Petelska AD, Naumowicz M, Figaszewski ZA. 2002. Interfacial tension of the bilayer lipid membrane. Cell Moll Biol Lett 7:212.

A regularity has been found: a larger hydrophilic head gives rise to a lower interfacial tension. A relationship was found between the size of the hydrophilic head of lipid and the isoelectric point pH value. With larger hydrophilic heads, the isoelectric point appears at lower pH.