Interactions of amphiphilic and polyphilic block copolymers based on hydrophilic poly(glycero monomethacrylate) blocks, hydrophobic poly(propylene oxide) and perfluorinated alkyl segments were studied with DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) derivatives, including amonofluorinated lipid F-DPPC(1-palmitoyl-2-(16-fluoropalmitoyl)-sn-glycero-3-phosphocholine), an ether analogue DHPC(1,2-di-O-hexadecyl-sn-glycero-3-phosphocholine) and acationic lipid EDPPC (1,2-dipalmitoyl-sn-glycero-3-ethylphosphocholine).The monolayer behavior of modified lipids was different from that of DPPC. The Liquid expanded (LE) to liquid condensed (LC) phase transition took place at higher surface pressures compared to DPPC and LC-domains visualized by epifluorescence microscopy had fractal growth, indicating the dominance of electrostatic dipolar forces in the monolayers. With the exception of cholesterol linked polymer, the aggregation of lipids was hindered in the mixtures containing low proportions of all polymers and facilitated when polymer content exceeded 5%. The cryo-electron microscopy and differential scanning calorimetric investigations revealed the temperature driven fusion of interdigitated lipid vesicles. All polymers induced defects in the interdigitated gel phase of lipids, resulting in the broadening or splitting of melting and crystallization transitions. |