Electron Paramagnetic Resonance (EPR) spectroscopy is a powerful technique for studying paramagnetic species, providing unique information on molecular structure, dynamics and interactions, often inaccessible by other spectroscopic methods. Originally developed for the characterization of radicals and transition metal complexes, EPR has evolved into a versatile tool with applications spanning chemistry, materials science and biology.

In this seminar, I will introduce the basic principles of EPR spectroscopy and discuss how modern EPR methodologies can address fundamental chemical and biological questions. Particular emphasis will be placed on the use of site-directed spin labeling to investigate the conformational dynamics, structural organization and intermolecular interactions of proteins in solution and, more recently, directly inside living cells.

In this talk I aim to demonstrate how EPR complements established structural biology techniques and why it is becoming an increasingly valuable approach for studying complex molecular systems, bridging the gap between chemistry, biophysics and molecular biology.