Peptide-induced hierarchical long-range order and photocatalytic activity of porphyrin assemblies

Article abstract of DOI:10.1002/anie.201409149

Long-range structural order and alignment over different scales are of key importance for the regulation of structure and functionality in biology. However, it remains a great challenge to engineer and assemble such complex functional synthetic systems with order over different length scales from simple biologically relevant molecules, such as peptides and porphyrins. Herein we describe the successful introduction of hierarchical long-range order in dipeptide-adjusted porphyrin self-assembly by a thermodynamically driven self-orienting assembly pathway associated with multiple weak interactions. The long-range order and alignment of fiber bundles induced new properties, including anisotropic birefringence, a large Stokes shift, amplified chirality, and excellent photostability as well as sustainable photocatalytic activity. We also demonstrate that the aligned fiber bundles are able to induce the epitaxially oriented growth of Pt nanowires in a photocatalytic reaction.

Full text of DOI:10.1002/anie.201409149

Angewandte
Chemie
DOI: 10.1002/anie.201409149
Ordered Porphyrin Assemblies
Peptide-Induced Hierarchical Long-Range Order and Photocatalytic
Activity of Porphyrin Assemblies**
Kai Liu, Ruirui Xing, Chengjun Chen, Guizhi Shen, Linyin Yan, Qianli Zou, Guanghui Ma,
Helmuth Mçhwald, and Xuehai Yan*
Abstract: Long-range structural order and alignment over
different scales are of key importance for the regulation of
structure and functionality in biology. However, it remains
a great challenge to engineer and assemble such complex
functional synthetic systems with order over different length
scales from simple biologically relevant molecules, such as
peptides and porphyrins. Herein we describe the successful
introduction of hierarchical long-range order in dipeptide-
adjusted porphyrin self-assembly by a thermodynamically
driven self-orienting assembly pathway associated with multi-
ple weak interactions. The long-range order and alignment of
fiber bundles induced new properties, including anisotropic
birefringence, a large Stokes shift, amplified chirality, and
excellent photostability as well as sustainable photocatalytic
activity. We also demonstrate that the aligned fiber bundles are
able to induce the epitaxially oriented growth of Pt nanowires
in a photocatalytic reaction.
order structures and materials. Over the past decade,
significant progress has been made, and a number of
fascinating nanostructures, such as nanotubes, vesicles,
micelles, nanofibers, and nanorods, have been synthesized
by the self-assembly of molecular building blocks, including
peptides and proteins.[3] These well-defined nanostructures
could be considered as an assembly of molecules into
supramolecular systems at the nanoscale.
However, a great challenge remains to design and create
complex functional systems analogous to biological systems,
with long-range alignment of molecules over different scales
in a hierarchically organized manner in aqueous media. The
bundling and orientation of nanoscale substructures pre-
formed from molecular building blocks (such as actin
filaments and microtubules, which are ubiquitous in living
cells) regulate cellular events, including mitosis, substance
transport, and signal transduction.[4] That is, long-range
structural order beyond the nanoscale is essential in biological
systems for regulating structure and enabling functionality.
Therefore, processes for the creation of hierarchical long-
range structural order of biologically relevant molecules (such
as peptides and porphyrins) by self-assembly and insight into
the organization mechanisms are of crucial importance for
directing the construction of complex synthetic systems with
multiple functional properties. We report herein the discovery
of a self-orienting assembly pathway in the solution phase that
leads porphyrin J-aggregates to form fiber bundles that are
highly aligned over long distances owing to the peptide-
mediated adjustment of intermolecular synergistic interac-
tions in association with electrostatic, p–p, hydrogen-bonding
and van der Waals forces.
One of the key types of naturally occurring biomolecules
are porphyrins, a main component of light-harvesting systems
in both photosynthetic bacteria and green plants.[5] In
a biological setting, porphyrin molecules function as a result
of their organization by means of peptides or proteins and
other molecules, but not individually.[6] In this study, the
highly ordered organization and concomitant long-range
alignment of the negatively charged porphyrin molecule
(tetrakis(4-sulfonatophenyl)porphine (H2TPPS; see Fig-
ure S1 in the Supporting Information)[7] was induced by
a simple positively charged dipeptide (l-Lys-l-Lys, KK; see
Figure S1) through tuned self-assembly in solution. We
demonstrate that nanorod-shaped J-aggregates, formed pref-
erentially by strong p–p interactions of H2TPPS molecules,
spontaneously group into aligned fiber bundles, presumably
as a result of the compromise between long-range electro-
static repulsion and short-range van der Waals attraction. The
bundled fibers are anisotropically aligned and show amplified
S
elf-assembly is ubiquitous at various length scales through-
out biology and is a key process of life. Structural complexity
in biological systems stems from the hierarchically ordered
organization of molecular elements (such as amino acids,
peptides, proteins, lipids, and nucleic acids) on the basis of
intermolecular noncovalent interactions, including electro-
static, hydrogen-bonding, p–p, van der Waals, and hydro-
phobic interactions.[1,2] Inspired largely by biological systems,
bottom-up self-assembly has been developed as an elegant
strategy for the synthesis of a rich variety of functional high-
[*] Dr. K. Liu, R. Xing, Dr. C. Chen, Dr. G. Shen, Dr. L. Yan, Dr. Q. Zou,
Prof. Dr. G. H. Ma, Prof. Dr. X. Yan
National Key Laboratory of Biochemical Engineering
Institute of Process Engineering, Chinese Academy of Sciences
100190 Beijing (China)
E-mail: yanxh@ipe.ac.cn
Homepage: http://www.yan-assembly.org/
Dr. K. Liu
University of Chinese Academy of Sciences
Beijing 100049 (China)
Dr. G. Shen, Prof. Dr. H. Mçhwald
Max Planck Institute of Colloids and Interfaces
Am Mꢀhlenberg 1, 14476 Potsdam/Golm (Germany)
[**] We acknowledge financial support from the National Nature
Science Foundation of China (Project Nos. 21473208, 81402871,
and 51403214), the Talent Fund of the Recruitment Program of
Global Youth Experts, the Chinese Academy of Sciences (CAS), and
CAS visiting professorships for senior international scientists
(Project No. 2013T2G0037) as well as the German Max Planck
Society. The first two authors contributed equally to this work.
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/anie.201409149.
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chirality, a large Stokes shift, and excellent photostability.
Significantly, the bundling and long-range alignment of
nanoscale J-aggregates support sustainable photocatalytic
reactions and remain stable against photodegradation, in
contrast to individual H2TPPS J-aggregates. This finding will
enable the self-assembly of sophisticated functional systems
with hierarchically organized structures over different scales
in the solution phase through the tuning of intermolecular
synergistic interactions and could potentially extend the range
of robust structures and functional properties known for these
materials.
We observed the immediate appearance of visible green
aggregates as negatively charged H2TPPS was mixed with
positively charged KK at a final pH value smaller than 2 in an
aqueous solution. Scanning electron microscopy (SEM) and
transmission electron microscopy (TEM) showed that the
aggregates were long fiber bundles consisting of orientation-
ally aligned nanorod and/or nanofiber substructures (Fig-
ure 1a,b; see also Figure S2). The fiber bundles had widths of
several micrometers and lengths of tens of micrometers (up to
These hierarchically organized structures of photosynthetic
molecules are reminiscent of complex functional systems in
biology, such as the natural light-harvesting antennae (chlor-
osomes) of green sulfur bacteria, which are a typical class of
photosynthetic bacteria living in deep oceans.[9] The chlor-
osomes are an ensemble of light-harvesting pigments with
hierarchically organized structures featuring long-range align-
ment. These structures enable efficient light harvesting and
offer protection from photodegradation. Higher-level order
of photosynthetic porphyrin assemblies possibly leads to the
amplification of characteristic spectroscopic signatures and
improvement of the corresponding photocatalytic activity.
J-Aggregates of H2TPPS molecules have a UV/Vis
absorption spectrum with a strongly red shifted Soret band
at 490 nm (J-band) as compared to that of H2TPPS mono-
mers, and a second band at 705 nm (Q-band; Figure 2a).
H2TPPS monomers have corresponding absorptions at 434
and 645 nm (see Figure S3).[10] The fiber bundles showed
a spectroscopic signature similar to that of J-aggregates alone,
but with apparent broadening of both the Soret band and the
Q-band. This result indicates interactions between KK
dipeptides and H2TPPS. The spectral broadening is probably
caused by the change in polarity around the assembled
porphyrins in the presence of positively charged dipeptides.[11]
The Fourier transform infrared (FTIR) spectrum of the
H2TPPS J-aggregates showed strong bands at 1226 and
1192 cmÀ1, which are attributed to the vibrations of SO3
À
groups. These bands shifted to 1221 and 1181 cmÀ1, respec-
tively, in the case of the fiber bundles (see Figure S4). This
shift indicates strong interactions between KK dipeptides and
H2TPPS, presumably as a result of hydrogen bonding and
electrostatic interactions. Circular dichroism (CD) spectro-
scopic analysis showed that the fiber bundles had a strongly
split Cotton effect with positive and negative signals at 486
and 493 nm, respectively, and the signal intensity was 10 times
that observed for individual J-aggregates (Figure 2b).[7] This
result indicates that the chiral signature of organized por-
phyrins is dramatically amplified as a result of peptide-
induced hierarchical long-range alignment. Time-dependent
CD spectra gave in-depth insight into structure formation and
evolution (see Figure S5). It was found that the CD peaks in
the first 5 min after H2TPPS was mixed with KK were ill-
defined, after 15 min they became normal, and the intensity of
the chiral signal increased markedly over time. This observa-
tion suggests a dipeptide-induced growth of J-aggregates
associated with the charge screening of H2TPPS, which in turn
promotes helical packing in the peptide–porphyrin nanorods/
nanofibers. The ill-defined chiral signature implies initially
incomplete formation of J-aggregates, presumably owing to
the strong interactions between KK and H2TPPS monomers
or oligomers, thus influencing the ordered stacking of
H2TPPS units in the helices. Nevertheless, assembly into
a helical-packing arrangement predominates over time, and J-
aggregate nanorods ultimately form through dynamic regu-
lation by balancing electrostatic, hydrogen-bonding, and p–p
interactions. The nanoscale substructures further self-assem-
ble to form fiber bundles with long-range order, as evidenced
by signal amplification in the CD spectrum and microscopic
observations.
Figure 1. a) TEM image of bundled fibers. b) Magnified TEM image of
the fibers, showing aligned substructures at long range. c) AFM
contact-mode height image of bundled fibers (the top value on the
scale is 200 nm; the bottom value is 0 nm). d) Magnified AFM
amplitude image of a single fiber showing the long-range order of
aligned nanorods or nanofibers along the longitudinal axis.
hundreds of micrometers). This observed structure is rather
different from the organized structure of H2TPPS J-aggre-
gates, which are well known to form nanorods and nano-
ribbons with a typical width and length of 20–30 nm and
several micrometers,[8] respectively, as also confirmed by SEM
(see Figure S2b). Atomic force microscopy (AFM) of the
surface of single fiber bundles confirmed the presence of
aligned nanorods and nanofibers of tens of nanometers in
diameter along the long axis of the fiber bundles (Fig-
ure 1c,d), in agreement with the SEM and TEM observation.
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the fiber bundles when they were
located between crossed polarizers
(Figure 2e,f). This result indicates
that the order extends from the
molecular level to the nanoscale and
even to the microscale within the
hierarchically organized fiber bun-
dles. Birefringence extinction at the
cross-point of two orthogonal fiber
bundles observed by polarized mi-
croscopy indicates the uniform distri-
bution of aligned nanorods/nanofib-
ers in each.
On the basis of these results, we
are able to suggest a mechanism for
the formation of fiber bundles
(Figure 3). Nanorods consisting of J-
aggregates are initially formed as
a consequence of dipeptide-mediated
charge screening of porphyrin J-
aggregates in combination with
hydrogen-bonding and p-stacking
interactions. The induction of J-aggre-
gate formation by cationic KK was
further confirmed by the following
control experiments. It is well-known
that H2TPPS can generally form J-
aggregates at pH < 2.[12] In the present
case, the fiber bundles were exclu-
sively observed at a pH values higher
than 3.9 (see Figure S6), thus indicat-
ing the dominant role of cationic KK
in triggering the onset of J-aggregate
formation and facilitating the subse-
quent assembly of fiber bundles. By
contrast, shorter fibers similar to
H2TPPS J-aggregates were formed
when the hydrophobic naphthalene-
modified dilysine H-Lys-Lys-bNA
(KK-bNA; see Figure S1) was used
instead of KK for coassembly (see
Figure S7), because the hydrophobic
group naphthalene to some extent
engages in p-stacking with porphyrin
molecules, thus influencing the long-
range order based on p–p stacking
and hydrogen bonding. The formed
nanorods spontaneously align at long
range, presumably by a self-orienting
Figure 2. a) UV/Vis absorption spectra of J-aggregates (stacked H2TPPS) formed at pH 1.9 and
fiber bundles self-assembled through the electrostatic coupling of cationic KK and anionic H2TPPS.
b) CD spectra of H2TPPS J-aggregates and fiber bundles showing a strongly split Cotton effect and
a 10-fold higher signal intensity of the fiber bundles relative to that of the J-aggregates. c) Confocal
image of fiber bundles showing red photoluminescence. The fiber sample was excited at 488 nm
and the emitted fluorescence collected from 680 to 760 nm. d) Fluorescence spectrum of peptide–
porphyrin fiber bundles showing an emission maximum at 720 nm. The sample was excited at
488 nm. e) Birefringence of fiber bundles between crossed polarizers. This effect suggests an
ordered alignment along the longitudinal axis. f) Extinction of anisotropic photoluminescence (as
denoted by arrows) at the cross-points of orthogonal fiber bundles under crossed polarizers. This
effect indicates a uniform distribution of aligned substructures in each fiber.
Confocal fluorescence microscopy images showed red
fluorescence of fiber bundles upon excitation at 488 nm that is
attributable to the presence of porphyrins within the fiber
bundles (Figure 2c). The fluorescence spectrum of the fiber
bundles showed an emission maximum at 720 nm (excitation
at 488 nm; Figure 2d). This result is consistent with the
observation of red fluorescence by confocal fluorescence
microscopy. Apparently, the bundling leads to a large Stokes
shift of more than 200 nm. This Stokes shift may enhance
photostability. Strong birefringence was observed throughout
assembly process due to the competition of rotational and
translational entropy in terms of Onsager theory.[13] The rapid
growth and formation of nanorods leads to a high local
concentration of nanorods, thus promoting orientation and
alignment at long range. In the absence of dipeptides, the
concentration of J-aggregate nanorods is relatively low, and
the nanorods can move freely in the diluted suspension
without restriction by neighboring nanorods, thus enabling
the random orientation of nanorods and maximizing the
rotational and translational entropy. In the case of the
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It is self-evident that the cata-
lytic accessible surface of the
fiber bundles is smaller than
that of J-aggregate nanorods
(AFM images) for the same
porphyrin concentration, thus
explaining why the reaction
rate with fiber bundles is
lower in the initial stage of the
reaction. However, pure J-
aggregates are not stable
enough against photodegrada-
tion, thus leading to a decay in
photocatalytic activity with
time. In contrast, the higher-
level organization of fiber bun-
dles enables more efficient
Figure 3. Proposed mechanism for the formation of fiber bundles at long range: Nanorods consisting of J-
aggregates are initially formed as a consequence of the dipeptide-mediated charge screening of porphyrin
J-aggregates in combination with hydrogen-bonding and p-stacking interactions. The formed nanorods
spontaneously align at long range, presumably by a self-orienting assembly process due to competition
between long-range electrostatic repulsion and short-range van der Waals attraction.
resistance
against
light
damage, as evidenced by the
dipeptide-induced formation of fiber bun-
dles, the nanorods grow rapidly and are
confined in a limited space; their transla-
tional freedom is limited. The total entropy is
maximized through the alignment of the
nanorods: The translational entropy is
increased by sacrificing the orientational
entropy.
The ordered alignment of nanorods into
higher-level superstructures (bundles) is
astonishing and of key importance for
improving the functional properties of such
materials, such as photocatalytic activity and
photostability. For the first proof-of-concept
study, we compared the light-induced oxida-
tion of iodide to triiodide in the presence of
fiber bundles and individual J-aggregates.
The bands at l = 353 and 287 nm in the UV/
Vis absorption spectra correspond to the
characteristic absorption of triiodide,[6b,14] the
time-dependent production of which can be
used to monitor the reaction rate related to
photocatalytic activity (Figure 4a). The pho-
tocatalytic oxidation reaction was supported
in the presence of the fiber bundles, as
confirmed by the increase in the peak
intensities at l = 353 nm and 287 nm. The
absorption intensity at l = 353 nm was plot-
ted as a function of time to study the kinetic
evolution of triiodide (Figure 4b). In com-
parison to the use of individual J-aggregates,
the reaction rate with the fiber bundles is
Figure 4. a) UV/Vis absorption spectra quantifying the photocatalytic synthesis of triiodide
by fiber bundles and showing time-dependent changes in the peak intensities at
l=353 nm and 287 nm (initial iodide concentration is 5 mm). b) Plots of absorption
intensity (l=353 nm) versus irradiation time for triiodide production in the presence of
fiber bundles or H2TPPS J-aggregates. c,d) TEM images of Pt nanowires and nanospheres
synthesized in situ in the presence of fiber bundles by a photocatalytic pathway.
rather low at the beginning of the reaction,
but increases more rapidly after 2 h and
retains the rising tendency with time. The
lower reaction rate at the beginning may be
attributed to the higher-level assembly of
dipeptide-mediated porphyrin J-aggregates. e,f) Magnified TEM images of a Pt nanowire and nanosphere surrounding the nanowire.
4
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negligible change in peak intensity of both the Soret band and
the Q-band. Hence, the higher-order organization of dipep-
tide-induced porphyrin supramolecular stacking is probably
responsible for the enhanced photocatalytic performance.
Their photocatalytic properties make the hierarchically
organized fiber bundles a most suitable photocatalytic
template for the in situ synthesis of functional metal nano-
particles with high potential for a broad range of applications.
Therefore, we investigated the feasibility of the use of
peptide–porphyrin fiber bundles to capture visible light for
the photocatalytic synthesis of PtNPs in the presence of
ascorbic acid as an electron donor (Figure 4c–f; see also
Figure S8). It was evident that Pt nanospheres with a diameter
of 100–200 nm or nanowires of around 200 nm in length and
10 nm in width were formed locally on the fiber bundles.
Magnified TEM images indicated that both nanospheres and
nanowires comprised individual nanoparticles of approxi-
mately 2 nm in size (Figure 4c,d). Control experiments with-
out light irradiation or in the absence of the fiber bundles
showed no production of such Pt nanostructures, thus
indicating that the photocatalytic process takes place in the
presence of the fiber bundles. These results suggest that
porphyrins within the fiber bundles efficiently capture light to
yield photoexcited states that are rapidly reduced by ascorbic
acid (electron donor). The resulting porphyrin radical anion
has rather strong reduction capability. Thus, metal salts are
catalytically reduced to the metallic state through a succession
of light-harvesting and photochemical cycles.[15] The growth of
Pt nanospheres appears to be directly related to the nano-
wires that were commonly observed if the concentration of Pt
salts or the aging time was reduced (see Figure S9). Appa-
rently, the nanospheres prefer to grow around the nanowires
(Figure 4e), presumably as a result of further growth through
an autocatalytic reduction process.[15b] Surprisingly, the Pt
nanowires were exclusively oriented along the longitudinal
axis of the fiber bundles and had a uniform diameter, thus
suggesting an epitaxial growth mechanism along the texture
of the aligned fibers. The formation of nanowires most likely
follows a photocatalytic reduction mechanism, as the nano-
wires consist of relatively discrete PtNPs with size of about
2 nm (Figure 4 f). Overall, photosynthetic fiber bundles can
serve as biotemplates for directing the synthesis of functional
metal nanostructures through a predominantly photocatalytic
reduction mechanism. In particular, the hierarchical long-
range alignment within the fiber bundles induces the epitaxial
growth and orientation of Pt nanowires.
bundles support sustainable photocatalytic reactions and
perform better than isolated porphyrin J-aggregates. The
long-range alignment induces the unique epitaxially oriented
growth of Pt nanowires (ultimately into Pt nanospheres)
consisting of discrete Pt nanoparticles of 2 nm in size in
a photocatalytic process. The coassembly of biologically
relevant small molecules, such as dipeptides and photosensi-
tized dyes, into superstructures with long-range order and
insight into their organization mechanism will offer a refer-
ence for the design and engineering of biomimetic multifunc-
tional complex systems from simple molecular building
blocks. Furthermore, our findings unravel the potential of
the long-range alignment of fibers into bundles for the design
of molecular materials and devices with new functions and
properties.
Received: September 16, 2014
Revised: October 7, 2014
Published online: && &&, &&&&
Keywords: fiber bundles · hierarchical long-range order ·
.
peptides · porphyrinoids · self-assembly
[1] a) J.-M. Lehn, Proc. Natl. Acad. Sci. USA 2002, 99, 4763 – 4768;
b) G. M. Whitesides, B. Grzybowski, Science 2002, 295, 2418 –
2421; c) T. Aida, E. W. Meijer, S. I. Stupp, Science 2012, 335,
813 – 817; d) P. A. Korevaar, S. J. George, A. J. Markvoort,
M. M. J. Smulders, P. A. J. Hilbers, A. P. H. J. Schenning,
T. F. A. De Greef, E. W. Meijer, Nature 2012, 481, 492 – 496;
e) S. F. M. van Dongen, S. Cantekin, J. A. A. W. Elemans, A. E.
Rowan, R. J. M. Nolte, Chem. Soc. Rev. 2014, 43, 99 – 122; f) Y. S.
Xie, M. Akada, J. P. Hill, Q. M. Ji, R. Charveta, K. Ariga, Chem.
Commun. 2011, 47, 2285 – 2287; g) M. Li, S. Ishihara, Q. Ji, M.
Akada, J. P. Hill, K. Ariga, Sci. Technol. Adv. Mater. 2012, 13,
053001.
[2] a) J. B. Li, Q. He, X. H. Yan, Molecular Assembly of Biomimetic
Systems, Wiley, Hoboken, 2011; b) S. Mann, Acc. Chem. Res.
2012, 45, 2131 – 2141; c) Q. L. Zou, L. Zhang, X. H. Yan, A. H.
Wang, G. H. Ma, J. L. Li, H. Mçhwald, S. Mann, Angew. Chem.
Int. Ed. 2014, 53, 2366 – 2370; Angew. Chem. 2014, 126, 2398 –
2402; d) F. F. Zhao, G. Z. Shen, C. J. Chen, R. R. Xing, Q. L.
Zou, G. H. Ma, X. H. Yan, Chem. Eur. J. 2014, 20, 6880 – 6887.
[3] a) K. Ariga, Q. M. Ji, T. Mori, M. Naito, Y. Yamauchi, H. Abe,
J. P. Hill, Chem. Soc. Rev. 2013, 42, 6322 – 6345; b) M. A.
Kostiainen, O. Kasyutich, J. J. L. M. Cornelissen, R. J. M.
Nolte, Nat. Chem. 2010, 2, 394 – 399; c) R. V. Ulijn, D. N.
Woolfson, Chem. Soc. Rev. 2010, 39, 3349 – 3350, and references
therein; d) X. H. Yan, P. L. Zhu, J. B. Li, Chem. Soc. Rev. 2010,
39, 1877 – 1890; e) X. H. Yan, J. B. Li, H. Mçhwald, Adv. Mater.
2011, 23, 2796 – 2801; f) X. H. Yan, Y. Su, J. B. Li, J. Frꢀh, H.
Mçhwald, Angew. Chem. Int. Ed. 2011, 50, 11186 – 11191;
Angew. Chem. 2011, 123, 11382 – 11387; g) L. Adler-Abramovi-
cha, E. Gazit, Chem. Soc. Rev. 2014, DOI: 10.1039/c4s00164h;
h) S. G. Zhang, Nat. Biotechnol. 2003, 21, 1171 – 1178.
In conclusion, we have demonstrated that the dipeptide-
adjusted self-assembly of porphyrin molecules can lead to the
highly ordered organization and long-range alignment of
nanorod-shaped porphyrin J-aggregates. Competitive multi-
ple weak interactions, such as electrostatic, p–p, hydrogen-
bonding, and van der Waals interactions, are responsible for
the hierarchical organization and order at different length
scales. We propose a self-orienting assembly pathway as
described by Onsager theory for the formation of the fiber
bundles. The hierarchical long-range alignment into fiber
bundles introduces the new properties of anisotropic bire-
fringence, a large Stokes shift, amplified helicity, and excel-
lent photostability. We have also demonstrated that the fiber
[4] a) D. J. Needleman, M. A. Ojeda-Lopez, U. Raviv, H. P. Miller,
L. Wilson, C. R. Safinya, Proc. Natl. Acad. Sci. USA 2004, 101,
16099 – 16103; b) H. G. Cui, E. T. Pashuck, Y. S. Velichko, S. J.
Weigand, A. G. Cheetham, C. J. Newcomb, S. I. Stupp, Science
2010, 327, 555 – 559; c) S. Zhang, M. A. Greenfield, A. Mata,
L. C. Palmer, R. Bitton, J. R. Mantei, C. Aparicio, M. O.
de La Cruz, S. I. Stupp, Nat. Mater. 2010, 9, 594 – 601.
[5] a) C. M. Drain, A. Varotto, I. Radivojevic, Chem. Rev. 2009, 109,
1630 – 1658; b) F. Wꢀrthner, T. E. Kaiser, C. R. Saha-Mçller,
Angew. Chem. Int. Ed. 2014, 53, 1 – 7
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5
These are not the final page numbers!

.
Angewandte
Communications
Angew. Chem. Int. Ed. 2011, 50, 3376 – 3410; Angew. Chem.
2011, 123, 3436 – 3473; c) T. Silviu Balaban, Acc. Chem. Res.
2005, 38, 612 – 623.
Czaja, A. B. Tripathi, Precambrian Res. 2007, 158, 141 – 155; c) S.
Mann, Angew. Chem. Int. Ed. 2013, 52, 155 – 162; Angew. Chem.
2013, 125, 166 – 173.
[6] a) D. E. Wagner, C. L. Phillips, W. M. Ali, G. E. Nybakken, E. D.
Crawford, A. D. Schwab, W. F. Smith, R. Fairman, Proc. Natl.
Acad. Sci. USA 2005, 102, 12656 – 12661; b) S. Frꢀhbeißer, F.
Grçhn, J. Am. Chem. Soc. 2012, 134, 14267 – 14270; c) B. C.
Kovaric, B. Kokona, A. D. Schwab, M. A. Twomey, J. C.
de Paula, R. Fairman, J. Am. Chem. Soc. 2006, 128, 4166 – 4167.
[7] J. M. Ribꢁ, J. Crusats, F. Saguꢂs, J. Claret, R. Rubires, Science
2001, 292, 2063 – 2066.
[8] a) O. Ohno, Y. Kaizu, H. Kobayashi, J. Chem. Phys. 1993, 99,
4128 – 4139; b) L. Zhang, M. H. Liu, J. Phys. Chem. B 2009, 113,
14015 – 14020; c) A. D. Schwab, D. E. Smith, C. S. Rich, E. R.
Young, W. F. Smith, J. C. de Paula, J. Phys. Chem. B 2003, 107,
11339 – 11345.
[10] a) E. B. Fleischer, J. M. Palmer, T. Srivastava, A. Chatterjee, J.
Am. Chem. Soc. 1971, 93, 3162 – 3167; b) R. F. Pasternack, P. R.
Huber, P. Boyd, G. Engasser, L. Francesconi, E. Gibbs, P. Fasella,
G. Cerio Venturo, L. d. Hinds, J. Am. Chem. Soc. 1972, 94, 4511 –
4517; c) B. J. Pepe-Mooney, B. Kokona, R. Fairman, Biomacro-
molecules 2011, 12, 4196 – 4203.
[11] D. Mauzerall, Biochemistry 1965, 4, 1801 – 1810.
[12] B. Kokona, A. M. Kim, R. C. Roden, J. P. Daniels, B. J. Pepe-
Mooney, B. C. Kovaric, J. C. de Paula, K. A. Johnson, R. Fair-
man, Biomacromolecules 2009, 10, 1454 – 1459.
[13] L. Onsager, Ann. N. Y. Acad. Sci. 1949, 51, 627 – 659.
ˇ
[14] L. Slavetꢃnskꢄ, J. Mosinger, P. Kubꢄt, J. Photochem. Photobiol. A
2008, 195, 1 – 9.
[9] a) S. Ganapathy, G. T. Oostergetel, P. K. Wawrzyniak, M. Reus,
A. Gomez Maqueo Chew, F. Buda, E. J. Boekema, D. A. Bryant,
A. R. Holzwarth, H. J. M. de Groot, Proc. Natl. Acad. Sci. USA
2009, 106, 8525 – 8530; b) J. W. Schopf, A. B. Kudryavtsev, A. D.
[15] a) J. Song, Y. Yang, C. J. Medforth, E. Pereira, A. K. Singh, H. F.
Xu, Y. B. Jiang, C. J. Brinker, F. van Swol, J. A. Shelnutt, J. Am.
Chem. Soc. 2004, 126, 635 – 645; b) Z. C. Wang, C. J. Medforth,
J. A. Shelnutt, J. Am. Chem. Soc. 2004, 126, 16720 – 16721.
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ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2014, 53, 1 – 7
These are not the final page numbers!

Angewandte
Chemie
Communications
Ordered Porphyrin Assemblies
Get organized, be effective! Dipeptide-
adjusted porphyrin self-assembly resulted
in the formation of fiber bundles with
hierarchical long-range order by a ther-
modynamically driven pathway based on
the competitive interplay of multiple weak
interactions (see picture). The long-range
alignment of the fibers led to anisotropic
birefringence, a large Stokes shift, ampli-
fied chirality, excellent photostability, and
sustainable photocatalytic activity.
K. Liu, R. Xing, C. Chen, G. Shen, L. Yan,
Q. Zou, G. H. Ma, H. Mçhwald,
X. Yan*
&&&& — &&&&
Peptide-Induced Hierarchical Long-
Range Order and Photocatalytic Activity
of Porphyrin Assemblies
Angew. Chem. Int. Ed. 2014, 53, 1 – 7
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
7
These are not the final page numbers!