Distribution of pore sizes in black lipid membranes treated with nystatin.

Resistance changes were measured on artificial membranes made of oxidized cholesterol and treated with nystatin. The experimental data were smoothed and then fitted to a mixture of Gaussian functions using the maximum likelihood method; the best fit was to a mixture of four gaussians centered approximately at 4, 6, 9 and 12 molecules per pore, leading to the conclusion that these are the most likely pore sizes.