Sensitive fluorescent vesicles based on the supramolecular inclusion of β-cyclodextrins with N-alkylamino-L-anthraquinone

Article abstract of DOI:10.1080/10610278.2010.514614

Self-assembly fluorescent vesicles were designed and prepared based on the supramolecular interaction of cyclodextrins and N-alkylamino-L-anthraquinone (n-AQ). As the guest molecules, n-AQs with alkyl lengths ranging from C ₀ to C₁₈ were synthesised by the direct reaction of alkylamine with L-nitroanthraquinone in N,N-dimethylformamide. Transmission electron microscopy (TEM), scanning electron microscopy, dynamic light scattering and epi fluorescence microscopy were employed to study the vesicle system in detail. The formation mechanism of the vesicles was suggested based on the results of TEM observation, UV spectrum, fluorescence spectrum, ¹H NMR and simulation in the software Materials 4.3. The fluorescent vesicles show sensitive and multi-responsive properties to external stimuli. Based on these properties, we tried to use the vesicle as a new kind of fluorescence staining material for living cells. The vesicles can effectively stain the human breast cancer cells (MCF-7) and mice mononuclear macrophages (REW-264.7). This paper provides a better understanding in the design and preparation of drug delivery, biomaterials and intelligent materials.

Full text of DOI:10.1080/10610278.2010.514614

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Sensitive fluorescent vesicles based on the
supramolecular inclusion of β-cyclodextrins withN-
alkylamino-l-anthraquinone
Tao Sun a , Huacheng Zhang a , Hui Yan a , Jianye Li a , Guanghui Cheng b , Aiyou Hao a
Hongwei Qiao c & Feifei Xin a
,
a Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of
Chemistry and Chemical Engineering , Shandong University , Jinan , 250100 , P.R. China
b Department of Medical Genetics and Key Laboratory for Experimental Teratology, Ministry
of Education , Shandong University , Jinan , 250012 , P.R. China
c Shandong Shengquan Chemical Co., Ltd , Jinan , 250204 , P.R. China
Published online: 15 Apr 2011.
To cite this article: Tao Sun , Huacheng Zhang , Hui Yan , Jianye Li , Guanghui Cheng , Aiyou Hao , Hongwei Qiao & Feifei
Xin (2011) Sensitive fluorescent vesicles based on the supramolecular inclusion of β-cyclodextrins withN-alkylamino-l-
anthraquinone, Supramolecular Chemistry, 23:5, 351-364, DOI: 10.1080/10610278.2010.514614
To link to this article: http://dx.doi.org/10.1080/10610278.2010.514614
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Supramolecular Chemistry
Vol. 23, No. 5, May 2011, 351–364
Sensitive fluorescent vesicles based on the supramolecular inclusion of b-cyclodextrins with
N-alkylamino-L-anthraquinone
Tao Suna†, Huacheng Zhanga†, Hui Yana, Jianye Lia, Guanghui Chengb, Aiyou Haoa*, Hongwei Qiaoc and Feifei Xina
aKey Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong
University, Jinan 250100, P.R. China; bDepartment of Medical Genetics and Key Laboratory for Experimental Teratology, Ministry of
Education, Shandong University, Jinan 250012, P.R. China; Shandong Shengquan Chemical Co., Ltd, Jinan 250204, P.R. China
c
(Received 25 April 2010; final version received 28 July 2010)
Self-assembly fluorescent vesicles were designed and prepared based on the supramolecular interaction of cyclodextrins and
N-alkylamino-L-anthraquinone (n-AQ). As the guest molecules, n-AQs with alkyl lengths ranging from C0 to C18 were
synthesised by the direct reaction of alkylamine with L-nitroanthraquinone in N,N-dimethylformamide. Transmission
electron microscopy (TEM), scanning electron microscopy, dynamic light scattering and epi fluorescence microscopy were
employed to study the vesicle system in detail. The formation mechanism of the vesicles was suggested based on the results
1
of TEM observation, UV spectrum, fluorescence spectrum, H NMR and simulation in the software Materials 4.3. The
fluorescent vesicles show sensitive and multi-responsive properties to external stimuli. Based on these properties, we tried to
use the vesicle as a new kind of fluorescence staining material for living cells. The vesicles can effectively stain the human
breast cancer cells (MCF-7) and mice mononuclear macrophages (REW-264.7). This paper provides a better understanding
in the design and preparation of drug delivery, biomaterials and intelligent materials.
Keywords: vesicles; fluorescence; cyclodextrins; sensitive; supramolecular amphiphile
1. Introduction
Aggregates assembled by supramolecular amphiphiles
are more promising in developing responsive drug-carrier
systems with the ability to target-release (12–15).
Considerable research has been done to study the effect of
hydrophobic tail lengths, the composition of the amphi-
philic surfactant or the change of the solvent on the forma-
tion of aggregates in the general amphiphilic surfactant
solution (16–20). However, there are still few reports on
the topic of ‘supramolecular amphiphiles’. In this paper, we
describe in detail the designation, preparation and
application of a family of vesicles based on the supra-
molecular interactions of n-AQ and b-CD, or 2-O-hydro-
xypropyl-b-cyclodextrin (HP-b-CD). The vesicles were
visualised with transmission electron microscopy (TEM),
scanning electron microscopy (SEM), dynamic light
scattering (DLS), epi fluorescence microscopy (EFM) and
the mechanism was suggested based on the experimental
results of UV, fluorescence spectrum, 1H NMR and simula-
tion in the software Materials 4.3. We discuss the effects of
hydrophobic tail lengths and the change of the solvent
composition on the formation of vesicles.
Cyclodextrins (CDs) are a series of a-1,4-linked cyclic
oligosaccharides composed of 6, 7 or 8 D-(þ)-glucose
repeat units corresponding to a-, b- and g-CDs,
respectively (1). Self-assembly vesicles made from CDs
are utilised extensively for their combined properties of
liposomes and macro-cyclic host molecules (2–4), which
creates a great potential for the development of
encapsulating and solubilisation of drugs, or the
recognisation and combination of the specific types of
guest molecules (5–8).
It has been found that CDs can complex various guest
molecules (9–11), which may be applied to building novel
‘supramolecular amphiphiles’ (12, 13) (Figure 1). The
self-assembly of ‘supramolecular amphiphiles’ into
vesicles can be effective and simple, but is complicated
by modified CDs (14). It can be inferred that the inclusion
phenomenon plays the key role in combining the
hydrophobic tail and the hydrophilic head together. It is
known that the supramolecular inclusion is affected by
some stimuli (1, 5–8), which also means that the vesicles
based on the supramolecular amphiphiles are multi-
responsive and may therefore be applied in the targeted
release of some special molecules.
The vesicles showed sensitive and multi-responsive
properties to external stimuli. Based on these properties, we
managed to use the vesicle as a new kind of fluorescence
*Corresponding author. Email: haoay@sdu.edu.cn
† These authors contributed equally to this work.
ISSN 1061-0278 print/ISSN 1029-0478 online
q 2011 Taylor & Francis
DOI: 10.1080/10610278.2010.514614
http://www.informaworld.com

352
T. Sun et al.
2.2 Measurements and methods
Hydrophobic
1H and 13C NMR spectra were carried out on API Bruker
Avance 400 M NMR at room temperature (r.t.) with
CD3COCD3 as the solution and TMS as the reference. The
experiment of chemical shifts of H between 18-AQ/b-CD
and b-CD was carried out in a solution of 1025 mol/l in
D2O and CD3OD (1:1, by volume). IR spectra were
obtained on an Avatar 370 FT-IR spectrometer.
Hydrophobic tail
Hydrophilic head
Hydrophobic tail
Hydrophilic head
General amphiphiles
Supramolecular amphiphiles
Figure 1. Comparison between general amphiphiles and
supramolecular amphiphiles.
All samples for TEM were prepared by the
phosphotungstic acid staining technique using a JEM-
100CX electron microscope. SEM images were obtained
with the Hitachi S-4800 scanning electron microscope by
coating the vesicular solution to the base plate and then
dried and sputter-coated with gold.
staining material for living cells; however, there are still
more theoretical than practical applications of vesicles. It
was found that the chosen cells were stained evenly and
effectively. We believe that this study may provide a
promising new method to design artificial supramolecular
systems to be used in biomaterials. The vesicle system
could also provide new references in intelligent materials,
medicine and pharmacy, and may turn over a new leaf for
the practical application of vesicles.
DLS measurements were carried out with the Wyatt
QELS Technology DAWN HELEOS instrument poised at
r.t. by using a 12-angle replaced detector in a scintillation
vial and a 50 mW solid-state laser (l ¼ 658.0 nm). All
solutions used in DLS were filtered through a 0.45 mm
filter before detection.
UV/vis spectra were recorded at r.t. with a TU-1800pc
UV/vis spectrophotometer. The fluorescence spectrum was
taken using a Hitachi F-4500 spectrophotometer (Japan)
operated at an excitation wavelength of 488 nm and a slit
2. Experimental
2.1 Materials
width of 10 nm. QDs at a concentration of 1.0 £ 1029
M
L-Nitroanthraquinone, N-methylamino-L-AQ (L-AQ) and
L-aminoanthraquinone (n-AQ) were gifts from Shandong
Aokete Chemical Reagent Co. Ltd, China. b-CD was
purchased from Guangdong Yunan Chemical Reagent Co.
Ltd, China and recrystallised twice from distilled water
and dried by vacuum for 12 h. HP-b-CD, with an n ¼ 4.8
substituting degree, was purchased from Zibo Xinda
Chemical Reagent Co. Ltd, China. N,N-Dimethylforma-
mide (DMF) was first dried by MgSO4 for 24 h and then
distilled by vacuum. All other reagents were purchased
from Country Medicine Reagent Co. Ltd, China. All these
other organic reagents were analytically pure and used as
received. Ampicillin, piroxicam, simvastatin and amox-
icillin were supplied by Jien Medicament Research
Company, China. Thin layer chromatography (TLC)
analysis was performed on glass plates precoated with
silica gel F254, which were obtained from Qingdao
Haiyang Chemical, China. The developer used was ethyl
acetate–petroleum ether (1:5, by volume).
were measured both in PBS (pH ¼ 7.4) solution and borate
buffer solution (pH ¼ 8.3). All measurements were
performed at r.t.
EFM imaging was performed with an Olympus IX81
fluorescence microscope (Tokyo, Japan) equipped with a
high-numerical-aperture
60 £ (1.45 NA)
and
100 £ (1.40 NA) oil-immersion objective lens, a mercury
lamp source, a mirror unit consisting of a 330–385 nm
excitation filter (BP330-385), a 455 nm dichromatic mirror
(DM 455), an emission filter (IF510-550) and a 16-bit
thermoelectrically cooled EMCCD (Cascade 512B;
Tucson, AZ, USA). Imaging acquisition and data analysis
were performed using MetaMorph software (Universal
Imaging, Downingtown, PA, USA).
Fluorescence microscopy was performed with an
Olympus IX71 fluorescence microscope (Tokyo, Japan)
equipped with a high-numerical-aperture 100 £ (1.40 NA)
oil-immersion objective lens, a mercury lamp source,
ultraviolet light emission and fluorescence detection mode.
The sonication was performed on KQ116 ultrasonic
cleaners, Kunshan ultrasonic apparatus Co. Ltd, China.
MCF-7, REW-264.7 and HeLa cells were cultured in
the DMEM medium, at 36.5 6 0.58C, 5% CO2, pH ¼ 7.0–
7.4 and a permeate pressure ¼ 0.26–0.32 mol/l. Cell
suspensions, which meet counting requirements, were
filled in corresponding flasks with a proper culture
medium, placed in the incubator for 3 h, and then cultured
continuously after replacing the medium. Phosphate
buffered saline (PBS) was prepared by adding 8.5 g
NaCl, 2.85 g Na2HPO4ꢀ12H2O, 0.2 g KCl and 0.27 g
KH2PO4 into 1000 ml distilled water and then sonicated for
20 min at 300 K.
2.3 Synthesis and characterisation of n-AQ
Alkylamine directly reacted with L-nitroanthraquinone in
DMF without a catalyst, to prepare nine anthraquinone
derivates (n-AQs): N-isopropylamino-L-anthraquinone (3i-
AQ), N-n-butylamino-L-anthraquinone (4-AQ), N-cyclo-
hexylamino-L-anthraquinone (6c-AQ), N-n-hexylamino-L-
anthraquinone (6-AQ), N-n-decylamino-L-anthraquinone

Supramolecular Chemistry
353
Table 1. Synthesis of n-AQs.
Entry
R-NH2
Product
a
c
...
b
()15
R'
O
NO2
HN
O
HN
O
O
8
5
1
2
3
16-AQ
NH2(CH2)15CH3
DMF, 125°C
7
6
+
H2N R
10 h
4
O
O
O
()17
Entry
R-NH2
Product
HN
18-AQ
NH2(CH2)17CH3
O
HN
3i-AQ
H2N
O
O
(10-AQ), N-n-dodecylamino-L-anthraquinone (12-AQ),
N-n-tetradecyl-L-anthraquinone (14-AQ), N-hexadecyl-
amino-L-anthraquinone (16-AQ) and N-octadecylamino-
L-anthraquinone (18-AQ) (Table 1). This method is more
convenient than the previous method (21). DMF was
chosen for its excellent solubility.
O
HN
4-AQ
NH2(CH2)3CH3
O
L-Nitroanthraquinone (2.01 g, 8 mmol) was allowed to
react with alkylamine (16 mmol) in DMF (8 ml) at 1258C,
refluxing for 10 h. The reaction was monitored by TLC.
The reaction mixture was then cooled and poured into
water, and filtered under reduced pressure. The crude
product was washed with water, and further purified by
silica gel column chromatography with a mixture eluent of
ethyl acetate with petroleum ether (1:20, by volume).
O
HN
6c-AQ
H2N
O
O
O
HN
6-AQ
NH2(CH2)5CH3
2.4 Characterisation of n-AQ
2.4.1 Data of 3i-AQ
Red powder; mp ¼ 195–1978C; Yield, 94%; Rf ¼ 0.65;
1H NMR (TMS, d ppm): 8.32–8.30 (q, 1H, H-6AQ), 8.22–
8.20 (q, 1H, H-7AQ), 7.90–7.84 (m, 2H, H-5AQ, H-8AQ),
7.68–7.64 (q, 1H, H-3AQ), 7.54–7.52 (q, 1H, H-4AQ),
7.32–7.30 (d, 1H, H-2AQ), 4.02–4.00 (m, 1H, H-CHa),
2.71 (s, 1H, NH), 1.39–1.37 (d, 6H, H-CHb3); FT-IR (KBr
plate, n cm21): 3243.42 (m, nNZH), 1627.72 (m, dNZH),
1662.25 (vs, br, nCvO).
()9
HN
O
10-AQ
NH2(CH2)9CH3
O
O
()11
HN
HN
12-AQ
14-AQ
NH2(CH2)11CH3
2.4.2 Data of 4-AQ
1
Red powder; mp ¼ 81–828C; Yield, 93%; Rf ¼ 0.65; H
O
O
NMR (TMS, d ppm): 8.31–8.29 (q, 1H, H-6AQ), 8.22–
8.20 (q, 1H, H-7AQ), 7.92–7.82 (m, 2H, H-5AQ, H-8AQ),
7.67–7.64 (t, 1H, H-3AQ), 7.54–7.53 (d, 1H, H-4AQ),
7.29–7.27 (d, 1H, H-2AQ), 3.48–3.43 (q, 2H, H-CHa2),
2.80 (s, 1H, NH), 1.82–1.75 (m, 2H, H-CHb2), 1.61–1.52
(m, 2H, H-CHc2), 1.04–1.01 (t, 3H, H-CHd3); FT-IR (KBr
plate, n cm21): 3245.67 (m, nNZH), 1630.83 (m, dNZH),
1662.59 (vs, br, nCvO).
()13
NH2(CH2)13CH3
O

354
T. Sun et al.
2.4.3 Data of 6c-AQ
2.4.7 Data of 14-AQ
Red powder; mp ¼ 182–1838C; Yield, 95%; Rf ¼ 0.67;
1H NMR (TMS, d ppm): 8.32–8.30 (q, 1H, H-6AQ), 8.22–
8.20 (q, 1H, H-7AQ), 7.92–7.82 (m, 2H, H-5AQ, H-8AQ),
7.65–7.61 (q, 1H, H-3AQ), 7.53–7.51 (q, 1H, H-4AQ),
7.34–7.31 (d, 1H, H-2AQ), 3.76–3.72 (m, 1H, H-CHa),
2.79 (s, 1H, NH), 1.86–1.51 (d, 8H, H-CHb2–c), 0.98–0.95
(m, 2H, H-CHc2); FT-IR (KBr plate, n cm21): 3247.73 (m,
Orange powder; mp ¼ 89–908C; Yield, 90%; Rf ¼ 0.75;
1H NMR (TMS, d ppm): 8.32–8.30 (q, 1H, H-6AQ), 8.22–
8.20 (q, 1H, H-7AQ), 7.92–7.82 (m, 2H, H-5AQ, H-8AQ),
7.68–7.64 (q, 1H, H-3AQ), 7.55–7.53 (q, 1H, H-4AQ),
7.30–7.27 (d, 1H, H-2AQ), 3.47–3.44 (q, 2H, H-CHa2),
2.80 (s, 1H, NH), 1.83–1.80 (m, 2H, H-CHb2), 1.58–1.51
(m, 2H, H-CHc2), 1.46–1.29 (m, 20H, H-CHd2–m), 0.90–
0.87 (t, 3H, H-CHn3); FT-IR (KBr plate, n cm21): 3298.17
(m, nNZH), 1628.94 (m, dNZH), 1661.54 (vs, br, nCvO).
n
NZH), 1630.06 (m, dNZH), 1662.28 (vs, br, nCvO).
2.4.4 Data of 6-AQ
2.4.8 Data of 16-AQ
1
Red powder; mp ¼ 80–818C; Yield, 91%; Rf ¼ 0.65; H
NMR (TMS, d ppm): 8.28–8.26 (q, 1H, H-6AQ), 8.20–
8.18 (q, 1H, H-7AQ), 7.90–7.80 (m, 2H, H-5AQ, H-8AQ),
7.64–7.60 (q, 1H, H-3AQ), 7.51–7.49 (q, 1H, H-4AQ),
7.24–7.13 (d, 1H, H-2AQ), 2.80 (s, 1H, NH), 1.82–1.75
(m, 2H, H-CHb2), 1.55–1.50 (m, 2H, H-CHc2), 1.43–1.36
(m, 4H, H-CH2d–e), 0.95–0.92 (t, 3H, H-CHf3); 13C NMR
(400 MHz, CD3COCD3, r.t., TMS, d ppm): 184.46 (CvO),
182.91 (CvO), 151.85, 135.32, 134.94, 134.52, 134.02,
133.06, 132.96, 126.48, 126.23, 118.07, 114.87, 112.53 (C
of benzene rings), 42.56 (NHZC H2), 31.39–13.40
(11C b–f); FT-IR (KBr plate, n cm21): 3242.77 (m,
Orange powder; mp ¼ 89–908C; Yield, 82%; Rf ¼ 0.75;
1H NMR (TMS, d ppm): 8.32–8.30 (d, 1H, H-6AQ), 8.22–
8.20 (d, 1H, H-7AQ), 7.90–7.80 (m, 2H, H-5AQ, H-8AQ),
7.66–7.62 (t, 1H, H-3AQ), 7.55–7.53 (d, 1H, H-4AQ),
7.28–7.25 (d, 1H, H-2AQ), 3.48–3.43 (q, 2H, H-CHa2),
2.61 (s, 1H, NH), 1.85–1.78 (m, 2H, H-CHb2), 1.60–1.53
(m, 2H, H-CHc2), 1.47–1.31 (m, 24H, H-CHd2–o), 0.90–
0.88 (t, 3H, H-CHp3); FT-IR (KBr plate, n cm21): 3241.88
(m, nNZH), 1628.44 (m, dNZH), 1669.11 (vs, br, nCvO).
2.4.9 Data of 18-AQ
n
NZH), 1627.57 (m, dNZH), 1665.81 (vs, br, nCvO).
Orange powder; mp ¼ 85–868C; Yield, 87%; Rf ¼ 0.76;
1H NMR (TMS, d ppm): 8.23 (d, 1H, H-6AQ), 8.21–8.20
(d, 1H, H-7AQ), 7.94–7.82 (m, 2H, H-5AQ, H-8AQ), 7.70–
7.67 (t, 1H, H-3AQ), 7.56–7.53 (q, 1H, H-4AQ), 7.31–7.28
(q, 1H, H-2AQ), 3.50–3.43 (q, 2H, H-CH2a), 2.85 (s, 1H,
NH), 1.87–1.76 (m, 2H, H-CHb2), 1.56–1.51 (m, 2H,
H-CHc2), 1.45–1.29 (m, 28H, H-CHd2–q), 0.91–0.86 (t, 3H,
H-CHr3); FT-IR (KBr plate, n cm21): 3242.34 (m, nNZH),
1628.74 (m, dNZH), 1669.36 (vs, br, nCvO).
2.4.5 Data of 10-AQ
1
Red powder; mp ¼ 82–838C; Yield, 87%; Rf ¼ 0.63; H
NMR (TMS, d ppm): 8.33–8.30 (q, 1H, H-6AQ), 8.23–
8.20 (q, 1H, H-7AQ), 7.94–7.82 (m, 2H, H-5AQ, H-8AQ),
7.70–7.64 (t, 1H, H-3AQ), 7.55–7.52 (q, 1H, H-4AQ),
7.30–7.28 (d, 1H, H-2AQ), 3.50–3.43 (q, 2H, H-CHa2),
2.84 (s, 1H, NH), 1.86–1.76 (m, 2H, H-CHb2), 1.60–1.50
(m, 2H, H-CHc2), 1.46–1.30 (m, 12H, H-CHd2–i), 0.91–
0.86 (t, 3H, H-CHj3); FT-IR (KBr plate, n cm21): 3296.63
(m, nNZH), 1628.73 (m, dNZH), 1661.70 (vs, br, nCvO).
2.5 Preparation of vesicles
Two equimolar solutions, one of n-AQ and the other of CD,
were prepared with triply distilled water and methanol (1:1,
by volume). All sample solutions for the investigation were
freshly prepared by diluting the stock solution. Considering
the poor solubility of n-AQ, the proper concentration for
the vesicular formation was tested and chosen to be
1025 mol/l, for both n-AQ and CD. The sample solutions
contained the same volume of n-AQ (2 £ 1025 mol/l) and
of CD (2 £ 1025 mol/l) solutions, and then ultrasonicated
for 20 min at 300 K before detection.
2.4.6 Data of 12-AQ
Orange powder; mp ¼ 83.8–84.18C; Yield, 84%;
1
Rf ¼ 0.75; H NMR (TMS, d ppm): 8.29–8.27 (q, 1H,
H-6AQ), 8.21–8.18 (q, 1H, H-7AQ), 7.90–7.81 (m, 2H, H-
5AQ, H-8AQ), 7.65–7.61 (q, 1H, H-3AQ), 7.52–7.50 (q, 1H,
H-4AQ), 7.25–7.23 (d, 1H, H-2AQ), 3.45–3.40 (q, 2H,
H-CHa2), 2.80 (s, 1H, NH), 1.83–1.76 (m, 2H, H-CHb2),
1.56–1.50 (m, 2H, H-CHc2), 1.45–1.29 (m, 16H,
H-CHd2–k), 0.90 (t, 3H, H-CHl3 ); 13C NMR (400 MHz,
CD3COCD3, r.t., TMS, d ppm): 184.47 (CvO), 182.91
(CvO), 151.87, 135.33, 134.94, 134.53, 134.03, 133.07,
132.96, 126.48, 126.24, 118.09, 114.88, 112.54 (C of
benzene rings), 42.54 (NH-C H2), 31.74–13.44 (11C b–l);
FT-IR (KBr plate, n cm21): 3296.44 (m, nNZH), 1629.03
(m, dNZH), 1661.94 (vs, br, nCvO).
The effect of an external stimulus was investigated by
adding an external irritant to the sample solutions.
2.6 Detection of the stoichiometries of the n-AQ/b-CD
complex
Two equimolar stock solutions (1024 mol/l), one of n-AQ
(g) and the other of b-CD (h), were prepared. A set of

Supramolecular Chemistry
355
working solutions was obtained by mixing Vg ml of the n-
AQ compound stock solution with (Vt 2 Vh) ml of the
stock b-CD solution, where Vt is a fixed total volume and
Vg is a variable value (from 0 to 10 ml, 0 # Vg # Vt).
aggregates formed by the ‘supramolecular amphiphiles’.
Self-assembled aggregates such as vesicles (Figure 2),
nanospheres (Figure 3) and micelles were formed, as can
be seen from the TEM images. It can be inferred that
methanol is adverse to the formation of vesicles, as listed
in the Supporting Information, available online. This may
be attributed to the single hydrogen-binding site and to an
extent to methanol occupying the cavity of CD (1, 9–11).
It is known that due to the solvophobic theory, the
composition of solvents may affect the microstructure in
solution (22). It was thought that vesicles formed in the
solvent of pure water might have promising applications in
biomaterials. However, these vesicles were not stable,
because of the extremely low solubility of n-AQ in an
aqueous solution. Although CDs play a role in increasing
the solubility of the guest molecules, precipitation
appeared when undisturbed for 2 h, which suggests that
the pure-water system is more unstable. Therefore, the
addition of the organic solvent is necessary. From the TEM
observation, it was also found that the regularity of
the aggregates in water/methanol ¼ 1:1 (by volume) is
much better, which could pave the way for the theoretical
research of supramolecular amphiphiles, such as the
critical tail length to form vesicles. HP-b-CD is
more soluble in an aqueous solution than b-CD; however,
the existence of hydroxypropyl is also a hindrance to the
inclusion of b-CD and guest molecules (23).
2.7 Measure of the fluorescence spectrum of 18-AQ in
the presence of different concentrations of b-CD
A set of working solutions was obtained by mixing
different amounts of the b-CD stock solution with the 18-
AQ compound stock solution of 1025 mol/l. Nos 0–5
represent the b-CD concentrations of 0, 1025, 2 £ 1025
,
3 £ 1025, 4 £ 1025 and 5 £ 1025 mol/l, respectively.
2.8 Atomic-based MD simulation
In order to construct the intersimulation model, a bilayer
that contained nine pairs of 10-AQ/b-CD units was placed
3
˚
in the middle of a tetragonal box of 42 £ 42 £ 70 A ,
surrounded by a mixture consisting of water and methanol
(molar ratio ¼ 2.25:1; Figure 7). The system yields
approximately 1025 molar solutions according to the
experimental data. Application of periodic boundary con-
ditions with a unit cell produces a vesicle bilayer
perpendicular to the z-axis.
The system was first minimised 10,000 steps of
steepest descent minimisation to avoid bad contacts. Then,
the MD simulation was carried out in the NVT ensemble
with constant particle number, volume and temperature of
298 K with a time step of 1 fs. The non-bonded interactions
3.1 Morphologies and sizes of the vesicles
˚
were cut off at 12 A, and long-range electrostatic inter-
Closed vesicular structures (Figure 2) were observed clearly
by TEM with phosphotungstic acid as the staining agent,
which is a reliable and versatile method for studying the
microaggregates. The spheres with core–shell structures
were observed. These observations are similar to the
vesicular morphologies obtained by Zhang et al. (12, 13).
The particles show a significant contrast between the centre
and the periphery, which is the typical character of the
vesicular structure (24, 25). For further confirmation of
theeffectoftheinclusioncomplexes, theindividualsolutions
of n-AQs or CDs were detected by TEM separately and no
regular aggregates were found. DLS measurements were
also performed to measure the average diameters of vesicles,
and the results for the six systems are shown in Figure 4. As
an example, Figure 2(a) shows that the particles are spherical
with diameters ranging from 190 to 210 nm, which is slightly
smaller than the results found by DLS. This seems
reasonable because TEM and DLS showed solid and swollen
vesicles, respectively (24, 25). Furthermore, typical particle
aggregates formed by 14-AQ/b-CD and 18-AQ/HP-b-CD in
pure water are shown in Figure 3.
actions were accounted for using the Ewald method. The
COMPASS force field was employed in the simulation.
The molecular modelling software, Materials Studio 4.3
from Accelrys, Inc., USA (http://accelrys.com/) was used
to perform the calculations.
2.9 Stains of living cells
In a separate culture flask, 10 ml of MCF-7 cells with a
density of 105 ml21 were cultured in a wall-adhesive
mode. Twenty microlitres of the vesicle solution of 12-
AQ/b-CD (1025 mol/l) were added to the liquid medium
in a culture flask and mixed well. The cells were then
successively cultured in a cell incubator for 3 h. The basic
culture medium was then removed and washed three times
with 5 ml of PBS. In the same way, REW-264.7 cells were
cultured and then 18-AQ/b-CD (1025 mol/l) and 18-AQ
(1025 mol/l) were used to stain both cell lines.
3. Results and discussion
Multiple factors, including the tail length (ranging from
C0 to C18), the composition of the solvent (methanol:
water ¼ 1:0, 2:1, 1:1, 1:2, 0:1, by volume) and the
host molecules (b-CD or HP-b-CD), affected the
SEM (Figure 5) and EFM (Figure 6) were also under-
taken to investigate the vesicular structure. SEM imaging
provided further evidence for the formation of vesicular
structures. The technology of sputter-coating with gold on

356
T. Sun et al.
Figure 2. TEM images of (a) 6-AQ/b-CD; (b) 10-AQ/b-CD; (c) 12-AQ/b-CD; (d) 14-AQ/b-CD; (e) 16-AQ/b-CD; (f) 18-AQ/b-CD in
a solution of water/methanol ¼ 1:1 (by volume) with phosphotungstic acid as the negative staining agent; scale bars ¼ 100 nm.
the microaggregates’ surface can be applied to prepare
organic samples for SEM (26–28). However, the solid
vesicular structure may collapse to form holes for the high-
energy impacts as observed in SEM (29, 30), which also
suggested the sensitive property of the vesicles. The colour
contrast of the SEM images, hollow caves with diameters
ranging approximately from 100 to 200 nm, was close to the
results of TEM and DLS.
Anthraquinone (AQ) and its derivatives can be
applied as probes in biochemistry (31–33), analytical
Figure 3. TEM images of (a) 14-AQ/b-CD; (b) 18-AQ/HP-b-CD in pure water; scale bars ¼ 100 nm.

Supramolecular Chemistry
357
6-AQ/β-CD
10-AQ/β-CD
12-AQ/β-CD
14-AQ/β-CD
16-AQ/β-CD
18-AQ/β-CD
8
7
6
5
4
3
2
1
0
–1
–100
0
100 200 300 400 500 600 700
Rh (nm)
Figure 5. SEM images of 18-AQ/b-CD at r.t.; scale
bar ¼ 2 mm.
Figure 4. DLS of n-AQ/b-CD in
water/methanol ¼ 1:1 (by volume) at r.t.
a
solution of
6-AQ/b-CD were chosen as the examples. The exper-
imental curve (Figure 7) describes the interactions between
n-AQ and b-CD in the solution of water/methanol (1:1, by
volume). It reached its maximum at a molar fraction of 0.5,
which indicates that the complex stoichiometry of 18-
AQ/b-CD and 6-AQ/b-CD in a solution of water:methanol
(1:1, by volume) is 1:1 (40, 41).
chemistry (34) and physical chemistry (35, 36) because of
their strong fluorescence. 12-AQ/b-CD and 18-AQ/b-CD
in a solution of water/methanol ¼ 1:1 (by volume) were
taken as examples. Under the fluorescence microscope,
several drops of n-AQ/b-CD solution placed on the glass
slide revealed clear microspheres with strong fluorescence
and were found to be in typical Brownian movement
(Figure 6(a)). The study on the Brownian movement of
nanoparticles is useful in the analysis of the vesicle-gel
transformation process (37). The bilayers could not be
clearly recognised because of the limited amplification of
EFM ( £ 100) (38, 39). However, it is clear that sphere
structures were formed and dispersed homogeneously in
the solution. The property of fluorescence was success-
fully implanted into the vesicles.
It was found that the fluorescence intensity of 18-AQ
was strengthened when b-CD was added into the solution
(Figure 8). According to the literature (42), these small but
significant changes in the absorption intensity upon
addition of b-CD to 18-AQ suggested the formation of
an 18-AQ/b-CD complex in the solution of water/
methanol (1:1, by volume). The fluorescence enhancement
was attributed to the b-CD cavity, which can supply a
microenvironment and to a large extent protect the guest
AQ from contacting the surrounding water molecules. This
led to an increase in the fluorescence quantum yield and
intensity, which suggested that 18-AQ entered the cavity of
b-CD to form supramolecular inclusion (43).
3.2 The possible formation mechanism of the vesicles
The complex stoichiometry was confirmed by UV
spectroscopy using Job’s plot method. 18-AQ/b-CD and
Figure 6. EFM images of n-AQ/b-CD in a solution of water/methanol ¼ 1:1 (by volume) at r.t. excited at 340 nm with mercury lamp:
(a) £ 60, 18-AQ/b-CD; (b) £ 60, 6-AQ/b-CD; scale bars ¼ 5 mm.

358
T. Sun et al.
(a)
(b)
0.6
0.4
0.2
0.0
0.015
0.010
0.005
0.000
0.0
0.2
0.4
0.6
0.8
1.0
0.0
0.2
0.4
0.6
0.8
1.0
[18-AQ]/([18-AQ]+[β-CD])
[6-AQ]/([6-AQ]+[β-CD])
Figure 7. Job’s curve of the inclusion complex of (a) 18-AQ/b-CD, the DA in the wavelength of 266 nm was picked to obtain Job’s
curve; (b) 6-AQ/b-CD in the solvent (V(methanol):V(water) ¼ 1:1) by UV, the DA in the wavelength of 516 nm was picked to obtain Job’s
curve.
The most direct and dependable evidence for the
1
supramolecular inclusion of 18-AQ and b-CD is from H
such as strict fit, van der Waals’ interactions, hydrogen
bond and so on. A possible inclusion of n-AQ into b-CD,
˚
with a cavity opening size of 6.5 A, would be an axial
NMR, which is one of the most powerful tools for realising
supramolecular assemblies in solution. The concentration
of 18-AQ/b-CD was so low that the peak of 18-AQ was
almost undistinguishable from the baseline. However,
clear shifts of b-CD were observed, which demonstrated
the inclusion phenomenon (44–46).
inclusion, due to a suitable size of the guest molecules in
this direction (47–49). However, the inclusion of n-AQ/b-
CD is supposed to be only partial (50–52). In this case, the
unsubstituted benzene ring was inside the host’s cavity
while the central ring bearing two CvO groups as well as
the alkyl-substituted aminobenzene ring remained outside
the cavity, and participated in H-bonding with the
secondary hydroxyl groups of b-CD (51, 52) (Scheme
1). The proposed structures for inclusion complexes of b-
CD with n-AQ are given in Scheme 1. Based on the
discussion above, the anthraquinone group of N-alkyla-
mino-L-anthraquinone would partly enter the cavity of b-
CD to construct the hydrophilic ‘head’, and the alkyl chain
outside the cavity would perform the role of the
hydrophobic ‘tail’ to form a peculiar type of ‘amphiphilic
surfactant’. Furthermore, the inclusion phenomenon was
investigated by UV and fluorescence spectra. Based on the
experimental results, a possible mechanism was proposed,
as illustrated in Scheme 1. While being ultrasonicated and
well dispersed in the solution, the supramolecular complex
could self-assemble into vesicles. The above analysis
indicates that the inclusion phenomenon was the main
control of the vesicle formation.
In the presence of 18-AQ, almost all the hydrogen
resonances of b-CD showed chemical shifts (Table 2). 18-
AQ is a relatively large molecule compared with other
regular guest molecules, such as benzene, ferrocene and
adamantane, so 18-AQ may exert a broad effect to
hydrogen atoms H1–H6 of b-CD.
CDs, which are cyclic oligosaccharides with hydro-
phobic cavities, have the capability to bind substrates
selectively to form inclusion complexes (1–5). The
primary criterion for the inclusion of a guest molecule
within the host’s cavity is its size and then other factors
2000
5
1600
0
1200
3.3 Demonstration of the vesicle model
800
400
An MD simulation was performed to validate the possibility
of the above mechanism model. Atomic-based MD
simulations can play a powerful role in indicating the
properties at a microscopic level and are considered as
complements to experiments. In this paper, a classical MD
simulation of the 10-AQ/b-CD vesicle structure was
performed to investigate the possibility of the above-
mentioned mechanism model. Since it could be very time-
consuming to obtain a spontaneous bilayer structure from a
random initial configuration, we started the simulations from
the pre-assembled state, as has been reported in most other
0
684 688 692 696 700 704 708 712
Wavelength (nm)
Figure 8. Fluorescence intensity spectra of 18-AQ and b-CD in
the solution of water/methanol (1:1, by volume), Nos 0–5
represent the solution with b-CD concentrations of 0, 1025
,
2 £ 1025, 3 £ 1025, 4 £ 1025, 5 £ 1025 and 6 £ 1025 mol/l,
respectively. The excitation wavelength is 380 nm.

Supramolecular Chemistry
Table 2. The chemical shifts of H NMR from H-1 to H-6.
359
1
Entry
H-1
H-2
H-3
H-4
H-5
H-6
d (b-CD)a
d (18-AQ/b-CD)b
Dd
4.977
–
–
3.696
3.746
0.050
3.585
3.593
0.008
3.499
3.511
0.012
3.859
3.913
0.054
3.800
3.853
0.053
a All the samples were measured in a solution of D2O and CD3OD (1:1, by volume), T ¼ 300 K.
b The complex of 18-AQ/b-CD was measured with a concentration of 1025 mol/l in order to coincide with the concentration of the vesicle formation.
simulation systems (53–59). Although the bilayer takes a
relatively long time to form, once formed, it is stable as
shown in Figure 9. Employing the space-extension principle,
the part of the bilayer shown in Figure 9 can begeneralised to
the whole vesicle. The obtained results were similar to the
suggested mechanism shown in Scheme 1, which further
confirmed our presumption. This was the first time that MD
simulation experiments wereused to study the mechanism of
vesicles self-assembled by ‘supramolecular amphiphiles’.
This is also the first time to study the effect of the ‘tail’
length to the formation of vesicles based on ‘supramole-
cular amphiphiles’. 6-AQ, 10-AQ, 12-AQ, 14-AQ, 16-AQ
and 18-AQ were able to self-assemble into vesicles with b-
CDs, while 6c-AQ, 4-AQ, 3i-AQ, N-methylamino-L-AQ, L-
aminoanthraquinone and AQ were not able to self-
assemble. The inability to self assemble is likely because
the hydrophobic tail chains are too short and decrease the
‘hydrophobic–hydrophobic interaction’ between the
building blocks. From the above results, the hydrophobic
‘tail’ of the alkyl chain with six carbon atoms was
considered as the lower limit to self-assemble into vesicular
structures in this supramolecular system. Moreover, the
fact that 6-AQ and 6c-AQ show different results in this
system should be emphasised: the length but not the
volume of the hydrophobic ‘tail’ seems to play a more
important role in the formation of vesicles’ bilayers.
3.4 The properties of the vesicles
3.4.1 Sensitive and multi-responsive properties of the
vesicles
The vesicles disappeared upon the addition of equimolar
CuCl2. The shift of the UV peaks of n-AQ in the presence
of Cu2þ indicates that n-AQ can complex with this ion
(Figure 10). From the literature (60, 61), it is known that
Cu2þ easily binds to the N atom. The vesicles also
6.0Å
OH
Å
O
O
7 . 9
OH
OH
7
6.5Å
N
H
a
c
H
O
O
O
()
H
O HN
n
8
b
Å
1
O
2
7
6
3
5 . 4 0 3
4
5
O
9.307Å
n = 1, 5, 7, 9, 11, 13
Self-assembly
Scheme 1. The possible mechanism of the vesicle formation based on the experimental results.

360
T. Sun et al.
responsive materials, especially for the drug release
at cancer cells, which can cause an acidic environment
(63–66).
Ampicillin, piroxicam, simvastatin and amoxicillin
(Scheme 2, the concentrations were all chosen as
1025 mol/l) were separately added into the vesicle solution
of 18-AQ/b-CD to investigate its response to the drug
molecules. As indicated in TEM, vesicles were destroyed
with the addition of the three drugs, which may be due to
the inclusion competition between n-AQ and the drug
molecule (Scheme 3), since it was reported that these
drugs could form 1:1 inclusion with b-CD (67). Those
non-covalent interactions of receptors and ligands, or the
host and the guest at the vesicle surfaces resemble the
recognition processes at biological membranes. This
property may further our understanding in biological
membranes through the biomimetic supramolecular
chemistry of vesicles (68–71).
Figure 9. Results of the MD simulation of 10-AQ/b-CD in the
solution of methanol/water ¼ 1:1 by volume.
responded to Hþ. The UV spectrum, similar to the results
of the addition of CuCl2, also had a significant variation
with the addition of acetic acid, which indicates the change
from secondary amine to quaternary ammonium.
3.5 Application of the vesicle system in cell staining
Vesicles, enclosing a volume with membranes consisting
of a bilayer or a multilayer of specific molecules, have
drawn increasing attention for the hope of applications in
drug and gene delivery (72–77), nanoreactors (78, 79) and
artificial cell membranes (69–71). However, vesicles, to a
certain extent, seem to have more potential than practical
application.
Meanwhile, the UV adsorption related to 18-AQ/Cu2þ
and 18-AQ/Hþ changed in the presence of b-CD, which
suggests that b-CD can still include 18-AQ upon addition
of Cu2þ or Hþ (62). However, both Cu2þ and Hþ are
harmful to the formation of vesicles from the TEM
observations. This may be attributed to the increase in the
electrostatic repulsive force between the ‘building blocks’,
which makes it difficult for the aggregates to form
(Scheme 3). The results described may provide new
opportunities in mimicking some biological processes or
building new pH-controlled drug-release system and pH-
From the above experimental results, it is clear that the
vesicles are multi-responsive, or in other words, the
vesicles are sensitive. Hence, we can deduce that when
introduced into the cell suspension with a complicated
composition, vesicles may collapse, and the guest
(a)
(b)
18-AQ
18-AQ/β-CD
18-AQ
18-AQ/H+
18-AQ/β-CD
18-AQ/β-CD/H+
18-AQ/Cu2+
1.6
2.0
1.6
1.2
0.8
0.4
0.0
18-AQ/β-CD/Cu2+
1.2
0.8
0.4
200
220
240
260
280
300
200
250
300
350
Wavelengh/nm
Wavelength/nm
Figure 10. (a) UV spectra of 18-AQ (black line), 18-AQ/b-CD (red line), the mixture of 18-AQ and CuCl2 (blue line, solution of
[CuCl2] ¼ 1025 mol/l was as the baseline), the mixture of 18-AQ/b-CD and CuCl2 (green line, the solution of [CuCl2] ¼ 1025 mol/l was
as the baseline). [18-AQ] ¼ [18-AQ/b-CD] ¼ [CuCl2] ¼ 1025 mol/l. T ¼ 300 K; (b) UV spectra of 18-AQ (black line), the mixture of
18-AQ and acetic acid (red line), 18-AQ/b-CD (blue line), the mixture of 18-AQ/b-CD and acetic acid (green line). [18-AQ] ¼ [18-AQ/b-
CD] ¼ [acetic acid] ¼ 1025 mol/l. T ¼ 300 K.

Supramolecular Chemistry
361
HO
O
O
O
H
H
N
NH
O
OH
H3C
H
2 H
N
S
CH3
O
OH
S
O
HO
H3C
H
O
O
CH3
ONa
O
H
H
N
H
CH3
CH3
CH3
N
N
CH3
O
H
H
N
N
O
S
R
H
H2N
H
O
O
H3C
Amoxicillin
Piroxicam
Simvastatin
Ampicillin
Scheme 2. The chemical structures of the selected external guests.
molecules may be released to stain the cells. Images of cells
with blue fluorescence were taken using UV ray-excitation
mode. The cells were distinct when viewed with the
fluorescence microscope (Figure 11(b) and (d)). Images of
cells by fluorescence microscopy were in good accordance
with the images under natural lighting. Since cells which
are not fluorescently stained cannot be observed by
microscope under fluorescence conditions, we could
judge that n-AQ was adsorbed in the cell membrane
through the collapse of vesicles. Control experiments
showed that 18-AQ (1025 mol/l) in methanol/water (1:1,
solution by volume) could only stain the cells with very
weak but corresponding fluorescence, which can further
demonstrate the important role played by the vesicles.
Another control experiment showed that by staining the
cells with Rhodamine B (also 1025 mol/l in methanol/water
(1:1, solution by volume)) also offers a weaker and more
vague fluorescence (Figure 12).
The images showed that the cells could be stained
evenly and with strong luminous intensity. The samples
were observed by fluorescence microscopy for more than
3 h and the fluorescent intensity did not decrease, which
offers a longer fluorescence lifetime and better homogen-
eity compared with other cell stainers, such as Rhodamine
B (Figure 12). Although methanol is adverse to most cells,
a trace addition (20 ml into 10 ml) can be overlooked.
+H
+H
+H
H+ No vesicles
Cu2+
Cu2+
Cu2+
No vesicles
Vesicle
Cu2+
No vesicles
Scheme 3. Multi-responsive vesicles.

362
T. Sun et al.
Figure 11. Microscopy images of living cells after treating with the vesicular solution: REW264.7 cells stained with vesicles of 18-
AQ/b-CD: (a) under natural lighting; (b) in fluorescence microscopy; RM-1 cells stained with vesicles of 12-AQ/b-CD (c) under natural
light; (d) in fluorescence microscopy; REW264.7 cells stained with 18-AQ (1025 mol/l in methanol/water ¼ 1:1 solution by volume):
(e) under natural lighting and (f) in fluorescence microscopy.
Our methods may provide a new approach to detect
cellular localisation. This may also lead to a new way to
achieve targeted release of some anti-cancer drugs via the
replacement of guest molecules, especially when CDs,
which have molecule recognition property, are the guest
molecules. Furthermore, we did not observe any sign of
morphological damage to the cells after the treatment,
demonstrating the low toxicity of the system of n-AQ/b-
CD (80).
between CDs and glycoprotein or other molecules in the
cell membrane also plays an important role in the progress
of AQ adsorption. The instability and sensitivity of
supramolecular vesicles formed by ‘amphiphilic surfac-
tant’ were successfully applied here. In summary, through a
‘recognition–release–fusion’ process, the dyes with
fluorescence capacity can be attached to the cell
membrane. The study on the effect of fluorescent vesicles
on the inner cell organelles is still in progress.
The collapse of vesicles may be due to the change of the
environment, especially the change of the solution from
methanol/water to an aqueous solution. For then, vesicles
collapse and n-AQ is released from the CD cavity and
adsorbed by the cell membrane, since n-AQ’s solubility is
very low in an aqueous solution. The non-covalent bond
4. Conclusion
In summary, we report the designation, preparation and
application of a novel fluorescent vesicle system. The
strategy was demonstrated as follows: in order to achieve

Supramolecular Chemistry
363
(5) Wang, J.; Jiang, M. J. Am. Chem. Soc. 2006, 128,
3703–3708.
(6) Bugler, J.; Sommerdijk, N.A.J.M.; Visser, A.J.W.G.; Hoek,
A.; Nolte, R.J.M.; Engbersen, J.F.J.; Reinhoudt, D.N. J. Am.
Chem. Soc. 1999, 121, 28–33.
(7) Ravoo, B.J.; Darcy, R. Angew. Chem., Int. Ed. 2000, 39,
4324–4326.
(8) Sallas, F.; Darcy, R. Eur. J. Org. Chem. 2008, 6, 957–969.
(9) Connors, K.A. Chem. Rev. 1997, 97, 1325–1357.
(10) Rekharsky, M.V.; Inoue, Y. Chem. Rev. 1998, 98,
1875–1917.
(11) Douhal, A. Chem. Rev. 2004, 104, 1955–1976.
(12) Zhang, H.; Shen, J.; Liu, Z.; Bai, Y.; An, W.; Hao, A.
Carbohydr. Res. 2009, 344, 2028–2035.
(13) Zhang, H.; An, W.; Liu, Z.; Hao, A.; Hao, J.; Shen, J.; Zhao,
X.; Sun, H.; Sun, L. Carbohydr. Res. 2009, 345, 87–96.
(14) Jing, B.; Chen, X.; Wang, X.; Yang, C.; Xie, Y.; Qiu, H.
Chem. Eur. J. 2007, 13, 9137–9142.
(15) Guo, M.; Jiang, M.; Zhang, G. Langmuir 2008, 24,
10583–10586.
Figure 12. Fluorescence microscopy images of human aortic
smooth muscle cells after treating with Rhodamine B.
(16) Abdel-Rahem, R.; Hoffmann, H. J. Colloid Interface Sci.
2007, 312, 146–155.
(17) Joshi, J.V.; Aswal, V.K.; Goyal, P.S. Phys. B 2007, 391,
65–71.
(18) Yuet, P.K.; Blankschtein, D. Langmuir 1996, 12,
3819–3827.
(19) Zhai, L.; Zhao, M.; Sun, D.; Hao, J.; Zhang, L. J. Phys.
Chem. B 2005, 109, 5627–5630.
(20) Israelachvili, J.N. Intermolecular and Surface Forces;
Academic Press: New York, 1994.
(21) Reubke, K. US patent 1976, 4076736.
(22) Ray, A. Nature 1971, 231, 313–315.
(23) Sun, T.; Hao, A.; Shen, J.; Song, L. Synth. Commun. 2009,
39, 4309–4314.
(24) Wang, L.; Liu, H.; Hao, J. Chem. Commun. 2009,
1353–1355.
the goal, nine n-AQs with different lengths of alkyl were
synthesised by the direct reaction of L-nitroanthraquinone
and alkylamines to act as the guest molecules. With the
inclusion of n-AQ and b-CD, the supramolecular complex
can self-assemble into vesicular structures in the
methanol/water solvent, which were visualised by TEM,
SEM, DLS and EFM. The property of fluorescence was
successfully implanted into vesicles, which was observed
by EFM. The possible mechanism of the vesicle formation
was suggested based on the results of UV, fluorescence
spectrum and MD simulation. The vesicles were sensitive
and multi-responsive to external stimuli. Furthermore, the
vesicles were successfully applied in the staining of living
cells and the possible staining approach was also
suggested. We believe that the supramolecular vesicles
will serve useful in the fields of biomaterials, cell-mimic,
design of intelligent materials and molecule machines.
(25) He, Y.; Fu, P.; Shen, X.; Gao, H. Micron 2008, 39,
495–516.
(26) Mazzaglia, A.; Angelini, N.; Lombardo, D.; Micali, N.;
Patane, S.; Villari, V.; Scolaro, L.M. J. Phys. Chem. B 2005,
109, 7258–7265.
(27) Qian, J.; Wu, F. Macromolecules 2008, 41, 8921–8926.
(28) Yang, J.; Keller, M.W.; Moore, J.S.; White, S.R.; Sottos,
N.R. Macromolecules 2008, 41, 9650–9655.
(29) Kamilya, T.; Pal, P.; Mahato, M.; Talapatra, G.B. Mat. Sci.
Eng. C-Bio. Sci. 2009, 29, 1480–1485.
(30) Yuan, P.; Yang, S.; Wang, H.; Yu, M.; Zhou, X.; Lu, G.;
Zou, J.; Yu, C. Langmuir 2008, 24, 5038–5043.
(31) Kumamoto, S.; Watanabe, M.; Kawakami, N.; Nakamura,
M.; Yamana, K. Bioconj. Chem. 2008, 19, 65–69.
(32) Qiao, C.; Bi, S.; Sun, Y.; Song, D.; Zhang, H.; Zhou, W.
Spectrochim. Acta A 2008, 70, 136–143.
Acknowledgements
This work was supported by the NSFC (Grant No. 20625307),
National Basic Research Program of China (973 Program,
2009CB930103) and Graduate Independent Innovation Foun-
dation of Shandong University (GIIFSDU). We thank Ms Carla
R. Christ from Santa Barbara, USA and Dr Z. Yang from
´
Universite Pierre et Marie Curie: Paris 6 for editing the
manuscript for English corrections.
(33) Liu, Y.; Hu, N. Biosens. Bioelectron. 2007, 23, 661–667.
(34) Yamaguchi, A.; Nakano, M.; Nochi, K.; Yamashita, T.;
Morita, K.; Teramae, N. Anal. Bioanal. Chem. 2006, 386,
627–632.
(35) Zhu, L.; Khairutdinov, R.F.; Cape, J.L.; Hurst, J.K. J. Am.
Chem. Soc. 2006, 128, 825–835.
References
(1) Szejtli, J. Chem. Rev. 1998, 98, 1743–1753.
(2) Sortino, S.; Mazzaglia, A.; Scolaro, L.M.; Merlo, F.M.;
Valveri, V.; Sciortino, M.T. Biomaterials 2006, 27,
4256–4265.
(36) Bhattacharya, S.; Subramanian, M. J. Chem. Soc., Perkin
Trans. 1996, 2, 2027–2034.
(37) Jesorka, A.; Markstrom, M.; Karlsson, M.; Orwar, O.
J. Phys. Chem. B 2005, 109 (31), 14759–14763.
(38) Xu, Y.; Wang, G.; Zhao, X.; Jiang, X.; Li, Z. Langmuir
2009, 25, 2684–2688.
(3) Falvey, P.; Lim, C.W.; Darcy, R.; Revermann, T.; Karst, U.;
Giesbers, M.; Marcelis, A.T.M.; Lazar, A.; Coleman, A.;
Reinhoudt, D.; Ravoo, B.J. Chem. Eur. J. 2005, 11,
1171–1180.
(4) Mazzaglia, A.; Ravoo, B.J.; Gambadauro, R.D.P.; Mal-
lamace, F. Langmuir 2002, 18, 1945–1948.

364
T. Sun et al.
(39) Horbaschek, K.; Hoffmann, H.; Thunig, C. J. Colloid
Interface Sci. 1998, 206, 439–456.
(60) Masakatsu, S.; Motomu, K. Chem. Rev. 2008, 108,
2853–2873.
(40) MacCarthy, P. Anal. Chem. 1978, 50, 2165.
(41) Guo, M.; Jiang, M.; Zhan, G. Langmuir 2008, 24,
10583–10586.
(42) Wu, Q.; Zhu, M.; Wei, S.; Song, K.; Liu, L.; Guo, Q. J. Incl.
Phenom. Macro. 2005, 52, 93–100.
(43) Wang, Y.; Zhu, M.; Ding, X.; Ye, J.; Liu, L.; Guo, Q.
J. Phys. Chem. B 2003, 107, 14087–14093.
(44) Schneider, H.J.; Hacket, F.; Rudiger, V. Chem. Rev. 1998,
98, 1755–1785.
(45) Demarco, P.V.; Thakkar, A.L. Chem. Commun. 1970, 2–4.
(46) Redenti, E.; Szente, L.; Szejtli, J. J. Pharm. Sci. 2001, 90,
979–986.
(47) Jiang, H.; Sun, H.; Zhang, S.; Hua, R.; Xu, Y.; Jin, S.; Gong,
H.; Li, L. J. Incl. Phenom. Macro. 2007, 58, 133–138.
(48) D’Anna, F.; Riela, S.; Gruttadauria, M.; Meo, P.L.; Noto, R.
Tetrahedron 2005, 61, 4577–4583.
(49) D’Anna, F.; Riela, S.; Meo, P.L.; Noto, R. Tetrahedron
2004, 60, 5309–5314.
(61) Bernardo, K.; Leppard, S.; Robert, A.; Commenges, G.;
Dahan, F.; Meunier, B. Inorg. Chem. 1996, 35, 387–396.
(62) Dermody, D.L.; Peez, R.F.; Bergbreiter, D.E.; Crooks, R.M.
Langmuir 1999, 15, 885–890.
(63) Bhujwalla, Z.M.; McCoy, C.L.; Glickson, J.D.; Gillies,
R.J.; Stubbs, M. Br. J. Cancer 1998, 78, 606–611.
(64) Beselli, R.; Renzi, G.; Morello, R.; Altieri, F. J. Craniofac.
Surg. 2007, 18, 1051–1054.
(65) Yamagata, M.; Tannock, I.F. Br. J. Cancer 1996, 73,
1328–1334.
(66) Tannock, I.F.; Rotin, D. Cancer 1989, 49, 4373–4389.
(67) Aki, H.; Ikeda, H.; Yukawa, M. J. Ther. Anal. Calorim.
2009, 95, 421–426.
(68) Voskuhl, J.; Ravoo, B. Chem. Soc. Rev. 2009, 38, 495–505.
(69) Lehn, J.M. Science 2002, 295, 2400–2403.
(70) Shimizu, T.; Masuda, M.; Minamikawa, H. Chem. Rev.
2005, 105, 1401–1444.
(50) Shamsipur, M.; Yari, A.; Sharghi, H. Spectrochim. Acta A
2005, 62, 372–376.
(51) Petrova, S.S.; Kruppa, A.I.; Leshina, T.V. Chem. Phys. Lett.
2005, 407, 260–265.
(52) Dang, X.; Nie, M.; Tong, J.; Li, H. J. Electroanal. Chem.
1998, 448, 61–67.
(53) Wang, Z.; Larson, R.G. J. Phys. Chem. B 2009, 113,
13697–13710.
(54) Maillet, J.B.; Lachet, V.; Coveney, P.V. Phys. Chem.,
Chem. Phys. 1999, 1, 5277–5290.
(55) Yakovlev, D.S.; Boek, E.S. Langmuir 2007, 23,
6588–6597.
(56) Piotrovskaya, E.M.; Vanin, A.A.; Smirnova, N.A. Mol.
Phys. 2006, 104, 3645–3651.
(57) Boek, E.S.; den Otter, W.K.; Briels, W.J.; Iakovlev, D.
Philos. T.R. Soc. A 2004, 362, 1625–1638.
(58) Padding, J.T.; Boek, E.S.; Briels, W.J. J. Phys.: Condens.
Matter 2005, 17, 3347–3353.
(71) Discher, D.E.; Eisenberg, A. Science 2002, 297, 967–973.
(72) Allen, T.M.; Cullis, P.R. Science 2004, 303, 1818–1822.
(73) Korobko, A.V.; Backendorf, C.; van der Maarel, J.R.C.
J. Phys. Chem. B 2006, 110, 14550–14556.
(74) Guo, X.; Szoka, F. Acc. Chem. Res. 2003, 36, 335–341.
(75) Hogset, A.; Prasmickaite, L.; Selbo, P.K.; Hellum, M.;
Engesaeter, B.O.; Bonsted, A.; Berg, K. Adv. Drug Deliv.
Rev. 2004, 56, 95–115.
(76) Zou, P.; Pan, C.Y. Macromol. Rapid Commun. 2008, 29,
763–771.
(77) Jan, J.S.; Lee, S.J.; Carr, C.S.; Shantz, D.F. Chem. Mater.
2005, 17, 4310–4317.
(78) Christensen, S.M.; Stamou, D. Soft Matter 2007, 3,
828–836.
(79) Sauer, M.; Haefele, T.; Graff, A.; Nardin, C.; Meier, W.
Chem. Commun. 2001, 2452–2453.
(80) Zhou, C.; Shen, H.; Guo, Y.; Xu, L.; Niu, J.; Zhang, Z.; Du,
Z.; Chen, J.; Song, L. J. Colloid Interface Sci. 2010, 344,
279–285.
(59) Briels, W.J.; Mulder, P.; den Otter, W.K. J. Phys.: Condens.
Matter 2004, 16, 3965–3974.