FIGURE 6.
Calculated cholesterol chemical activities as a function of cholesterol concentration. Chemical activities (which are related to chemical potentials) are calculated using Equation 2, as described under “Experimental Procedures,” for binary membrane mixtures of cholesterol and phospholipid assuming no interactions (black curve), a complex containing one cholesterol and two phospholipid molecules (Keq = 200, blue curve) and a cooperative complex containing 10 cholesterol and 20 phospholipid molecules (Keq = 20010, red curve).