A near-infrared emission fluorescent probe with multi-rotatable moieties for highly sensitive detection of mitochondrial viscosity in an inflammatory cell model

Article abstract of DOI:10.1039/C8TB02083C

A near-infrared emission fluorescent viscosity probe (TPE-V) which contains multi-rotatable moieties has been developed for the first time. TPE-V exhibited a large Stokes shift (190 nm) and a large enhancement in fluorescence intensity (100-fold) in respo

Full text of DOI:10.1039/C8TB02083C

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Guoping Chen et al.
Regulating the stemness of mesenchymal stem cells by tuning
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A near-infrared emission fluorescent probe with multi-rotatable
moieties for high sensitivity detection of mitochondrial viscosity
in inflammatory cell model
Received 00th January 20xx,
Accepted 00th January 20xx
a
a
b
a
a
DOI: 10.1039/x0xx00000x
Yanyan Ma , Yuping Zhao , Rui Guo , Linlin Zhu and Weiying Lin*
www.rsc.org/
A near-infrared emission viscosity fluorescent probe (TPE-V) which this problem, extensive molecular rotors were developed as
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contains multi-rotatable moieties was developed for the first microviscosity sensors, but most of them have short
time. TPE-V exhibited a large stokes shift (190 nm) and large emission wavelength, which may lead to damage to living
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8
enhancement of fluorescence intensity (100-fold) in response to biological systems. Furthermore, the molecular rotors are
viscosity. Moreover, TPE-V was successfully applied for detection responsive to viscosity variation. However, there is still room
of mitochondrial viscosity in inflammatory cells model.
for development more sensitive viscosity fluorescent probe.
Recently, Tang group developed a series of dyes displaying
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Viscosity is a crucial paremeter of reaction in solution, which is
mainly determined by the diffusion rate of substance. In living
system, viscosity strongly influences intracellular signal
transport, the diffusion of active metabolites and interactions
aggregation-induced emission (AIE) characters.
Mechanistic studies show that AIE phenomenon is mainly due
to restriction of intramolecular motions. According to this
characteristic, fluorescence viscosity probe based on AIE
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,2
2
2
between biomacromolecules. The changes of intracellular
viscosity are closely related to the physiological function and a
variety of diseases, such as diabetes, Alzheimer disease (AD),
fluorophore was reported.
Compared with traditional
molecular rotors, viscosity-sensitive AIE dyes contain more
rotatable parts and is more sensitive to viscosity changes in
microenvironment. However, it is still urgent to develop a
method for improving the sensitivity of detection viscosity
changes with near-infrared emission. Taking advantage of
these viscosity-dependent characteristics, we envisaged that
connection of the traditional molecular rotors with AIE dyes
can result in probes ultrasensitive to environmental viscosity
with near-infrared emission, which, however, has not yet been
reported.
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hypertension and Parkinson disease (PD). It is reported that
the viscosity is about 1-2 cP in the cellular cytoplasm of normal
cells, while in the diseased cells it is significantly increased,
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which can reach 140 cP, or even higher.
Mitochondria are
the main compartment of energy production which play
significant roles for various vital cellular processes including
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ATP production and central metabolism. Changes of
mitochondrial viscosity may influences mitochondrial network
organization and metabolite diffusion rate. Studies have
shown that the changes of mitochondrial viscosity could cause
Herein, we report a unique near-infrared (NIR) emission
mitochondrial viscosity fluorescent probe (TPE-V) which
contains multi-rotatable moieties for the first time.
Interestingly, TPE-V exhibited ultrasensitive response to
viscosity (<15 cP) and the fluorescence intensity at 650 nm
increased about 100-fold in 99 vol% glycerol. Moreover, TPE-V
showed a large Stokes’ shift (190 nm) which can avoid self-
absorption effect. Importantly, TPE-V was successfully
targeted in mitochondria and employed for monitoring
viscosity variations under characteristic pathological
conditions.
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the body to be in a state of disease. Therefore, it is significant
to develop an effective method for monitoring the viscosity
variations in the mitochondrial.
Although some analytical methods have been used to
detect viscosity including viscometer and electrochemical
analysis, nondestructive strategies appropriated for biological
samples measurements in living cells are still unmet. To solve
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lifetime increased with the increment of viscosity (1.4 -15 cP)
and exhibited a good linear relationship between log τ and log
2
η (R = 0.99148, x =0.21618) according to the Förster–
Hoffmann equation (Fig. 1d). The observed changes of
fluorescence lifetime is accordant with the restricted rotation
of TPE and indole salt groups in the system of high viscosity.
The non-radiative decay rate decreases with increasing
viscosity, and thus the fluorescence lifetime of TPE-V is
prolonged with the increase of viscosity. All these results
indicate that TPE-V can serve as an excellent fluorescent probe
for monitoring the viscosity changes.
Scheme 1. Design of near-infrared emission fluorescence viscosity probe TPE-V.
TPE contains more rotatable parts and may more
sensitive to viscosity changes. The molecular rotors can be
freely rotated in low viscosity solutions, while the rotation is
suppressed in high viscosity solutions. As shown in Fig. S1,
both TPE moiety and an indole salt moiety can response to
viscosity. According to these features, we designed a viscosity
fluorescence probe TPE-V (Scheme 1), which contained a TPE
moiety and an indole salt moiety. We anticipated that the
probe has no fluorescence under low viscosity solutions due to
the free rotation of TPE moiety and an indole salt moiety,
while in high viscosity solutions, the rotation is suppressed and
the fluorescence intensity would be dramatically enhanced. In
addition, the probe can localize in mitochondria due to the
indole cation. The synthesis steps and characterization data
were shown in supporting information.
To verify whether TPE-V is responsive to viscosity as Fig. 1. (a) The fluorescence spectra of 10 μM TPE-V in variation ratios of water-
glycerol system. λex = 460 nm. (b) The linear relationship between log I650 and log
2
designed, we first investigate the optical property of TEP-V in η, R = 0.99496, x =0.67428. (c) Fluorescence lifetime spectra of TPE-V (10 μM) in
different water−glycerol system, λex = 460 nm, λem = 650 nm. The viscosities were
2
water and viscosity solutions. As shown in Fig. S2a, TPE-V 1.4 cP-15 cP, respectively. (d) The linear relationship between log τ and log η, R =
0.99148, x =0.21618.
exhibited the maximum absorption at 440 nm in water
solution, while in 99 % V/V glycerol solution, the maximum
absorption shifted to 465 nm, which may be due to the
inhibition of rotation in viscosity solution and enlarged the
degree of conjugation. As expected, TPE-V displayed almost no
fluorescence under excited at 460 nm in water solution.
However, in 99 % V/V glycerol solution, the fluorescence
intensity enhanced about 100-fold at 650 nm (Fig. S2b), which
far higher than the reported viscosity fluorescence probes
Generally polarity is an important influence factor for
25
molecular rotors to detect viscosity,
therefore, the
fluorescence intensity of TPE-V in some solvents with different
polarity were conducted. As shown in Fig. S4, the probe TPE-V
did not show significant fluorescence changes at 650 nm in
different polar solutions compared with that in 99 % V/V
glycerol. In addition, the quantum yields of TPE-V in other low-
viscosity solvents are very low (almost about 0.025). However,
in 99 % V/V glycerol, the quantum yield is about 0.286 (Table
S2). These results demonstrate that environmental polarity
brings ignorable interferences to the viscosity detection.
(Table S1). Moreover, the fluorescence intensity of TPE-V at
650 nm was enhanced with the increase of viscosity from 1.4
cP to 950 cP (Fig. 1a) and the obvious fluorescence changes
could be observed by the naked eye (inset of Fig. 1a). As
shown in Fig. 1b, there is a good linear relationship between
To examine the specificity of TPE-V, the fluorescence
spectra of TPE-V were conducted coexisting with some
2
log I650 and log η (R =0.99) by fitting the Förster–Hoffmann
2-
possible competitive species including 500 μM S , HSO
-
3
, GSH,
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3
equation and the value of x (as high as 0.67) presented the
possibility for the monitoring the changes of viscosity in vitro.
Notably, the emission intensity of TPE-V was increased about
Cys, Hcy, (tert-butyl hydroperoxide (TBHP), ditert-butyl
2+
peroxide (DTBP), Mg , Ca , Na , Zn , K , Fe and 100 μM
2+
+
2+
+
2+
-
2 2
H O , ClO and BSA. As shown in Fig. 2, the fluorescence
10-fold in viscosity solutions from 1.4 cP to 15 cP (Fig. S3).
intensity of TPE-V had no obvious changes after treated with
other bioactive molecules. Only viscosity solution can triggered
an obviously fluorescence enhancement at 650 nm. Moreover,
the probe exhibited aggregation caused quenching (ACQ)
effect in physiological environment (Fig. S5), which avoided
the interference from the aggregation-induced emission.
These results suggest that the probe TPE-V has an excellent
specificity to viscosity. In addition, the fluorescence intensity
of TPE-V under various pH values at 650 nm had no significant
These results exhibit that TPE-V is highly sensitive to detect of
viscosity.
Fluorescence lifetime is another way to validate the
sensitivity of the probe for viscosity detection and it is not
effected by the concentration, absorption, and emission
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4
intensity of the probe.
Therefore, we measured the
sensitivity of probe in different water-glycerol system by
fluorescence lifetime. As shown in Fig. 1c, the fluorescence
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changes (Fig. S6). These results indicate that TPE-V has change mitochondrial viscosity.
COMMUNICATION
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The fluorescence imaging
potential application in complex biological systems.
of TPE-V monitoring the mitochondrial viscosity changes are
shown in Fig. 4. When HeLa cells were treated with 10 μM
TPE-V, fluorescence intensity could be observed in red channel
and mitochondrial morphology exhibited tubule-like. While the
Hela cells were pre-incubated with 10 μM Mo or 10 μM Ny for
4
0 min, and then cultured with TPE-V for another 30 min, an
obvious fluorescence enhancement was obtained. Importantly,
obvious changes of mitochondria morphology from tubule
form to globular-like could be observed, which probably due to
the structural changes of mitochondria stimulated by Mo and
Ny. Moreover, the similar results were also observed in the
imaging experiments in NHA cells (Fig. S6). Differently, under
the same experimental conditions, the fluorescence intensity
in HeLa cells is obviously stronger than that in NHA, which
Fig. 2. Selectivity of TPE-V to viscosity. (a) Fluorescence spectra change of TPE-V
in 99% V/V glycerol solution and other representative bioactive molecules in PBS
buffer (10 mM, pH=7.4). The probe was treated with these molecules for 30 min.
(
b) Fluorescence intensity of TPE-V at 650 nm after 30 min incubation with
representative bioactive molecules in PBS buffer. 1. BSA, 2. CaCl
2
CuSO , 5. Cys, 6.GSH, 7. H , 8. HClO, 9. Na S, 10. NaHSO , 11. FeSO
, 3. MgCl
4
2
, 4,
2
4
2
O
2
2
3
, 12. ZnCl
,
3. KI, 14. Hcy, 15. DTBP, 16. NaOAc, 17. NaF, 18. TBHP, 19. NaCl, 20. Only probe
1
TPE-V, 21. TPE-V in 99% V/V glycerol solution. λex = 460 nm.
Encouraged by the above desirable attributes of TPE-V
,
we further evaluated the capability of TPE-V to monitor the illustrates that the mitochondrial viscosity in HeLa cells is
viscosity changes in living cells. Initially, the toxicity of TPE-V to higher than in NHA cells. These results suggest that TPE-V can
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6
living cells were examined by MTT assays. As shown in Fig. detect the viscosity changes in mitochondrial of living cells
S7, the survival rate of HeLa and NHA cells were more than sensitively.
80%, demonstrating that TPE-V has almost no toxicity to HeLa
and NHA cells and can be used for cell imaging.
Considering the overall positive charge of TPE-V, we
reasoned that the probe may be accumulated in the
mitochondria. Therefore, the intracellular distribution of TPE-V
was further studied by colocalization experiment (Fig. 3). HeLa
cells were cultured with TPE-V (10 μM) for 30 min, and then
cultured with 500 nM Mito-Tracker Green (MTG, the
commercial mitochondrial dye) for another 10 min. The
imaging results indicated that the green channel of MTG and
red channel of TPE-V can overlap well. The Pearson’s
correlation coefficients were calculated as high as 0.95.
Moreover, the variations of intensity profiles in green and red
channel exhibited a tendency toward synchrony. These results
suggest that TPE-V has good membrane permeability and
primarily accumulated in mitochondrial.
Fig. 4. The fluorescence imaging of HeLa cells. (a1-a3) Images of HeLa cells
stained with 10 μM TPE-V for 30 min and then treated with 0.4 % trypan blue for
anothr 5 min. (b1-b3) HeLa cells exposed to monensin (10 μM), and then
incubated with TPE-V (10 μM) and trypan blue (0.4 %). (c1-c3) Cells pre-treated
with nystatin (10 μM), and then treated with TPE-V (10 μM) and trypan blue (0.4
%
). (a1-c1) Bright-field images of HeLa cells. (a2-c2) Fluorescence images of HeLa
cells in red channel. (a3-c3) the overlay of bright-field and red channel. λex = 488
nm, λem = 570−620 nm. Scale bar: 20 μm.
As reported that inflammation can stimulate the increase
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0
of viscosity. Lipopolysaccharide (LPS), a cell wall ingredient
of gram-negative bacteria, has been verified to trigger cells to
Fig. 3. The colocalization fluorescence imaging of HeLa cells co-treated with (a)
Mito-Tracker Green (500 nM) and (b) TPE-V (10 μM) under excitation at 488 nm.
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1
produce inflammation. Therefore, LPS induced cells is a well-
(
channel and red channel. (e) Intensity profile of two channels. Green channel:
c) The merged image of (a) and (b). (d) The intensity scatter plot of green
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2
established model for inflammation study. To further study
the feasibility of TPE-V to detect viscosity changes in
inflammation cell models, LPS was used to establish
inflammatory model in NHA and HeLa cells (Fig. 5). When
treated with TPE-V (10 μM), NHA cells displayed almost no
fluorescence. However, NHA pre-treated with LPS (20 μM),
and then incubated with TPE-V showed marked fluorescence
enhancement. The similar results can also be demonstrated in
λ
em = 500−550 nm. Red channel: λem = 570−620 nm nm. Scale bar: 20 μm.
Dysfunction of mitochondrial may directly lead to several
human diseases accompanied by an increase of mitochondrial
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matrix viscosity.
To verify whether TPE-V could detect
mitochondrial viscosity variations in living cells by fluorescence
imaging, monensin (Mo) and nystatin (Ny) were used to
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HeLa cells. We further recorded the fluorescence lifetime
In conclusion, we have designed a highly sensitive
images of TPE-V with or without the LPS stimulations in NHA viscosity fluorescent probe with near-infrared emission by
and HeLa cells (Figure 6). After the LPS treatment, observable using TPE moiety and an indole salt moiety as rotational
much longer fluorescence lifetime were observed in NHA and groups. TPE-V exhibited a large “off-on” fluorescence response
HeLa cells. In this process, mitochondrial viscosity of NHA cells (about 100-fold enhancement) from water to 99 %V/V glycerol
increased from about 50 to 600 cp and HeLa cells increased with a large stokes shift (about 190 nm). Moreover, TPE-V
from about 70 to 600 cp. These studies reveal that TPE-V is displayed an excellent sensitivity (<15 cP) and specificity to
suitable for detecting viscosity in cell inflammatory model.
viscosity. More importantly, TPE-V successfully realized the
detection of mitochondria viscosity changes and vividly
showed the influence of LPS on mitochondria viscosity. We
expect that the unique viscosity probe TPE-V will be further
applied to disease research as a powerful tool. Furthermore,
the design strategy may be extended for various functional
fluorescent probe with extraordinary optical properties.
Conflicts of interest
The authors declare no competing financial interest.
ACKNOWLEDGMENT
This work was financially supported by NSFC (21472067, 21672083
，
21877048), Taishan Scholar Foundation (TS 201511041), and the
startup fund of the University of Jinan (309-10004).
Notes and references
1
2
K. Luby-Phelps, Curr. Opin. Cell Biol., 1994, 6, 3-9.
J. S. Goodwin, K. R. Drake, C. L. Remmert and A. K. Kenworthy,
Biophys. J., 2005, 89, 1398-1410.
3
4
K. Luby-Phelps, Int. Rev. Cytol., 1999, 192, 189-221.
G. D. Lowe, M. M. Drummond, A. R. Lorimer, I. Hutton, C. D.
Forbes, C. R. Prentice and J. C. Barbenel, Brit. Med., 1980, 280,
Fig. 5. The fluorescence imaging of NHA and HeLa cells. (a1-a3) Images of NHA
cells stained with 10 μM TPE-V for 30 min and then treated with 0.4 % trypan
blue for 5 min. (b1-b3) NHA cells exposed to LPS (20 μM), and then incubated
with TPE-V (10 μM) and trypan blue (0.4 %). (c1-c3) Images of HeLa cells stained
with 10 μM TPE-V for 30 min and then treated with 0.4 % trypan blue for 5 min.
6
73-674.
5
6
K. Scheuer, A. Maras, W. F. Gattaz, N. Cairns, H. Förstl and W. E.
Müller, Dement. Geriatr. Cogn., 1996, 7, 210-214.
G. J. Bosman, I. G. Bartholomeus and W. J. de Grip, Gerontology,
1991, 37, 95-112.
A. E. Raine, Lancet, 1988, 1, 97-100.
M. K. Kuimova, S. W. Botchway, A. W. Parker, M. Balaz, H. A.
Collins, H. L. Anderson, K. Suhling and P. R. Ogilby, Nat. Chem.,
(
d1-d3) HeLa cells pretreated with LPS, and then treated with TPE-V and trypan
blue (0.4 %). (a1-d1) Bright-field images of NHA and HeLa cells. (a2-d2)
Fluorescence images of NHA and HeLa cells in red channel. (a3-d3) the overlay of
bright-field and red channel. λex = 488 nm, λem = 570−620 nm nm. Scale bar: 20
μm.
7
8
2
009, 1, 69-73.
9
1
J. A. Dix and A. S. Verkman, Biophys. J., 1990, 57, 231-240.
0 K. Luby-Phelps, S. Mujumdar, R. B. Mujumdar, L. A. Ernst, W.
Galbraith and A. S. Waggoner, Biophys. J., 1993, 65, 236-242.
1 M. K. Kuimova, G. Yahioglu, J. A. Levitt and K. Suhling, J. Am.
Chem. Soc., 2008, 130, 6672-6673.
1
1
1
2 P. Maechler and C. B. Wollheim, Nature, 2001, 414, 807-812.
3 P. Mecocci, M. F. Beal, R. Cecchetti, M. C. Polidori, A. Cherubini,
F. Chionne, L. Avellini, G. Romano and U. Senin, Mol. Chem.
Neuropathol., 1997, 31, 53-64.
1
1
4 I. Lopez-Duarte, T. T. Vu, M. A. Izquierdo, J. A. Bull and M. K.
Kuimova, Chem. Commun, 2014, 50, 5282-5284.
5 L. Wang, Y. Xiao, W. Tian and L. Deng, J. Am. Chem. Soc., 2013,
135, 2903-2906.
Figure 6. The fluorescence lifetime imaging of TPE-V in HeLa and NHA cells. (a) Images
of NHA cells stained with 10 μM TPE-V for 30 min. (b) NHA cells exposed to 20 μM LPS 16 L. Li, K. Li, M.-Y. Li, L. Shi, Y.-H. Liu, H. Zhang, S.-L. Pan, N. Wang,
for 40 min, and then incubated with 10 μM TPE-V for another 30 min. (c) Images of
HeLa cells stained with 10 μM TPE-V for 30 min. (d) HeLa cells pretreated with 20 μM 17 M. Ren, K. Zhou, L. Wang, K. Liu and W. Lin, Sens. Actuators, B.,
Q. Zhou and X. Yu, Anal. Chem., 2018, 90, 5873-5878.
LPS for 40 min, and then treated with 10 μM TPE-V for another 30 min.
2018, 262, 452-459.
1
1
8 H. Chen, B. Dong, Y. Tang, W. Lin, Acc. Chem. Res., 2017, 50,
1
410-1422.
9 Y. Hong, J. W. Y. Lam and B. Z. Tang, Chem. Commun., 2009, 45,
4
| J. Name., 2012, 00, 1-3
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Journal Name
332-4353.
COMMUNICATION
4
P. Mazat, T. Letellier, J. Dachary-Prigent, G. C. Solaini and R.
Rossignol, J. Bioenerg. Biomembr., 2005, 37, 207-225.
28 A. C. Souza, F. S. Machado, M. R. Celes, G. Faria, L. B. Rocha, J. S.
Silva and M. A. Rossi, Transbound. Emerg. Dis., 2005, 52, 230-
237.
2
2
2
0 J. Mei, Y. Hong, J. W. Y. Lam, A. Qin, Y. Tang and B. Z. Tang, Adv.
Mater., 2014, 26, 5429-5479.
1 Y. Hong, J. W. Y. Lam and B. Z. Tang, Chem. Soc. Rev., 2011, 40,
5361-5388.
2 J. Chen, C. C. W. Lam, J. W. Y. Lam, Y. Dong, S. M. F. Lo, I. D. 29 Z. Yang, Y. He, J. H. Lee, N. Park, M. Suh, W. S. Chae, J. Cao, X.
Williams, D. Zhu, B. Z. Tang, Chem. Mater. 2003, 15, 1535-1546.
3 T. Förster, G. Hoffmann, Z. Phys. Chem., 1971, 75, 63-76.
4 P. I. Bastiaens and A. Squire, Trends Cell Biol., 1999, 9, 48-52.
Peng, H. Jung and C. Kang, J. Am. Chem. Soc., 2013, 135, 9181-
9185.
30 O. J. Stone, Med. Hypotheses, 1988, 25, 141-145.
2
2
2
5 M. A. Haidekker, T. P. Brady, D. Lichlyter and E. A. Theodorakis, 31 M. Kitazawa, S. Oddo, T. R. Yamasaki, K. N. Green and F. M.
Bioorg. Chem., 2005, 33, 415-425. Laferla, J. Neurosci., 2005, 25, 8843-8853.
6 L. He, W. Lin, Q. Xu, and H. Wei. Chem. Comm., 2015, 51, 1510- 32 F. Yuan, J. Chen, P.-P. Sun, S, Guan and J. Xu, J. Biomed. Sci.
2
2
1513.
2013, 20.
7 A. M. Aleardi, G. Benard, O. Augereau, M. Malgat, J. C. Talbot, J.
This journal is © The Royal Society of Chemistry 20xx
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We designed a new near-infrared emission fluorescent probe with multi-rotatable moieties
for imaging of mitochondrial viscosity in inflammatory cell model.