Electronic Supplementary Information (ESI) for:
Fabrication of multifunctional ferric oxide nanoparticle for
tumor-targeted magnetic resonance imaging and precise
photothermal therapy with magnetic field enhancement
Contents
1. Additional Experimental Section
2. Additional Figures S1-S3
3. Additional Tables S1-S2
4. Additional References
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry B.This journal is © The Royal Society of Chemistry 2017
1 Additional Experimental Section
Synthesis of -Fe2O3 NPs: The -Fe2O3 NPs were synthesized by literature reported
strategy with slightly modification (see supporting information for details).S1,S2
Briefly, sodium oleate (1.5 mmol), FeCl3·6H2O (0.5 mmol), oleic acid (1.5 mmol),
and 1-octadecene (10 mL) were well mixed in a three necked flask. The mixture was
then heated to 150 °C under argon atmosphere for 1 h. Subsequently, the temperature
of mixture was increased to 300 °C and maintained at 300 °C for 2 h under argon gas
protection. After cooling to room temperature, the as-prepared iron oxide
nanoparticles (-Fe2O3 NPs) were collected by centrifugation (10000 rpm for 10 min),
and washed with ethanol (20 mL) for three times. Finally, the -Fe2O3 NPs were
redispersed in cyclohexane.
Synthesis of Fe2O3@PDA NPs: The PDA coated -Fe2O3 NPs (named as
Fe2O3@PDA NPs) were synthesized by water-in-oil microemulsion method.S3 Briefly,
0.65 mL Igepal CO-520 was added in 10 mL cyclohexane containing 10 mg oleic acid
stabilized -Fe2O3 NPs. After stirred for 20 min, 75 µL ammonium hydroxide (28 wt%
in water) were added into the mixture, and followed by ultrasonic treatment for 15
min. After stirred for another 30 min, 50 µL dopamine (DA) hydrochloride aqueous
solution (25 wt%) were injected into the above reaction mixture at a rate of 3 µL min-
1. After stirring for 24 h, the Fe2O3@PDA NPs were precipitated by ethanol, collected
by centrifugation (10 000 rpm for 10 min) and washed with ethanol and water (10 mL,
three times). Finally, the Fe2O3@PDA NPs were redispersed in water and dried by
vacuum evaporation.
Estimate the immobilized amount of affibody on Fe2O3@PDA NPs: Total amount
of immobilized affibody on Fe2O3@PDA NPs was estimated by UV-visible
spectroscopic analysis. Here, 100 mg Fe2O3@PDA NPs were incubated with 10 mL
affibody solution (1 mg mL-1 in PBS) at room temperature for 12 h. Subsequently, the
sample was stirred by ultrasound for 5 min, and centrifuged at 12 000 g for 30 min.
The absorbance of supernatant solution at 280 nm was measured by a
spectrophotometer. The total amount of unconjugated affibody was calculated by
corresponding calibration curve from pure affibody in PBS. Final, the weight
percentage of immobilized affibody on Fe2O3@PDA NPs was estimated by following
equation: wt/wt%=[(M0-M1)/MNPs]100%, here, M0 means initial mass of affibody
(i.e., 10 mg), M1 means the mass of unconjugated affibody, while MNPs means the
mass of Fe2O3@PDA NPs (i.e., 100 mg).
2 Additional Figures
Fig. S1 TGA curve of Fe2O3@PDA, ranging from room temperature to 800 °C at a
rate of 10 °C min−1.
Fig. S2 Hydrodynamic size of Fe2O3@PDA-affibody which were incubated in fresh
L-15 supplemented with 10% (v/v) FBS for 5 h.
Fig. S3 The amounts of Fe element in the NP-stained HL-7702 cells. The cells were
incubated with 100 g mL-1 Fe2O3@PDA-affibody and Fe2O3@PDA-PEG,
respectively.
Fig. S4 In vivo MR images of BALB/C mouse bearing SW620 tumor after
intravenous injection of 100 g mL-1 (Fe content) Fe2O3@PDA-affibody plus
an external MF (a) and corresponding data analysis of MR measurements with
or without external MF (b). The tumor site was indicated by white arrow. Error
bars mean standard deviations (n = 5, *P 0.05 from an analysis of variance
with Tukey’s post-test.).
Fig. S5 The digital photographs of different groups of mice after intravenous
treatments, which were treated with PBS only (Group I), PBS plus 808 nm NIR laser
irradiation (Group II), 10 mg kg-1 Fe2O3@PDA-Affibody plus 808 nm NIR laser
irradiation (Group III), 10 mg kg-1 Fe2O3@PDA-Affibody only (Group IV), 2 mg kg-1
Fe2O3@PDA-Affibody plus 808 nm NIR laser irradiation under the MF (Group V), 2
mg kg-1 Fe2O3@PDA-Affibody under MF (Group VI), 10 mg kg-1 Fe2O3@PDA-PEG
plus 808 nm NIR laser irradiation (Group VII), and 10 mg kg-1 Fe2O3@PDA-PEG
plus 808 nm NIR laser irradiation under MF (Group VIII) respectively. Inset shows
tumors collected from different groups of mice at the end of intravenous treatments
(day 14).
Fig. S6 Biodistribution of 100 g mL-1 (Fe content) Fe2O3@PDA-Affibody and
Fe2O3@PDA-PEG at 4 h post-intravenous injection, respectively. Error bars mean
standard deviations (n = 5, *P0.05, **P 0.01 or *** P 0.001 from an analysis of
variance with Tukey’s post-test.
Fig. S7 Histological changes of the nude mice after 30 days post-injection of (a) PBS
and (b) a single dose of Fe2O3@PDA-Affibody (10.0 mg kg-1) in PBS, respectively.
3 Additional Tables
Table S1 The zeta potentials and HDs of as-prepared NPs.
Zeta potential (mv) HD (nm)
Fe2O3@PDA -17.2 ± 1.5 85.9 ± 13.8
Fe2O3@PDA-PEG 0.7 ± 0.1 89.4 ± 15.7
Fe2O3@PDA-affibody 8.3 ± 0.6 92.3 ± 16.2
The NPs were dispersed in PBS. The TEM measurement indicates that the average
size of Fe2O3@PDA is 58.4 ± 7.6 nm in diameter.
Table S2 Hematology analysis of mice treated with and/or without Fe2O3@PDA-
affibody.
Hematological Units Control Treatment
WBC ×109/L 12.16 11.37
RBC ×1012/L 10.52 8.64
HGB g/L 165.00 152.00
MCV fL 42.40 43.70
MCH pg 16.80 17.20
MCHC g/L 348.00 335.00
PLT ×109/L 1254.00 1137.00
PDW fL 9.42 11.75
4 Additional References
[S1] Liu, F.; He, X.; Zhang, J.; Zhang, H.; Wang, Z. Employing Tryptone as a
General Phase Transfer Agent to Produce Renal Clearable Nanodots for Bioimaging.
Small 2015, 11, 3676-3685.
[S2] Xu, Z.; Shen, C.; Tian, Y.; Shi, X.; Gao, H. J. Organic phase synthesis of
monodisperse iron oxide nanocrystals using iron chloride as precursor. Nanoscale
2010, 2, 1027-1032.
[S3] Liu, F.; He, X.; Lei, Z.; Liu, L.; Zhang, J.; You, H.; Zhang, H.; Wang, Z. Facile
Preparation of Doxorubicin-Loaded Upconversion@Polydopamine Nanoplatforms for
Simultaneous In Vivo Multimodality Imaging and Chemophotothermal Synergistic
Therapy. Advanced Healthcare Materials 2015, 4, 559-568.