TWO-FACED TUMBLE: Silica microcapsules are coated on one half with magnetic iron particles and the other half with an enzyme that breaks down urea in human fluids to cause chemo-osmotic propulsion. The capsules can deliver cargo such as drugs to target sites.REDRAWN FROM SANCHEZ ET AL., ACS NANO, DOI:10.1021/acsnano.5b08067
In the 1966 film Fantastic Voyage, Czech scientist and defector Jan Benes discovers a way to miniaturize matter, enabling his colleagues to navigate a pint-size submarine through his blood vessels and into his own brain to destroy a lethal blood clot. Today, this sci-fi gem is edging closer to reality. With the help of microfabrication, researchers are beginning to learn how to deploy tiny, cellular-scale machines into biological systems.
Micromotors of all shapes and sizes are being developed to sense environmental toxins in air or water, deliver drugs to target tissues, and perform surgical procedures at the single-cell level. What complicates their use in living organisms or cell-culture systems, however, is that their tiny size leaves them struggling against fluid forces. While a large ship ...
