The 1966 science-fiction movie Fantastic Voyage famously imagined using a tiny ship to combat disease inside the body. With the advent of nanotechnology, researchers are inching closer to creating something almost as fantastic. A microscopic device that could swim through the bloodstream and directly target the site of disease, such as a tumor, could offer radical new treatments. To get to a tumor, however, such a device would have to be small and agile enough to navigate through a labyrinth of tiny blood vessels, some far thinner than a human hair.
At the IEEE biorobotic conference 2008, researchers of the École Polytechnique de Montréal, in Canada, led by professor of computer engineering Sylvain Martel, showed to have coupled live, swimming bacteria to microscopic beads to develop a self-propelling device, dubbed a nanobot. While other scientists have previously attached bacteria to microscopic particles to take advantage of their natural propelling motion, Martel’s team is the first to show that such hybrids can be steered through the body using magnetic resonance imaging (MRI). To do this, Martel used bacteria that naturally contain magnetic particles.