Recently, some studies have focused on dendrimer nanopolymers as a magnetic resonance imaging (MRI) contrast agent or a vehicle for gene and drug delivery. Considering the suitable properties of these materials, they are appropriate candidates for coating iron-oxide nanoparticles which are applied in magnetic hyperthermia. To the best of our knowledge, the novelty of this study is the investigation of fourth-generation dendrimer-coated iron-oxide nanoparticles (G4@IONPs) in magnetic hyperthermia and MRI. IONPs were synthesized via co-precipitation and coated with the fourth generation (G4) of polyamidoamine dendrimer. The cytotoxicity of G4@IONPs with different concentrations was assessed in a human breast cancer cell line (MCF7) and human fibroblast cell line (HDF1). Hemolysis and stability of G4@IONPs were investigated, and in addition, the interaction of these particles with MCF7 cells was assessed by Prussian blue staining. Heat generation and specific absorption rate (SAR) were calculated from measurement and simulation results at 200 and 300 kHz. MCF7 and HDF1 cells were incubated with G4@IONPs for 2 h and then put into the magnetic coil for 120 min. Relaxometry experiments were performed with different concentrations of G4@IONPs with T1- and T2-weighted MR images. The TEM results showed that G4@IONPs were 10 ± 4 nm. The in vitro toxicity assessments showed that synthesized nanoparticles had low toxicity. The viability of MCF7 cells incubated with G4@IONPs decreased significantly after magnetic hyperthermia. In addition, MR imaging revealed that G4@IONPs improved transverse relaxivity (r2) significantly. Our results encouraged the future application of G4@IONPs in magnetic hyperthermia and MR imaging.

中文翻译：

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乳腺癌细胞的磁热疗和使用树枝状聚合物涂层氧化铁纳米粒子进行的 MRI 松弛测量。

最近，一些研究重点关注树枝状纳米聚合物作为磁共振成像（MRI）造影剂或基因和药物输送的载体。考虑到这些材料的合适特性，它们是用于磁热疗的氧化铁纳米粒子涂层的合适候选者。据我们所知，这项研究的新颖之处在于第四代树枝状聚合物涂层氧化铁纳米颗粒（G4@IONPs）在磁热疗和MRI中的研究。IONPs 通过共沉淀法合成，并涂有第四代 (G4) 聚酰胺胺树枝状聚合物。在人乳腺癌细胞系（MCF7）和人成纤维细胞系（HDF1）中评估了不同浓度的G4@IONPs的细胞毒性。研究了 G4@IONPs 的溶血和稳定性，此外，通过普鲁士蓝染色评估了这些颗粒与 MCF7 细胞的相互作用。根据 200 kHz 和 300 kHz 的测量和模拟结果计算发热和比吸收率 (SAR)。MCF7和HDF1细胞与G4@IONPs一起孵育2小时，然后放入磁力线圈中120分钟。使用不同浓度的 G4@IONPs 和 T1 和 T2 加权 MR 图像进行松弛测量实验。TEM结果显示G4@IONPs的尺寸为10±4 nm。体外毒性评估表明，合成的纳米颗粒具有较低的毒性。磁热热后，与 G4@IONPs 一起孵育的 MCF7 细胞的活力显着下降。此外，MR 成像显示 G4@IONPs 显着提高了横向弛豫率 (r2)。我们的结果鼓励了 G4@IONPs 在磁热疗和 MR 成像中的未来应用。