Deuterium NMR Studies of Surface Electrostatics
نویسنده
چکیده
The utility of H NMR spectroscopy of headgroup deuterated amphiphiles as a tool for measuring charge density at the surface of lipid bilayer membranes and polymer colloids is described. Attention is given to current ideas regarding the physical origin of the spectral changes observed in the presence of surface charges, and to several novel applications of the technique including determination of the pKa of surface bound ionizable groups, measurement of equilibrium ligand-surface binding isotherms, observation of lateral phase separations of charged membrane species, resolution of charge differences at the inner versus outer monolayer surfaces of a lipid bilayer, and estimation of the electrostatic charge at the surface of a colloidal particle. 223
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