Orthogonal photo-switching of supramolecular patterned surfaces

Article abstract of DOI:10.1039/c8cc00770e

We used Azo/α-CD and ipAzo/γ-CD host-guest complexes to demonstrate that four independent stable states can be orthogonally photo-switched by UV (365 nm), blue (470 nm), green (530 nm) and red light (625 nm). A supramolecular patterned surface was fabrica

Full text of DOI:10.1039/c8cc00770e

View Article Online
View Journal
ChemComm
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: D. Wang, F.
Schellenberger, J. Pham, H. Butt and S. Wu, Chem. Commun., 2018, DOI: 10.1039/C8CC00770E.
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Volume 52 Number
1 4 January 2016 Pages 1–216
ChemComm
Accepted Manuscripts are published online shortly after
Chemical Communications
www.rsc.org/chemcomm
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1359-7345
COMMUNICATION
Marilyn M. Olmstead, Alan L. Balch, Josep M. Poblet, Luis Echegoyenet al.
Reactivity differences of Sc3N@C2n (2n 68 and 80). Synthesis of the
first methanofullerene derivatives of Sc N@D5h-C80
=
3
rsc.li/chemcomm

Page 1 of 5
ChemComm
View Article Online
DOI: 10.1039/C8CC00770E
TOC
Four independent states are orthogonally photo-controlled and switched by ultraviolet,
blue, green and red light irradiations on micropatterned surfaces.

Please doChneomt Cadomjumst margins
Page 2 of 5
View Article Online
DOI: 10.1039/C8CC00770E
Journal Name
COMMUNICATION
Orthogonal Photo-switching of Supramolecular Patterned
Surfaces
Dongsheng Wang,a Frank Schellenberger, b Jonathan T. Pham,c Hans-Jürgen Butt,b and Si Wu*b
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
www.rsc.org/
We used Azo/α-CD and ipAzo/γ-CD host-guest complexes to limited to only two functional states (“on” and “off”), and are
demonstrate that four independent stable states can be insufficient for functioning in an environment with a complex
orthogonally photo-switched by UV (365 nm), blue (470 nm), green range of light stimuli. On the other hand, orthogonal photo-
(530 nm) and red light (625 nm). A supramolecular patterned controllable systems possess a “mode dial”-type property that
surface was fabricated and orthogonally photo-switched by light can switch between ≥3 states under control of ≥3 lights with
with different wavelengths.
different wavelengths. However, most photoresponsive
chromophores have heavily overlapped absorption in the
ultraviolet (UV)-visible region, which is one of the biggest
challenges in the advancement of photoresponsive orthogonal
systems [3e, 5].
Orthogonal switching can be used to control multiple functions
within a single material system by two or more independent
external stimuli (e.g., pH, heat, light and chemical) [1]. In
contrast to traditional stimuli-responsive systems, which are
switched between two states, orthogonal systems can be
triggered into three or more states having a wider range of
possible functions [1a, 2]. However, the reported orthogonal
switchable systems are controlled by stimuli with different
types (i.e., light/heat [1a, 1c], pH/chemical [1b] and
heat/chemical [1d, 1e]), and the research on orthogonal
switching systems by one-type of stimulus remains an unsolved
challenge.
Light has been widely used to control processes and
functions in chemistry and material science as an external
stimulus because it can be applied with high spatial and time
resolution [3]. Photoresponsive materials have been
successfully applied in the fields of biomedicine, nanoscience,
hydrogels, and surfaces [3b, 3d, 4]. Typically, chromophores
responsive to light are integrated in the material systems, which
can be switched between two independent states upon light
exposure, and hence can display two different functions.
However, these “switch”-type photoresponsive materials are
Azobenzene (Azo) and cyclodextrin (CD) have been
extensively investigated for designing photoresponsive
supramolecular materials [6]. Under dark or visible light
irradiation, trans Azo can enter the hydrophobic cavity of α-CD
to form a strong 1:1 host-guest complex. Under UV light
irradiation (~365 nm), trans Azo switches to cis form, and the
host-guest complex dissociates due to hydrophilicity of the cis
Azo and unfitted molecular scale with the α-CD cavity [6]. In our
previous work, we synthesized tetra-ortho-isopropoxy-
substituted Azo (ipAzo), which shows trans-to-cis isomerization
under green or red light irradiation (530 or 625 nm), and cis-to-
trans isomerization under heating, UV or blue light irradiation
(365 or 470 nm). cis ipAzo forms a 1:1 host-guest complex with
γ-CD, while the host-guest interaction between trans ipAzo and
γ-CD is weak [7]. The result is the reverse of Azo/α-CD complex.
Here, we combined ipAzo/γ-CD with the Azo/α-CD host-
guest complex to fabricate photo-switchable supramolecular
micropatterned surfaces.
4 states can be orthogonally
controlled by UV, blue, green and red light. Patterned surfaces
are important for a number of fields related to materials and
nano science [8]. In particular, photoresponsive patterned
surfaces can be fabricated with switchable wettability,
morphology, and functions under precise control of external
light irradiation [9]. This makes the photoresponsive patterned
surfaces applicable in molecular motors and cell culture [10].
However, till now, studies on orthogonal photo-switching of
micro/nano-patterned surfaces are lacking that develop the
a.School of Optoelectronic Science and Engineering of UESTC, University of
Electronic Science and Technology of China, No. 4, Section 2, North Jianshe Road,
610054, Chengdu, China.
b.Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz,
Germany. E-mail: wusi@mpip-mainz.mpg.de
c. Department of Chemical and Materials Engineering, University of Kentucky, 177
F. Paul Anderson Tower, Lexington, KY, USA 40506.
† Footnotes relating to the title and/or authors should appear here.
Electronic Supplementary Information (ESI) available: [details of any supplementary
information available should be included here]. See DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Page 3 of 5
Please doChneomt Cadomjumst margins
View Article Online
DOI: 10.1039/C8CC00770E
Journal Name
COMMUNICATION
Scheme 1. Schematic illustration of photoresponsive orthogonal supramolecular micropatterned surface. 4 independent states on surface could be obtained and
switched under controlling of UV, blue, green and red light irradiations.
surfaces to be intelligent and applicable in complex light with red light at 625 nm triggers trans-to-cis isomerization of
environments. Herein, we show that 4 independent states of ipAzo, while Azo is not significantly affected (Figure S6). This
Azo/CD micropatterns are achievable by simply irradiating the might be attributed to the slightly higher absorbance of trans
surface with light of different wavelengths (Scheme 1):
ipAzo than cis ipAzo in red light region (Figure 1a) [7, 11]. A
1. “Azo” state: trans Azo/trans ipAzo, trans Azo/α-CD on summary of the photoisomerization of Azo and ipAzo under the
surface;
different light irradiations is presented in Table 1.
2. “On” state: trans Azo/cis ipAzo, trans Azo/α-CD and cis
ipAzo/γ-CD on surface;
3. “Off” state: cis Azo/trans ipAzo, no complex on surface;
4. “ipAzo” state: cis Azo/cis ipAzo, cis ipAzo/γ-CD on surface.
The orthogonally photo-controlled isomerization of
The Azo/ipAzo combination can therefore be orthogonally
controlled by light with various wavelengths, which was
demonstrated by H NMR. Azo-Si and ipAzo-Si with the same
1
concentrations in DMSO-d6 was used during the investigation
(Figure 1b). After blue light irradiation, the Azo/ipAzo system
Azo/ipAzo was investigated by UV/vis spectroscopy and 1H was in the photostationary trans Azo/trans ipAzo state with
nuclear magnetic resonance (NMR) spectroscopy (Figure 1). approximately 100% and 96% of trans Azo and trans ipAzo,
Azo-Si and ipAzo-Si were used as the model molecules and respectively (integral of 1H NMR spectra). Green light irradiation
dissolved together (see Supporting Information (SI), Scheme transformed the system to the trans Azo/cis ipAzo while UV
S1). Our results demonstrated that Azo and ipAzo isomerization light irradiation transformed it to the cis Azo/trans ipAzo. Each
can be triggered in different directions by 4 light irradiations of these photostationary states are easily obtained from any of
(Table 1). UV light at 365 nm excites the π-π* transition of trans the others by application of blue light (trans Azo/trans ipAzo),
Azo and triggers a trans-to-cis isomerization, inducing a sharp green light (trans Azo/cis ipAzo), and UV light (cis Azo/trans
decrease of the π-π* transition band and an increase of the n- ipAzo). On the other hand, the fourth state (cis Azo/cis ipAzo)
π* transition band (Figure 1a, Figure S3a). In contrast, the trans- can only
to-cis isomerization of ipAzo under UV light irradiation is
minimal. Only ~25% of trans ipAzo switched to the cis form after
UV light irradiation (Figure S3b). Irradiation with blue light at
470 nm excites the n-π* transition and induces a cis-to-trans
isomerization for both Azo and ipAzo (Figure S4). Green light
(530 nm) induces a cis-to-trans isomerization for Azo, and trans-
to-cis isomerization for ipAzo (Figure S5). Moreover, irradiation
Table 1. Photoisomerization of Azo and ipAzo under UV light, blue light, green light and
red light irradiations.
UV light
trans-to-cis a
cis-to-trans
Blue light
cis-to-trans
cis-to-trans
Green light
cis-to-trans
trans-to-cis
Red light
Not affected
trans-to-cis
Azo
ipAzo
a. Text in bold and green indicates the photostationary state under the light
irradiation.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 2
Please do not adjust margins

ChemComm
Please do not adjust margins
Page 4 of 5
Journal Name
COMMUNICATION
the Glass-Azo surface. This is driven by theVietwraArnticsl-etOon-lcinies
photoisomerization of Azo, as described DinOTI:a10b.l1e0319,/Cre8sCuCl0ti0n7g70inE
the dissociation of the host-guest complex, and further release
of α-CD-FITC from the surface. The green fluorescent micro-
stripes could be visible again on Glass-Azo surface by blue light
irradiation and further treating with the α-CD-FITC aqueous
solution (Figure S10a, S11, see detail in SI). As suggested by
Table 1, the Glass-ipAzo could be controlled by green and blue
light irradiation in an opposite manner (Figure S10b). To
demonstrate this, a red fluorescent dye, rhodamine B (RhB),
was modified with γ-CD to obtain γ-CD-RhB (Scheme S2, SI).
Upon immersing the Glass-ipAzo substrate in a γ-CD-RhB
aqueous solution in the dark, no fluorescent micro-stripes are
visible due to the weak host-guest interaction between trans
ipAzo and γ-CD-RhB. By irradiating the Glass-ipAzo substrate
with green light and further treating with the γ-CD-RhB aqueous
solution, 2D fluorescent micro-stripes become visible. This is
attributed to the green light induced trans-to-cis isomerization
of ipAzo on the surface (Table 1). While cis ipAzo shows a strong
host-guest interaction with γ-CD, the γ-CD-RhB could be
visualized on Glass-ipAzo surface. Furthermore, by irradiating
the surface with blue light, the fluorescent micro-stripes can be
erased (Figure S10b, S12, see detail in SI).
The Azo/α-CD and ipAzo/γ-CD host-guest complexes have
been demonstrated to be orthogonal in our previous work [7].
Considering that the Azo/ipAzo system can be controlled by
different light wavelengths to 4 different photostationary
states, we demonstrated
micropatterned surface using the Glass-ipAzo/Azo crossed
micro-stripes described above (Scheme S3).
a photoresponsive orthogonal
Figure 1. (a) UV/vis spectra of Azo and ipAzo ([Azo-Si]=[ipAzo-Si]=0.25 mM in
dimethyl sulfoxide (DMSO)): trans Azo and trans ipAzo were obtained after
heating at 60oC for 1 h in dark, absorbance of trans Azo at λ=351 nm and trans
ipAzo at λ=310 nm were normalized; the UV/vis spectra of cis Azo and cis ipAzo
were obtained from calculation (see detail in SI). (b) 1H NMR spectra of Azo/ipAzo
under UV, blue, green and red light irradiations ([Azo-Si]=[ipAzo-Si]=1.5 mM in
DMSO-d6, 300 MHz at 298K. UV, blue and green light=30 min, red light=20 min.).
A mixed aqueous solution of α-CD-FITC and γ-CD-RhB (1:1,
in molar ratio) was used for the orthogonal photo-switching
process of Glass-ipAzo/Azo. The green fluorescent FITC and red
fluorescent RhB can be monitored independently using
different channels by confocal microscopy (SI). The Glass-
ipAzo/Azo substrate surface was marked by a diamond cutter to
make sure that the orthogonal photo-switching process
occurred in-situ. Under blue light irradiation, the Glass-
ipAzo/Azo surface is in the “Azo” state (Scheme 1). Fluorescent
be achieved by starting with the cis Azo/trans ipAzo and
irradiating with red light, which is reversible upon UV light
irradiation (Figure 1b). The results obtained by 1H NMR are
consistent with our UV/vis data and Table 1
.
To fabricate photoresponsive orthogonal micropatterned
surfaces, Azo-Si and ipAzo-Si were micro-contact printed onto a
glass surface (Scheme S3). A polydimethylsiloxane (PDMS)
stamp with 3-μm wide stripes and 5-μm wide valleys was used
for the micropattern preparation (Figure S9). Azo and ipAzo
micro-stripes were immobilized on glass surfaces by printing,
which are denoted as Glass-Azo and Glass-ipAzo, respectively
(see detail in SI). The Glass-ipAzo was used to further prepare a
photoresponsive orthogonal micropatterned surface, which is
denoted as Glass-ipAzo/Azo. To prepare this pattern, an Azo-Si
coated PDMS stamp was rotated by 90o and then stamped onto
the Glass-ipAzo surface, which leads to a crossed grid of
Azo/ipAzo micro-stripe structures (Scheme S3).
To visualize the microstructures, a green fluorescent dye,
fluorescein isothiocyanate (FITC), was used to modify α-CD to
obtain α-CD-FITC (Scheme S2, SI). The 2D fluorescent micro-
stripes could be imaged by confocal microscopy on the Glass-
Azo substrate after introducing an aqueous solution of α-CD-
FITC, due to the formation of a host-guest complex between
trans Azo and α-CD-FITC (Figure S10a). Irradiation by UV light
leads to the disappearance of the fluorescent micro-stripes on
Figure 2. Confocal microscopic images of Glass-ipAzo/Azo after treating with UV,
blue, green and red light irradiations. Scale bar: 30 μm.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Page 5 of 5
ChemComm
COMMUNICATION
Journal Name
Barner-Kowollik, Macromolecules 2017, 50, 538V5i-e5w3A9rt1ic.le(Odn)liYne.
Liu, L, Shangguan, H. Wang, D. Xia andDBO.IS: h10i,.1P0o39ly/mC8.CCCh0e0m77.0E
micro-stripes are therefore visible in the FITC channel after
treating with the α-CD-FITC/γ-CD-RhB mixture (Figure 2, S13).
Green light irradiation switched the Glass-ipAzo/Azo to the
“On” state, both α-CD-FITC and γ-CD-RhB are thus immobilized
on the substrate surface, and a crossed FITC/RhB micro-stripe
structure is observed. Upon UV light irradiation, the Glass-
ipAzo/Azo is transformed to the “Off” state, neither α-CD-FITC
nor γ-CD-RhB are immobilized on the substrate surface.
Therefore, no fluorescent micro-stripes are visible on the
surface (Figure S13). Each of these states is easily obtained from
any of the others by the application of blue light (“Azo” State,
FITC micro-stripes), green light (“On” State, crossed FITC/RhB
micro-stripes), or UV light (“Off” State, no micro-stripes)
2017,
8
, 3783-3787; (e) X. Wu, Y. Yu, L. Gao, X. Hu and L.
, 966-970; (f) F. Rachdi, L.
Wang, Org. Chem. Front. 2016,
3
Hajji, C. Goze, D. J. Jones, P. Maireles-Torres and J. Rozière,
Solid. State. Commun. 1996, 100, 237-240.
2
3
(a) W. Xu, P. A. Ledin, Z. Iatridi, C. Tsitsilianis and V. V.
Tsukruk, Angew. Chem. Int. Ed. 2016, 55, 4908-4913; (b) C. Y.
Ang, S. Y. Tan, S. Wu, Q. Qu, M. F. E. Wong, Z. Luo, P. Li, S. T.
Selvan and Y. Zhao, J. Mater. Chem. C 2016, 4, 2761-2774.
(a) H. M. D. Bandara and S. C. Burdette, Chem. Soc. Rev.
2012, 41, 1809-1825; (b) M. M. Russew and S. Hecht, Adv.
Mater. 2010, 22, 3348-3360; (c) K. Ichimura, S. K. Oh and M.
Nakagawa, Science 2000, 288, 1624-1626; (d) W. A. Velema,
W. Szymanski and B. L. Feringa, J. Am. Chem. Soc. 2014, 136
2178-2191; (e) F. Ercole, T. P. Davis and R. A. Evans, Polym.
,
(Scheme 1, Figure 2), which are as expected by our UV/vis and
Chem. 2010, 1, 37-54; (f) J. Lv, Y. Liu, J. Wei, E. Chen, L. Qin
NMR results. The fourth state (“ipAzo” State) is only obtained
by irradiating the Glass-ipAzo/Azo substrate with UV light and
red light in sequence; then the γ-CD-RhB is immobilized on the
surface and fluorescent micro-stripes are only visible in the RhB
channel (Figure 2, S13). UV light irradiation induces the back
switching from the “ipAzo” state to the “Off” state. This
demonstrates that the supramolecular micropatterned system,
formed by the Azo/α-CD and ipAzo/γ-CD, can be photo-
controlled orthogonally by UV light, blue light, green light and
red light irradiation, and switched between 4 different states
and Y. Yu, Nature 2016, 537, 179-184; (g) S. Sun, D.
Thompson, U. Schmidt, D. Graham and G. J. Leggett, Chem.
Commun. 2010, 46, 5292-5294; (h) C. Wu, Q. Cheng, S. Sun
and B. Han, Carbon 2012, 50, 1083-1089.
(a) D. P. Ferris, Y. L. Zhao, N. M. Khashab, H. A. Khatib, J. F.
Stoddart and J. I. Zink, J. Am. Chem. Soc. 2009, 131, 1686-
1688; (b) N. Fomina, J. Sankaranarayanan and A. Almutairi,
Adv. Drug. Delivery. Rev. 2012, 64, 1005-1020; (c) I. Tomatsu,
K. Peng and A. Kros, Adv. Drug. Delivery. Rev. 2011, 63, 1257-
1266; (d) J. Deng, X. Liu, W. Shi, C. Cheng, C. He and C. Zhao,
4
ACS Macro. Lett. 2014,
3
, 1130-1133; (e) M. Chen and F.
, 1549-1555.
Besenbacher, ACS Nano. 2011,
5
(Scheme 1, Figure 2).
5
6
(a) M. Natali and S. Giordani, Chem. Soc. Rev. 2012, 41, 4010-
4029; (b) A. S. Lubbe, W. Szymanski and B. L. Feringa, Chem.
Sov. Rev. 2017, 46, 1052-1079.
In summary, we demonstrated orthogonal switching of an
Azo/ipAzo system under pure photo-control by UV (365 nm),
blue (470 nm), green (530 nm) and red light (625 nm)
irradiation. 4 independent photostationary states of Azo/ipAzo
combinations are realized and switched between each other by
(a) A. Harada, Y. Takashima and M. Nakahata, Acc. Chem.
Res. 2014, 47, 2128-2140; (b) L. Yang, X. Tan, Z. Wang and X.
Zhang, Chem. Rev. 2015, 115, 7196-7239; (c) S. Yagai and A.
Kitamura, Chem. Soc. Rev. 2008, 37, 1520-1529. (d) G. Yu, K.
Jie and F. Huang, Chem. Rev. 2015, 115, 7240-7303; (e) D.
light.
A
photoresponsive orthogonal supramolecular
Wang, D. Xie, W. Shi, S. Sun and C. Zhao, Langmuir 2013, 29
,
micropatterned surface was fabricated by combining the Azo/α-
CD host-guest complex with ipAzo/γ-CD. The successful design
of photoresponsive orthogonal supramolecular systems offers
more applications of light-controlled materials in complex
irradiation environments. Although the reported structures are
in the microscopic scale, we envision that photoresponsive
orthogonal supramolecular systems should also be applicable to
macroscopic systems. For example, Shi et al. proposed a novel
methodology of macroscopic supramolecular assembly to
fabricate 3D ordered structures [12]. This method can mildly
load necessary bioactive species to designated locations within
the structure during fabrication, which is significant for the
increasing demand in constructing chemically or biologically
specific tissue scaffolds. Our design may lead to more intelligent
photoresponsive microscopic and macroscopic systems in the
future.
8311-8319; (f) Y. Zhou, D. Wang, S. Huang, G. Auernhammer,
Y. He, H.-J. Butt and S. Wu, Chem. Commun. 2015, 51, 2725-
2727.
7
8
D. Wang, M. Wagner, A. K. Saydjari, J. Mueller, S. Winzen, H.-
J. Butt and S. Wu, Chem. Eur. J. 2017, 23, 2628-2634.
(a) D. Chanda, K. Shigeta, S. Gupta, T. Cain, A. Carlson, A.
Mihi, A. J. Baca, G. R. Bogart, P. Braun and J. A. Rogers, Nat.
Nanotechnol. 2011, 6, 402-407; (b) S. Park, D. H. Lee and T. P.
Russell, Adv. Mater. 2010, 22, 1882-1884; (c) J. Rodríguez-
Hernández, Prog. Polym. Sci. 2015, 42, 1-41; (d) M. Jaschke
and H.-J. Butt, Langmuir, 1995, 11, 1061-1064.
9
(a) W. Jiang, G. Wang, Y. He, X. Wang, Y. An, Y. Song and L.
Jiang, Chem. Commun. 2005, 3550-3552; (b) H. Zhou, C. Xue,
P. Weis, Y. Suzuki, S. Huang, K. Koynov, G. K. Auernhammer,
R. Berger, H.-J. Butt and S. Wu, Nat. Chem. 2017, 9, 145-151;
(c) A. A. Brown, O. Azzaroni and W. T. S. Huck, Langmuir
2009, 25, 1744-1749.
10 (a) Y. Wang and Q. Li, Adv. Mater. 2012, 24, 1926-1945; (b) Y.
Gong, J. Yang, F. Cao, J. Zhang, H. Cheng, R. Zhuo and X.
D.W. was supported by the CSC program. This work was
supported by the Deutsche Forschungsgemeinschaft (DFG, WU
787/2-1).
Zhang, J. Mater. Chem. B 2013, 1, 2013-2017; (c) Z. Ming, X.
Ruan, C. Bao, Q. Lin, Y. Yang and L. Zhu, Adv. Funct. Mater.
2017, 27, 1606258.
11 (a) D. Wang and S. Wu, Langmuir 2016, 32, 632-636; (b) D.
Wang, M. Wagner, H.-J. Butt and S. Wu, Soft. Matter. 2015,
11, 7656-7662.
12 M. Cheng, Y. Wang, L. Yu, H. Su, W. Han, Z. Lin, J. Li, H. Hao,
C. Tong, X. Li and F. Shi, Adv. Funct. Mat. 2015, 25, 6851-
6857.
Notes and references
1
(a) M. M. Lerch, M. J. Hansen, W. A. Velema, W. Szymanski
and B. L. Feringa, Nat. Commun. 2016, 7, 12054; (b) S.
Schoder and C. A. Schalley, Chem. Commun. 2017, 53, 9546-
9549; (c) J. Steinkoenig, M. M. Zieger, H. Mutlu and C.
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins