Polypyrrole-Coated Magnetite Vortex Nanoring for Hyperthermia-Boosted Photothermal/Magnetothermal Tumor Ablation Under Photoacoustic/Magnetic Resonance Guidance

Jianfeng Bao; Shuangshuang Guo; Xiangyang Zu; Yuchuan Zhuang; Dandan Fan; Yong Zhang; Yupeng Shi; Zhenyu Ji; Jingliang Cheng; Xin Pang

doi:10.3389/fbioe.2021.721617

Polypyrrole-Coated Magnetite Vortex Nanoring for Hyperthermia-Boosted Photothermal/Magnetothermal Tumor Ablation Under Photoacoustic/Magnetic Resonance Guidance

Front Bioeng Biotechnol. 2021 Jul 30:9:721617. doi: 10.3389/fbioe.2021.721617. eCollection 2021.

Authors

Affiliations

¹ Functional Magnetic Resonance and Molecular Imaging Key Laboratory of Henan Province, Department of Magnetic Resonance Imaging, First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China.
² Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China.
³ College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, China.
⁴ Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, United States.

Abstract

Photothermal/magnetothermal-based hyperthermia cancer therapy techniques have been widely investigated, and associated nanotechnology-assisted treatments have shown promising clinical potentials. However, each method has some limitations, which have impeded extensive applications. For example, the penetration ability of the photothermal is not satisfactory, while the heating efficiency of the magnetothermal is very poor. In this study, a novel magnetite vortex nanoring nanoparticle-coated with polypyrrole (denoted as nanoring Fe₃O₄@PPy-PEG) was first synthesized and well-characterized. By combining photothermal and magnetothermal effects, the performance of the dual-enhanced hyperthermia was significantly improved, and was thoroughly examined in this study. Benefiting from the magnetite vortex nanoring and polypyrrole, Fe₃O₄@PPy-PEG showed excellent hyperthermia effects (SAR = 1,648 Wg^-1) when simultaneously exposed to the alternating magnetic field (300 kHz, 45 A) and near-infrared (808 nm, 1 W cm^-2) laser. What is more, nanoring Fe₃O₄@PPy-PEG showed a much faster heating rate, which can further augment the antitumor effect by incurring vascular disorder. Besides, Fe₃O₄@PPy-PEG exhibited a high transverse relaxation rate [60.61 mM^-1 S^-1 (Fe)] at a very low B₀ field (0.35 T) and good photoacoustic effect. We believe that the results obtained herein can significantly promote the development of multifunctional nanoparticle-mediated magnetic and photo induced efficient hyperthermia therapy.

Keywords: magnetic hyperthermia; magnetite vortex nanoring; multimodal imaging; photothermal hyperthermia; theranostics.