Compact Integrated EPR Spectrometer for Dynamic Nuclear Polarization

Project Summary Abstract The proposed research focuses on the development of a compact high field HF Electron Paramagnetic Resonance EPR spectrometer for DNP enhanced solid state magic angle spinning MAS NMR spectroscopy The spectrometer will allow researchers to record the EPR spectra and obtain valuable relaxation parameters of the DNP sample under the same conditions under which the DNP experiment is performed This data is critical for choosing the best polarizing agents and sample preparations for maximizing DNP sensitivity In recent years DNP has proven to be a robust method for increasing signal intensities in NMR experiments in laboratories around the world and substantial progress has been made in adapting DNP for solid state NMR spectroscopy To understand and optimize the DNP process it is crucial to fully understand the EPR spectrum and relaxation parameters of the polarizing agent However less than a dozen academic groups have succeeded in building the high field spectrometer required to measure them leaving researchers with little more than an educated guess regarding their sampleandapos s EPR properties We propose to market an affordable compact EPR spectrometer that can easily be adapted to cover the complete frequency range currently used in DNP spectroscopy The system can either be added to already existing gyrotron based DNP system or allows the upgrade of an existing NMR spectrometer to do DNP spectroscopy The spectrometer will be compact and turnkey so that the system can also be used by non experts During this project we will move the GHz prototype EPR spectrometer to a st generation product and design and fabricate components that are required to retrofit existing NMR spectrometers and demonstrate their performance on a MHz DNP NMR spectrometer at a collaboratorandapos s site With this technology researchers can accurately determine EPR characteristics so they can develop new optimized polarizing agents maximize DNP sensitivity and accelerate their research This will be of large interest to many projects funded by the U S National Institutes of Health Project Summary Abstract Dynamic Nuclear Polarization has the capability to drastically enhance the inherently small signal intensities observed in solid state magic angle spinning NMR experiments The method is of great interest to the structural biology community which uses NMR spectroscopy for structure determination of small and large bio macro molecules areas that are vital for several research projects funded by the U S NIH