12 The fluoresent titrations of Zn(II)(TEG)I2 (10-5 M) upon the addition of

ss-DNA. a) poly(AT)10 (0-1.38 equiv.); b) poly(GC)10 (0-1.13 equiv.).

12

0 200 400 600 800 1000 1200

50

100

150

200

250 (GC)10

(AT)10

Inte

nsity

[base pairs] /nM

Figure S13 The fluorescent intensity value changes of Zn(II)(TEG)I2 at 540 nm in the

presence of ss-DNA.

Table S1 The gelation properties of Zn(II)(TEG)L(25 mg mL-1) with DNA (1 equiv.

base pairs).

Zn2+ metal Complex H-C +DNAa Sonication +DNAb

Zn(II)(TEG)F2 S G I I

Zn(II)(TEG)Cl2 G G I G

Zn(II)(TEG)Br2 G G I G

Zn(II)(TEG)I2 G P I G

Zn(II)(TEG)(NO3)2 S P I I

Zn(II)(TEG)(AcO)2 S G I I

Zn(II)(TEG)(C6H11O7)2 S G I I

Zn(II)(TEG)SO4 S P S PNote: P: precipitate; S: solution; G: gel; I: insoluble; H–C: heating–cooling process. a) Assembly

of Zn2+ metal Complex/DNA hybrid (R=1:1) obtained by heating-cooling process; b) Assembly of

Zn2+ metal Complex/DNA hybrid (R=1:1, R: molecular ratio of Zn2+ metal complex and DNA

base pairs) treated by ultrasound.

13

Table S2 The gelation properties of TEG (25 mg mL-1) with DNA (1 equiv. base pairs)

in the presence of other different metal ions (1 equiv.). Note: Cd(II)(TEG)Cl2 was

synthesized and characterized.

Metal ions R.T. U

NaNO3 S P

KNO3 I I

AgNO3 S P

BaCl2 I S

Mg( (NO3)2 I I

SrCl2 I S

Fe (NO3)3 I I

Al (NO3)3 I I

Bi (NO3)3 I I

Cd(II)(TEG)Cl2 I INote: P: precipitate; S: solution; G: gel; I: insoluble; R. T.: room temperature.

2000 1500 1000 5000

40

80

120

160

200

2000 1500 1000 500

Tran

smitt

ance

(%)

Wavenumber (cm-1)

1226.91277.5

1238.4

1243.6

642.4

Zn(II)(TEG)AcO2 powder Zn(II)(TEG)AcO2/DNA hydrogel DNA powder

612.1639.2

Figure S14 The FT-IR spectra of Zn(II)(TEG)(AcO)2 powder, hydrogel of

Zn(II)(TEG)(AcO)2 /DNA hybrids (base pairs: 1 equiv), DNA powder.

14

250 300 350 400 450 500 550

-30

-20

-10

0

10

20

CD/m

deg

Wavelength/nm

Figure S15 CD spectral changes of DNA (base pairs: 1.65×10-4 M) with the addition

of Zn(II)(TEG)I2 (0-3.24 equiv.) in phosphate buffer saline (pH = 7.4).

a b

Figure S16 TEM images of Zn(II)(TEG)L assembly; a) solution of

Zn(II)(TEG)(AcO)2 after evaporation; b) suspension of Zn(II)(TEG)I2. Scale bar: 100

nm, 1 μm.

15

-0.2 0.0 0.2 0.4 0.6 0.8 1.0-4.0x10-4

-3.0x10-4

-2.0x10-4

-1.0x10-4

0.0

1.0x10-4

2.0x10-4

3.0x10-4

i/A

E/V

Zn(II)(TEG)I2/DNA gel

200 300 400 500 600 700-40

-20

0

20

40

60

80

100

Ellip

ticity

Wavelength/nm

Zn(II)(TEG)I2/DNA gel Zn(II)(TEG)(AcO)2/DNA gel

200 300 400 5000.0

0.5

1.0

1.5

2.0

2.5 Solution of Zn(II)(TEG)I2 Zn(II)(TEG)I2/DNA gel

Abso

rban

ce

Wavelength/nm300 400 500 600 700

0.10

0.15

0.20

0.25

0.30

Abso

rban

ce

Wavelength/nm

gel of Zn(II)(TEG)I2/DNA hybrid

a b

c d

Figure S17 a) Uv-vis spectra of Zn(II)(TEG)I2 solution (10-6 M) and gel of

Zn(II)(TEG)I2 /DNA hybrid (Zn(II)(TEG)I2: 25 mg/mL, base pairs: 1.75×10-2 M); b)

Uv-Vis spectra of Zn(II)(TEG)I2 /DNA gel; c) CD spectra of Zn2+ metal

complex/DNA hybrid hydrogels (Zn2+ complex: 25 mg/mL, base pairs:1 equiv.) ; d)

CV curve of Zn(II)(TEG)I2/DNA hybrid hydrogel.

500 550 600 650 700 750 8000

100

200

300

400

500

600

700

Zn(II)(TEG)(AcO)2 sol Zn(II)(TEG)(AcO)2/DNA hydrogel

Inte

nsity

Wavelength/nm450 500 550 600 650 700 750 800

0

200

400

600

800

Zn(II)(TEG)I2 suspension Zn(II)(TEG)I2/DNA hydrogel

Inte

nsity

Wavelength/nm

a b

Figure S18 a) Fluorescent emission spectra for Zn(II)(TEG)I2 suspension (25 mg/mL)

and gel of Zn(II)(TEG)I2 /DNA hybrid (base pairs: 1.75×10-2 M); b) Fluorescent

emission spectra of Zn(II)(TEG)(AcO)2 solution (25 mg/mL) and gel of

Zn(II)(TEG)(AcO)2/DNA hybrid (base pairs: 3.5×10-2 M). For

Zn(II)(TEG)(AcO)2/DNA hydrogel: 24 fold at λex = 577 nm; for Zn(II)(TEG)I2/DNA

hydrogel: 41 fold at λex = 587 nm.

16

5 10 15 20 250

20

40

60

80

100

2θ

Inte

nsity

Zn(II)(TEG)(AcO)2 powder Zn(II)(TEG)(AcO)2/DNA hydrogel

2.02

1.14 0.78

0.600.52

0.50

0.460.42

0.40

1.94 1.200.54

0.46 0.384.04

Figure S19 XRD data of Zn(II)(TEG)(AcO)2 powder and xerogel of

Zn(II)(TEG)(AcO)2/DNA hybrid (base pairs: 1 equiv.).

5 10 15 20 250

20

40

60

80

100

2θ

0.942.10

0.440.78

Inte

nsity

Zn(II)(TG)I2+DNA hydrogel Zn(II)(TG)I2 powder

2.10 0.50

0.40

0.78

0.44 0.400.94

Figure S20 XRD data of Zn(II)(TEG)I2 powder and xerogel of Zn(II)(TEG)I2/DNA

hybrid (base pairs: 0.6 equiv.).

17

5 10 15 20 250

20

40

60

80

100

2θ

Inte

nsity

Figure 21 XRD data of DNA powder.

a b

Figure S22 Photos of the a) Zn(II)(TEG)I2/(AT)10 hybrid gel (base pairs: 1 equiv.); b)

Zn(II)(TEG)I2/(GC)10 hybrid gel (base pairs: 1 equiv.).

a b

Figure S23 TEM images of Zn(II)(TEG)I2/poly(AT)10 hybrid gel. Scale bar: 2 µm, 1

18

µm.

Figure 24 TEM images of Zn(II)(TEG)I2/(CG)10 hybrid gel. Scale bar: 2 µm, 1 µm.

0.1 1 101

10

100

1000

10000

Zn(II)(TEG)(AcO)2/DNA gel G' G"

Zn(II)(TEG)I2/DNA gel G' G''

Zn(II)(TEG)I2gel+DNA G' G''

Stor

age M

odul

us G

'(Pa)

Loss

Mod

ulus

G''(P

a)

Frequency f (Hz)

a

b0.1 1 10

1

10

Zn(II)(TEG)I2 hydrogel

G' G''

Stor

age M

odul

us G

'(Pa)

Loss

Mod

ulus

G''(P

a)

Frequency f (Hz)

19

Figure S25. a) Frequency sweep experiments of G′ and G″ for Zn(II)(TEG)I2

hydrogel gel with strain at 0.1%; b) Frequency sweep experiments of G′ and G″

for DNA hydrogels with Zn(II)(TEG)I2, Zn(II)(TEG)(AcO)2 with strain at 0.1%.

Table S3 The gradually gelation paths of DNA and DNA analogues in the presence of

different Zn2+ metal complexes (Zn2+ complexes: 25 mg/mL, DNA or DNA analogues

L: 1equiv. ).

Zn(II)(TEG)(C6H11O7)2

Zn(II)(TEG)SO4

Zn(II)(TEG)(NO3)2

Zn(II)(TEG)(AcO)2

R.T.

U R.T. U R.T. U R.T. U

AMP S OG P OG P P S OG

ADP OG S OG P TG S P P

ATP OG P P P P OG OG TG

st-DNA

OG I P P P I OG I

(GC)10 S S S S S S S S

(AT)10 S S S S S S S S

FAD P P P P P P S S

NADP S S P P P P S S

Note: U: ultrasound; P: precipitate; S: solution; I: insoluble; OG: opaque gel; TG: transparent gel. R. T.

room temperature.

20

Table S4 The gelation properties of DNA and DNA analogues in the presence of

different Zn2+ metal complexes (Zn2+ complexes: 25 mg/mL, DNA or DNA analogues

L: 1equiv.).

Zn(II)(TEG)F2

Zn(II)(TEG)I2

Zn(II)(TEG)Cl2

Zn(II)(TEG)Br2

R.T. U R.T. U R.T. U R.T. U

AMP S OG I P I OG I OG

ADP P OG I OG I OG I OG

ATP OG OG I P I P I P

st-DNA

OG I I OG I OG I OG

(GC)10 OG OG I OG I OG I P

(AT)10 S S I OG I OG I OG

FAD OG S I P I OG I I

NADP S S I P I I I OG

Note: U: ultrasound; P: precipitate; S: solution; I: insoluble; OG: opaque gel; TG: transparent gel; R. T.

room temperature.

21

Table S5 The subsequent and gradual gelation pathways for selective recognition of DNA

and DNA analogues and photos of these gels.

order

AMP ADP ATP st-DNA

(GC)1

0

(AT)10

FAD NADP

1 Zn(II)(TEG)(C6H11

O7)2 S

2 Zn(II)(TEG)SO4

3 Zn(II)(TEG)(NO3)2

S

4 Zn(II)(TEG)(AcO)2

5 Zn(II)(TEG)F2S

6 Zn(II)(TEG)I2

7 Zn(II)(TEG)Cl2

S

8 Zn(II)(TEG)Br2

Table S6 The gelation properties of Zn2+ complexes in the presence of different kinds of

ds-DNA.

Zn(II)(TEG)F2 Zn(II)(TEG)Cl2 Zn(II)(TEG)Br2 Zn(II)(TEG)I2

R.T. U R.T. U R.T. U R.T. U

stDNA OG I I OG I OG I OG

hsDNA S OG I OG I OG I I

ctDNA Sa I I I I I I I

Note: U: ultrasound; P: precipitate; S: solution; I: insoluble; OG: opaque gel; TG: transparent gel; R. T.

room temperature. a: Zn(II)(TEG)F2 was soluble and DNA was insoluble.

22

a b c

Figure S26 CLSM images of MCF-7 cells incubated for 30 min at 37 °C in PBS buffer (10

μM) of Zn(II)(TEG)I2. a) The bright image; b) The dark image for Zn(II)(TEG)I2, (λex=405

nm, emission collected: 500-600 nm); c) The overlay image of a) and b).

a b c

Figure S27 Fluorescent CLSM images of MCF-7 cells incubated for 30 min at 37 °C in tris

buffer (10 μM) of Zn(II)(TE)I2. (a) Bright field; b) The dark image for Zn(II)(TE)I2,

(λex=405 nm, emission collected: 500-600 nm); c) The overlay image of a) and b).

0 5 10 15 20 250

20

40

60

80

100

Via

bilit

y(%

)

C M)

Zn(II)(TEG)I2

Figure S28 Cell viability value (%) of Zn(II)(TEG)I2 by the MTT method.

23

0 5 10 15 20 250

20

40

60

80

100

Via

bilit

y(%

)

C M)

Zn(II)(TE)I2

Figure S29 Cell viability value (%) of Zn(II)(TE)I2 by the MTT method.

a

c

b

d

Figure S30 The co-stained experiments of Zn(II)(TEG)I2 with DAPI. MCF-7 cells

were incubated for 30 min at 37 °C with 1 in PBS buffer (10 μm) of Zn(II)(TEG)I2,

24

and then the cells were stained with DAPI for 30 min. a) The bright image; b) The

dark image for Zn(II)(TEG)I2, (λex=405 nm, emission collected: 500-600 nm); c) The

dark image for DAPI, (λex =405 nm, emission collected: 450-490 nm); d) The overlay

image of a), b), and c).

References[1] X. Piao, Y. Zou, J. C. Wu, T. Yi, Org. Lett. 2009, 11, 3818-3821.

[2] L. J. Geng, Y. J. Li, Z.Y. Wang, Y. Q. Wang, G. L Feng, X. L. Pang, X. D. Yu,

Soft Matter 2015, 11, 8100-8104.