Development of biocompatible coatings for magnetic nanoparticles

目前，磁性颗粒的唯一批准的应用是作为磁共振成像（MRI）中的造影剂。然而，这些粒子具有巨大的未开发潜力。例如，它们可以用于许多治疗应用，包括磁靶向抗癌治疗或磁控药物递送到难以递送高效药物的区域（例如眼睛）而不会对非靶向器官产生严重的负面副作用。为了实现治疗性磁靶向，我们计划制备具有专门设计的涂层的磁铁矿纳米颗粒，这些涂层使它们具有高稳定性，良好的生物相容性，以及附着于许多不同分子（如抗体，肽，荧光染料和药物）的“钩”。这些磁性纳米颗粒将单独进行评估，并额外封装在更大的磁性微球中。这些微球的均匀尺寸使它们在流过患者血流时以可预测的方式对外部磁场做出反应。目前可用的无毒微球缺少这种可预测性，因为它们是许多不同尺寸的混合物。为了证实我们的策略的成功，磁性纳米颗粒和微球将在细胞培养和显微镜实验中进行评估，然后是磁靶向的体内眼模型。

Currently, the only approved application of magnetic particles is as contrast agents in magnetic resonance imaging (MRI). These particles, however, have great untapped potential. They, for example, could be used in many therapeutic applications including magnetically targeted anticancer therapy or magnetically controlled drug delivery to areas where it is difficult to deliver highly potent drugs (such as the eye) without having serious negative side effects on non-targeted organs. To enable therapeutic magnetic targeting, we plan to prepare magnetite nanoparticles with purposefully designed coatings that give them high stability, good biocompatibility, and a "hook" to attach to many different molecules such as antibodies, peptides, fluorescent dyes and drugs. These magnetic nanoparticles will be evaluated on their own and additionally encapsulated in larger magnetic microspheres. The uniform size of these microspheres makes them react in a predictable way to an external magnetic field while they flow through a patient's blood stream. Such predictability has been missing from currently available non-toxic microspheres as they are mixtures of many different sizes. To confirm the success of our strategy, magnetic nanoparticles and microspheres will be evaluated in cell culture and microscopy experiments, followed by an in vivo eye model of magnetic targeting.