title: Scanning calorimetric evidence for a third phase transition in phosphatidylcholine bilayers.
abstract: A third phase transition, centered at about 18 degrees C, was observed by differential scanning calorimetry in a multilamellar suspension of dipalmitoyl phosphatidylcholine that had been held at 0 degrees C for several days. This transition is less cooperative than the other two transitions which are well known for this system, and it is accompanied by an enthalpy increase about three times as large as that of the so-called pretransition at 35 degrees C and about half that of the main gel to liquid crystal transition at 41 degrees C. The reversal of this transition on cooling is extremely slow.
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D002152:Calorimetry, Differential Scanning; D008081:Liposomes; D008567:Membranes, Artificial; D011663:Pulmonary Surfactants; D013696:Temperature; D013997:Time Factors
chemical_list: D008081:Liposomes; D008567:Membranes, Artificial; D011663:Pulmonary Surfactants