The sensitivity of an electron paramagnetic resonance (EPR) spectrometer is one of the most important aspects for productive biomedical EPR studies. The microwave resonator is a key element for achieving high sensitivity with EPR in living subjects. Currently, there are three types of resonators available at the EPR Center, allowing optimal sensitivity to be achived for a wide range of in vivo measurements.

Surface-coil resonators

These resonators have been especially productive, facilitating localized measurements without acute invasion. We  have used external loop resonators (ELR) to measure oxygen-sensitive paramagnetic samples such as microcrystals of lithium phthalocyanine (LiPc) implanted at the site of interest. This can provide very useful information on oxygen-dependent physiological and pathological processes.

Whole-body loop-gap resonators

Implantable resonator