Post-print (lokagerð höfundar)Dynamic nuclear polarization (DNP) is an efficient method to overcome the inherent low sensitivity of magic-angle spinning (MAS) solid-state NMR. We report a new polarizing agent (bcTol), designed for biological applications, that yielded an enhancement value of 244 in a microcrystalline SH3 domain sample at 110 K.This work was financially supported by the Icelandic Research Fund (141062051), the Deutsche Forschungsgemeinschaft (SFB 1078, 740 and 765) and by a doctoral fellowship to A. P. J. from the University of Icelandic Research Fund. We thank A. Diehl, K. Rehbein, N. Erdmann and D. Michl for the preparation of microcrystalline SH3 and channelrhodopsin samples, Dr S. Jonsdottir for assistance in collecting analytical data for structural characterization of the radicals, as well as P. Hegemann and K. Stehfest for helpful discussions concerning expression and purification of channelrhodopsin.Peer reviewe
