| In this work we employed Atomic Force Microscopy(AFM) to study the phospholipid bilayer. First, we studied the mechanism of supported lipid bilayer formation, when a vesicle solution is put in contact with a hydrophilic substrate. We have found that the bilayer line tension is the driving force that renders the supported lipid bilayer uniform, while the interaction with the substrate slows down the bilayer reorganization. Then, we studied the mechanism of domain formation during the first order phase transition of a supported phospholipid bilayer. Our measurements suggest that nucleation is the main mechanism of aggregate growth during the solidification process. Diffusion measurements, AFM height measurements corroborated with previous studies on similar systems indicate that the diffusion is slowed by interdigitation. Slowing of the growth is a way of achieving small nanoscale aggregates. Finally, we imaged the aggregation and growth of Aβ amyloid peptide incubated both alone and in vesicle solution. We believe that our real-time work on nanoscale phase separation in lipid bilayers combined with the experience of imaging the amyloid in situ sets the basis for possible real-time imaging of Aβ peptides interacting preferentially with certain lipid domains within an artificial membrane.*; *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirement: Adobe Acrobat. |
