Dynamic light scattering (DLS) studies
Kluwer Academic Publishers, Dordrecht, 1999, p. 11; (b) B. Ke,
Photosynthesis, Kluwer Academic Publishers, Dordrecht, 2001.
2 (a) M. Calvin, Acc. Chem. Res., 1978, 11, 369; (b) M. Calvin, Energy
Res., 1979, 3, 73; (c) T. Meyer, Acc. Chem. Res., 1989, 22, 163; (d) D.
Gust, T. A. Moore and A. L. Moore, Acc. Chem. Res., 2001, 34, 40;
Vesicle solutions were prepared as described above. DLS measure-
ments were made on a Honeywell Microtac UPA-150 at room
temperature. The mean refractive index of 1.81 was used as the
refractive index of the sample. The mean diameters of particles
were calculated from volume distribution data obtained as the
average of five measurements.
(
e) D. Gust, T. A. Moore and A. L. Moore, in Aritificial Photosyn-
thesis, ed. A. F. Collings and C. Critchley, Wiley, Weinheim, 2005,
p. 187.
3
(a) A. D. Bangham, Prog. Biophys. Mol. Biol., 1968, 18, 29; (b) D. W.
Deamer and P. S. Uster, in Liposomes, ed. M. J. Ostro, Marcel Dekker,
New York, 1983, p. 27.
4
5
W. E. Ford, J. W. Otvos and M. Calvin, Nature, 1978, 274, 507.
For reviews of electron transfer across membranes, see: (a) J. N.
Robinson and D. Cole-Hamilton, Chem. Soc. Rev., 1991, 20, 49; (b) S. V.
Lymar, V. N. Parmon and K. I. Zamaraev, Top. Curr. Chem., 1991, 159,
Photochemistry
A vesicle solution was placed into a quartz cell (10 mm × 10 mm),
and Ar was bubbled into the solution for 60 min. The solution
was irradiated with a 500 W xenon arc lamp through both a
Toshiba optical cutoff filter (UV-35, >350 nm) and a band pass
1
.
6 L. Zhu, R. F. Khairutdinov, J. L. Cape and J. K. Hurst, J. Am. Chem.
Soc., 2006, 108, 825.
+
•
7 T. Katagi, T. Yamamura, T. Saito and Y. Sasaki, Chem. Lett., 1981,
filter (UV-D36B, 360 ± 20 nm). The MV accumulation was
1
451.
monitored by an increase in the absorption at 604 nm, and the
8
A. A. Krasnovsky, A. N. Semenova and V. V. Nikandrov, Photobiochem.
Photobiophys., 1982, 4, 227.
+
•
+•
concentration of MV , [MV ], was calculated by using its molar
−
1
−1 4,28
9 (a) S. Murata, R. Nakatsuji and H. Tomioka, J. Chem. Soc., Perkin
Trans. 2, 1995, 793; (b) S. Ikeda, S. Murata, K. Ishii and H. Hamaguchi,
Bull. Chem. Soc. Jpn., 2000, 73, 2783.
10 For a preliminary report, see: A. Yoshida, A. Harada, T. Mizushima
and S. Murata, Chem. Lett., 2003, 32, 68.
1 For the calclulation of the free-energy change for the total redox
extinction coefficient (e = 12 400 M cm ).
In the electron
transport in the presence of surfactant, 27 lM of Triton X-100
(
(
Tokyo Kasei Kogyo Co., Ltd.) was added to the vesicle solution
3 mL) before irradiation. The concentration of Asc , [Asc ],
−
−
1
was determined as follows: the irradiated vesicle solution was
reaction, +0.09 V and −0.46 V were employed for the redox potentials
+
•
aerated to oxidize MV , and an aqueous solution of Triton X-100
10% (w/w), 100 lL) was added to the solution. After stirring for
•
−
12a
2+
+•12b
of Asc /Asc (pH 7.0) and MV /MV
(vs. SCE), respectively.
(
12 (a) D. Njus and P. M. Kelly, Biochim. Biophys. Acta, 1993, 1144,
2
35; (b) S. L. Murov, I. Carmichael and G. L. Hug, Handbook of
5
min, a K
3
[Fe(CN)
6
] solution (30 mM) in 1.0 M Tris–HCl buffer
−
Photochemistry, 2nd edn, Marcel Dekker, New York, 1993.
containing 1.0 M NaCl was added, and [Asc ] was calculated
on the basis of the consumption of [Fe(CN)
1
3 (a) M. Aikawa, N. J. Turro and K. Ishiguro, Chem. Phys. Lett., 1994,
3
−
6
]
determined by a
2
22, 197; (b) L. Li and L. K. Patterson, Photochem. Photobiol., 1995,
−
1
−1
decrease in the absorption of 420 nm (e = 1027 M cm ). In the
62, 51.
+
•
14 (a) Y. Barenholz, T. Cohen, R. Korenstein and M. Ottolenghi,
Biophys. J., 1991, 59, 110; (b) Y. Barenholz, T. Cohen, E. Haas and
M. Ottolenghi, J. Biol. Chem., 1996, 271, 3085; (c) S. J. Webb, K.
Greenaway, M. Bayati and L. Trembleau, Org. Biomol. Chem., 2006, 4,
experiment for dependence of the initial rate of MV formation on
light intensity, the vesicle solution was divided into four portions
(
3 mL each), and each solution was irradiated with 366 nm light
2
399.
emitted by an extra-high pressure mercury lamp (Ushio, SX-
UI D500HAMP) through both an optical cutoff filter (UV-35,
1
5 (a) H. Schomburg, H. Staerk and A. Weller, Chem. Phys. Lett., 1973,
2
2, 1; (b) Y. Hirata, T. Saito and N. Mataga, J. Phys. Chem., 1987, 91,
119; (c) X. Liu, K.-K. Iu and J. K. Thomas, Chem. Phys. Lett., 1993,
>
350 nm) and a band-path filter (UV-D36B, 360 ± 20 nm). The
3
light intensity was regulated by using four Toshiba neutral density
filters, the transmittances of which for 366 nm light are 23.0, 12.5,
204, 163.
1
6 The irradiation of the vesicle solution with the shorter wavelength light
2+
causes direct excitation of MV having an intense transition with a
6
.6, and 3.8%.
maximum at 259 nm (log e = 4.2 in Tris–HCl buffer, pH 7.5) and weak
+
•
tailing to ca. 350 nm, which leads to the MV formation even in the
absence of the sensitizer.
Fluorescence quenching studies
2+
1
1
7 It was reported that a long-lived reduced MV derivative was produced
by the irradiation of a lipid functionalized pyrene in vesicles even
in the absence of an electron donor, which is probably due to the
scavenging of the pyrene radical cation by the double bond of lipid
A vesicle solution for fluorescence quenching studies was prepared
in the same manner as that described above, except for using 1.0 M
NaCl instead of AscNa. Solutions of the sensitizer containing
various amounts of quenchers were placedinquartzcells (10mm ×
13
molecules. .
8 In the case of the irradiation using (1-pyrenyl)methylamine (2a) as a
+
•
sensitizer, ca. 30% of MV was accumulated even in the absence of
1
0 mm). Fluorescence spectra were measured at room temperature
−
Asc , which is probably due to an irreversible electron donation of the
under air on excitation at 350 nm. Relative fluorescence intensities
/F) were determined by measuring the peak of heights for
amino group of 2a (Fig. S3†).
(
F
0
19 (a) D. C. Dong and M. A. Winnik, Photochem. Photobiol., 1982, 35,
1
2
7; (b) D. C. Dong and M. A. Winnik, Can. J. Chem., 1984, 62,
560.
the maxima. The fluorescence lifetime was measured by using a
pulsed Q-switch Nd:YAG laser (SOLAR LF114) as the excitation
source. The fluorescence decay profiles were recorded by the use of
third harmonic generation of the laser that provided UV pulses at
2
2
0 J. Luisetti, H. M o¨ hwald and H.-J. Galla, Biochim. Biophys. Acta, 1979,
552, 519.
+
•
1 The quantum yield for MV
pyrenyl)methylamine (2a) in the vesicle solution was determined to be
.10 using a photon counting meter (Ushio, UIT-150) under irradiation
formation sensitized by (1-
3
55 nm with a duration of 13 ns. A sample solution was placed in
0
a quartz cell (10 mm × 10 mm), and the fluorescence was collected
with 366 nm light of a 500 W extra-high-pressure mercury lamp (Ushio,
SX-UI D500HAMP). Thus, in the tables, the relative quantum yields
◦
10
at 90 to the excitation light.
+
•
for MV formation, U
2 S. C. Wallace, M. Gr a¨ tzel and J. K. Thomas, Chem. Phys. Lett., 1973,
3, 359.
3 D. Rehm and A. Weller, Isr. J. Chem., 1970, 8, 259.
t
(rel), are represented using 2a as a standard.
2
2
2
References
1
(a) J. Whitmarsh and Govindjee, in Concepts in Photobiology, ed.
G. S. Singhal, G. Renger, S. K. Sopory, K.-D. Irrgang and Govindjee,
24 For the calculation of the free-energy change for the photoinduced
electron transfer, +1.16 V, −2.09 V, and 76.7 kcal mol− were employed
1
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