The researchers from the University of California, Santa Barbara called the nanotubes "smart" because they can open or close at the ends, depending on how the researchers manipulate the electric charge on the two components. So in principle, a nanotube could encapsulate a drug or a gene, and then open on command to deliver the cargo where it would have the best effect.
The tube's components play roles similar to skin and bone. The "skin" is a soap-bubble-like arrangement of molecules known as a lipid bilayer, akin to the bilayer that forms the cell's protective outer membrane. The "bone" is a hollow, cylindrical structure known as a microtubule, which is ubiquitous in the cell's internal cytoskeleton, the system of nanoscale struts and girders it uses for internal transport, structural stability and many other purposes.
The researchers have found that when they combine the two components and control the conditions properly, open or closed bio-nanotubes will assemble themselves spontaneously.
COMPAMED.de; Source: National Science Foundation