“…In recent years, as the biophysical research toolbox expands rapidly, both in terms of technology and instrumentation, it has become very clear that deuteration of proteins and other biomolecular samples will greatly aid in high-quality outcomes for other biophysical applications, particularly small-angle neutron scattering (SANS) ( 14 , 15 , 16 , 17 ), pulsed double echo electron resonance (DEER) techniques ( 18 , 19 , 20 ), and neutron reflectometry ( 21 , 22 ). The general requirement is to effectively remove, or make nonresponsive, a component of the measurement as a result of perdeuteration, either through contrast matching as in SANS ( 23 ) or elongation of relaxation times via removal of dipolar coupling as in DEER and NMR ( 3 , 7 , 24 , 25 ). The SANS and NMR methods are further enhanced in the context of segmental labeling ( 26 , 27 , 28 , 29 ), wherein portions of a macromolecule may be prepared with deuteration for SANS (and/or isotopic labeling for NMR) and the other portions are protonated.…”