Magnetic nanoparticles in general, and iron oxide nanoparticles in particular, have been studied extensively during the past 20 years for numerous biomedical applications. The main applications of these nanoparticles are in magnetic resonance imaging (MRI), magnetic targeting, gene and drug delivery, magnetic hyperthermia for tumor treatment, and manipulation of the immune system by macrophage polarization for cancer treatment. Recently, considerable attention has been paid to magnetic particle imaging (MPI) because of its better sensitivity compared to MRI. In recent years, MRI and MPI have been combined as a dual or multimodal imaging method to enhance the signal in the brain for the early detection and treatment of brain pathologies. Because magnetic and iron oxide nanoparticles are so diverse and can be used in multiple applications such as imaging or therapy, they have attractive features for brain delivery. However, the greatest limitations for the use of MRI/MPI for imaging and treatment are in brain delivery, with one of these limitations being the brain-blood barrier (BBB). This review addresses the current status, chemical compositions, advantages and disadvantages, toxicity and most importantly the future directions for the delivery of iron oxide based substances across the blood-brain barrier for targeting, imaging and therapy of primary and metastatic tumors of the brain.

中文翻译：

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磁性氧化铁纳米粒子，用于成像，靶向和治疗脑部原发性和转移性肿瘤。

在过去的20年中，广泛地对磁性纳米粒子，尤其是氧化铁纳米粒子进行了广泛的生物医学应用研究。这些纳米粒子的主要应用是磁共振成像（MRI），磁性靶向，基因和药物递送，用于肿瘤治疗的磁热疗以及通过巨噬细胞极化对免疫系统的操纵以用于癌症治疗。近年来，由于磁性粒子成像（MPI）的灵敏度高于MRI，因此已经引起了人们的极大关注。近年来，MRI和MPI已被结合为一种双模式或多模式成像方法，以增强大脑中的信号，从而早期检测和治疗脑部疾病。由于磁性和氧化铁纳米粒子种类繁多，可用于多种应用（例如成像或治疗），因此它们具有吸引人的大脑输送功能。但是，使用MRI / MPI进行成像和治疗的最大局限性在于大脑的输送，其中之一就是脑血屏障（BBB）。这篇综述阐述了通过血脑屏障递送氧化铁基物质以靶向，成像和治疗脑部原发性和转移性肿瘤的现状，化学成分，优缺点，毒性以及最重要的未来方向。这些限制之一是脑血屏障（BBB）。这篇综述阐述了通过血脑屏障递送氧化铁基物质以靶向，成像和治疗脑部原发性和转移性肿瘤的现状，化学成分，优缺点，毒性以及最重要的未来方向。这些限制之一是脑血屏障（BBB）。这篇综述阐述了通过血脑屏障递送氧化铁基物质以靶向，成像和治疗脑部原发性和转移性肿瘤的现状，化学成分，优缺点，毒性以及最重要的未来方向。