Lipid fluidic

For an artificial lipid bilayer of any size scale, it is a general feature that the bilayer acts as a two-dimensional fluid due to the presence of the water cushionlayer between the bilayer and the substrate. Due to this fluidic nature, molecules incorporated in the lipid bilayer show two-dimensional free diffusion. By applying any bias for controlling the diffusion dynamics, we can manipulate only the desired molecule within the artificial lipid bilayer, which leads to the development of a molecular separation system. 

Controlling Molecular Diffusion in the Fluidic Lipid Bilayer... 

The second example of a biological supermolecule is a cell membrane. As described in Chap. 4, a cell membrane consists mainly of a fluidic lipid bilayer containing proteins (Fig. 6.2). The Hpids are self-assembled into the bilayer structure and the proteins float within the Hpid bilayer. The whole structure is formed through self-assembly processes. 

Ultrasonic standing wave (USW) manipulatiOTi is a simple and useful method for handling, separating, and concentrating large groups of cells. A USW creates a pressure node that will attract particles or cells. As with DEP, a cell can experience either an attractive or repulsive acoustic force depending on its material parameters. This can be used either to trap objects locally over an ultrasonic transducer, concentrate them within a fluidic channel, or separate different types of objects from each other. Successful separation of human erythrocytes from human lipid vesicles has been reported (Fig. 5). 

The functions of liposomes, such as interaction, incorporation, recognition, and stabilization, are attributed to the microfluidity of a membrane and its ttansitional state [2], Lipids dispersed in water can form a variety of structures, for example, the liposome-type structure at low lipid/water ratios. As temperature increases, the lipid phase shifts from a crystalline to a condensed gel-like state and then to a fluidic, expanded state, and such a transition state at the corresponding temperature can be determined by various methods [2,16]. 

---