Advanced Surface Resonators for Electron Spin Resonance Measurement of Micro-size Single Crystals of Proteins

Electron Spin Resonance (ESR) is a spectroscopic method that is used in many fields of science, including biology, chemistry and material science. ESR measurement of single crystals of proteins is a powerful tool to obtain electron structural information about proteins. Conventional ESR machines lack the sensitivity to measure single crystal proteins smaller than ~1mm. To solve this problem we developed several microwave resonators that are able to acquire signal from micro-crystals, while adjusting each resonator`s design for a specific sample size. We present experimental results of ESR imaging compared to simulation, along with ESR spectra of single microcrystal proteins. Employment of the novel resonators in unexplored micro-crystals may lead to a more complete picture of biological phenomena and to the development of new drugs and bio-inspired molecular machines.