(351a) Magnetic Enhancement of Phototaxing Catalytic Motors

Asymmetric colloidal doublets have been shown to undergo phototaxis. Micron-size colloidal heterodoublets of silver-polystyrene latex microspheres and silver-silica microspheres were fabricated using the ?salting out-quenching? technique. The asymmetric colloidal doublets behave as catalytic motors and show self-propulsion and phototaxis under ultraviolet light in the presence of hydrogen peroxide by the mechanism of diffusiophoresis. Magnetic enhancement of phototaxis has been observed with magnetic doublets. Magnetic heterodoublets of silver-magnetic polystyrene latex microspheres were fabricated using the ?pH controlled assembly? technique. Catalytic magnetic doublets align themselves in response to an external magnetic field and form exclusion regions around them under ultraviolet light in the presence of hydrogen peroxide. This talk will demonstrate a simple, quick and inexpensive approach for the fabrication of synthetic motors capable of performing directed motion and forming exclusion zones and patterns. The fabrication of small scale synthetic motors is an important step in developing practical nanomachines, which can be used for several applications including roving sensors, drug delivery vectors, and self-assembly of superstructures.