Supporting Information
Triple
Stimuli-Responsive
Polymers
Based
on
Pyrene-Functionalized
Poly(dimethylaminoethyl methacrylate): Synthesis, Self-Assembled Nanoparticles and
Controlled Release
Jie Dong, Ruichen Zhang, Xiaowei Zhan, Huai Yang, Siquan Zhu, Guojie Wang*
–––––––––
J. Dong, R. C. Zhang, Prof. G. J. Wang
School of Materials Science and Engineering, University of Science and Technology Beijing,
Beijing 100083, China
E-mail: guojie.wang@mater.ustb.edu.cn
Prof. X. W. Zhan, Prof. H. Yang
Department of Materials Science and Engineering, College of Engineering, Peking University,
Beijing 100871, China
Prof. S. Q. Zhu
Beijing Tongren Hospital, Capital Medical University, Beijing 100069, China
–––––––––
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FTIR spectra: Infrared spectroscopy was used to prove the reaction between the amine
groups and the carboxylic acid groups generated after UV irradiation. 10 mg of P1 and 1 mL
of H2O were placed in a standard cuvette, while the solution was exposed to UV light (365
nm, 80 mW/cm2) under stirring for 40 min. Then the solvent was freeze-dried before FTIR
measurements. Fig. S1 clearly shows that the carbon-nitrogen vibration peak (from the amino
groups) at 2800 cm-1decreased and a large carbon-nitrogen vibration peak (from the
ammonium groups)
[S1]
increased at 3400 cm-1 after UV irradiation. The decrement of the
peak at 2800 cm-1 and the increase of the peak at 3400 cm-1 proved the reaction between the
amine groups and the carboxylic acid groups after UV irradiation.
Before irradiation
-N(CH3)2
COO-CH2-CH2-N
After irradiation
-N+(CH3)2-CO
Figure S1. FTIR spectra of the pyrene-functionalized PDMAEMA (P1) before and after UV
irradiation.
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a)
e)
b)
f)
T/C
T/C
i)
g)
c)
g)
T/C
k)
d)
h)
T/C
l)
Figure S2. Fluorescence emission spectra of the micellar solution loaded with Nile Red (ex =
350 nm) under UV irradiation for different time: a) P1; b) P2; c) P3; d) P4; at different
temperature: e) P1; f) P2; g) P3; h) P4; at different pH: i) P1; j) P2; k) P3; l) P4.
The appearance of fluorescence emission of NR at 647 nm suggests the occurrence of
nonradiative energy transfer (NRET) from excited pyrene to NR.
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a)
b)
c)
d)
Figure S3. UV-vis absorption spectra of the micellar solution (P1) loaded with DOX: a)
before stimulation; b) after 30 min UV irradiation; c) at pH 7.4, then pH 3, and then pH 10.
d) UV-vis absorption spectrum of the DOX·HCl solution (0.025 mg/mL).
Figure S3a, b, and c show the UV-vis absorption spectra of the micellar solution (P1) loaded
with DOX, where curve 1 is the UV-vis absorption spectrum of the micellar solution loaded
with DOX composed of that of pyrene and that of DOX, curve 2 and 3 are the absorption
spectra of the pyrene and DOX respectively, divided from curve 1. Figure S3d shows the UVvis absorption spectrum of DOX with a concentration of 0.025 mg/mL. From the curve 3 in
Fig. S3a and the spectrum of DOX in Fig. S3d, it can be calculated that the concentration of
the DOX loaded in micelle is about 0.014 mg/mL. From the curve 3 in Fig. S3a and the curve
3 in Fig. S3b, it can be obtained that upon UV irradiation, about 90% of the loaded DOX was
released. From the curve 3 in Fig. S3a and the curve 3 in Fig. S3c, it can be obtained that at
pH3, about 88% of the loaded DOX was released.
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b)
a)
Figure S4.
UV-Vis absorption spectra of: a) 1-(hydroxymethyl) pyrene in CH2Cl2
(1.11×10-3 mg/mL). b) P1 in water (9.89×10-3 mg/mL), P2 in water (9.89×10-3 mg/mL), P3
in water (1.12×10-2 mg/mL), P4 in water (1.00×10-2 mg/mL).
The functionalization degree of the P1, P2, P3 and P4 could be calculated to be 4.1%, 7.8%,
11.0% and 13.0% from the data of Figure S4.
Figure S5. UV-vis absorption spectra of the micellar solution (P1) under UV irradiation for
different time.
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Figure S6.
Fluorescence emission spectra of NR in CH2Cl2 under UV irradiation for
different time (365 nm, 80 mWcm-2).
Figure S6 shows that the emission intensity of NR decreased insignificantly upon UV
irradiation.
a)
b)
Figure S7. UV-Vis absorption spectra (a) and fluorescence emission spectra (b) of NR in
water at different pH and in micellar solution at pH 7.
Figure S7 shows that negligible absorption and fluorescence emission of NR could be
observed in water since the hydrophobic NR could hardly be dissolved in water. The
fluorescence emission remained almost unchanged when pH changed from 7 to 3 or 11, as
indicated that the fluorescence of NR was not dependent on pH.
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a)
b)
Figure S8. UV-Vis absorption spectra (a) and fluorescence emission spectra (b) of DOX·
HCl in water under UV irradiation for different time (365 nm, 10 mWcm-2).
Figure S8 shows that the absorption and emission intensity of DOX decreased
insignificantly upon UV irradiation.
Reference
[S1] H. Wu, J. Dong, C. C. Li, Y. B. Liu, N. Feng, L. P. Xu, X. W. Zhan, H. Yang, G. J.
Wang, Chem. Commun. 2013, 49, 3516.
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