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.