The surface pressure (Π) and surface area/molecule (A) isotherms of a mixture of DMPC (DL-α-phosphatidylcholine, Dimyristoyl) and PEG-DMPE (1,2-Diacyl-sn-Glycero-3-Phosphoethanolamine-N-[Poly(ethylene glycol)5000]) system were measured at various compositions by the Langmuir surface balance technique at an air/water interface. In the range where the surface pressure is less than about 8 dynes/cm, a PEG polymer chain of PEG-DMPE molecules remains on the surface and the isotherm can be explained by the 2-D power law behavior of chains in a good solvent. In the range above 8 dynes/cm, a part of the PEG polymer segment is dissolved into the water phase, and the surface pressure can be explained as the sum of the 2-D component and 3-D component. Furthermore, the mixing energy is negative, which indicates an attractive interaction between DMPC and PEG-DMPE.
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Research Article| June 22 2000
Lipid and lipid-polymer mixtures at an interface
Joon Heon Kim;
AIP Conf. Proc. 519, 446–457 (2000)
Joon Heon Kim, Mahn Won Kim; Lipid and lipid-polymer mixtures at an interface. AIP Conf. Proc. 22 June 2000; 519 (1): 446–457. https://doi.org/10.1063/1.1291601
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