Silica-Coated Nonstoichiometric Nano Zn-Ferrites for Magnetic Resonance Imaging and Hyperthermia Treatment
Silica-Coated Nonstoichiometric Nano Zn-Ferrites for Magnetic Resonance Imaging and Hyperthermia Treatment
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用于磁共振成像和热疗的二氧化硅涂层非化学计量纳米锌铁氧体
DOI：
10.1002/adhm.201600725
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发表时间：
2016-10-01
影响因子：
10
通讯作者：
Pratsinis, Sotiris E.
中科院分区：
文献类型：
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作者：
Starsich, Fabian H. L.;Sotiriou, Georgios A.;Pratsinis, Sotiris E.
纳米材料的大规模且可重复的合成受到高度重视，以成功转化为临床。火焰气溶胶技术已被证实能够制造高达 kg·h(-1) 的高纯度材料（例如光导），本文探索了用于制备原位涂覆纳米薄 SiO2 层的高磁性、非化学计量的铁氧体锌 (Zn0.4Fe2.6O4) 纳米粒子。重点是它们作为磁性多功能治疗诊断剂的适用性，分析其磁共振成像 (MRI) 的 T2 对比增强能力及其磁热疗性能。初级颗粒尺寸严格控制在 5 至 35 nm 范围内，评估其对磁性能、MRI 弛豫率和磁加热性能的影响。最重要的是，在火焰前驱体溶液中添加锌有利于尖晶石锌铁氧体晶体的生长，该晶体表现出比通常在火焰中制备的氧化铁更优异的磁性。这些特性可产生强 MRI T2 造影剂，如 4.7 T 小动物 MRI 扫描仪所示，并通过交变磁场实现更有效的加热。此外，通过将 Zn0.4Fe2.6O4 纳米颗粒悬浮液注射到猪肉组织中，可以在临床相关浓度下获取 MR 图像。此外，纳米薄的 SiO2 壳有利于聚合物的功能化，从而提高了治疗诊断系统的生物相容性。
Large-scale and reproducible synthesis of nanomaterials is highly sought out for successful translation into clinics. Flame aerosol technology with its proven capacity to manufacture high purity materials (e.g., light guides) up to kg h(-1) is explored here for the preparation of highly magnetic, nonstoichiometric Zn-ferrite (Zn0.4Fe2.6O4) nanoparticles coated in situ with a nanothin SiO2 layer. The focus is on their suitability as magnetic multifunctional theranostic agents analyzing their T2 contrast enhancing capability for magnetic resonance imaging (MRI) and their magnetic hyperthermia performance. The primary particle size is closely controlled from 5 to 35 nm evaluating its impact on magnetic properties, MRI relaxivity, and magnetic heating performance. Most importantly, the addition of Zn in the flame precursor solution facilitates the growth of spinel Zn-ferrite crystals that exhibit superior magnetic properties over iron oxides typically made in flames. These properties result in strong MRI T2 contrast agents as shown on a 4.7 T small animal MRI scanner and lead to a more efficient heating with alternating magnetic fields. Also, by injecting Zn0.4Fe2.6O4 nanoparticle suspensions into pork tissue, MR-images are acquired at clinically relevant concentrations. Furthermore, the nanothin SiO2 shell facilitates functionalization with polymers, which improves the biocompatibility of the theranostic system.