Supporting Information
Capillary Electrophoresis coupled to Contactless Conductivity
Detection for the Analysis of S-Nitrosothiols Decomposition and
Reactivity
Abdulghani Ismail, Fanny d’Orlyé, Sophie Griveau, Fethi Bedioui, Anne Varenne, and
José Alberto Fracassi da Silva
Table S1: pKa values of the different carboxylic and amine moieties of reduced (GSH) and
oxidized (GSSG) glutathione.
Reference
Residue
C-Glu
C-Ter
Cys
N-Ter
[1]
[2]
[3]
[4]
[5]
[6]
[7]
2.69
2.12
2.05
2.13
2.12
2.12
3.68
3.53
3.59
3.40
3.51
3.53
3.59
8.88
8.66
8.75
8.72
8.74
9.12
9.65
9.46
9.62
9.65
9.62
9.66
8.66
8.75
[1]
[2]
[8]
[9]
2.73
2.3
2.09
1.96
3.80
3.7
3.49
3.50
-
9.51
9.2
9.18
9.18
GSH
GSSG
[1] Vila-Vicosa, D., Teixeira, V. H., Santos, H. A. F., Machuqueiro, M., J. Phys. Chem. B 2013,
117, 7507-7517.
[2] Pirie, N. W., Pinhey, K. G., J. Biol. Chem. 1929, 84, 321-333.
[3] Li, N. C., Gawron, O., Bascuas, G., J. Am. Chem. Soc. 1954, 76, 225-229.
[4] Rabenstein, D. L., J. Am. Chem. Soc. 1973, 95, 2797-2803.
[5] Krezel, A., Bal, W., Org. Biomol. Chem. 2003, 1, 3885-3890.
[6] The Merck Index, 11th ed., Entry# 4369.
[7] Lange's Handbook of Chemistry, t. e., pp. 5-40.
[8] Kozlowski, H., Urbanska, J., Sovago, I., Varnagy, K., Kiss, A., Spychala, J., Cherifi, K.,
Polyhedron 1990, 9, 831-837.
[9] Noszal, B., Szakacs, Z., J. Phys. Chem. B 2003, 107, 5074-5080.
GSO2H
GSO3H
GSH
GSSG
GSNO
Figure S1
0.5 V
C4D Output (V)
(9)
(8)
(7)
(6)
(5)
(4)
(3)
(2)
A
(1)
1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5
Peak Area (V·min)
time (min)
0.030
0.028
0.026
0.024
0.022
0.020
0.018
0.016
0.014
0.012
0.010
0.008
0.006
0.004
0.002
0.000
GSNO
GSSG
B
0
10
20
30
40
50
60
70
80
Exposition time (min)
Study of decomposition of a GSNO sample induced by light. A) Electropherograms of
(1) 102 μM GSSG, (2) 77 μM GSH, (3-9) 1 mM GSNO (purity 66 % determined by
colorimetric detection at 336 nm using Ɛ=920 M-1 cm-1) after visible light
decomposition for (3) 0 min, (4) 1 min, (5) 2 min, (6) 4 min, (7) 10 min, (8) 15 min, and
(9) 75 min. B) GSNO and GSSG peak areas as function of time of exposition. All samples
where prepared in CHES (20 mM, adjusted to pH 9.0 with NaOH). Hydrodynamic
injection: 3s, 11 kPa; BGE: 20 mM CHES (adjusted to pH 10.0 with NaOH); Separation
voltage: +27 kV, Capillary: 47 cm (37 cm effective), id 75 μm. Detection: 600 kHz, 1.9
Vpp. Average capillary electric current was 37 A.
C4D Output (V)
(8)
GSO2H
GSO3H
GSH
GSSG
GSNO
Figure S2
0.6V
(7)
(6)
(5)
(4)
(3)
(2)
(1)
1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3
time (min)
Study of decomposition of a GSNO sample induced by heat. A) Electropherograms of
(1) 128 μM GSSG, (2) 84 μM GSH, (3-8) 1 mM GSNO (purity 66 % determined by
colorimetric detection at 336 nm using Ɛ=920 M-1 cm-1) after decomposition at 80 °C
for (3) 0 min, (4) 10 min, (5) 20 min, (6) 50 min, (7) 70 min, and (8) 108 min. All samples
where prepared in CHES (20 mM, adjusted to pH 9.0 with NaOH). Hydrodynamic
injection: 3s, 11 kPa; BGE: 20 mM CHES (adjusted to pH 10.0 with NaOH); Separation
voltage: +27 kV, Capillary: 47 cm (37 cm effective), id 75 μm. Detection: 600 kHz, 1.9
Vpp. Average capillary electric current was 37 A.