Supporting Information
Reductive and Oxidative DNA Dama
ge by Photoactive Platinum(II)
Intercalators
Wei Lu, David A. Vicic and Jacqueline K. Barton*
Division of Chemistry and Chemical Engineer
ing, California Institute of Technology,
Pasadena, CA 91125
Supporting Information Available:
Scheme depicting the synthesis of the
ligand, glassy emission spectra, CIF file and
structural parameters of crystal structure
of
2
·(DMF)
3
·(H
2
O)
2
, additional figures of the UV-vis traces of Pt(II) complexes upon
DNA titration and HPLC traces for photoreactions with
Cp
C, d
Cp
G and DNAs. This
material is available free of charge via the Internet at
http://pubs.acs.org
.
S
2
N
N
O
O
N
N
N
N
N
N
N
N
CN
CN
KOH
EtOH
NC
CN
H
2
N
NH
2
EtOH
CN
PPh
3
PPh
3
2 Br
N
N
CH
2
Cl
2
, LiOH
NH
2
NH
2
N
N
H
2
SO
4
As
2
O
5
CHO
dppz
CN
2
-np
CN-np
np
bp
CH
3
CN, DBU
NH
NH
Scheme S1
Ligand Synthesis
S
3
500
600
700
800
0
2
4
6
8
10
12
14
Intensity
λ
/ nm
[(dppz)Pt(mes')
2
]
2+
(
1
)
500
600
700
800
0
10
20
30
40
Intensity
λ
/ nm
[(np)Pt(mes')
2
]
2+
(
2
)
600
700
800
0
2
4
6
8
10
12
Intensity
λ
/ nm
[(CN-np)Pt(mes')
2
]
2+
(
3
)
500
600
700
800
0
20
40
60
80
Intensity
λ
/ nm
[(bp)Pt(mes')
2
]
2+
(
5
)
Figure S1
Emission spectra of complex
1
–
3
and
5
in 10 M LiCl at 77 K,
λ
ex
=
370 nm, concentration ~ 5
×
10
–5
M.
S
4
270
370
470
0.0
0.2
0.4
0.6
0.8
1.0
0
500
1000
1500
0.05
0.10
0.15
0.20
Absorbance / A. U.
λ
/ nm
286 nm
Absorbance @ 370 nm
[DNA] /
μ
M
Figure S2
Absorption traces of the titration of a 20-mer DNA into a 20 μM
[(np)Pt(mes’)
2
]Cl
2
(
2
) in a buffer of 20 mM sodium phosphate and 50 mM NaCl, pH
7.0. Inset: Plot of the absorbance at 370 nm against the amount of DNA added.
270
370
470
0.0
0.2
0.4
0.6
0.8
0
500
1000
1500
0.05
0.10
0.15
0.20
0.25
Absorbance / A. U.
λ
/ nm
270 nm
Absorbance @ 370 nm
[DNA] /
μ
M
Figure S3
Absorption traces of the titration
of a 20-mer DNA into a 20 μM [(CN-
np)Pt(mes’)
2
]Cl
2
(
3
) in a buffer of 20 mM sodium phosphate and 50 mM NaCl, pH
7.0. Inset: Plot of the absorbance at 370 nm against the amount of DNA added.
S
5
300
400
500
0.0
0.2
0.4
0.6
0.8
Absorbance / A. U.
λ
/ nm
318 nm
Figure S4
Absorption traces of the titration of a 20-mer DNA into a 20 μM
[(CN
2
-np)Pt(mes’)
2
]Cl
2
(
4
) in a buffer of 20 mM sodium phosphate and 50 mM NaCl,
pH 7.0.
300
400
500
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Absorbance / A. U.
λ
/ nm
Figure S5
Absorption traces of the titration of a 20-mer DNA into a 20 μM
[(bp)Pt(mes’)
2
]Cl
2
(
5
) in a buffer of 20 mM sodium phosphate and 50 mM NaCl, pH
7.0.
S
6
550
600
650
700
0
1
2
3
4
λ
ex
= 270 nm (isobestic point)
Emission Intensity
λ
/ nm
DNA 20-mer
0
660
792
924
1056
1188
1320
1452
1584
1716
1848
μ
M
~615 nm
~665 nm
Vibronic Progression ~1200 cm
-1
Figure S6
Emission traces of the titration of a 20-mer DNA into a 20 μM [(CN-
np)Pt(mes’)
2
]Cl
2
(
3
) in a buffer of 20 mM sodium phosphate and 50 mM NaCl, pH
7.0.
5101520
Absorbance @ 260 nm
Irradiation time
C
Hp
C
Cp
C
60 min
45 min
30 min
20 min
10 min
0 min
Retention time / min
Figure S7
HPLC traces for photoreaction of
Cp
C nucleoside in the presence of
[(CN-np)Pt(mes’)2]
2+
complex. Conditions: 30
μ
L aliquot, 500
μ
M
Cp
C; 500
μ
M
Pt(II) complex; 50 mM NaCl; 20 mM NaP buffer; pH 7.0; 370 nm (~12.5 mW).
S
7
5 1015202530
Absorbance @ 260 nm
Irradiation time
dG
d
Hp
G
d
Cp
G
20 min
12 min
8 min
5 min
2 min
0 min
Retention time / min
Figure S8
HPLC traces for photoreaction of
Cp
C nucleoside in the presence of
[(np)Pt(mes’)2]
2+
complex. Conditions: 30
μ
L aliquot, 20
μ
M
Cp
C; 20
μ
M Pt(II)
complex; 50 mM NaCl; 20 mM NaP buffer; pH 7.0; 370 nm (~12.5 mW).
S
8
3480
3500
3520
N
O
O
Signal Intensity
Gauss
Pt, DNA, h
ν
, O
2
Pt, h
ν
, O
2
DNA, h
ν
, O
2
Pt, DNA, O
2
Pt, DNA, h
ν
Figure S9
EPR spectra of the mixtures of complex
1
and TEMP. General
conditions: 150
μ
L aliquot; 20 mM TEMP; 500
μ
M [(dppz)Pt(Mes’)
2
]
2+
; 20
μ
M DNA
where applicable; 50 mM NaCl; 20 mM NaP buffer; pH 6.99; room temperature; 370
nm (~8 mW) irradiation 10 min where a
pplicable; three freeze-pump-thaw cycles
where applicable; X-band EPR spectra were obtained on a Bruker EMX spectrometer
equipped with a rectangular cavity working in the TE
102
mode; EPR parameters:
receiver gain = 1
×
10
4
, modulation amplitude = 2 G, microwave power = 10 mW, 5
scans.
S
9
51015
A
T
60 min
45 min
30 min
20 min
Retention time / min
dark
10 min
C
G
Absorbance @ 275 nm
0 102030405060
70
80
90
100
G/C
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Figure S10
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
G
/
C
and 50
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the presence of
O
2
.
S
10
5101520
Cp
C
5 min
A
T
60 min
45 min
30 min
20 min
Retention time / min
dark
10 min
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
G/
Cp
C
Irradiation time / min
C
G
A
Cp
C
Figure S11
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
G
/
Cp
C
and 50
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the presence
of O
2
.
S
11
0
5
10
15
20
25
A
T
Cp
C
12 min
5 min
4 min
3 min
2 min
Retention time / min
dark
1 min
Cp
G
C
G
Hp
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
120
% Nucleoside remaining versus T
Cp
G/
Cp
C + O
2
Irradiation time / min
C
G
A
Cp
C
Cp
G
Figure S12
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
Cp
G
/
Cp
C
and 50
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the
presence of O
2
.
S
12
0
5
10
15
20
25
12 min
A
T
Cp
C
5 min
4 min
3 min
2 min
Retention time / min
dark
1 min
Cp
G
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
Irradiation time / min
Cp
G
Cp
C
G
C
A
Figure S13
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
Cp
G
/
Cp
C
and 50
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in D
2
O in the presence
of O
2
.
S
13
0
5
10
15
20
25
A
T
Cp
C
12 min
5 min
4 min
3 min
2 min
Retention time / min
dark
1 min
Cp
G
C
G
Hp
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
120
% Nucleoside remaining versus T
Cp
G/
Cp
C
-
O
2
Irradiation time / min
Cp
G
Cp
C
G
C
A
Figure S14
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
Cp
G
/
Cp
C
and 50
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the
absence of O
2
.
S
14
5101520
Cp
C
5 min
A
T
60 min
45 min
30 min
20 min
Retention time / min
dark
10 min
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Cp
C
G/
Cp
C
Figure S15
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
G
/
Cp
C
and 5
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the presence
of O
2
.
S
15
5101520
I
d
Cp
C
5 min
A
T
60 min
45 min
30 min
20 min
Retention time / min
dark
10 min
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Cp
C
I
I/
Cp
C
Figure S16
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
I
/
Cp
C
and 5
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the presence of
O
2
.
S
16
510152025
Cp
G
Cp
C
2 min
A
T
30 min
20 min
12 min
8 min
Retention time / min
dark
5 min
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Cp
C
Cp
G
Cp
G/
Cp
C
Figure S17
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
Cp
G
/
Cp
C
and 5
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the
presence of O
2
.
S
17
510152025
Cp
G
2 min
A
T
30 min
20 min
12 min
8 min
Retention time / min
dark
5 min
C
G
Absorbance @ 275 nm
0 102030405060
0
20
40
60
80
100
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Cp
G
Cp
G/C
Figure S18
HPLC traces of DNA base damages during the photoreaction of 5
μ
M
DNA duplex
Cp
G
/
C
and 5
μ
M [(dppz)Pt(mes’)
2
]
2+
complex in buffer in the presence
of O
2
.
S
18
0 102030405060
0
20
40
60
80
100
120
% Nucleoside remaining versus T
Irradiation time / min
C
G
A
Cp
C
Cp
G
Figure S19
Percent nucleoside remaining after photoreaction of 5
μ
M
[(bp)Pt(mes’)
2
]Cl
2
(
5)
and 5
μ
M duplex
Cp
G/
Cp
C
in the presence of O
2
, and after
nuclease digestion and HPLC analysis. For HPLC quantitation, T was used as internal
standard.
0 1020304050
0
20
40
60
80
100
120
% Nucleoside remaining versus T
Irradiation time / min
Cp
CG
G
C
A
Cp
G
Figure S20
Percent nucleoside remaining after photoreaction of 50
μ
M
[(bp)Pt(mes’)
2
]Cl
2
(
5)
and 5
μ
M duplex
Cp
G/
Cp
C
in the presence of O
2
, and after
nuclease digestion and HPLC analysis. For HPLC quantitation, T was used as internal
standard.