Formation and transport of nanotube-integrated vesicles in a lipid bilayer network

We present a micromanipulation method to create, load, and transport vesicles (with diameters of similar to500 nm to 5 mum) between two surface-adhered giant vesicles conjugated by a suspended nanotube. The walls of the lipid bilayer (two-dimensional liquid crystal) of the nanotube-integrated mobile vesicles are continuous with the nanotube walls and, thus, are 2-fold open-ended. Nanotube-integrated vesicles are created by the injection of excess membrane material into a surface-adhered vesicle. The transport of vesicles along the nanotubes is controlled using a difference in membrane tension that is caused by shape deformation of the surface-adhered vesicles using micromanipulator-controlled carbon fibers. When reaching a surface-adhered vesicle, a mobile vesicle can empty its contents into it on demand. This way, reactants or other chemical or physical cargo can be delivered into a neighboring vesicle to, for example, titrate a chemical substance or provide reactants to initiate a chemical reaction. This system is capable of controlled transport and handling of minute volumes (10(-12)-10(-18) L), via manipulation of the energy state of the device material itself, and creates new possibilities for performing chemistry in aqueous phases at the nanoscale and microscale, as well as in the construction of nanofluidic devices.