Preparation of MRI-Visible Gadolinium Methacrylate Nanoparticles with Low Cytotoxicity

Preparation of MRI-visible gadolinium methacrylate nanoparticles with low cytotoxicity and high magnetic relaxivity

Xu Dong1, Yuxue Ding1, Pan Wu1, Changchun Wang1, and Christian G. Schäfer1,*

1 State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, 220 Handan Road, Shanghai 200433, China

Figure S1 Zeta potential measurements of poly(Gd(MAA)3) nanoparticles prepared in H2O, with a monomer content of 0.5 wt%.

Figure S2 FT-IR spectra of Gd(MAA)3, poly(Gd(MMA)3) nanoparticles and polyMAA (left) and comparison of the FT-IR spectra of poly(Gd(MMA)3) nanoparticles and polyMAA.

Analysis of the FT-IR spectra [1, 2]:

In the curve for the Gd(MAA)3 powder, the sharp absorption peak at 1643 cm−1 can be attributed to the stretching vibration of C=C. The sharp absorption peaks at 1533 cm−1 and 1417 cm−1 can be assigned to the anti-symmetric and symmetric stretching vibrations of COO. The characteristic bands at 953–945 cm−1 and 844–825 cm−1 can be clearly assigned to the C-H out of plane bending vibration.

In the curve for poly(Gd(MAA)3) obtained by dispersion polymerization in water, the C=C peaks at 1643 cm−1 observed for the Gd(MAA)3 powder have disappeared. Meanwhile, the peaks at 1533 cm−1 and 1417 cm−1 become broader than that for Gd(MAA)3 powder. In the curve for polyMAA the characteristic absorption band appeared at 1720 cm−1, which can be assigned to the stretching vibrations of -COOH of polyMAA. For polyGd(MAA)3 the stretching vibration shifted to 1533 cm−1, and a new sharp peak 1417 cm−1 appeared, which could be attributed to the linkage between polyMAA and GdIII. These changes confirm the successful formation of poly(Gd(MAA)3) by dispersion polymerization.

References

[1] Wen S, Zhou Y, Yao L, Zhang L, Chan TW, Liang Y, Liu L (2013) In situ self-polymerization of unsaturated metal methacrylate and its dispersion mechanism in rubber-based composites, Thermochim Acta 571:15-20.

[2] Wu W, Zhai Y, Zhang Y, Ren W (2014) Mechanical and microwave absorbing properties of in situ prepared hydrogenated acrylonitrile–butadiene rubber/rare earth acrylate composites, Composites Part B: Engineering 56:497-503.

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