Saxena Group is focused on developing Fourier Transform electron spin resonance and its application to otherwise inaccessible problems in biophysics. The coupling of electron spin angular momentum to its environment—as revealed by the ESR spectrum—provides rich information about the electronic, structural and dynamical properties of the molecule. Saxena group creates the methods that measure the precise distance between two units in a protein, in order to determine their folding patterns and conformational dynamics. These ESR Spectroscopic Rulers— based on multiple quantum coherences and double resonance experiments—are unique in that they resolve distances in the 1-16 nm length scale even on bulk amorphous materials. Much of this work is based on the use of first-principles theory to develop new experimental protocols and to analyze experimental results.
His group continues to develop applications of these spectroscopic rulers that range from capturing the essence of structural changes - such as misfolding - in proteins, to measuring the atomic-level details of ion-permeation in a ligand gated ion-channel. The main projects of his group include:
Pulsed ESR methods to measure distance constraints in systems containing paramagnetic metals
Measurement of structural and dynamical determinants of the protein-DNA interactions and functional dynamics in pentameric ligand gated ion-channels.
Application of the spectroscopic ruler to measure and predict global structures of nanostructured materials.
Role of metals in aggregation of Amyloid-β peptide.
"Nonlinear-least-squares analysis of slow-motion EPR spectra in one and two dimensions using a modified Levenberg–Marquardt algorithm." David E Budil, Sanghyuk Lee, Sunil Saxena, Jack H Freed. Journal of Magnetic Resonance, Series A.
"Amplification of xenon NMR and MRI by remote detection." Adam J Moulé, Megan M Spence, Song-I Han, Juliette A Seeley, Kimberly L Pierce, Sunil Saxena, Alexander Pines. Proceedings of the National Academy of Sciences.
"Double quantum two-dimensional Fourier transform electron spin resonance: Distance measurements." Sunil Saxena, Jack H Freed. Chemical physics letters.
"Theory of double quantum two-dimensional electron spin resonance with application to distance measurements." Sunil Saxena, Jack H Freed. The Journal of chemical physics.
"Direct Evidence That All Three Histidine Residues Coordinate to Cu(II) in Amyloid-β1−16." Byong-kyu Shin, Sunil Saxena. Biochemistry.
"19F Paramagnetic Relaxation-Based NMR for Quaternary Structural Restraints of Ion Channels." Vasyl Bondarenko, Marta M Wells, Qiang Chen, Kevin C Singewald, Sunil Saxena, Yan Xu, Pei Tang. ACS chemical biology.
"Effects of MnO2 of different structures on activation of peroxymonosulfate for bisphenol A degradation under acidic conditions." Jianzhi Huang, Yifan Dai, Kevin Singewald, Chung-Chiun Liu, Sunil Saxena, Huichun Zhang. Chemical Engineering Journal.
"Designing Open Metal Sites in Metal–Organic Frameworks for Paraffin/Olefin Separations." Mona H Mohamed, Yahui Yang, Lin Li, Sen Zhang, Jonathan P Ruffley, Austin Gamble Jarvi, Sunil Saxena, Götz Veser, J Karl Johnson, Nathaniel L Rosi. Journal of the American Chemical Society.
"An Undergraduate Experiment To Explore Cu (II) Coordination Environment in Multihistidine Compounds through Electron Spin Resonance Spectroscopy." Eugene P Wagner, Kai C Gronborg, Shreya Ghosh, Sunil Saxena. Journal of Chemical Education.
"Innentitelbild: EPR Spectroscopy Detects Various Active State Conformations of the Transcriptional Regulator CueR (Angew. Chem. 10/2019)." Hila Sameach, Shreya Ghosh, Lada Gevorkyan‐Airapetov, Sunil Saxena, Sharon Ruthstein. Angewandte Chemie.