Department of Radiology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
Department of Radiology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; Thayer School of Engineering, Dartmouth College, Hanover, NH, USA.
J Magn Reson. 2024 May;362:107690. doi: 10.1016/j.jmr.2024.107690. Epub 2024 Apr 25.
This research report describes a novel surface dielectric resonator (SDR) with a flexible connector for in vivo electron paramagnetic resonance (EPR) spectroscopy. Contrary to the conventional cavity or surface loop-gap resonators, the newly developed SDR is constructed from a ceramic dielectric material, and it is tuned to operate at the L-band frequency band (1.15 GHz) in continuous-wave mode. The SDR is designed to be critically coupled and capable of working with both very lossy samples, such as biological tissues, and non-lossy materials. The SDR was characterized using electromagnetic field simulations, assessed for sensitivity with a B field-perturbation method, and validated with tissue phantoms using EPR measurements. The results showed remarkably higher sensitivity in lossy tissue phantoms than the previously reported multisegment surface-loop resonators. The new SDR can provide potential new insights for advancements in the application of in vivo EPR spectroscopy for biological measurements, including clinical oximetry.
本研究报告介绍了一种新型的带有柔性连接器的表面介电谐振器 (SDR)，用于体内电子顺磁共振 (EPR) 光谱学。与传统的腔或表面环形缝隙谐振器不同，新开发的 SDR 由陶瓷介电材料构成，调谐至连续波模式的 L 波段（1.15GHz）工作。SDR 设计为临界耦合，能够与非常有损耗的样品（如生物组织）和无损耗材料一起工作。使用电磁场模拟对 SDR 进行了表征，使用 B 场扰动向灵敏度进行了评估，并通过 EPR 测量使用组织体模进行了验证。结果表明，在有损耗的组织体模中，灵敏度显著高于之前报道的多段表面环形谐振器。新的 SDR 可为体内 EPR 光谱学在生物测量中的应用提供新的见解，包括临床血氧测定法。
