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Double electron electron resonance (DEER) is an EPR technique which allows for distance measurements on the nanometer scale. Here, EPR-based distance measurements were extended to in-cell applications. From evaluation of nitroxides for experiments in intracellular environment of Xenopus laevis oocytes and through proof-of-principle experiments optimal parameters for performing in-cell DEER were found. On the example of G-quadruplexes formed by oligomers of human telomeric DNA, DEER was shown to be applicable for structural identification of biological objects under their native conditions.

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Mykhailo Azarkh studied chemistry at the Kyiv National Taras Shevchenko University (Kyiv, Ukraine). He continued his graduate studies at the University of Konstanz (Germany) where he had received his Ph.D. degree in 2012.

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