PHOSPHOLIPIDIC MONOLAYERS ON FORMAMIDE

We report the first phase diagram of a Langmuir him at the air-formami de interface. Stable films of phospholipids such as DPPC or DSPC under go phase transitions observed on isotherms or by fluorescence microsco py. They display bidimensional gas, liquid and solid phases, as well a s two mesophases; the latter coexist with liquid on a sharp first-orde r transition plateau. We compare these observations with known results on films on water.