I joined the Millimetre Waves & High Field EPR Group at St Andrews in 2013, to commence study towards a PhD in Electron Spin Resonance. I gained my MPhys from St Andrews in 2012, spending my research project working with Dr. Graham Smith implementing composite pulses in high field EPR experiments. After a year in US as part of the Bobby Jones Scholarship program to Emory University in Atlanta, I have now returned to St Andrews to continue my work with Graham and the Millimetre Wave & High Field EPR Group. While at Emory I worked with Dr. Kurt Warncke's group examining the dynamics of short distance biradicals in cw X-band experiments.
My research is currently focused on novel techniques to improve the sensitivity of measurements in high field EPR experiments through the use of composite pulses and optimal control. High field EPR is becoming particularly useful for exploring the orientational dynamics of spin-labelled proteins, due to lifting of the degeneracy of the g-tensor at higher fields. However, this results in a broadening of the excitation bandwidth, which requires broad excitation and sufficient excitation power to ensure successful manipulation of the spins. This effect is coupled with issues of applied field inhomogeneity and applied field offset, signals from such experiments require long averaging times to compensate for reduced signal to noise as a result of these imperfections. By using a set of non-standard pulses, we can utilise techniques to compensate for these imperfections. This technique has been proven to be very successful in NMR experiments, providing broadband excitation while compensating for substantial applied field inhomogeneities. It is hoped that this technique may be extended to utilise Optimal Control Theory to create pulses/pulse sequences that further enhance the performance of compensation pulses.
As well as exploring pulse methodologies, I am currently engaged in a ground-up approach, testing techniques to improve sensitivity in terms of sample preparation and reducing losses that are inherent in the system.
Claire L. Motion, Janet E. Lovett, Stacey Bell, Scott L. Cassidy, Paul A. S. Cruickshank, David R. Bolton, Robert I. Hunter, Hassane El Mkami, Sabine Van Doorslaer & Graham M. Smith, "DEER Sensitivity between Iron Centers and Nitroxides in Heme-Containing Proteins Improves Dramatically Using Broadband, High-Field EPR", J. Phys. Chem. Lett., 7(8), 1411-1415 (2016) DOI: 10.1021/acs.jpclett.6b00456
Claire Motion, P.A.S. Cruickshank, D. Bolton, R.I. Hunter, H.E. Mkami, G.M. Smith,
41st Southeastern Magnetic Resonance Conference, Raleigh Convention Center, North Carolina, USA, November 15-17th 2012.