Studies on Surface Denaturation of Egg Albumin*

Bull and Neurath (1) have reported a study of the kinetics of surface denaturation of egg albumin. The protein solutions were shaken in bottles for varying lengths of time, and the amount of denaturation determined. It was not possible, however, in their studies to establish the effect of the extent and rate of formation of surface. The present paper reports a study of surface denaturation occurring on a drum of known dimensions dipping into a protein solution and rotated at known speeds. This allows one to establish the effect of the rate of creation of new surface and to calculate the amount of denatured protein on unit area of the rotating drum as a function of speed of rotation and of concentration. The principal purpose of this study is thus to extend the work of Bull and Neurath on the kinetics of surface denaturation. It has been found, however, that the amount of denaturation is a smooth function of the speed of rotation of the drum and approaches certain limiting values as the speed of rotation is diminished. The amount of denatured protein in the surface film can thus be extrapolated to zero speed of rotation and an approximation of the conditions and structure of the surface film on a quiescent protein solution is obtained.