NUCLEAR MAGNETIC-RESONANCE SPIN-SPIN RELAXATION-TIME IN HYDRATED PROTEIN POWDERS - 2 SITE DYNAMIC EXCHANGE MODEL

The NMR spin-spin relaxation time of water in hydrated protein powder is analyzed by using a two-site dynamic exchange model. An expression is derived for the population fraction of stronger bound water molecules by using Guggenheim adsorption isotherm. The model is applied to the published experimental results from the NMR of lysozyme. A linear relationship is found between the spin-spin relaxation time of water fixed to primary binding sites and water content. © 1979 American Chemical Society.