SBIR Phase I: Biocompatible tracers optimized for Magnetic Particle Imaging

这个小型企业创新研究 (SBIR) 第一阶段项目解决了磁粒子成像的基本问题，磁粒子成像是一种有前景的新型成像方式。 MPI 使用磁性纳米颗粒（示踪剂）生成信号，可用于对活体患者进行快速、安全、非侵入性 3D 成像。该问题与磁示踪剂有关：目前还没有适合 MPI 的商业示踪剂，部分原因是在使用现有生产方法时根本缺乏对示踪剂的物理和磁性特性的控制。我们通过确定任何 MPI 成像系统所需的示踪剂特性并开发一种生产具有受控/定制特性的粒子的方法来解决这个问题。拟议的研究旨在进一步提高我们产品的性能，既微调其物理特性，又提高其在生物环境中的稳定性。我们将通过开发一种用生物相容性外壳封装磁性颗粒的新工艺来提高示踪剂的稳定性和性能。我们还将通过开发一种新颖的过滤系统来进一步提高性能，以专门根据其对 MPI 的适用性（由其磁弛豫确定）来分离所需的示踪剂。该拟议项目的更广泛的影响/商业潜力是 MPI 的一项使能技术。目标是开发一种高性能解决方案，使临床 MPI 具有商业可行性。使用安全的氧化铁示踪剂的 MPI 可以降低心血管疾病治疗过程中患者的发病率，目前的成像方法（如 X 射线血管造影）严重依赖于碘造影剂的使用，尽管它们可能会导致患者（尤其是患有慢性肾病的患者）肾源性系统性纤维化。具有靶向示踪探针的 MPI 还为癌症诊断和治疗提供了重要前景，具有出色的信噪比和几乎完美的对比度（组织是抗磁性的，在 MPI 中不产生信号）。最后，MPI 的预计商业影响是巨大的：每年在医学成像示踪剂上花费数十亿美元，其中碘是最常用的示踪剂。最终，MPI 将规避碘造影剂的已知危害，有可能产生数十亿美元的示踪剂销售额。

This Small Business Innovation Research (SBIR) Phase I project addresses a fundamental problem with Magnetic Particle Imaging, a promising, yet new imaging modality. MPI uses magnetic nanoparticles (tracers) to generate a signal that can be used for fast, safe, non-invasive 3D imaging in living patients. The problem relates to the magnetic tracers: there are no existing commercial tracers that are suitable for MPI, due partly to a fundamental lack of control over the physical and magnetic properties of tracers when using existing methods of production. We have addressed this problem by identifying the desired tracer properties for any MPI imaging system and developing a method to produce particles with controlled/tailored properties. The proposed research is designed to further improve the performance of our product, both to fine-tune its physical characteristics and improve its stability in a biological environment. We will improve the stability and performance of our tracer agent by developing a new process for encapsulating the magnetic particles with a biocompatible shell. We will also further improve the performance by developing a novel filtering system to isolate desirable tracers based specifically on their suitability for MPI, as determined by their magnetic relaxation.The broader impact/commercial potential of this proposed project is an enabling technology for MPI. The goal is to develop a high performance solution that can make clinical MPI commercially viable. MPI using safe iron oxide tracers could reduce patient morbidity during the course of treatment for cardiovascular disease, where current imaging methods like x-ray angiography rely heavily on the use of iodinated contrast media even though they may cause nephrogenic systemic fibrosis in patients, especially those with chronic kidney disease. MPI with targeted tracer probes, also offers significant promise for cancer diagnosis and therapy, with outstanding signal to noise ratio and almost perfect contrast (tissue is diamagnetic and generates no signal in MPI). Finally, the projected commercial impact of MPI is significant: billions of dollars are spent on medical imaging tracers each year, with iodine the most commonly used tracer. Ultimately, MPI, which would circumvent a known hazard in iodine contrast agents, has the potential to generate billions in tracer sales.