Pure DPPC shows a typical behavior, in line with the data reported in the literature (Table ). At 25°C and an area per molecule higher than 100 Å 2 , DPPC is in a gas phase (P= 0 mN/m). By continuing the compression, the surface pressure increases to reach a plateau at P= 10 mN/m which corresponds to the liquid expanded to liquid condensed (LE-LC) phase transition.