High efficiency motility of bacteria-driven liposome with raft domain binding method.

From the viewpoint of energy efficiency and size reduction, many people have proposed the use of microbes as actuators. Some bacteria can swim in an aqueous environment. Therefore, flagellated chemotactic bacteria have been utilized as actuators for the propulsion of micro-objects by randomly attaching several bacteria to their surface. A liposome is a well-known component used for drug delivery that can contain biologically active compounds. In the present study, we used an antibody and biotin-streptavidin binding technique to combine bacteria and liposomes and create bacteria-driven liposomes. Furthermore, a novel raft domain binding technique was developed and used to limit the attachment of bacteria to small areas of the liposome surface. The effect of the number and configuration of the attached bacteria on propulsion speed was then studied experimentally. The motility of the raft domain liposome with bacteria was higher than that of the normal liposome with bacteria. This method could be used to create bacteria-driven liposomes with highly efficient motility and could lead to the development of microrobots as drug delivery systems.