Kim Chan, Nan Jiyun, Nguyen Kim Tien, Park Jong-Oh, Choi Eunpyo, Kim Jayoung
Korea Institute of Medical Microrobotics, Gwangju 61186, Republic of Korea.
School of Mechanical Engineering, Chonnam National University, Gwangju 61186, Republic of Korea.
Sensors (Basel). 2025 Jan 23;25(3):665. doi: 10.3390/s25030665.
Active drug delivery systems for cancer therapy are gaining attention for their biocompatibility and enhanced efficacy compared to conventional chemotherapy and surgery. To improve precision in targeted drug delivery (TDD), actuating devices using external magnetic fields are employed. However, a key challenge is the inability to visually track magnetic drug carriers in blood vessels, complicating navigation to the target. Magnetic particle imaging (MPI) systems can localize magnetic carriers (MCs) but rely on bulky electromagnetic coils to generate a static magnetic field gradient, creating a field-free point (FFP) within the field of view (FOV). Also, additional coils are required to move the FFP across the FOV, limiting flexibility and increasing the system size. To address these issues, we propose a non-FFP-based, open-type RF coil system with a simplified structure composed of a Tx/Rx coil and a permanent magnet at the coil center, eliminating the need for an FFP. Furthermore, integrating a robotic arm for coil assembly enables easy adjustment of the FOV size and location. Finally, imaging tests with magnetic nanoparticles (MNPs) confirmed the system's ability to detect and localize a minimum mass of 0.3 mg (Fe) in 80 × 80 mm.
与传统化疗和手术相比，用于癌症治疗的主动药物递送系统因其生物相容性和更高的疗效而受到关注。为了提高靶向药物递送（TDD）的精度，采用了利用外部磁场的驱动装置。然而，一个关键挑战是无法在血管中直观地跟踪磁性药物载体，这使得导航到目标变得复杂。磁性粒子成像（MPI）系统可以定位磁性载体（MC），但依赖于笨重的电磁线圈来产生静磁场梯度，从而在视场（FOV）内产生一个无场点（FFP）。此外，还需要额外的线圈来在FOV内移动FFP，这限制了灵活性并增加了系统尺寸。为了解决这些问题，我们提出了一种基于非FFP的开放式射频线圈系统，其结构简化，由一个Tx/Rx线圈和位于线圈中心的永久磁铁组成，无需FFP。此外，集成一个用于线圈组装的机械臂可以轻松调整FOV的大小和位置。最后，使用磁性纳米颗粒（MNP）进行的成像测试证实了该系统能够在80×80mm范围内检测和定位最小质量为0.3mg（Fe）的物质。
