A Resonator for Pulsed ODNP Spectroscopy to Study Surface Hydration Dynamics

Project SummaryAbstractThe proposed research focuses on the development of a turn key resonator for liquid state Overhauser Dynamic Nuclear PolarizationODNPspectroscopy to study the site specific translational dynamics of water molecules located at the interface of bio macromolecules such as membrane proteinsIt will allow researchers to readily perform ODNP experiments in a state of the art commercially available X band cw pulsed electron paramagnetic resonanceEPRspectrometerIn recent yearsDNP has proven to be a robust method to increase signal intensities in NMR experiments in laboratories around the world and substantial progress has been made in adapting DNP for solidand solutionstate NMR spectroscopyThis progress has sparked a new interest in ODNP spectroscopyAlthough the method is known since thes it has just recently been applied successfully to study the site specific translational dynamics of water located at the interface of large bio macromolecules such as membrane proteinsODNP can map out the local and site specific hydration dynamics landscape of membrane proteins and lipid membranes and can provide critical information about the protein structure and dynamicsOne of the major challenges in ODNP spectroscopy is microwave induced sample heatingIn this SBIR Phase I application we propose to develop a turn keyODNP resonator compatible with state of the art continuous wave or pulsed X Band EPR spectrometerwhich can be found in many academic spectroscopy facilitiesThe resonator will have a much higher microwave conversion factor compared to conventional rectangular or circular EPR cavitiesIn additionthe low Q resonance structure will allow pulsed ODNP experiments to further minimize microwave induced heating by reducing the average power required to saturate the EPR transitionsThe successful development of this technology will provide researchers access to instrumentation allowing them to incorporate ODNP spectroscopy in their research routine without the hassle of troubleshooting home built equipmentThis will greatly proliferate the method and is of large interest to many projects funded by the U SNational Institutes of Health Project SummaryAbstract Overhauser Dynamic Nuclear PolarizationODNPspectroscopy can be used to study the hydration dynamics of bio macromolecules such as membrane proteinsbut currently there is no cost effectiveturn key ODNP resonator availableThis severely limits the usage of the techniqueThe proposed ODNP resonator is an addon to state of the art cw pulsed EPR spectrometer that can be found in many academic spectroscopy facilitiesThis will make the method available to a much broader audience and proliferate research that is at the heart of the National Institutes of Health